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MrQuick
09-30-2007, 11:35 PM
Remember the saying " you get what you pay for?

Well an $18 drive shaft almost cost me an engine.

I had a failure at the Goodies show over the weekend. Was caused by a cheap oil pump drive shaft shearing off an the dual prongs to the distributor shaft connection.

I pulled the pan this morning along with the mains and a couple of the connecting rods and all looked good.I will pull the rest tomorrow. Cylinder bores, camshaft and lifters are cherry.

I also found a summit stamped high volume oil pump...car is equipt with a stock pan.

Im quoting Monk " Here's what happened".

Friday afternoon while driving down to the shop, I was tailed by a guy on a nice Harley, he pulled besides me and gave me a nod, then motioned his hand as to say TURN IT UP? So I nailed the throttle and it pulled hard to 65 mph, it went from 3200 rpm to 5800 in an instant.

I think that might have been the last straw. Cause earlier I did a nice burner at work for the boss when leaving and up the street the distributor spun around and killed the engine. I assumed it was a loose hold down bracket. I then tightened it but it was loose again when I got to the shop.

The high volume pump sucked the pan dry long enough to cause the pump to seize and fracture the driveshaft. Then as Allen drove it to the show it might have broken further and then finally fail as he started it for the last time. Luckily he identified a problem and shut it down fast.

An early indication was the distributor movement should have been a clue, but it wasn't untill Allen mentioned that the idle had gone up and he was hearing a tick noise, then a second later the oil pressure dropped...We knew it was oil pump related.


But that doen't really explain the distributor movement does it? A siezed distributor shaft would cause a break at the gear pin or teeth. I checked the shaft and there are no signs of galling.

Your thoughts.....

HILROD
10-01-2007, 12:17 PM
Take the pump apart and check for debris. Also check the distributor over well. I've had the distributor mounts machined too low in the manifold causing binding, on the shaft. If this is the case for you, it could have bound the pump. You can look at the drive gear pattern to see if you'd need to raise the distributor, or lower the pump.

MrQuick
10-01-2007, 10:01 PM
Yep, I found that the pump gears where toast. No bearing damage to speak of. Thankfully he shut it off in time.