Sleeve & Rings Only? Which Rings??

[Intermediate Mariner]

I am working on a '62 40hp evinrude. I finally got compression up to a strong 90 on the top and a weak 30 on the bottom... bottom cylinder wall is gouged almost all the way around!

I am thinking leave the top alone since it's smooth with great compression.

Can I resleeve bottom cylinder and just replace rings? And which rings???
(trying to avoid boring both cylinders and having to replace both pistons)

I have a parts manual for my motor and the original part number for the (3) rings is 378430/0378430. The closest I can find is 380108/0380108... I cannot find a ref to a replacement part number.

I have been comparing BRP's parts catalogs from a '68 to my 62' and nearly every number is the same but not the rings (or the block either... the original block is 378647 and new block number is 380253.

Any tips greatly appreciated, thanks a million!

Shawn T
Wichita, KS

 

[wilde1j]

Re: Sleeve & Rings Only? Which Rings??

Bore the bad hole (use a marine outboard machine shop) and replace the piston and ring set to the oversize the hole is bored to. Not necessary to do the other hole, but if it were mine I'd do both.

Resleaving is only done when the block can't be bored and is more costly than boring. Neither are DYI jobs, unless you own a good machine shop.

 

[Intermediate Mariner]

Re: Sleeve & Rings Only? Which Rings??

Thanks for the tip.. much appreciated. Sorry I thought re-sleeve was the first course of action... I didn't know you could bore only one side. And you are right about both sides, just didn't want to buy 2 pistons, 2 ring sets and possibly bearing sets as well.

Can I use the os pistons and os rings from the '68 in my '62 even though part numbers are different?

Thanks

 

[wilde1j]

Re: Sleeve & Rings Only? Which Rings??

Don't know about the interchange.

 

[wilde1j]

Re: Sleeve & Rings Only? Which Rings??

The piston and rings need to be the correct oversize. You will probably have to buy new anyway, since it's not likely you'll have the right combination.

Also, you need to accurately determine the cause of failure, or it will surely happen again. The bad cylinder isn't a cause, it's just the damage.

 

[1946Zephyr]

Re: Sleeve & Rings Only? Which Rings??

Why not just use the block and pistons from your 68? It will work. I once mounted a 68 40hp powerhead on a 59 35hp motor. Worked good.

 

[Intermediate Mariner]

Re: Sleeve & Rings Only? Which Rings??

Good Point Jim, thanks.
What do you think cause could be? I would have figured crud built-up in some passage or another and one cyl got hot. I have everything all cleaned, used combination CLR and Aluminum Jelly. Any ideas?

 

[Intermediate Mariner]

Re: Sleeve & Rings Only? Which Rings??

Thanks Zephyr, I wish! I was just saying that BRP's parts catalogs go back to 1968 and I am finding no referecne anywhere on actual 1962 part number.

 

[cedarjunki]

Re: Sleeve & Rings Only? Which Rings??

Bore the bad hole (use a marine outboard machine shop) and replace the piston and ring set to the oversize the hole is bored to. Not necessary to do the other hole, but if it were mine I'd do both.

Resleaving is only done when the block can't be bored and is more costly than boring. Neither are DYI jobs, unless you own a good machine shop.

not necessary to equalize the cylinders???? bore one but not the other??

that should run great!

 

[wilde1j]

Re: Sleeve & Rings Only? Which Rings??

not necessary to equalize the cylinders???? bore one but not the other??

that should run great!

It's accepted practice to not always bore all. Perfectly fine to just do the bad hole(s). However, any that are unbored must be within service limits AND round, which often is not the case. No effect at all on how the motor runs ... NONE.

As to the cause of damage, possibly overheat (examine the head, gasket, etc very carefully), but more likely dirty carb caused lean condition in failed cylinder. Lean can also be caused by other conditions such as air leaks into crankcase along parting line, a bad crankshaft seal, casting fault, etc. There are other possible causes, but yours is most likely lean running. I would clean and rebuild both carbs.
See here:
http://forums.iboats.com/showthread.php?t=244013

 

[cedarjunki]

Re: Sleeve & Rings Only? Which Rings??

It's accepted practice to not always bore all. Perfectly fine to just do the bad hole(s). No effect at all on how the motor runs ... NONE.
QUOTE]

ok im sorry....
even in school way back when, we were taught to keep the engine balanced.
after reading, the old johnson/evinrudes and most 2 strokes as far as i see were never balanced in the first place.
so that makes sense.

but even so, if it were me i would still do both and keep them equal.

wouldnt having different size bores atleast have an effect of a rougher idle?

not argueing just curious now..

 

[wilde1j]

Re: Sleeve & Rings Only? Which Rings??

Zero, zed, nada ...

 

[1946Zephyr]

Re: Sleeve & Rings Only? Which Rings??

Thanks Zephyr, I wish! I was just saying that BRP's parts catalogs go back to 1968 and I am finding no referecne anywhere on actual 1962 part number.

Oh, okay, gotcha. Well, another option would be to just buy a good used block that is rebuildable and pistons to go with it. You could try any of these places and they may very likely have a good rebuilder on the shelf.

sea-way.com
outboard-parts.com
laingsoutboards.com
tcoutboard.com
fairwindsmarina.com
salvagemarine.com
marinepartsoutlet.com
outboardexchange.com
Superior Marine (800-338-9281)
budgetboats.net
americanoutboard.com
piratemarinesalvage.com
trixieslanding.com
mmmarinesalvage.com
tcoutboards.com

 

[wilde1j]

Re: Sleeve & Rings Only? Which Rings??

Oh, okay, gotcha. Well, another option would be to just buy a good used block that is rebuildable and pistons to go with it. You could try any of these places and they may very likely have a good rebuilder on the shelf.

I can't see how that would be an improvement over what he has, which also needs rebuilding. Not likely to find a motor of his vintage that wouldn't need pistons and rings, or it wouldn't have been junked.

 

[1946Zephyr]

Re: Sleeve & Rings Only? Which Rings??

Well, salvage yards don't care whether they are good runners or not. They'll part them out reguardless. I've hardly seen a 40hp powerhead that had groved cylinders like the one here. Getting a block with good cylinders is easy enough and that would save money on paying for a rebore, plus good used pistons are easily obtainable. Still, a guy can get a good running powerhead for around 100 bucks if they say.....maybe post a want ad here or at the AOMCIA website? Gotta explore the options here. There are ways to get the motor going and not have to pay an arm and a leg

 

[Intermediate Mariner]

Re: Sleeve & Rings Only? Which Rings??

I can have one hole bored for $50 and buy an OS piston for $100 and rings for both side for $90 (but I seen them on ebay for 25!!!). What I would LIKE to do is find a good block and do just rings. Anyone know if a 1960 35hp sea king is the same size block as a 1962 40 hp evinrude??

I seen a couple blocks on ebay for around $50 but they are for '68 and my part numbers for my '62 are different for '68 (pistons, rings and block only thus far, everything else matches).

You mentioned Sea-Way, they have been good in the past on fulfilling parts orders quick and instock.

Shawn