Re: Loose Rod
 

I would never shim an insert bearing. Either the crank will need polishing or something is wrong with the bearings.

Re: Loose Rod
 

It sounds like I should polish the crank and maybe make a phone call.

Should have thought twice about the shims. I just want to figure it out and get it done.

Re: Loose Rod
 

Well I learned something new today. In the 50 plus years I've been fooling around with old cars I've never heard about bearing shims like these. Has anyone actually tried them, do they work or are they like sawdust in the crankcase?

Re: Loose Rod
 

They have been used a lot to keep an engine going a bit longer after they got worn out.

Re: Loose Rod
 

If everything else checks but the full bearing clearance to the journal then a shim can be an effective repair,as long as it covers the tang of the bearing it shouldn't give you an issue.But,that isn't the proper fix,who ever cut the block fitted the bearings and crankshaft has some explaining to do if your findings are accurate.

Re: Loose Rod
 

I have used the tapered shims behind the inserts--- I was shown how to use them in school. Was a Datsun 510 that ran with coolant in the oil, inserts all down to copper, crankshaft had some scoring, --- I do know it lasted over50 miles of towing a VWThrough the hills of western New York in second gear---- my 74 Chevrolet truck has them behind the inserts because the used crankshaft I found at the time was worn--- been 40 years since , still running, has more mileage than the original engine went --- at the time I figured it would be good for 50k, got 55k now-- the one used piston rattles some cold now, still holds good oil pressure
There's some fitting needed depending on how much shim you use, some has to be filed off the parting surface of the insert so it doesn't buckle--- file too much and it's too loose and will spit out shim and spin

Re: Loose Rod
 

Years ago we used what we called "check paper" under insert bearings. We went to the bank and got blank cheques and cut them up for shims. Worked good on old tired engines.

Anyone else remember the crankshaft grinding while the engine is still in the car?

Re: Loose Rod
 

Yes I did it when I first started working for my Dad in his repair garage. I still have the grinder. I have used it to grind rod journals on a model A crank in my lathe.

Re: Loose Rod
 

When I was in my teens, I watched my father shim the insert bearings in his very tired Austin. He switched top shells to the bottom and vice versa and used cigarette papers behind the worn ones (the ones with little loading) When more than a single layer was required, he cut the extras at decreasing lengths to get the tapering effect. He cut holes in the papers for oil after that.
We drove he wheels off that car for years but I think I'd use metal shim material which is available from 0.001" thick.

Re: Loose Rod
 

I talked to the shop after I determined that it was the inserts and not the crank journals. Ever ugh once in a while, an insert or two might be off a bit so it happens. He will probably hone a few thousandths off, if that.

Re: Loose Rod
 

Loose rods need building up not honing. What did I miss here?

Re: Loose Rod
 

The loose rod problem was fixed by switching the rods to different journals. The other two fit too tight.

Re: Loose Rod
 

Wow! What are the odds of getting two inserts out of four in a set that are off tolerence? I can't recall working with any and I have used over 180 sets of four from the same manufacturer.
Seems more likely the journal sizes are off spec. Just speculating.
I hope it all works out. Good Day!

Re: Loose Rod
 

Jack Shaft is right on. It seems like someone doesn't know how to use measuring gauges or measure. The crank journals should all be the same dimension within +/-.0003". The rod inserts should all be machined the same and mated to the crank approx. +.0015" according to Jack Shaft. It would seem to me that if the above has been applied you should be able to install a rod in any position blindfolded and have the same results.
Torquing is not the solution. If the crank journals are not all the same have your machinist make them all the same. Then buy new rods that are properly mated to the new crank journal dimension or re-machine the inserted rods you have to properly fit the crank. This would probably involve removing material from the caps and reboring the inserts to the new crank diameter + some clearance (use Jack Shafts spec).

Re: Loose Rod
 

I agree never found a insert off. Honing a insert is a bad idea. There is not that much bearing material on them.

Re: Loose Rod
 

It is not the crankshaft as those two rods are stilll tight on every part of the crankshaft. They might just give me different inserts.

Re: Loose Rod
 

I wonder if these are custom made bearing shells or if they are using some Kubota tractor bearings or what have you. The bearing material is layered with the final layer generally plated onto the surface. To remove any of the layers would not be something I would not even consider. The manufacturer of the bearings needs to get their ducks in a row on their processes. Out of spec journal bearings are bad products and the manufacturer should lick that calf over until there is satisfaction for the end user.

Re: Loose Rod
 

"should lick that calf over until there is satisfaction" :)


Have not heard that one before, had to think about for a few seconds to understand it, but I do like the phrase.

Re: Loose Rod
 

That is the issue with inserts,wear through the thin layer of babbit and then you begin wearing the part it bears.Neither copper or steel backed inserts have forgiveness when the babbit is gone.

Re: Loose Rod
 

Problem solved. It was human error on my part: I accidentally switched the rod caps between the two. Now they fit perfectly. Mistakes happen.