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Rod Bearing Replacement Results

 
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augidog  



Joined: 03 Mar 2003
Posts: 1360
Location: New Jersey

PostPosted: Tue Jul 05, 2005 10:40 am    Post subject: Rod Bearing Replacement Results Reply with quote

Rod bearing replacement was a piece of cake not counting the whole" Pan Removal Trip to Hell and Back" deal.
Here is my #4 rod bearing compared to another from a different cylinder.
# 4 has always had lower pressure and It sounded like the knock was from this rod.(no road test yet)

It is worn about .005 compared to the rest.
Did I save a failing bearing or is there other trouble brewing?

I also have a oil leak thats pretty bad now in front below the oil pump.
I can't believe that new rubber gasket is leaking up front.
Has anyone ever have an oil gasket let go at this spot.
Oh,and with the new pan gasket I changed to full synth after running semi for 2 years.
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Mike924  



Joined: 12 Aug 2004
Posts: 2601
Location: IoW UK

PostPosted: Tue Jul 05, 2005 5:01 pm    Post subject: Reply with quote

The No 4 bearing is the one in the top of the photo, right?

The wear patterns look fairly normal to me. (Your car must have racked up quite a mileage by now?) OK, so there's some evidence of poor lubrication on the top bearing, but I think you caught it in time and I don't think it's a sign of anything else gone wrong, just general wear and age. Keep an eye on it though.

Do I understand that you changed the bearings with the engine in the car?

(My car has a slight leak from the oil pump - makes a mess of the radiator bottom hose )
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John Brown  



Joined: 07 Nov 2002
Posts: 903
Location: Leesburg VA

PostPosted: Tue Jul 05, 2005 9:06 pm    Post subject: Reply with quote

Not horrible. But more than normal wear; from the picture it appears the top layer was starting the flake. But I'd guess your crank is probably still OK. If the crank checks visually OK then you're good to go.

Pan seals are like that , yes they are. Practice makes perfect!
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924RACR  



Joined: 29 Jul 2001
Posts: 9069
Location: Royal Oak, MI, USA

PostPosted: Tue Jul 05, 2005 9:48 pm    Post subject: Reply with quote

Yes, you need a good bit of good gasket sealant in my experience to make that thing seal. Best thing found yet is a copper-coloured gasket sealer RTV silicone product from Elring (the gasket company) called Dirko. My pan doesn't leak anymore, always used to with Permatex's RTV silicone.
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Joes924Racer  



Joined: 03 Nov 2002
Posts: 11964
Location: Oregon, Denver Colorado native!

PostPosted: Wed Jul 06, 2005 12:52 am    Post subject: Reply with quote

I got mine to seal up without anything added. .. though
I rememebr the time when i pinched
the rear rubber gasket and a 1/2 piece broke off resultng losing
all the oil on startup...you know doin the pan job with the motor
in the car is kind of tougher thats what I found to be true anyways.
good luck & good job.
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-nick  



Joined: 16 Nov 2002
Posts: 2699
Location: Cambridge, MA

PostPosted: Wed Jul 06, 2005 2:48 am    Post subject: Reply with quote

I'm guessing the bottom bearing is the bad #4 bearing? The top coating has worn off and it's down to the copper colored stuff. Definitely time to replace! You probably caught it just in time, I don't think they like to run on the copper colored material for very long.

It looks well grooved also? Was the journal perfectly smooth to touch for #4? If so, you're fine, if not, it needs turned and the new bearing won't last very long.

I learned this the hard way the first time I put an engine together at 16...

PS- I always use hylomar permatex for all my gasket. It's the best I've found. Stays soft and you can reuse your paper gaskets. I smear a thin layer over every gasket.

nick
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Slam  



Joined: 07 Jan 2005
Posts: 1689
Location: Wainwright, Alberta, Canada

PostPosted: Wed Jul 13, 2005 2:19 am    Post subject: Reply with quote

Hey, augidog, how bad was your knock before you changed the bearings? What did your oil look like? Gracie's 931 is knocking like mad and we're gonna do the rod bearings and hope that fixes things.
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MAD-924  



Joined: 05 Apr 2003
Posts: 55

PostPosted: Wed Jul 13, 2005 2:41 am    Post subject: Reply with quote

Yes, Hylomar, great stuff. I've used this stuff alot with great results including on my non-leaking oilpan. However I don't remember using anything on the front and rear rubber seals- it's been awhile though.
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augidog  



Joined: 03 Mar 2003
Posts: 1360
Location: New Jersey

PostPosted: Wed Jul 13, 2005 8:23 am    Post subject: Reply with quote

Slam wrote:
Hey, augidog, how bad was your knock before you changed the bearings? What did your oil look like? Gracie's 931 is knocking like mad and we're gonna do the rod bearings and hope that fixes things.

It was bad. But I only heard it under load. or above 3000 rpm.I have better oil pressure now. A small leak from my oil pump gasket now turned into a large one.
I would like to think the rod bearing caused the knock but I also found a loose screw in the pan. The engine sounds real nice now.
Good luck on Gracie- She won't give up that pan without a fight.
The rod bearings are ez once your there, they slide right out. I'm curious to see what yours look like.I also loosened and re-torque the mains.
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Gram  



Joined: 08 Feb 2005
Posts: 357
Location: Northland, New Zealand

PostPosted: Wed Jul 13, 2005 9:00 am    Post subject: Reply with quote

Did you take a look at the mains while you had the pan off..?
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Joes924Racer  



Joined: 03 Nov 2002
Posts: 11964
Location: Oregon, Denver Colorado native!

PostPosted: Wed Jul 13, 2005 9:50 am    Post subject: Reply with quote

You cant take a look at the mains with the crank still in
well I guess you could look at the cap side .. if thats enough..
hmmm maybe someone wants to tell a story of how they hulked
the crank out with the block still in the car to get to the main bearings
Youd have to make a special crank holder that fits on a jack to get it
down so you could pull the mains.. Ive replaced pistons and rod bearings in the car twice each time doing one & the other the next time. If
you ever want to pull the motor and dont have a motor puller just tear it down to the blockthen straddle it and pull it off the bell housing. Putting it in
is just the reverse I can do it thats cause Im a hulkster.
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Last edited by Joes924Racer on Thu Jul 14, 2005 5:17 am; edited 1 time in total
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augidog  



Joined: 03 Mar 2003
Posts: 1360
Location: New Jersey

PostPosted: Wed Jul 13, 2005 11:20 am    Post subject: Reply with quote

Hey Joe,
Do the rods just pull out?
I would pull the crank and do the bearings if it was possible.Is the flywheel easy to come off with just the oilpan off.
Did you break in your new rings correctly?
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kaffine  



Joined: 13 Jun 2003
Posts: 644
Location: Las Vegas

PostPosted: Wed Jul 13, 2005 12:54 pm    Post subject: Reply with quote

You wont get the flywheel off without pulling the trans or the engine the clutch has to come off to access the bolts holding the flywheel to the crank.

The flywheel doesn't have to come off to do the main bearings though. You should be able to slide the top bearing around to remove it. I will say I haven't done it on a 924 and german engineers have ways of making life difficult but it should be possible.

The rods will come out from the top of the block with the piston. It is preferable that the head be removed first otherwise alot of damage will occur
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Joes924Racer  



Joined: 03 Nov 2002
Posts: 11964
Location: Oregon, Denver Colorado native!

PostPosted: Thu Jul 14, 2005 5:20 am    Post subject: Reply with quote

mains are stout anyways.. I wouldnt want to try to replace the mains
this way with the flywheel attached no=sir ited be tough at best.
Augidog did a good job.
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