How Hard to Replace Rod Bearings?
Thread Starter
Drifting
Joined: Nov 2002
Posts: 1,455
Likes: 2
From: East TN
How Hard to Replace Rod Bearings?
I thought it would be a good idea to replace the rod bearings before putting in my hot cam since the engine has 150k on it. I have a kwiklift so getting under the oil pan won't be a problem. Any special tools or experiece needed to do this... how long should it take for a first timer?
Team Owner
Joined: Jan 2003
Posts: 20,306
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From: Summerland B.C. Canada
Iv'e never tried with the engine in the car but as long as you have full access to all the rods, it should be doable. Get some plasti gauge to see what size bearing will be required. Be sure to put tubing over rod bolts during re and re. I would say a couple of hours for the project. 
Racer
Joined: Jan 2005
Posts: 315
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From: tomahawk wisconsin
if your going to do rod bearings then you might as well go with new rings and mains because you do have alot of miles on it.you better use a mike and see if your journels are worn out too. you might have to get your crank turned.
Le Mans Master
Joined: Oct 2003
Posts: 6,130
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From: seattle WA
I've done it several times (on different cars) but I also replaced main bearing too.Your there-why not. With that many miles, do make sure the crank journals are still in good condition. Just be careful-and do use tubing on the rod bolts, you will need to rotate the crank shaft while doing this-so it's very important to protect the journals. You'll
need a good torque wrench. BUT if I were you I'd do a compression
test first to see what condition the rings and valves are in. I always
just made sure the bearing surface had a good coat of oil on them before I installed.
need a good torque wrench. BUT if I were you I'd do a compression
test first to see what condition the rings and valves are in. I always
just made sure the bearing surface had a good coat of oil on them before I installed.
Last edited by rick lambert; Mar 5, 2005 at 10:38 AM.
Drifting
Joined: Oct 2003
Posts: 1,594
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From: CALGARY ab
Originally Posted by dan6712cc
So a Crafstman torque wrench wont cut it for this job? I was thinking about getting a snap on, looks this would be a good time to get one 
upon removing caps check crank for any signs of damage..plastiage all bearings before and after..lube the bearings well with assemble grease.
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Le Mans Master
Joined: May 2004
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From: Hellinois
Finalist 2020 C4 of the Year - Modified
I've never used any torque wrench except a Craftsman and I've built quite a few engines. I'm going to give you some good advice, if your modiying a 150,000 mile engine do it right, pull the engine, take it apart, have it hot tanked and all machine work done to the block, crank and heads. If not you're going to end up with a broken engine, then it'll be time to spend BIG $$$. You just don't mod a tired engine. This is my opinion only FWIW.
Thread Starter
Drifting
Joined: Nov 2002
Posts: 1,455
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From: East TN
Originally Posted by Midnight 85
if your modiying a 150,000 mile engine do it right, pull the engine, take it apart, have it hot tanked and all machine work done to the block, crank and heads.
Safety Car
Joined: Dec 2002
Posts: 3,655
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From: Charleston SC
LOL,
This sounds like a situation I would get my self into. Hmmm, I think I will do a simple cam swap but wait, 5K later a rebuilt motor. My sugestion is to leave the bottom end as is and start saving money to rebuild the motor the right way instead of tring to prolong the existing high mile motor. The LT1 is a great motor and you could see many more miles before you have any major problems. Plan on spending a min of 2.5 K for a stock rebuild with a good valve job if you build it yourself. I have yet to build an LT1 without spending twice my original goal so I am not the best source so if you rebuild on a budget try to avoid the "while I am here" situations.
This sounds like a situation I would get my self into. Hmmm, I think I will do a simple cam swap but wait, 5K later a rebuilt motor. My sugestion is to leave the bottom end as is and start saving money to rebuild the motor the right way instead of tring to prolong the existing high mile motor. The LT1 is a great motor and you could see many more miles before you have any major problems. Plan on spending a min of 2.5 K for a stock rebuild with a good valve job if you build it yourself. I have yet to build an LT1 without spending twice my original goal so I am not the best source so if you rebuild on a budget try to avoid the "while I am here" situations.
Race Director
Joined: Sep 2000
Posts: 17,298
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From: The Top of Utah
Originally Posted by Midnight 85
I've never used any torque wrench except a Craftsman and I've built quite a few engines. I'm going to give you some good advice, if your modiying a 150,000 mile engine do it right, pull the engine, take it apart, have it hot tanked and all machine work done to the block, crank and heads. If not you're going to end up with a broken engine, then it'll be time to spend BIG $$$. You just don't mod a tired engine. This is my opinion only FWIW.
Absolutely!Changing rod bearings is a "patch job". What are you trying to correct? I've done it on a MUCH lower mileage engine. When THAT didn't solve my problem, I pulled the pan again and changed the mains. Regardless, it is a stop gap, patch job, operation. If the engine isn't healthy enough to modify, which is likely at 150,000 miles, wait. If down time is an issue (you mentioned that), pick up a core, build up an engine, and do a swap. That is how I have always handled my own rebuilds. Just like the money budget gets exceeded, so does the time budget.
RACE ON!!!
Race Director
Joined: Feb 1999
Posts: 12,772
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From: Indianapolis IN
Did it a couple of months ago, engine in the car,, no biggy, once the pan is off, just make sure you get a pair of feeler gauges to gap the rod spacing so you dont tighten the bolts and get the cap a little skewed, you wanty to spacing to be equal.
Also, clean the doodie out of everything and apply some oil or assembly lube to the caps.
Also, clean the doodie out of everything and apply some oil or assembly lube to the caps.
Advanced
Joined: Oct 2004
Posts: 70
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Originally Posted by CFI-EFI
Absolutely!Changing rod bearings is a "patch job". What are you trying to correct? I've done it on a MUCH lower mileage engine. When THAT didn't solve my problem, I pulled the pan again and changed the mains. Regardless, it is a stop gap, patch job, operation. If the engine isn't healthy enough to modify, which is likely at 150,000 miles, wait. If down time is an issue (you mentioned that), pick up a core, build up an engine, and do a swap. That is how I have always handled my own rebuilds. Just like the money budget gets exceeded, so does the time budget.
RACE ON!!!
This is a no brainer. You will be soooo much more satisfied with the peice of mind in doing it right.
Drifting
Joined: Aug 2001
Posts: 1,407
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From: Houston TX
Originally Posted by ar91c4
if your going to do rod bearings then you might as well go with new rings and mains because you do have alot of miles on it.you better use a mike and see if your journels are worn out too. you might have to get your crank turned.
Pro
Joined: Aug 2001
Posts: 617
Likes: 14
From: Loudon, TN
You're going to be wasting time and effort doing what you are talking about. All the bearings, mains and cam bearings are just as worn as the rod bearings so just replacing the ones for the rods makes no sense. 150K is a lot of miles on an engine no matter how well it has been maintained especially when you want to do something that will cause more strain on it than normal. Save your money and do it right all at one time.
If either of the shops in your town rebuild engines, they should be able to handle a Chevy 350 with no problem. There is nothing more exotic or technical about a Corvette's 350 than one in a Camaro or Caprice. Now if you had a Lambo or a Ferrari then I would have concern about a local shop having the expertise and tools to do the job.
If either of the shops in your town rebuild engines, they should be able to handle a Chevy 350 with no problem. There is nothing more exotic or technical about a Corvette's 350 than one in a Camaro or Caprice. Now if you had a Lambo or a Ferrari then I would have concern about a local shop having the expertise and tools to do the job.
Thread Starter
Drifting
Joined: Nov 2002
Posts: 1,455
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From: East TN
Seems like alot of people think theres a good chance of spinning a bearing by putting in a new cam in an engine with this many miles... I've also read a few posts that disagree.. so has anyone here actually spun a bearing doing this or is this more of a rumor for our LT1s? If you did how many miles were on your LT1 and how well was the engine taken care of? Also how many of you have replaced the cam with a high mileage engine and not had a problem?
I've had the car for the last 80k miles and have aways replaced the oil every 3-3.5k miles with Mobil 1 synthetic and hardly ever get on the gas (daily driver). There was one exception with Penzoil
The first 70k miles had one owner and don't know what the history is on that. I had an intake manifold gasket replaced in 2001 and no other engine problems since then.
I've had the car for the last 80k miles and have aways replaced the oil every 3-3.5k miles with Mobil 1 synthetic and hardly ever get on the gas (daily driver). There was one exception with Penzoil
The first 70k miles had one owner and don't know what the history is on that. I had an intake manifold gasket replaced in 2001 and no other engine problems since then.
Last edited by dan6712cc; Mar 6, 2005 at 10:41 PM.
Safety Car
Joined: Dec 2002
Posts: 3,655
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From: Charleston SC
I personaly don't like the idea of puting a cam in a high milage motor but its your call. I have personaly seen two post on spun mains after a cam swap but not knowing how clean the parts where kept there is no way to know what the cause of the failure was. My truck has 250,000 miles on it and is still going strong, It may not be an LT1 but it is a 350 none the less. Good luck in what ever your desision is but new mains will not help if you get contamination they will spin just as fast as the 150,000 mile ones.
Thread Starter
Drifting
Joined: Nov 2002
Posts: 1,455
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From: East TN
Originally Posted by FD2BLK
I personaly don't like the idea of puting a cam in a high milage motor but its your call. I have personaly seen two post on spun mains after a cam swap but not knowing how clean the parts where kept there is no way to know what the cause of the failure was. My truck has 250,000 miles on it and is still going strong, It may not be an LT1 but it is a 350 none the less. Good luck in what ever your desision is but new mains will not help if you get contamination they will spin just as fast as the 150,000 mile ones.