Engine Seized - Now What???

[Chevelle LT1]

As the title says, the euphoria of having my car running for the 1st time in years lasted for a very brief 10 seconds before the engine stopped....and hasn't been able to turnover since. I did the obvious of adding oil before starting, and turning the engine over by hand/with the starter (and plugs out) and saw oil pressure registering on the gauge. However, the second I started the car, the oil pressure gauge went to 0, and I got a total of 10 seconds run time before the car quit on me. There were no abnormal noises, etc., before the engine quit, but I am a bit stuck as to what to do next.

The engine is an LQ9 with a new oil pump, LS3 heads, and camshaft. Any suggestions for something obvious to check before the engine is pulled and sent off to someone else to check out. On a related note, anyone know a good builder/machine shop in the Phoenix area???

Needless to say, a definite bummer...

~ Jason

[Reckn8]

We've had nothing but the best when working with Duffee Motorsports in Glendale. www.duffeemotorsports.com

[Chevelle LT1]

Paul - Many thanks for the reference. If you've had good past experience with them, I will definitely give them a call.

Thanks again.

~ Jason

[Rhino]

Does th motor spin over freely by hand? Does the starter attempt to turn it over? Was it an abrupt stop or was it similar to turning the key off?Last motor I built had 0 oil pressure for a solid 10 seconds before shooting up. With the pump and the front and the sump in the rear, these motors have extremely long pickups. Unless something else was wrong I can't see the lack of pressure on startup causing this issue.The lack of indicators leads me to think you may have a wiring/PCM issue.

[Kenova]

If you can't turn it over by hand, remove the starter motor and try again.
A jammed starter drive can lock an engine up solid and no amount of push starting in any gear will turn it over.:banghead:

Ken

[jwcarguy]

Also, after checking the above options, which hopefully it is just something simple?

When you rebuilt the engine did you replace the "barbell" oil diverter in the rear oil gallery (under the rear cover, replace the front oil gallery plug (under the timing cover) and did you install both the correct size oil pickup tube o-ring to pump (there are two sizes, depending on pickup tube type) and install it correctly (squarely and not pinched)

[Chevelle LT1]

Thanks guys. Removed the starter last night and no change to motor rotation (still stuck). Drained theo oil pan and saw no metal shavings/evidence whatsoever, so it is definitely coming out to have somebody more knowledgeable than myself diagnose it.

[jwcarguy]

Who assembled the engine?
Did it turn over, completely 360 degrees by hand, prior to installing it?
What type of cam retainer plate did you use? The old style had (4) 10mm male headed bolts holding it down, the new redesigned style has (40 countersunk female torx headed bolts
Problem is, that when people do cam swaps and use the old style plates/ bolts, most don't realize that there are two different length bolts out of the 4! ( by approx. 1/8")
the two shorter bolts are used in the top & bottom plate locations and the two longer bolts are used in the right & left side locations

I had a guy bring me a LS1 shortblock to complete the topend install and was supposed to install cam & lifters, but the cam was already in it/ He said that his brother put it in for him?
Besides the fact that he had the timing marks no where near correct, when checking over the bottom end, I could only rotate the crank 180 degrees, then it would stop hard??
After awhile of going over everything, that is when I saw the end of the bolt just barely poking out of the block and into the way of the front counterweight on the crank!

Maybe something else to check?

The engine shouldn't have been able to get that hot and lock up in only 10 seconds of running


Jeff

[Chevelle LT1]

Jeff -

Thanks for all the ideas. In this case, then engine was a complete pull-out from the junkyard, and I added the new cam and oil pan/pickup, along with the LS3 heads and intake. All told, it seems like pretty minimal changes for the problems I am having. Nonetheless, the engine was dropped off with Duffee Motorsports today, so I'm keeping my fingers crossed it is something relatively simple (i.e., cheap).

I'll report on the prognosis early next week, if the planned teardown schedule holds.

Cheers

~ Jason

[Chevelle LT1]

Just a quick update: Machine shop called and the thrust bearing is what seized (said lack of oil). That repair wouldn't be so bad, but it turns out the engine I purchased from the junkyard had the snot beaten out of it in a past life, and needs a full rebuild at 50k miles. Now, how to explain this to the wife....