I am rebuilding the engine on my D47U (7500 hours) and I wanted to get some opinions on cylinder liners. It appears that the replacement liners are available from Cat. However, mine are in fairly good shape. Can the liners be bored .030 or .020 over size? Can the liners be honed if they are still within spec. Or is it more cost effective just to replace? It seems like most folks replace them if they have the engine torn that far down. If I was to leave the stock liner should I remove them to replace the copper seals or just leave it? Thanks

My D47U had been sitting for a long time in the open with water coming in the stack. I checked several sources and found aftermarket liner kits at about 1/4 the price of genuine parts. When checking the dealer, the wrist pin was reported to me as NLS. So I bought the aftermarket liner kits and was pleased. Two of the kits had the wrong quantity of rings but the dealer fixed that. I was pleased.
Elton

The liners are to hard to accept rebore but can be honed using hard stones to restore the oil control cross hatching if the bores are within spec. While you have the engine down you should pull the liners,
check the copper seals and the rubber liner seals and also check for corrosion and pitting on the water side.

What was your source for the aftermarket liners?

It has been some discussion on the board about CAT genuine and aftermarket. CAT has been real useful to lots of members and there is a great deal of loyality. I understand that. I have only been a member for a year or so I don't want to insult the membership or CAT, so please call me and I will refer you to my source for aftermarket parts. Daytime work number is 540 389-7296. Elton

Hello Elton, it takes a fair bit to upset members here, so don't be afraid to share your information, most folks I know are trying to save dead Cats on a budget and for many, money is tight, what has surprised me in the past few years has been the big jump in prices for genuine parts, seems many things have doubled, even more, while other bits are not available.

I've had to re-sleeve two D4 engines in the last couple of years here in Australia, they were the earlier D4400, genuine Cat liners for them used to be reasonably priced, like $120 each, so it was a no brainer to use them, even though places Stateside were selling aftermarket for around $60 because shipping international is expensive now.

Those thin copper gaskets that sit under the lip of liner are another trap to watch out for, at the time genuine Cat were around $40 each while aftermarket here were $10 each, the $240 I saved on those copper gaskets for 2 motors was very handy to buy other parts, the rubber O ring seals are another good example.

I try and buy genuine Cat parts when ever possible, however if there are quality aftermarket parts available at a significant price saving, I'm all over them like a rash! LOL
Good luck with your rebuild
Mike

when searching for parts for my Cats on the Cat website (local dealer online parts) I found many times the Cat part and then an aftermarket part that they recommend-(Cat classic) for machines not used every day--some up to 1/3 the price of the Cat part

I got the quote back from Caterpillar and it looks like its about $653 per cylinder for liners pistons and rings. I dont mind paying for quality but i was wondering if anyone had any experience with CTP or any other brands? From what I have seen it seems like I can buy these kits for around $200 per cylinder for a significant savings. Also, does anyone have any experience with decking the block and head on their D315? How did you make up the difference for what was removed? Are thicker head gaskets available? The parts book doesn't not list any. I assume you don't want to change the compression ratio, valve clearance or push rod length. Any help is appreciated.

Hi Team,
from memory there is some come and go with block decking on these old lowish compression engines.
There were some guidelines but they were in the hands of our outside machinists who did this work for the Dealer.

As a rule the absolute minimum was removed ---witness cleanup--and this amount was stamped on the block in a certain place for future reference.

It goes without saying that the top deck length has to be true to the crank center line and square across to the liner bore in the block--if the liner seats and/or the top deck face are not square to the liner bore the bottom of the liner will contact one side or the other of the lower liner bore, which is a clearance fit, and will usually cause the liner flange to break off as the head is tightened or later in service. Same applies when doing counter boring of the liner seats in the block.
The liner counter bore seats were cleaned up and liner shims were selected as is usual to get the standard liner protrusion measurements--see scans below.

Hope this helps.
Cheers,
Eddie B.