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Question : Rebushing wet liner seal surfaces

windsormw

Aluminum
Joined
Dec 11, 2006
Location
The corner of Hill & William
Good morning ,

I have a very old Case 680 ck ( b ) tractor backhoe which these days is rare but until now has always been in good working order .

The cast machined surfaces of the engine block where the wet liner O rings seal too ....has failed . Flaking away in short , I found some RTV sealant was present around liner O rings from the last fellow that had it apart no doubt .

The repair :

Just two options I've found at this point

1. Machine out the uglies , fit a bushing with red lock-tite & machine again to size .

2. Machine out the uglies , apply belzona 1511 ( ht ) & machine to size .

Regardless the repair method my plans are to coat the inside of block with belzona 1391 ( ht ) for long term piece of mind .



Could you please provide your opinions /options to this problem

Best regards
Scott J
 
Generally by the time the "O"-ring seats have gone bad, the liners are also worn and need attention.
Would consider oversized liners . machine damaged sealing surfaces back to fresh and fit liners to match.

Cleaning up seats and fitting sleeves seems a good solution. Not a big fan of "glue" to fix this sort problem.
Seems that no matter how well prepped and applied, the coolant will always find a way to get between the parent material and the coating and corrode ,if you will from the inside out....

Me, if i could not go the new liner route and was to use a repair sleeve, would consider thread milling the sleeve and the block. Makes installing the sleeve easier and you can use a very thin sleeve as no press is required.
Further you can install the sleeve while the block is still on the machine (no real force need to install the sleeves) so no additional setup needed top finish the sleeve bores to accept the liners...
Just map the center locations of all bores,before doing the cutting to accept the repair sleeves, then return to the same position and finish for the liners...
Cheers Ross
 
1. Machine out the uglies , fit a bushing with red lock-tite & machine again to size . ''

Is how my neighbours - a long established engine rebuild firm, over come that problem,(but with green retainer loctite) ………...on iron blocks they use cyl liners to make the sleeves.

To the best of my knowledge they've not had one ''come back''


X2 on what Alfa GTA says - the man knows what he's about - especially his comments on building the accuracy in to the job as you go.
 
There is a place in salem, ohio that will make you custom sleeves for about 100.00 each if you wanted to go that route. It called powerbore cylinder sleeves
 
Ive done quite a few Caterpillar motors with corrosion of the seal surface......Just clean away all rust and rebuild the area with filler devcon or belzona or what you like.Mould the stuff to size before it hardens,or if you have the equipment ,oversize the filler and machine it cylindrical......Usually the top seal ring area is affected ,so there is still plenty of support for the liner lower down.
 
I've done this repair more than once on tractor blocks using just a portable Kwikway boring bar. I bored the bottom diameter for a sleeve that was slightly smaller than the top diameter, so that I could get the repair sleeve past the top. Chamfer the top of the repair sleeve the same as the original block before you install it, then finish bore to size.
 
I like the custom sleeve with a larger od. Seen some repairs last, and others not. Dont like the plastic filler, seen one Detroit come apart after only 1600 miles. In any case, you have to remove metal, just make sure there is enough left to suport the sleeve and not impair the strength of the block. The area between the bores can be thin and prone to cracking, even in unmodified blocks. If the pitting is not to bad, the silicone works pretty well, and less danger of cracking. Just an fyi, I always fill the block with water after the sleves are in, just to make sure they seal before putting the rest together. Good luck with it.
 
Are you doing the work on a hobby basis, or paying to have it done? How long did the silicone from the last repairman last? You are talking about a machine with a value slightly above scrap when in working condition.

Personally, I'd reseal it with silicone and put it back together with an absolute minimum of expenditure.
 
Are you doing the work on a hobby basis, or paying to have it done? How long did the silicone from the last repairman last? You are talking about a machine with a value slightly above scrap when in working condition.

Personally, I'd reseal it with silicone and put it back together with an absolute minimum of expenditure.



Doing the work myself , in frame . Not sure how long the previous silicone lasted , had this tractor for a couple years . I'm talking about a machine in good working order .

The amount of pull required to drag these liners out of the engine block was impressive & I'm not sure I want to go through that kind of wrestling match again in the near future .

The cast material ( iron or steel ) has flaked away considerably upon these seal surfaces which is leading me to a more permanent fix .

A used backhoe in my area will pull 20k & full of someone else's problems , usually sporting an aerosol overhaul and most likely had the stuffing beat out of it . I've come to know this gal , shes worth the effort - parts are scarce ......& I'm allergic to payments.
 
Seems you have the Case A 301 BD engine....fitted to other machines as well,so I would suggest looking for a good block,you might even find a NOS block if you try the tractor spares specialists.
 
"Red Loctite". "Green Loctite". Meaningless terms. There bare 7 red Loctite compounds. There are 5 green. They have numbers y'know.
 
I know its tough, but I would have never thought of it to repair engine block.
Have you actually done or seen a repair done this way and how long did it work?
 
I have rebuilt seal areas of Caterpillar engines with Devcon,and the repair has still been ok at next teardown ......The main consideration is to enable the entry of new liner seals without tearing ,or dislodging them..........once the seals seat in the block,the job is finished ,and it doesnt really matter if the filler dissolves.There are all kinds of different wet liner systems.......some have seal grooves in the block,some in the liner,and some have a single larger seal that seats against a ledge.Damage to seal areas is often by cavitation as well as corrosion,and a correct coolant inhibitor is essential.
 








 
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