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replace liner (resleve)

I have a sleve for my m70a which i got from advanced in mentor OH. the question was not can tohatsu suply this part. the reason i did not ask this question is because tohatsu can not suply any powerhead parts. any constructive help please.:eek:
 
You heat it up, you press it out, press the old/new one in and then wait somewhere between five and ten hours of operation for it to seize up since the likelihood of getting the sleeve properly placed is very small. The engine is not designed for field sleeve replacements and requires a jig, just the right amount of heat and a great deal of luck. I wouldn't attempt it and I know what I'm doing...The engine has a top value of less than $300.00 in working condition so it's not worth the effort. However, as spare parts it's worth anywhere from a grand to $1500.00. You would be a lot better off to scrap it and sell of the pieces on ebay. There is always someone looking for a working lower unit for one of those.
 
thanks very much guru for your very constructive reply
I will still go ahead with my restoration but if it does not work too well after the rebuild, I will take onboard what you have said about scraping.
One more thing would it be a good idea to cool the sleeve (while the block is still hot) to shrink it before pressing. If this is lame tell me, I can take it.
 
Cooling the liner while inserting(tin can packed with ice) is a method I have seen used, but I don't think it makes much difference unless you are having an issue with the replacement liner going in. IE: Taking too long to insert the liner.

The tin can method works like this:

Find a can of whatever( if I remember correctly Progresso Soup fits it) that fits relatively tight inside the the new liner. Freeze the can with whatever inside it being careful that it doesn't over expand too much. Something with less liquid like beans rather than broth. Now test insert the frozen can into the the liner and see if it still can fit. If it does, heat the block, drop the can into the liner, insert the liner, line it up, press your heart out, remove the now warm can and count your blessings.

Remind me to give you the recipe for "Soup Nagasaki" one day:)
 
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You are a star guru thanks the informative and entertaining answer. My wife wife does not like th idea of having my block in the kitchen for making tinned soup, Some people have no sense of adventure.:)
 
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Or, if available, a small cooler with dry ice will shrink the liner a bunch. We do that on "antique" domestic water (fire) pumps that have a 3-inch bore piston (using leathers instead of rings for piston sealing) with 4-inch stroke.

Procedure: Sleeve set in the frozen Co2... rosebud torch on the (cast iron) block to warm it... then no pressing needed -- just guide the sleeve into place with appropriate tools (too cold to hold in your hands), and in seconds (as the temperatures transfer), bingo -- new sleeve. But those pumps are super-sloppy geometry compared to an outboard.
 
Great reply pvanv. I can't get dry ice here in Scotland but I can get a Co2 fire extiguisher. mmm now let me think about that one.
ok
1 strip the block of all heat sensitive components.
2 mark the liner and the block (so that you can get the new liner in the correct position).
3 heat the block in an oven to 400 deg (ballpark figure) for two hours (also ballpark)
4 press out the old liner with a previously prepared press. If it will not move get a machine shop to bore it out.(you will have to transfer your lineup marks from old to new liner while it is still in the block)
5 if it came out of the block give yourself a pat on the back well done now transfer the linup marks to the new liner.
6 back in the oven with the block as above
7 put liner in coolbox with dry ice if you can get it, Or cover top with insulation with a hole in it to accept the biggest Co2 fire extinguisher you can beg steal or borrow, now the fun part let the whole extinguisher go in the cool box (dont touch the hose you will give yourself a cold burn and also don't do this in an enclosed space or you will keel over and die)
8 take block out of the oven take liner out of the coolbox, drop liner into block, line up marks, have a beer (if it does not drop in have your press ready just in case).
9 next day make shure the top of liner is level with top of block (machine shop if its not).
10 thank guru and pvanv
11 get on the water
If any part of this needs edited feel free to do so, I am not a mechanic or a writer so go for it____
 
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