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acamato
04-27-2009, 10:41 AM
The motor in my 02 SL2 seized due to lack of oil. This past weekend I dropped the oil pan to take a look. I spun the #3 Rod bearing. The main bearings look OK, some scoring. The other rod bearings showed signs of lack of oil. The journals look good, a little discolored, but cannot feel anything with my fingernail. The #3 piston journal need to be cleaned up. It has some melted bearing stuck to it. And advice on trying to get this clean? I was going to try a plastic scraper. Any other Ideas.

I want to replace the main & rod bearings.

Can I replace the main bearings with the crank in the car?
Do I need to replace the oil pump?

I have post photos in my gallery.

Thanks in advance.

Highmile
04-27-2009, 11:34 AM
This is not a job I'd attempt with the motor in the car.

The biggest problem I see is that the rod in which the bearing spun should be replaced. To do it you will have to pull the head, at that point you'd be time ahead to pull it. I'd also have the crank polished/checked by a machine shop.

Since this was an oil issue, you should also check the cam and cam journals. Cast iron spinning in aluminum without oil gets ugly pretty quick.

Oil pump replacement, depends on what it looks like. Your repair manual will show you how to check it. It's worthwhile to replace the pressure relief valve too. It's a cheap part and best installed by a machine shop or dealer.

Above and beyond anything you need to identify why the oil issue to begin with. Otherwise you'll be right back in this boat.

Good luck

acamato
04-27-2009, 01:08 PM
I don't think the bearing spun for a long time. The motor never knocked. It just died. There were very little shavings in the oil pan. There were some on the windage tray. I cannot tell a difference in surface finish between the connecting rod caps. So, I think the damage to the rod is minimal.

The oil level dropped from burning and leaking from the oil pan. I don't drive this car. My wife told me we need to change the oil because the oil light is on. I thought she meant the change oil light. I was wrong.

My plan is to clean the journal and install new bearings. I can do this for less that $100 vs. $875 for a used motor.

OldNuc
04-27-2009, 01:19 PM
Any shavings means the engine should be removed and rebuilt after being dipped. Any less than that is risking a prompt catastrophic failure after reassembly.

acamato
04-27-2009, 01:54 PM
Any shavings means the engine should be removed and rebuilt after being dipped. Any less than that is risking a prompt catastrophic failure after reassembly.

I am well aware of the risk of not tearing down the motor. I want to spend minimal $$ of this car. I don't want to invest the $1000+ it would cost to rebuild the motor or replace it with a used motor. I can replace the bearings for under $100.
If the spin another bearing, It was a $100 gamble. The car is used to get back and forth to the train station which is 1 mile from my house.

OldNuc
04-27-2009, 03:05 PM
You can roll the upper shell in if you loosen all the caps. Plastic scraper is probably what it will take to get the fused lead off of the rod journal. Oil pump is in the timing cover so unless you want another mean job better hope its chip free.

acamato
04-30-2009, 09:51 PM
Today, I got the car running. I replaced the rod & main bearings with the motor in the car. :)

Cleaning the the melted aluminum from the bearings off the crank journal for the #3 rod was time consuming. I tired a plastic scraper (did not work), I razor blade worked pretty good the get some of the metal off. I had to keep it at a sharp angle to ensure that I did not mark up the journal. I also used a fine brass wire wheel. That worked the best, it got the journal nice & clean. I also used green scotchbrite of remove some of the discoloration & to ensure that there was no metal buildup on the other rod journals.

After I had the journals clean I sprayed the whole area with brake cleaner to wash away any metal particles that may be in the bottom end.

I installed the new bearings using assembly lube. I also had the valve cover off and poured the oil over the cams before I put the cover on. I cranked over the motor with the plug wires off until the oil light went out. I then put the wires on and started it up. It sounds great, no knocking...

I will change the oil & filter after a few hours of running.

almoore
05-21-2009, 11:49 AM
I have to do the same thing.Do you have any advice you can share?

rc1488
05-21-2009, 12:57 PM
I have to do the same thing.Do you have any advice you can share?

He was lucky. When the rod bearing goes, it creates alot of heat on the crank...and can thus warp the crank.

Its best to remove the crank and have it inspected. If it checks out ok, have the machine shop clean it and tell you what bearings to get. The rod that had the spun the bearing should also be replaced.

Again...he was lucky. If i did what he did I would have put a warped crank back into the engine....and Failed.

bjcart
05-21-2009, 01:10 PM
Yep, extremely lucky. Previous owner spun the #2 rod bearing on my '94. Crankshaft and #2 rod are completely destroyed.:yes:

By the way, anybody have a good crank they want to sell me?:p

rc1488
05-21-2009, 01:16 PM
Yep, extremely lucky. Previous owner spun the #2 rod bearing on my '94. Crankshaft and #2 rod are completely destroyed.:yes:

By the way, anybody have a good crank they want to sell me?:p

I bought mine from C&P Machine. They sent a remanned cranked with bearings (rod and main) ready to be dropped in. About $200. I went this route bc i wouldnt have to worry about what bearings to get and such. It all came matched up. GREAT customer service. Just ask for Brian.

Otherwise Lowsaturn has some. But they need to be inspected, cleaned, and then the machine shop will need to tell you what bearings to get.

I also have an extra rod if you need it :)

skii33
05-22-2009, 05:41 PM
100% chance that if you spin a rod bearing it oblongs the rod journal . It may look good but we are talking just a couple of thousands of an inch that the rod bearing goes out of round. You can have it resized at a machine shop for just 8-10 dollars. I'll bet the crank needs grinding also.The extra work pulling the head to remove the rod and piston would have been good insurance....My advice to anyone who spins a rod .....DON"T shortcut , it will just bite you in the end ......TRUST ME , i have built plenty of saturn (and other engines) thanks Glenn

OldNuc
05-22-2009, 09:15 PM
+1^^^^^You are not going to get away with just stuffing in another bearing.

medarwin
07-31-2014, 06:41 AM
Hi, Following up to see if there was any long term downside to the bearing repalcement job with the engine still int he car. Looking at doing a similar, I have a 99 SW that needs new crank bearings. I want to give it to my 16yo for a starter car and egngage him in the project.

Thanks, Darwin



Today, I got the car running. I replaced the rod & main bearings with the motor in the car. :)

Cleaning the the melted aluminum from the bearings off the crank journal for the #3 rod was time consuming. I tired a plastic scraper (did not work), I razor blade worked pretty good the get some of the metal off. I had to keep it at a sharp angle to ensure that I did not mark up the journal. I also used a fine brass wire wheel. That worked the best, it got the journal nice & clean. I also used green scotchbrite of remove some of the discoloration & to ensure that there was no metal buildup on the other rod journals.

After I had the journals clean I sprayed the whole area with brake cleaner to wash away any metal particles that may be in the bottom end.

I installed the new bearings using assembly lube. I also had the valve cover off and poured the oil over the cams before I put the cover on. I cranked over the motor with the plug wires off until the oil light went out. I then put the wires on and started it up. It sounds great, no knocking...

I will change the oil & filter after a few hours of running.

OldNuc
07-31-2014, 07:00 AM
Hi, Following up to see if there was any long term downside to the bearing repalcement job with the engine still int he car. Looking at doing a similar, I have a 99 SW that needs new crank bearings. I want to give it to my 16yo for a starter car and egngage him in the project.

Thanks, Darwin

There is no easy way to accurately measure the crank and rod clearances with the crank in the engine. If the engine runs now without any unusual noises you can try it but do not be surprised if it is a failure.

SL19302
07-31-2014, 07:44 AM
I would think with even cleaning the failed journal, The finish on the crank would be all scored up from lack of oil, Installing a new bearing over a scored journal wont last, Along with that low oil levels starved the entire engine not just number 3 rod bearing, The oil pump im sure at this point would have excessive clearances causing low oil pressure at idle when the engine is hot...

billr
07-31-2014, 09:57 AM
"Medarwin", you scabbed-on to an old thread; did your engine also get low on oil and spin bearings??? Or is it just old, and you have some symptom like noise or low oil pressure or crank end-play that makes you suspect the bearings? If a bearing didn't get spun, then you are much more likely to have success just changing the bearings in the car. Plasti-gauge has been used quite successfully for many, many years to check bearing clearances; you can use that with the engine in the car. Tell us what symptoms you have here...

OldNuc
07-31-2014, 01:28 PM
You are not going to measure for out of round, taper or flat spots with plastigauge easily. You can get an idea of the general clearance.

billr
07-31-2014, 04:49 PM
^^^ True enough, plastigauge is not nearly as good as having the crank out for full inspection. That's why I hope the OP gives us more of the story. If the bearings are just worn, no reason to suspect damage to the crank, the taper and out-of-round are probably not going to be an issue. OP would just need to check clearance. It think the OP is looking for a practical approach here, no intent to "blue-print" the engine (or even a true rebuild).

DJKrohn
07-31-2014, 05:05 PM
I've tried the in-car method once. I cleaned everything up and plasti-gaged it, and got a new bearing from Saturn that was slightly bigger to fit (according to the plasti-gage measurements). I can't remember if it was under-sized, over-sized, or both, but I think it was .002". I installed it, and the clearance looked good, along with the other bearings. Started up the engine and drove awhile and the same rod started knocking again. Crank was probably out-of-round. For that reason, this method is probably never likely to succeed. But feel free to try it.

:hmpf: I hate taking off nasty oil pans in-car. And it's impossible to get them to seal perfectly, no matter how much time you spend and how much brake cleaner you use. There's always going to be a small drip of oil coming down inside the engine block to contaminate the RTV.

OldNuc
07-31-2014, 05:24 PM
^^^ True enough, plastigauge is not nearly as good as having the crank out for full inspection. That's why I hope the OP gives us more of the story. If the bearings are just worn, no reason to suspect damage to the crank, the taper and out-of-round are probably not going to be an issue. OP would just need to check clearance. It think the OP is looking for a practical approach here, no intent to "blue-print" the engine (or even a true rebuild).

Without more detailed information leading to why the bearings need replacement there is no way to even intelligently guess what will work. I have way to many cranks that came out of engines with reasonably low mileage that were just being overhauled based on run hours and the cranks were far from round even though the plastigauge did not indicate any problem. Taper and out of round are instantly obvious when the crank is chucked up in the grinder.