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critter
06-04-2011, 02:34 PM
The car: 1974 Trans Am:

https://static1.pt-content.com/images/pt/2011/02/1stance-1.jpg

This all started several weeks back. I had been to a car show. My sister had invited me over for dinner that night so I planned to drive from the show to her home. I made it most of the way before the car quit running. I was cruising along at about 50mph when it was like someone flipped a switch.

My brother in law, Bryan Blocker of Blocker's Performance and Restoration, came over with some tools and we began to diagnose. We discovered we had no fire to the plugs and when I yanked the distributor we found that three teeth were gone from the BOP composite gear I run with my hydraulic roller cam.

https://static1.pt-content.com/images/pt/2011/06/distributorgear-1.jpg

We towed it back to his shop. The building was full with customer's cars and I told him to put it on the back lot, I'd throw my cover over it, no problem. We went ahead and pulled the intake and valley pan to see if anything obvious poked its head up but it didn't. We simply laid the valley pan and intake back on top of the motor, threw the cover on and walked away. I was headed out on vacation the next week so I figured it would set until I got home.

Unfortunately I got home and then the tornado hit Vilonia, Arkansas. That's where Bryan has his shop. He called me that night to say the cover had blown off but the car hadn't suffered any damage he could see. Considering I had family in the path of a killer tornado (4 died that night) I didn't give a darn about the car. So we spent the next 2 weeks cleaning up storm damage.

I decided to put a new gear on the cam, hoping it was a simple gear failure since nothing else was apparent, and see if I could start it long enough to put it on a trailer. I started by draining the oil from the block through a cloth to see if I caught anything. 2 gallons of rain water later we got to the oil. Nothing there. I then poured a fresh 5 quarts of oil through the block to see if I could chase the water out. Then I topped it off, put in new gaskets, buttoned it up and gave it a shot. It fired right up and ran about 4 seconds and died. I pulled the distributor. This time it broke the gear in half.

So the roll back was called and the dropped it at my house. The motor had to come out.


https://static1.pt-content.com/images/pt/2011/06/out-1.jpg

I did that today.

I started tearing it down. One think I was curious to see was how the Keen-sert I put in the block that time had held up. It did well. It's in the lower, center part of the picture. for those who don't know, I tried to re-torque a head bolt prior to NFME back in 2008. The threads stripped out of the block. I made a jig using an old head, drilled it and installed the Keen-sert while the block was in the car. It's still going strong! The other thing you'll see is carbon build up on the pistons. The driver's side head needs new valve guides.

https://static1.pt-content.com/images/pt/2011/06/keensert-1.jpg

Removing the lifters I spotted this. The #1 lifter had a spot that was galled on one side.

https://static1.pt-content.com/images/pt/2011/06/gall-1.jpg

And it matched a spot on the cam lobe. It's hard to see in this picture but it's there.

https://static1.pt-content.com/images/pt/2011/06/marks-1.jpg

So all of this to say this thread will be about the tear down, diagnosis on why it did this and the build of a new engine. That engine will probably be a 461ci based on a 400 block and using a stroker kit. Watch for updates.

Jims78elky
06-04-2011, 05:47 PM
Bummer about the distributor..ouch! :sick:

I Like the updates..Keep it up Critt!

andrewb70
06-04-2011, 06:25 PM
Time for a LS3...

Andrew

critter
06-05-2011, 03:59 AM
LOL. It was considered. But I love my Pontiacs with Pontiac power so after the tear down it will most likely be a build thread for a Pontiac 400, stroked to make a 461ci motor.

LeighP
06-05-2011, 05:59 AM
Go Chris! :)

My427stang
06-05-2011, 06:55 AM
I have started running steel gears on billet cores. You need to talk to the cam manufacturer on what the materials are on their core. Dissimilar materials are bad, but usually steel to steel is an option.

You of course can't run cast iron with billet, but steel to steel is fine, and you dont have to deal with fragile composite or bronze that eventually wears out.

The sacrificial gears are of course good for a racer, but anything that puts a lot of miles on, I prefer steel to steel

critter
06-05-2011, 08:54 AM
Crane used to do pressed on steel gears but they went out of business. Of course all their grinds were old technology anyway. If the cause is indeed cam wear I will look into it.

Only a complete tear down, which I'll do over the next few days, will tell but I bet that I'm going to find a worn cam thrust plate.

critter
06-06-2011, 06:40 PM
Tonight's continuation of the teardown gave me the apparent cause of the gear breakage and the results of what happens when you don't pay attention to detail.

First thing I noticed after getting the lifters out was the excessive end play on the cam. It measured at .064. WAAAYYY too much. That should be more like .004 - .007.
https://static1.pt-content.com/images/pt/2011/06/endplay-1.jpg

Removing the thrust plate revealed a lot of wear. The picture doesn't do justice to the groove worn into that retaining plate.
https://static1.pt-content.com/images/pt/2011/06/thrustplate-1.jpg

But the real kicker was when I flipped the engine over. Yes, that's the oil pump pickup laying there and yes that's the half a cam gear laying up there, just where it was when I pulled the pan.
https://static1.pt-content.com/images/pt/2011/06/pickup-1.jpg

The crazy part is that I never had an oil pressure problem. It also shows that, though I thought I remembered tack welding that pickup, I obviously didn't . DETAILS! DETAILS! DETAILS! No one to blame but myself since I assemble my motors myself. I did it. I didn't pull rods or the crank yet but all the cam bearings look great. So my gut feeling is that the cam thrust issue was breaking gears and I was still getting oil pressure because the pickup didn't fall all the way out until I flipped the engine over on the engine stand. I'll know more regarding the pickup issue tomorrow when I pull that stuff apart.

Another downer was the cam. When it came out I noticed a lot of "spots" on the cam. They correspond with where the lifters contacted the lobes on the cam and water got under them. Basically, rust. I think the cam is toast and at least one lifter set.


https://static1.pt-content.com/images/pt/2011/06/camspots-1.jpg

MrQuick
06-06-2011, 10:40 PM
surprised that it wasn't tacked on. Was the pump seized?

critter
06-07-2011, 02:40 AM
Nat as surprised as me. I'm the guy who should have tacked it. How the heck I missed doing that I don't know. Still, I don't think oil delivery was my problem. None of the cam bearings looked bad. I'll tear down the rods and mains tonight and those bearings will tell me if there really was any oil delivery issue.

The pump was not seized. It turns easily by hand.

critter
06-07-2011, 06:20 PM
The root cause was discovered tonight. As much as I wanted to blame it on cam walk, that wasn't it. When I disassembled the oil pump tonight I found this:
https://static1.pt-content.com/images/pt/2011/06/pump-1.jpg

Laying on the pump base plate is a small piece of metal. As you can see from the teeth on the pump gears that sucker went through there more than once. I found it up next to the check ball in the pump. It looks like casting flash on one side and is smooth on the other. I have to figure the pickup fell off and sucked that into the pump. Here's a closer look.
https://static1.pt-content.com/images/pt/2011/06/metal-1.jpg


I tore down the rest of the block. Here are the rod bearings. A little copper showing on the tops in a few places but for the most part OK.
https://static1.pt-content.com/images/pt/2011/06/rods-1.jpg

And the main bearings. Looks like #2 saw some metal at some point. Lots of copper showing there.
https://static1.pt-content.com/images/pt/2011/06/mains-1.jpg

Anybody need a set of SD rods with .030 over TRW pistons?
https://static1.pt-content.com/images/pt/2011/06/sdrods-1.jpg

So that's about it. This block is pretty good except for the fact that the ear for the starter mounting is broken off.That make's it scrap metal. So it's time to move on. From here I'll be building a 400 block with a stroker kit. I'll post as I go.

MrQuick
06-07-2011, 07:16 PM
I have actually seen this before....the pump will pass metal, increases friction then causes the oil pump housing to over heat and the pickup tube hole expands an the tube falls out.

Finding the weak spot can get expensive.

mc84_zz4
06-07-2011, 08:44 PM
Bummer about the sick engine, but nice dissection of the cause/effects... :1st:

critter
06-19-2011, 09:49 AM
My decision to build a 461 was based on a lot of factors. The primary one being that I'm on a budget and need to re-use my Super Duty #16 heads. So that means I need cubic inches to keep compression up. Another is that the 461 kits are some of the least expensive out there for my horsepower goal, roughly 500.

To that end I had intended to buy a kit from one of the known engine builders. However, a deal popped up on Performance Years forums. A young man had a complete setup, assembeled in a short block. He decided not to go that route after the machine shop misunderstood and put a race fill of hard block in the water jackets rather than the street fill he wanted. So he left the kit in the block while he pondered his situation. Then he had an LQ4 motor fall in his lap. Since he was building a pro-touring car he decided to go with the new technology.

So I purchased all the parts he had in the short block. That included the SRP pistons, 4.155 bore, full floaters, file fit rings, Eagle 6.8 inch rods, a Tomahawk cast crank, 3 inch mains, all bearings, a set of ARP 2 bolt main studs, an SFI rated flex plate from PRW, with bolts, and a Performance Products balancer. He said that they had balanced the assembly but I find no machining marks on the pistons or crank so I'll have to disassemble the stuff and check it. I don't trust them to be good out of the box.

I won't be using that balancer. I have an SFI rated Pioneer unit so it will be for sale. Other than that, I've checked all the parts out and they'll go into this next build. Kudos to Scott for having taken time to mark all the parts and how they were assembled and taking great care when he disassembled it to be sure he didn't damage anything. He was a nice guy and a real car guy. He even met me half way from his home in Oklahoma City to deliver the parts.

Here's a photo of this weekend's take:

https://static1.pt-content.com/images/pt/2011/06/assembly-1.jpg

ponchopower69
06-19-2011, 02:20 PM
Man what a bummer that would be! Im glad to see it getting fixed up even better! Good luck and remember to tack weld the pick-up to the oil pump too lol.

critter
06-19-2011, 02:24 PM
I would but I'm going back with a Canton road race pan so that pickup bolts to the pan. NO CHANCE it comes loose! :)

ponchopower69
06-19-2011, 02:25 PM
Sweet choice!! That will fix it for sure lol!

manicmechanic
06-21-2011, 03:57 AM
Watch out for that canton pick-up, trouble reported over at transam country...

LeighP
06-21-2011, 10:33 AM
Yeah, thats me....I think the pickup I have was a one off manufacturing defect...since I've had it in a box with the RR pan for at least two years...and no one else has reported any trouble.
The pickup tube is welded into the pickup at the wrong angle...won't fit onto the pump. I called Canton and sent pics...they're looking into it.
I couldn't afford to wait on them, I ordered another from Summit, should be here in a couple of days.
I do like the bolt on pickup design.

critter
06-21-2011, 10:40 AM
Thanks for the heads up. Leigh, pictures over on TAC?

The Stickman
06-21-2011, 01:47 PM
Is it fixed yet? LOL.. Keep doing what your doing. Gonna be a great engine when its done.

Torquedork
06-21-2011, 04:37 PM
I may be full of beans and am not a Pontiac engine expert but I'd still pay attention to the cam end play or cam walk especially on a roller cam where it may be more crucial.

As others have said, matched gears in material can also make a difference and both may keep ugly pieces of material out of your oil pump.

rohrt
06-21-2011, 05:57 PM
did you go back to a stock cam retainer or did you go with one of the aftermarket ones from nitemare performance or Simm's Engineering retainer plate?

critter
06-21-2011, 06:08 PM
Simms is on a cross country bicycle trip. I don't blame him. I'd do the same if I could take a year off. Nightmare is on the list of possibles. I'd rather have the Simm's since it incorporates a true roller bearing but I can see where any additional oil flow to the cam end would be beneficial.

A friend of mine who does a lot of technical writing for HPP put out feelers to 3 of the top engine builders in the Pontiac trade. They all came back with the same answer. Excessive end play is not the fault of the stock Pontiac thrust plate. They say look for another cause.

critter
06-24-2011, 06:16 PM
I found a little time to be in the garage tonight. I mocked up the crank and main bearings to check the clearances. They checked out fine. I was a little worried about the aftermarket crank being accurate but it was. Next up is mocking up the 4 corner pistons/rods to see how far down in the hole we are and see if we need to deck it. Then I'll be heading up to see Marty one night. With luck I'll have to do is a final hone on this block to get it from .030 over to .035 over for these pistons.

rohrt
06-25-2011, 04:57 AM
Did you check the thrust surface on the crank?

I'm sure you know about the horor stories on wiping out the bearings.

critter
06-25-2011, 05:16 AM
I had and I did. Nice and smooth. It was my understanding that the thrust surface issue was limited to a few early production pieces but it never hurts to check.

RicerwannaB
06-25-2011, 05:50 AM
Nice build, I will be following this as I want to do a 461 soon for my GTO.

critter
06-26-2011, 08:30 AM
Today I spent some time weighing the pistons and rods that were already assembled. It's not scientific but since the seller claimed this stuff was balanced I wanted a quick gut check. I was amazed to see that these assemblies were almost identical. Six of the eight came in at 1526 grams and two came in at 1527. Close enough.

https://static1.pt-content.com/images/pt/2011/06/weight-1.jpg

Next on the list was to mock up the crank and pistons on four corners to check the deck height. I never got to trial fitting those rods and pistons because I found my first issue. I'd read that the crank counterweight might need some clearance on on side. It does.

https://static1.pt-content.com/images/pt/2011/06/dsclearance-1.jpg

The other side is close as well. Looks like it's time for a little grinder work.

https://static1.pt-content.com/images/pt/2011/06/psclearance-1.jpg

OLDFLM
06-27-2011, 05:50 AM
Sorry to hear about your engine issues... but it is a good excuse for an upgrade!
I was hoping you'd go with a 440 stroker but that 461 kit will do the job nicely!

Subscribed.

critter
06-27-2011, 06:39 AM
I really considered the 440. Perfect rod/stroke ratio but the heads weren't going to work with it. And if I went aftermarket heads I was still going to have to modify those to make good compression for pump gas. I thought long and hard but this is a street car first and a track toy second so I had to build with that in mind.

OLDFLM
06-27-2011, 12:20 PM
Completely understand... that's why I still have my ported #13s that Jim and Rocky helped me with!
There will be another Pontiac project where they'll be perfect I'm sure!

Are you going to engine and/or chassis dyno/tune the 461 when assembled?

critter
06-27-2011, 01:45 PM
Probably. I have access to both types of dyno but planning that part would be putting the cart before the horse. :) :) :)

critter
06-28-2011, 11:07 AM
Did a little grinder work last night.

https://static1.pt-content.com/images/pt/2011/06/ps-1.jpg

https://static1.pt-content.com/images/pt/2011/06/ds-1.jpg

critter
07-01-2011, 05:29 AM
I had one problem with the block I needed to tend to before going to machine the bores for the extra .005 of clearance. Some of the main cap locating dowels were down in the holes quite a bit. It looked like someone tried putting the caps on wrong and torqued them a bit or something. Anyway, I've seen it before. Since I don't have the slide hammer tool for pulling these I use this method. I weld a washer on the top and use a hammer and cold chisel to pry them out.

https://static1.pt-content.com/images/pt/2011/07/welded-1.jpg


https://static1.pt-content.com/images/pt/2011/07/pry-1.jpg

rohrt
07-01-2011, 12:26 PM
Thats a good tip.

critter
07-12-2011, 04:37 PM
There has been a lot going on but not much time to post. Marty slapped on the torque plate and took it the extra .005 I needed. He said the bores looked good and finish he put on those cylinders is just so pretty!

I had some additional stuff to prep before really cleaning the block so I figured I'd get them out of the way now. First up was removing the passenger side galley plug that is hidden inside the block and drilling it .030 for an oil feed to the distributor gear. This is a common modification on Pontiac blocks to provide direct shot oiling to the distributor gear where it meshes with the cam gear. The first step is to remove (if it's not already out) the freeze plug in the block by driving it out with a drift. Next is to use a long Allen wrench to twist out that 3/8 NPT plug that's down under it.

https://static1.pt-content.com/images/pt/2011/07/plugout-1.jpg

Next is to drill a tiny .030 hole through the center. This is harder than it sounds. How small is .030? Here's a photo with my digital caliper, the bit and a plug to give you an idea:

https://static1.pt-content.com/images/pt/2011/07/size-1.jpg

The trick to this is to drill with a larger bit from the back side of the plug. You have to do this by feel and not break through, then finish the hole with the pin vise and the .030 hole.

https://static1.pt-content.com/images/pt/2011/07/backdrill-1.jpg

And here's what it looks like when you break through:

https://static1.pt-content.com/images/pt/2011/07/bitthrough-1.jpg

I also wanted to tap the front oil galley holes to use a screw in 3/8 NPT plug rather than the standard plugs you find in a freeze plug kit. Those are only staked in to retain them. I've never had a failure with the staked in plugs but I figured since I had the opportunity I'd step up to the screw in plugs and be sure:

https://static1.pt-content.com/images/pt/2011/07/galleytap-1.jpg

That was all for tonight. Next on the list is to check the oil feed hole from the pump and open it up if it's needed. Then I'll be ready to clean the block and start working on assembly.

OLDFLM
07-13-2011, 07:23 AM
Are you going to polish/debur/coat the lifter valley? What other tricks are you applying to the block? Inquiring minds want to know! LOL

craigs73
07-13-2011, 08:06 AM
nice work chris cant wait to see a video of it on a dyne keep up the great work

MyFriendScott
07-13-2011, 05:29 PM
I had one problem with the block I needed to tend to before going to machine the bores for the extra .005 of clearance. Some of the main cap locating dowels were down in the holes quite a bit. It looked like someone tried putting the caps on wrong and torqued them a bit or something. Anyway, I've seen it before. Since I don't have the slide hammer tool for pulling these I use this method. I weld a washer on the top and use a hammer and cold chisel to pry them out.

That's worthy of making it into any Hot Rod, Car Craft, etc. mag as one of the best tips/tricks of all time!

critter
07-14-2011, 05:31 AM
Life is getting busy again but I did manage time to work on mounting the Canton pickup to the Butler Pro-Series oil pump I bought. No big deal here. I did countersink the tab on the pickup with a 1/2 inch bit to make the base plate screw fit flush. Other than that it fit as advertised.

https://static1.pt-content.com/images/pt/2011/07/oilpump-1.jpg

With luck I'll be washing the block this weekend and can start putting it together.

Ty, the block I picked up had already been machined for a stock 400 rebuild. Whomever did the machine work knew Pontiac blocks. They had already de-burred the lifter valley. On my last block I polished the walls to speed oil drain back. I decided not to do that this time. I don't think it makes that big a difference. I also elected to not go with street fill of hard block. I did that on my old block and it worked but the oil temps always ran high. Since this is not a race motor (most days) and more of a street cruiser and occasional weekend warrior I'm going to try running without it. I may regret it later but this is how we learn. :)

I did spend time last night inspecting every oil passage that can be visually confirmed. All of that looked good. Some have complained about the feed hole from the pump having flash blocking it but this one was very clean and as cast. Both galley looked true and clean but a good washing will get the previous build's assembly lube out of there for me to confirm it. I also did a visual inspect on every hole and checked the threads. It looks like the previous shop had chased them all because I didn't find a one that I couldn't screw the hardware into as needed. I'll be using studs for the mains and heads so that is important. We want our torque values to be spot on. :)

I did not have the block decked because I need to mock it up first and see how far in the hole we have the pistons. To do that I had to have it honed out to fit the pistons. That's next on the list as far as the block is concerned.

LeighP
07-14-2011, 08:46 AM
Chris,
I understand the stud bottom end...went that way with mine as well...but the studs on the top end - is that more because of your plans for the alloy heads later?

critter
07-14-2011, 09:05 AM
No, more about the fact that my factory head bolts have been torqued so many times I don't trust them and I had a set of head studs setting around so I figured "why not?". I am on a budget so I'll use these studs that I took in on a trade. I suspect these studs won't work with the aluminum heads anyway.

critter
07-16-2011, 05:12 PM
I managed to get the block to the point of washing it this past week. So this morning it was time to get doing the hard part, cleaning this hunk of iron.

First I had to gather all my supplies. I use a stiff bristle brush, Dawn dishwashing liquid, rifle brushes and swabs along with my pressure washer. I always spray it down with WD40 after I'm done and then start in on the blowing it off with compressed air and do a final wipe down with clean rags. Here's how we started out today:

https://static1.pt-content.com/images/pt/2011/07/supplies-1.jpg

And if anyone ever says why do you need to clean the oil galley with a rifle brush and swabs, well, show them this. The cleanings progress from bottom to top. The block looked clean on the outside so don't judge a book by its cover:

https://static1.pt-content.com/images/pt/2011/07/galleyclean-1.jpg

And when it was all done it looked like a shiny new penny:

https://static1.pt-content.com/images/pt/2011/07/clean-1.jpg

I always know when I've done it correctly. At least one of my hands looks like I've been in a fight with a bobcat:

https://static1.pt-content.com/images/pt/2011/07/hand-1.jpg

NOT A TA
07-16-2011, 06:08 PM
Looks great!

LeighP
07-17-2011, 02:26 AM
No, more about the fact that my factory head bolts have been torqued so many times I don't trust them and I had a set of head studs setting around so I figured "why not?". I am on a budget so I'll use these studs that I took in on a trade. I suspect these studs won't work with the aluminum heads anyway.

lol...thats my plan, too....I ended up going studs on the bottom end because I picked up 4 bolt stud kit cheap off Ebay brand new.....you have to stick with the bargains where you can, so you can afford teh good stuff when you need to.

critter
07-17-2011, 11:51 AM
Good progress today. I started off by measuring all the main bearing clearances. They were very consistent with most being in the .0010-.0015 range. According to the factory service manual that's right in the middle of what's considered acceptable so I give point to the quality of the Tomahawk cast crank.

Once I had that I started looking at the Best Gasket rope seal for the rear main. I had installed rope seals before when we could still buy them with asbestos in them but the last couple I've done have been the viton variety. Everyone reports excellent results with this seal so I opened the package. Here's what comes with it:

https://static1.pt-content.com/images/pt/2011/07/mainsealkit-1.jpg

The first thing I noticed was that the instructions were not engine specific and that it included a tiny little roll pin. The generic instructions state that you drill a hole in the block seal area and put that pin in to keep the seal from rotating. That sent me to the internet. Sure enough, that was designed to be used with blocks that might not have the factory anti-rotation holes like we have in our Pontiac blocks and cap:

https://static1.pt-content.com/images/pt/2011/07/antirotation-1.jpg

So on to what I remember. That is the art/science of jamming the material into the groove and rolling it in. I have an old Craftsman 1/2 inch extension that I inherited from my dad that works wonders for this application:

https://static1.pt-content.com/images/pt/2011/07/rollitin-1.jpg

The cool thing about their kit is that they supply a spacer, backing board so you don't cut your finger and the razor knife to make a clean cut. Talk about idiot proof. Heck, even I can get this right! (I'll probably find out I did it wrong for saying that):

https://static1.pt-content.com/images/pt/2011/07/cutting-1.jpg


https://static1.pt-content.com/images/pt/2011/07/mainsealcut-1.jpg

So the seal went in like a dream, I lubed the bearings with assembly lube and started torquing things down, rotating the crank as I went. Initially it seemed a little tight but as the rear main seal settled it things smoothed out. I asked Tammy to deliver a second opinion. She came out and did one full rotation for me and proclaimed it "smooth" so I'm going to say it. The crank is in:

https://static1.pt-content.com/images/pt/2011/07/crankin-1.jpg

John Wright
07-18-2011, 03:47 AM
Now go get those 8 holes filled!...LOL...looks good.

critter
07-18-2011, 05:46 AM
Working on it but the grandkids are coming to town so progress may slow for a bit. :)

The Stickman
07-18-2011, 07:34 AM
Good work. I would have hacked a finger off doing that seal.

critter
07-18-2011, 08:34 AM
Uh, well...

https://static1.pt-content.com/images/pt/2011/07/badhand-1.jpg

critter
07-19-2011, 06:16 AM
Crankshaft end play looks good:


https://static1.pt-content.com/images/pt/2011/07/crankendplay-1.jpg

critter
07-29-2011, 06:19 PM
Vacation is over. I had a great time visiting with my son and his family. Spoiling grandchildren is great fun!

Tonight I finished measuring rod journals. I had one, #5, that was a little tight at .0017 but some work with the green scotch-brite took care of that.

I moved on to rings after that. I couldn't get a good photo but the top ring gap showed .012 and the bottom compression ring showed .024. WTH? Since I bought these parts from a guy who had a shop assemble the bottom end and everything to this point has checked out well I was surprised. My standard has always been .004 X the bore size for final ring gap. So, .004 X 4.155 = .01662 so I round up and I get .017. That is very close to the .018 I've used in the past on the 455 engine's I've built.

I don't know who's rings these are so I'm going to contact the guy I bought them from and get a brand. Maybe I'm missing something.

Since that had by stopped for the moment I moved on to some detail work. I like to take 1000 grit sandpaper and wet sand the edges on the top of the pistons:

https://static1.pt-content.com/images/pt/2011/07/sanding-1.jpg

I don't know if you can see it here but look closely at the sharp edges of the valve reliefs. The idea is smooth them and avoid detonation. Since I'm running a very solid 9.5:1 compression ratio on this build I wanted to be sure I'm cool with this kind of stuff. The one on the left is not sanded. Hope you can see it:

https://static1.pt-content.com/images/pt/2011/07/edges-1.jpg

More when I find out about the rings.

Trevon
07-29-2011, 08:28 PM
Just read this whole thread again, looks like your not real far from having it together!

critter
07-30-2011, 05:03 PM
It appears a new set of rings are in my future. Four of the sets were usable but another 4 had bottom ring gaps larger than my largest .035 feeler gauge. Two of those 4 had top ring gaps over .024. Way too loose! I don't know if they had ring filing class that day at the previous machine shop. One side, the odd cylinder side, was consistent at .012 top gap and .024 bottom. The even side looked like a cross eyed amputee had filed them with his file in his teeth. They were filed at an angle and all over the place on the gaps.


Sigh.

f-body
07-30-2011, 05:36 PM
There has been a lot going on but not much time to post. Marty slapped on the torque plate and took it the extra .005 I needed. He said the bores looked good and finish he put on those cylinders is just so pretty!

I had some additional stuff to prep before really cleaning the block so I figured I'd get them out of the way now. First up was removing the passenger side galley plug that is hidden inside the block and drilling it .030 for an oil feed to the distributor gear. This is a common modification on Pontiac blocks to provide direct shot oiling to the distributor gear where it meshes with the cam gear. The first step is to remove (if it's not already out) the freeze plug in the block by driving it out with a drift. Next is to use a long Allen wrench to twist out that 3/8 NPT plug that's down under it.

I was going to mention something about lubricating the cam gear. I know you are dealing with a Pontiac block but chevy small blocks have a good fix also. The chevy distributor has this channel that fits the oil feed to supply oil forward in front of the distributor. The recomended fix is machine a small groove that will spray oil right on the cam and distributor gear where they mesh. I had changed to a stock type hydraulic roller cam and used a stock type distributor gear. I have excellent oil pressure but I inspected the oil pump prior to use. I also did tack weld the pickup on the pump cause I know the worst can happen. This engine is in my 1992 chevy truck daily driver. So far so good. The 1990 IROC heads and stock shortblock with new rings and bearings and the Vortec roller cam made a good combination. The V6 is gone and the 350 is a one piece rear seal block with low miles and standard bore. I did mill the heads just to clean them up and my compression comes in a 9.3:1. Its the little things that makes it all work.

I did clean the block really well like you did. If you have access to the hot water heater in the house you can do the final rinse with the drain on the hot water heater. Use a really good hose and gloves the water is really really hot, but it cleans and the hot water evaporates fast and prevents flash rust. It also cleans every last bit of oil off the block. I did blow air through all the passages to make sure i did not miss anything. After the block was clean and dry I went right to assembly.

Glad to see your build is going well. As soon as I get a few more miles on the engine I am going to Amsoil synthetic and thier filter. I currently use nothing but Wix filters.

My best friend had a 1972 Firebird Back in the late 80's. Here is how old the setup was. The engine was an RHS Pontiac 400 short block and he installed Ram Air heads that he ported and a 280 Comp cam hydraulic cam. That car was really fast and good combination. It had the entire Rancho suspension and sway bars. It was his daily driver for a long time. It was such a well put together ride. It was so streetable and so much fun to drive. I guess we were before our time with that car, fun, fast and steetable who would have thought you could have it all in one car. And now we have pro touring. Isn't it great. :)
Keep us posted on how the build turns out, look forward to hearing how much you like the new combination.

critter
07-31-2011, 11:34 AM
F-body, one day at a time brother. You can finish it. Just dedicate yourself to doing at least one thing a day, no matter how small.

It's been a frustrating weekend. I managed to find a Federal Mogul part number for the ring set I needed. I called a couple of local parts stores. One told me that I needed to go to a machine shop. The second said they would have to call their home office to cross reference the number and they'd get back to me on Monday.

And they wonder why I spend my money with Summit and Jegs? If they can't reference a make, model and year in that damned computer they just can't get it done anymore.

Trevon
07-31-2011, 06:53 PM
And they wonder why I spend my money with Summit and Jegs? If they can't reference a make, model and year in that damned computer they just can't get it done anymore.

I know how you feel there. I can go to a local store KNOWING what I need to buy, tell them, and they're like "Okay, what kind of car is it?" I reply a 1978 Trans Am, but thats not what the part I need is for... "oh..we don't have what you need."

Off to the internet, its rediculous! They even did that when I wanted a transmission cooler...really? They're all the same just different sizes!! So frustrating.

critter
08-05-2011, 06:03 PM
I know you all think I probably abandoned this build but I haven't. I was busy with a visit from my son and grandchildren plus being delayed waiting on a new ring pack to arrive. So back to business.

Gapping file fit rings is not the voodoo science that some might think. The ring manufacturer will usually include instructions with the ring pack regarding the end gaps and orientation of the rings. Just remember, loose is good and tight is bad. Loose means you might lose a little bit of cylinder sealing ability but tight means the end gaps might jam and break a ring land on a piston or worse.

The first step is to wash the ring packs down with some brake cleaner. If there's one rule on engine building it's to keep the crap out of the motor. Once that's done check the oil rings to be sure they're OK. Most pistons use an upper, scraper and lower ring in the oil rail. Some use a support ring that's supplied with the piston like the ones I'm using. The support ring has a bump or tab that fits the slot in the piston oil scraper ring just above the wrist pin. If those all check out, once you have them mounted you have a valuable tool. The rings that are critical are the upper and lower compression rings. Those are the "file fit" rings. But to get the gap properly set on those you need to be sure the ring is square in the bore. So the old hot rodders would push the oil rings around to get them protruding equally on all sides. Then you can insert the compression ring in the top of the bore and use the piston to push the ring down until the oil rails work as a stop. Viola! now your ring is square in the bore so you can measure the gap.

https://static1.pt-content.com/images/pt/2011/08/squaring-1.jpg

We will be using a feeler gauge to measure the gap. I try to size stuff so that when I slide the feeler gauge through that gap it has a slight drag.


https://static1.pt-content.com/images/pt/2011/08/gap-1.jpg

Now that the initial measurement is done the initial filing of the ring is done. There's one rule. You can take it off but you can't put it back. Go slow. Take of a little material and then put the ring back in the bore to measure. After a few you'll get the feel for it. So how do you file a ring? The best way is with a tool especially designed for this. But how do you do it if you're a guy in a garage doing a home build?

Get yourself a Mill file. This will have teeth that only cut in one direction. Do NOT use a diamond tooth file. We want all cuts to be made from the outside of the ring to the inside. This gives us the cleanest edge to the outside of the ring and the piston wall. The finer the teeth on the file, the better. Mount it in a vice, oil the file and then proceed to clamp the ring on both sides and file away. The edges will stay parallel and square!


https://static1.pt-content.com/images/pt/2011/08/ringfiling-1.jpg


Don't think you're done when you get those ring gaps just where you want them. You need to dress those sharp file cuts some way. It can be done with emory cloth, some 400 grit sandpaper or my personal favorite, an emory board from the wife's manicure set. :)


https://static1.pt-content.com/images/pt/2011/08/dressing-1.jpg


Before you install those rings be sure the ring grooves are clean as a whistle. There are a couple of ways to get rings on a piston. I usually walk them on but I see where the ring manufacturers are not recommending that these days so I thought I'd show the acceptable way to do it. Use a ring expander tool like this to spread them and drop them in the ring grooves.

https://static1.pt-content.com/images/pt/2011/08/ringexpander-1.jpg

More to come.