you can loosen all the mains and slide them out and in one at a time .I wouldnt expect good results though. That type of "repair" is a used car lot type of patch job and rarely gives a real satisfactory result.you will just be opening a can of worms. JMHO
As cheap as they are why not rebuild it ?

 

If you have a bad bearing, chances are the crank is marred somehow and needs work......

 

If you have a bad bearing, chances are the crank is marred somehow and needs work......

It's my fault the bearing is damaged. (please don't ask :sweat: ain: )

Really only the bottom part of the main bear needs to be replaced...but I guess there will still be a small difference even if i get the same size...This sucks I don't know what to do. ain:

Latech, do you mind explaining to me why its bad to do it like that?
And I can't rebuild it... I just can't lol everything I've tried to rebuild ended up getting detroyed.
l

 

It's my fault the bearing is damaged. (please don't ask :sweat: ain: )

Really only the bottom part of the main bear needs to be replaced...but I guess there will still be a small difference even if i get the same size...This sucks I don't know what to do. ain:

Latech, do you mind explaining to me why its bad to do it like that?
And I can't rebuild it... I just can't lol everything I've tried to rebuild ended up getting detroyed.
l

I don't see any reason why you can't replace just the damaged bearing shell. Just do it. There should not be any difference as long as all the bearings are the same. For example : standard, .010 or .020 undersize. Not a problem.. Allan .....P.S. I have rolled in several sets of main bearings over the years with no problems .

 

I too have done this many times in the past - and it wasn't a used car lot job any of the times but a standard garage repair on daily drivers.

 

It's my fault the bearing is damaged. (please don't ask :sweat: ain: )

Really only the bottom part of the main bear needs to be replaced...but I guess there will still be a small difference even if i get the same size...This sucks I don't know what to do. ain:

Latech, do you mind explaining to me why its bad to do it like that?
And I can't rebuild it... I just can't lol everything I've tried to rebuild ended up getting detroyed.
l

Well you can just put the one in if you just replaced a set and damaged one.
The car lot repair is just that.
I have seen it done many times. I wouldnt start a long trip in a car with that type of repair done.
If you have wear on one bearing and the rest are decent then there is an underlying problem.If the problem is oil starvation, tightening up the clearance with a new bearing will make it worse.
In your case just slide a bearing in and hope for the best.you have nothing to lose.
I have replaced bearings like you are talking about , usually works but there is almost allways some issue that takes away from it being a satisfactory repair.Most of the time it will have a noise like a knock.
Like a rusty tow chain that you weld a broken link, and when you go out to use it , it breaks again at the next weak link, a patch job is a patch job.
Not something I would start off across the country in.

 

I too have done this many times in the past - and it wasn't a used car lot job any of the times but a standard garage repair on daily drivers.

Last shop that I worked in , in '84 and '85 I did several Ford 351M and 400M engines . Even had to shim a couple of them between the main cap and the bottom bearing half to tighten them up when the customer couldn't afford a crank replacement. Why we didn't just go with .002 undersize bearings . I guess you'd have to have asked the shop owner . But we really didn't know how loose we were until I had rolled in the new bearings and plastigaged . Couldn't take the bearings back out and repackage them and sell them to a walk-in customer after having installed them, I'm sure. Nevertheless , I did several and never had a failure .

 

I too have done this many times in the past - and it wasn't a used car lot job any of the times but a standard garage repair on daily drivers.

I agree it can and has been done. I worked at a shop that did a repair on my landlords truck. Did exactly what is being discussed here. I told him privatley to put in a new engine(a fuel leak from the injector fuel line on a 4.3 leaked inside and washed out the bearings.)
The shop owner talked him into sliding in some bearings and a pump.
A month or so later he had decided to sell the truck. Seems he could hear the little knock that was still in the engine and was somewhat concerned.
He said he wished he would have listened to what advice I gave him a month or so before.
He sold the truck and bought a nicer newer one with a bad engine, and had me put it in. I put the engine in at the NEW SHOP i work at. :thumbup:

 

If you have wear on one bearing and the rest are decent then there is an underlying problem.

the problem with the bearing was I used a hammer to tap it in and dented it. ain: don't make fun of me I learned......

Would it still be a patch job then if I just replace what I messed up?

And also how come by doing this the engine can knock? I'm not doubting you or anything I just don't understand.

Oh and also how do I know what size bearings I have? Only number i see is 3 on the back side.

 

Well you can just put the one in if you just replaced a set and damaged one.
The car lot repair is just that.
I have seen it done many times. I wouldnt start a long trip in a car with that type of repair done.
If you have wear on one bearing and the rest are decent then there is an underlying problem.If the problem is oil starvation, tightening up the clearance with a new bearing will make it worse.
In your case just slide a bearing in and hope for the best.you have nothing to lose.
I have replaced bearings like you are talking about , usually works but there is almost allways some issue that takes away from it being a satisfactory repair.Most of the time it will have a noise like a knock.
Like a rusty tow chain that you weld a broken link, and when you go out to use it , it breaks again at the next weak link, a patch job is a patch job.
Not something I would start off across the country in.

I agree that if there was just one bearing worn and all the rest looked good you may be looking at a warped block that would need line honed or a bent crank that would need straightened and turned. I don't like the sounds of straightening a crank, but there is an engine shop in town that does it.

 

No, you will be OK. just put in another.Like I said, you dony have anything to lose and everything to gain.

 

How do I figure what size bearings I have so I can replace?

 

I dont mean to discredit anyones opinion about rolling in a set of bearings, It is just a repair I dont like and maybe my reservations about it are a little zealous.

 

How do I figure what size bearings I have so I can replace?

They should be labeled on the back.What size did you put in to start with?

 

I agree it can and has been done. I worked at a shop that did a repair on my landlords truck. Did exactly what is being discussed here. I told him privatley to put in a new engine(a fuel leak from the injector fuel line on a 4.3 leaked inside and washed out the bearings.)
The shop owner talked him into sliding in some bearings and a pump.
A month or so later he had decided to sell the truck. Seems he could hear the little knock that was still in the engine and was somewhat concerned.
He said he wished he would have listened to what advice I gave him a month or so before.
He sold the truck and bought a nicer newer one with a bad engine, and had me put it in. I put the engine in at the NEW SHOP i work at. :thumbup:

I'd say that after the fuel dilution there was a good chance of wrist pin slop and piston skirt wear.

 

I don't know original size, bought it from a dude.

ooh I found some letters.

STD. That's standard I'm guessing?

 

How do I figure what size bearings I have so I can replace?

Turn the bearing over so you can see the back side. The size will be stamped into the shell, most likely. Just replace the damaged half.

Don't worry a bit about any size difference between one set of undersize bearings compared to another set of undersized bearings, as long as their undersizes are the same (0.010", 0.020". etc.). Bearing halves are used on purpose that are 0.0005" different (as an example) to fine tune clearances.

 

I'd say that after the fuel dilution there was a good chance of wrist pin slop and piston skirt wear.

There were grooves(light) in the journal and the bearing(s) were on the bronze.He only drove it a few miles after is started knocking and it actually hydrolocked at one point from the flood of fuel. ain: just not a good scenario for a great outcome.

 

I dont mean to discredit anyones opinion about rolling in a set of bearings, It is just a repair I dont like and maybe my reservations about it are a little zealous.

I take no offence. Always best to make the best repair possible. Sometimes people can't afford to have the recommended repairs done and you like to give them the option of a cheaper repair with the understanding that it is not the preferred repair and carries no guarantee. Their money, their choice .

 

I don't know original size, bought it from a dude.

ooh I found some letters.

STD. That's standard I'm guessing?

Yebber! ( yes)

 

I take no offence. Always best to make the best repair possible. Sometimes people can't afford to have the recommended repairs done and you like to give them the option of a cheaper repair with the understanding that it is not the preferred repair and carries no guarantee. Their money, their choice .

I Agree. It is a crap shoot. It is allways a good idea to put it on the repair order and have the customer acknowledge by signing it.

 

I don't know original size, bought it from a dude.

ooh I found some letters.

STD. That's standard I'm guessing?

No guess about that . STD is a standard size bearing. Is that what was on the bearing that you took out of the engine to start with ? That is what is important . Nobody on here should criticize you . We all had to start somewhere .

 

No guess about that . STD is a standard size bearing. Is that what was on the bearing that you took out of the engine to start with ? .

yes.

Thanks for all your help guys. :welcome:

I'll let you know what happens when I get it running (If you don't hear from me assume the worst). :smash:

 

Opyder... just roll another bearing in the spot in question. It helps to loosen all the main bolts , only enough that they are loose. dont back them off too far that way the other ones wont shift or drop out and the main you are replacing should slide in pretty easy.

 

Opyder... just roll another bearing in the spot in question. It helps to loosen all the main bolts , only enough that they are loose. dont back them off too far that way the other ones wont shift or drop out and the main you are replacing should slide in pretty easy.

I'll keep that in mind, thanks.