Can you replace rod bearings with engine still in car?

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swagster

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I called on a 73 Duster with a 360 in it and a 904 trans. He said it will need rod bearings eventually. My question is...could I change the bearings by just dropping the pan with the engine still in the car? I've done this before in trucks but I'm not sure about these. Thanks!
 
Yes it can be done. Motor has to be lifted up maybe 2",centrelink is in the way so get it out. You will of course need to put the vehicle up on jackstands and drain the pain.

If you still have an engine to trans brace,take the driver side brace out.

If you have a Y pipe on your exhaust it will need to be cut out.

Oh first remove the dipstick and disconnect the batt.

Then it's just a matter of replacing the bearings.
 
I say, NO. Yes, you can crawl under there, get "all oily" and get the bearings out and back in.

But that does not make it RIGHT

If the rod bearings are worn, the crank probably is, too, and some of the rods may have been "pounded out."

I say, if an engine needs rod bearings, it needs to come out

Inspect it, clean the oil system out, mike the entire crankshaft, mains and rods, and go from there. Pull the pistons / rods and have the rods checked (minimum) for out-of-round, I.E. have them reconditioned.

In this day and age, unless an engine was really run hard, as in raced, the rod bearings should last as long as anything else, generally speaking. So the question IS, "why just the rod bearings?"
 
Yep thats the "correct" way to do it. But I've also seen backl=yard fixes go 30 000 miles..
 
I did it to an old Pontiac something or other back in High School. It stopped knocking and ran good for years. If you dont mind getting oily, go for it.
 
I've done it in my '98 Ram 1500 5.2, and last weekend I did it in my '71 Swinger 318/904.

Once you have the pan off, it isn't that big of a deal. I always change them one at a time so the caps don't end up on the wrong rods. Be sure to remember which direction the caps came off (the caps and rods are usually punch-numbered 1-8 on the same side), make sure the bearing shells are installed correctly with the oil holes in the same orientation as the old bearings you take out, and the reliefs in the bearing shells fitting into the reliefs on the cap and rod.

If you turn the crank by hand after removing each cap, you can pull the rod/piston down and swing the rod end around to the side of the block. This makes it easier to inspect, clean, and snap in the bearing shell. Smear a good coat of quality assembly lube onto the bearing surface and the crank journal, (I use Lucas). Next, push the rod/piston back up and into position, then pull it back to the crank making sure the rod bolts don't nick the journal. Smear the bearing on the cap with assembly lube, then torque the bolts to 45 ft.lbs.

Crank the engine by hand after installing each bearing to be sure nothing is tight. If the crank turns harder than before you installed the bearing, something is wrong. Don't continue until you find the problem!

Remember to prime the motor with a drill before starting it.

Call me crazy, but both times I've done this I warmed the engine up, then revved it to 5500-6000 RPM... just to test my work, I guess. Haven't chucked a rod yet! :thumrigh:
 
I do agree with 67 Dart but in car overhauls have been done forever with good results. I had low oil pressure on my 6.5 diesel in my tool truck and I had new bearings slid in and a new oil pump installed. That was 75,000 miles ago. Still no problems. oops, bad luck....I hope it doesn't blow up tomorrow! LOL
 
67Dart273 said:
I say, NO. Yes, you can crawl under there, get "all oily" and get the bearings out and back in.

But that does not make it RIGHT

If the rod bearings are worn, the crank probably is, too, and some of the rods may have been "pounded out."

I say, if an engine needs rod bearings, it needs to come out

Inspect it, clean the oil system out, mike the entire crankshaft, mains and rods, and go from there. Pull the pistons / rods and have the rods checked (minimum) for out-of-round, I.E. have them reconditioned.

In this day and age, unless an engine was really run hard, as in raced, the rod bearings should last as long as anything else, generally speaking. So the question IS, "why just the rod bearings?"
Click to expand...

I've replaced them successfully twice (as described in my previous post), but I also did a 360 that had a rod knocking in a '73 Fury about 10 years ago, in an attempt to limp the car home. It was quiet for about 70-80 miles, then it spun the bearing again.

IF THE MOTOR IS ALREADY KNOCKING, you're wasting your time installing bearings with the motor still in the car. The times I have replaced them were because I had the pan off for other work, just for peace of mind.

However... a spun rod bearing doesn't mean the entire motor is junk. The 360 in the '73 Fury only had 22,000 original miles, and the bearing spun because it had been dry-started after sitting for 20+ years. It wasn't difficult to inspect the engine (once it was out of the car) and see which rod was loose/out of round. The bad rod was taken to a machine shop and resized, then new rod and main bearings were installed along with a moderate cam, headers, and intake and a Holley carb. That same 360 now runs great in my buddy's '69 Coronet, and goes mid 13's in the 1/4 mile.
 
LOL,I've done 3 cars and a truck this way.The truck and two cars I replaced the rings new oil pimp and they are all still running after many years.As for the oilyness use drip bowls,it will take a few butter contains work really good for this and I used cardbaord to lay on.If you have a couple days to let the oil drip off it helps.
 
butterball said:
I've replaced them successfully twice (as described in my previous post), but I also did a 360 that had a rod knocking in a '73 Fury about 10 years ago, in an attempt to limp the car home. It was quiet for about 70-80 miles, then it spun the bearing again.

IF THE MOTOR IS ALREADY KNOCKING, you're wasting your time installing bearings with the motor still in the car. The times I have replaced them were because I had the pan off for other work, just for peace of mind.

However... a spun rod bearing doesn't mean the entire motor is junk. The 360 in the '73 Fury only had 22,000 original miles, and the bearing spun because it had been dry-started after sitting for 20+ years. It wasn't difficult to inspect the engine (once it was out of the car) and see which rod was loose/out of round. The bad rod was taken to a machine shop and resized, then new rod and main bearings were installed along with a moderate cam, headers, and intake and a Holley carb. That same 360 now runs great in my buddy's '69 Coronet, and goes mid 13's in the 1/4 mile.
Click to expand...
I'll add if it has a little peck at start up usaully inserts will cure it but as you said if its knocking most of the time you need a major overhaul
 
Even with the engine on a stand it isn't easy to the keep the rod ends and bolts from scaring the crank journals. Good luck
 
toolmanmike said:
I do agree with 67 Dart but in car overhauls have been done forever with good results. I had low oil pressure on my 6.5 diesel in my tool truck and I had new bearings slid in and a new oil pump installed. That was 75,000 miles ago. Still no problems. oops, bad luck....I hope it doesn't blow up tomorrow! LOL
Click to expand...

I cant believe you did that. lol
 
Well I think I'm going to try this and if it doesn't work I really aint losing anything. I heard the engine run the other night and if the guy didn't tell me I wouldn't have even noticed that the bearings were bad. Theres no way it's spun because I know what that sounds like. And when I'm down there should probably replace the oil pump too huh?

I'm more familiar with chevy motors because they are what I've rebuilt in the past. And have put high volume pumps in them. But is it a good idea to put a high vol. pump in a 360? I've also always used fel-pro gaskets in my chevy's but is there anything better that you guys recommend?
 
Fel-pros are fine.
I would just use a stock high quality oil pump.
There have been some issues with some brands of oil pumps so do a search on here.
Also check the slack in the timing chain while you have it apart.
 
Yep high vol pump and stock oil pan arent a good combo,as the pump can suck the pan dry. You need to at least baffle the stock pan for a hi volume pump and better if there is increased capacity in the pan.

Really good idea on the timing chain as well. 360 tc is a long one.

Cover the rod bolt ends with some vacuum hose for a little protection against nicks etc while you work the bearings in place.
 
Back when I had my 68 Dodge Coronett with a 383 in it I spun a bearing and since I was in the process of re-building a 440 I decided to replace this bearing with the engine in the car in hopes that it would last me thru the summer or until I finished up the 440. The journal on the crank for this rod felt a little ruff to me so I took a fine piece emory and cleaned up this journal, installed the new bearings and this lasted me until I had finished up my 440 and when I pulled the motor it was still purring like a kitten, so yes it can be done.
 
Slide some rubber vacuum lines on the studs so you don't scratch up the crank. Then go for it!
 
needsaresto said:
Yep high vol pump and stock oil pan arent a good combo,as the pump can suck the pan dry. You need to at least baffle the stock pan for a hi volume pump and better if there is increased capacity in the pan.

Really good idea on the timing chain as well. 360 tc is a long one.

Cover the rod bolt ends with some vacuum hose for a little protection against nicks etc while you work the bearings in place.
Click to expand...

This x1000!

You must watch the oil level with a stock oil pan and hv pump. All my LA engines hold excellent oil pressure with a stock pump. I can't see the need for a hv pump unless you have a fairly hot engine that you beat the he// out of (while of course using a deep sump pan)...
 
I think a high volume is a good idea when there have been oiling mods and the rpm range will be extreme.

I'll be using one on my 451 but it will have at least a 7 qt pan,windage tray and baffles.
 
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