Is it possible to replace the timing cover on SBC w/o dropping the oil pan?

[SuperNova]

Re: Is it possible to replace the timing cover on SBC w/o dropping the oil pan?

How do you check the crank for end play with the engine in the boat. I have pulled up and down and sideways on the crank and can't get it to budge.

Pry it forward and back with a dial indicator mounted to read fore - aft movement

 

[RobOp]

Re: Is it possible to replace the timing cover on SBC w/o dropping the oil pan?

I really don't know anything about mercrusier/quicksilver remans but if i had to take a wild guess i would say that it is probably sub- contracted out... and everyone knows how that goes, low bidder.

There are several threads here discussing the 4.3 to 5.7 swap its not too bad. Ill see if i can find one. Ive never done it myself but may in the near future. Some things... starter, distributor, alternator, power steering, fuel pump, possibly carb all can be reused.

Accurately measuring the thrust clearance is probably not going to work unless its upside down with the pan off.

Here is a small video i found that shows how a crank can be broken and the engine still run. Ive seen it 2 times once on a 302 ford once on a 350 chevy.

http://www.youtube.com/watch?v=eCCwFo23s9o&feature=results_main&playnext=1&list=PL0B616572C6F6B92A

Id say at this point its time to pull it and tear into it.

Ug! I think you are right Joe, it's about time to bite the bullet... I've just sent Mercruiser customer support an e-mail detailing the problem and asking if they have records for part numbers on the crank, rods and pistons. If I can get those part numbers out of them I will try to reconcile the weights and compatibilities with data in the hotsixes link. Thank you for that!

I'll wait and see if they have anything to say.

 

[joewithaboat]

Re: Is it possible to replace the timing cover on SBC w/o dropping the oil pan?

Pry it forward and back with a dial indicator mounted to read fore - aft movement

Right, but you are trying to take a measurement that should be in the neighborhood of .005 of an inch. You could mount an indicator on the front of the engine to the balancer but what you gonna pry on.

 

[Pete104]

Re: Is it possible to replace the timing cover on SBC w/o dropping the oil pan?

It ain't like you can stand next to it!

 

[RobOp]

Re: Is it possible to replace the timing cover on SBC w/o dropping the oil pan?

Right, but you are trying to take a measurement that should be in the neighborhood of .005 of an inch. You could mount an indicator on the front of the engine to the balancer but what you gonna pry on.

Agreed! I see no value in trying to measure endplay with the engine in the boat. At this point I'm trying to find out if there is anything I can do to fix this thing without pulling the engine. I can't replace a thrust bearing with it still in the boat.

When I pull the motor out and tear it down hopefully the problem will be revealed.

 

[SuperNova]

Re: Is it possible to replace the timing cover on SBC w/o dropping the oil pan?

Right, but you are trying to take a measurement that should be in the neighborhood of .005 of an inch. You could mount an indicator on the front of the engine to the balancer but what you gonna pry on.

You're right, but before I went to the trouble of removing the engine to actually measure it, I would pry it back and forth on the balancer center. If crank endplay is causing the leak, the excessive endplay should be obvious. We are not talking about a spec of .005" and if we have .008" being the cause of the leak. If endplay is the cause it'll have to be a lot more than that. And anyway, endplay doesn't usually cause the seal to tear, it usually pushes the seal out of the timing cover. Seal tearing is usually a burr or poor installation. The slightest nick is all it takes.

 

[81 Checkmate]

Re: Is it possible to replace the timing cover on SBC w/o dropping the oil pan?

Wow lots of excitement on this thread. What a bummer new motor and cant go boating. It only makes sence as discribed by you that when under load the crank has a slight wobble and causing oil to spay out. You have done alot of testing to Determine this. As someone mention earlier. Have you tried to drill out the dowel holes on the cover before installation? That just might give you enough play. Who knows someone could have installed a oversized pin or hole was mach at a slight angle witch is throwing off your cover. I would also try a different brand of seal with your new sleeve. If it were me I would try again before pulling the motor.

Good Luck!