Its on a 1999 Pontiac Sunfire 2.2L. I have seached the fourms and cant come up with all the answers i need.
I spun a bearing on my #4 cylinder. So i dropped my oil pan and replaced the bearing with a new one and put it all back. There must be some play still on the rod beacuse anything after 2k RPM theres a slight knock. Not that bad tho. I went to Orileys to get an oversized bearing and they said they came in incriments of .001. How can i find out how much bigger I need?
Alot of people keep telling me that i need to pull the crank to measure the diffrence, or have the crank turned at a machine shop. I would much rather do a quick fix and not go through all that, but if i do is it possible to remove the crank throught the oil pan by removing all the rod ends? Also I am thinkin of just going .002 oversized and putting it in. what would happen if i get too big of a bearing? I am not going to be running this car hard at all. its not a race car i just want it to run a little smoother. anything will help!
Thanks!
-Paul
Your crankshaft is what you have to have turned first, BEFORE you install oversized bearings.
Thats the point of oversized bearings, to decrease clearance to specs, that was out of spec.
What your most likely going to have to do, is put all the same size bearings in there, and have the crank turned at the shop.
You cant have one part of the crank, one size and the other half a different size, your bearings will all be different sizes. the bearing to crank clearance, using plastigauge is .002 difference between them all, more than that, plan on the motor being shot
Otherwise I dont see that motor lasting to long.
Keep in mind, we are talking about being within .001-.002 here, otherwise your motor may be junk
- 2004 Cavalier - 124k, owned since new
Another thing, with the bearing being too big and you having run it like that, odds are the round end is now out of round, and it would either have to be machined true again, or outright replaced. Same with the crank journal. Might as well rebuild the bottom end.
Rob S wrote:Your crankshaft is what you have to have turned first, BEFORE you install oversized bearings.
Thats the point of oversized bearings, to decrease clearance to specs, that was out of spec.
What your most likely going to have to do, is put all the same size bearings in there, and have the crank turned at the shop.
You cant have one part of the crank, one size and the other half a different size, your bearings will all be different sizes. the bearing to crank clearance, using plastigauge is .002 difference between them all, more than that, plan on the motor being shot
Otherwise I dont see that motor lasting to long.
Keep in mind, we are talking about being within .001-.002 here, otherwise your motor may be junk
okay thanks. is it possible to get to the crank through the bottom of the engine? By removing the rod ends? would i have to disconnect the tranny also? Is it necessary to replace the rod while Im doing all this?
Well im in the same boat and i figgured i can get a rebuild kit for a little over 500 so thats what im going to do. But what happend to me is i had 2 spun bearings the front main and the #1 rod the crank is fubard.
My car--->
http://www.cardomain.com/ride/2569452
To get the crank out you most certainly have to have the tranny off, as well as the flyhweel/flexplate. It'd be easiest to yank the engine, and smartest to go ahead and rebuild the whole shortblock. Its a severe bitch to use plastigage with a 90-100 odd pound crank above your head. Plus you gotta worry about getting the rods aorund the journals, and holding up that crank with both hands leaves your feet to do the rods, and I dunno about you, but ,y feet don't do that sort of thing very well. haha. And like I said in my earlier post, the big end of the rod is almost CERTAINLY out of round, and MUST be machined true or replaced.
thanks bro you really know what your talking about. let you guys know how it goes im sure im gonna be back in here today or tomarrow asking more questions. mainly beacuse there arent any steps for this kind of thing in the chiltons manual i bought...
Nah man i saw the same thing there is NOTHING about taking apart the bottom end of our engines. Don't know why though but it is pretty easy the only thing i need is the torq specs for the rob bolts and main bolts.
My car--->
http://www.cardomain.com/ride/2569452
96 cav wrote:Nah man i saw the same thing there is NOTHING about taking apart the bottom end of our engines. Don't know why though but it is pretty easy the only thing i need is the torq specs for the rob bolts and main bolts.
Rod bolts:
Tighten the connecting rod bolt nuts to 52 N-m (38 lb ft).
Loosen the connecting rod bolt nuts 1 full turn
tighten the connecting rod bolt nuts to 52 N-m (38 lb ft).
Main bolts:
Tighten the crankshaft bearing cap bolts first to 50 N-m (37 lb ft).
Before installing the rear crankshaft main bearing cap, coat the face of the block where it mates to the cap with sealer GM P/N 1052942.
Measure the crankshaft end play (note from me, this is ESPECIALLY critical on manual transmission equipped vehicles) using the following procedure:
firmly thrust the crankshaft rearward.
Firmly thrust the crankshaft forward.
This will align the crankshaft bearing and the crankshaft thrust surfaces.
Tighten the rear crankshaft bearing cap bolts to 96 N-m (70 lb ft).
Measure the crankshaft end play at the front end of the rear crankshaft bearing with a feeler guage.
The crankshaft should still be wedged forward.
The proper clearance is 0.0511-0.1780mm (0.002-0.007 in).
Hope that helps. BTW that note was put there because when you engage/disengage the clutch, the pressure from doing that will transmit directly to the thrust bearing surface on the crank. That clearance is therefore VERY critical on manual transmission equipped vehicles.
I got this info from my Helm guide. Its for the 2200 OHV engine, I would assume the torque specs 2.2 OHV on the older J-bodies is the same in this case.
Edited 1 time(s). Last edited Saturday, July 07, 2007 11:37 PM
