Piston looks chipped - 1995 88 SPL

[Caseyuconn]

I am in the process of changing my outer exhaust cover gasket because I noticed a small amount of water leaking.

After removing the outer exhaust cover and looking in I notice one the upper starboard piston looks chipped on the edge. See picture attached. Note compression is all withing 15 psi.

1. How bad is this, does it need attention immediate attention? Or can it be run this season without fixing this?
2. Is it possible to replace this piston without completely disassembling the motor? Is it possible to disconnect the piston from the exhaust port?
3. How much are we talking for a shop fix of this issue?

Thanks

 

[Daviet]

Re: Piston looks chipped - 1995 88 SPL

1. Can't really tell by the pictures, probably my computer.
2. To replace a piston, you will have to remove the power head and disassemble it.
3. Depends on shop labor rate, if bolts are broken upon disassembly and probably other factors. Should probably call around your area and ask for some estimates.

 

[wilde1j]

Re: Piston looks chipped - 1995 88 SPL

I can't tell either. Powerhead must be removed and completely torn down to replace a piston, rings, etc. Probably 12 to 15 hours labor, plus machine shop costs and parts. Somewhere around 2000 to $2500 all up order of magnitude, unless there's more internal damage and/or saltwater motor.

What were the compression readings. That should give a clue as to whether a rebuild is needed right now or soon or not at all.

 

[Randy J]

Re: Piston looks chipped - 1995 88 SPL

whew what he be burning for fuel #7 boiler oil ? Daviet isnt yur puter i had to really look hard to figure out what i was a looking at ?? i assume 3rd pic far left cylinder wall?

 

[boobie]

Re: Piston looks chipped - 1995 88 SPL

Run it till it blows and then it will really get expensive or repair it now while you still have a chance.

 

[Caseyuconn]

Re: Piston looks chipped - 1995 88 SPL

The compression was like 125s and a 110.
I just bought the boat and motor.. so I can either take it to the shop and have it repaired.
Or run it this season save up for a new motor when she goes. It seems like the edge of the piston is chipped and rounded.
The rest of the pistons look ok from what I can see, however they aren't all visible in the current position.

 

[Mas]

Re: Piston looks chipped - 1995 88 SPL

I can't quite make out the "chips," but if you see them...not good! No, you cannot disconnect the piston through the exhaust port. Was the 100psi on the piston with the chips? Broken ring??

I personally would not run it until it blows. If you're gonna buy a new one, sell the existing to someone who can make their own repairs before you wreck the motor. But if you do sell, make sure you disclose the "chip issue," be honest!! If you are not honest, bad boating karma will catch up with you.

Mas

 

[levi_tsk]

Re: Piston looks chipped - 1995 88 SPL

you guys that looks like carbon build up on the top of the rings to me JMHO run a shock treatment of seafoam through it and reinspect -that thing is grubby in there and youll be able to tell more once you shock it as itll be ALOT cleaner

 

[levi_tsk]

Re: Piston looks chipped - 1995 88 SPL

whew what he be burning for fuel #7 boiler oil ? Daviet isnt yur puter i had to really look hard to figure out what i was a looking at ?? i assume 3rd pic far left cylinder wall?

i was wondering the same thing...

 

[Caseyuconn]

Re: Piston looks chipped - 1995 88 SPL

I'll post better pictures tonight. Note that you are looking through the exhaust port so all that black junk is carbon and exhaust build up.
The previous 3 pictures are looking through the upper right of this cover when removed.

 

[Big flop]

Re: Piston looks chipped - 1995 88 SPL

Try light scraping with a small flat blade
screwdriver and see if it chips off.

 

[Mas]

Re: Piston looks chipped - 1995 88 SPL

Is this a saltwater motor?

 

[Caseyuconn]

Re: Piston looks chipped - 1995 88 SPL

The previous owner did have in saltwater (Delaware) and I will have it in saltwater (long island sound).

 

[emdsapmgr]

Re: Piston looks chipped - 1995 88 SPL

A chip at the top of the piston will eventually lead to a problem. Any chip will permit the heated exhaust gas to travel downward to the ringsets. Over time, it will promote carbon accumlation and the heat willl stress the rings. Likely will result in a ring failure at some point in the future. When this happens, likely the piston and head will take the brunt of the damage. Once that happens, it's also possible that the cylinder liner will get some grooves in it, which may require boring. I'd be more concerned as to why the piston chipped in the first place..did a ring already let go? Is the head over that piston already damaged? Your compression numbers indicate that there is already some condemning damage. You need to take the head off for a visual inspection.

 

[Caseyuconn]

Re: Piston looks chipped - 1995 88 SPL

Here are some additional pictures.

Upon closer inspection it appears the top ring is completely gone.
I'm fairly sick over it considering I literally just bought the boat and Im really on the fence about whether to get it fixed or not.
It appears to run ok. I has decent compression. And if I sink $3000 into a 1995 to fix this there is no guarantee it won't blow next year.
I would like to advance the piston to check on the other ring and the other pistons, is there a way to do this by hand without screwing anything up?
Thanks

 

[Mas]

Re: Piston looks chipped - 1995 88 SPL

Remove all the spark plugs and manually turn the flywheel to view other parts of the piston from the exhaust ports. You will not be able to see but a little of the piston & rings. Clearly, your last set of pictures have shown me enough.

Do not run the motor...I'll only make it worse. I would remove the head to see if any cylinder damage is present...beware of broken head bolts being that the motor was in salt water. If you break a headbolt, your problems will be worse.

Mas

 

[Caseyuconn]

Re: Piston looks chipped - 1995 88 SPL

Now that I am thoroughly depressed I am going to start calling around for estimates.
I think a safe estimate would include a .030 over bore and 4 new pistons. Keep the same rods and other usable parts.

Does anyone have any experience with the cost of this work? Im look for a rough estimate to have a baseline going into my dealings with the marine shop.
Thanks

 

[wilde1j]

Re: Piston looks chipped - 1995 88 SPL

Why not look on iboats for a rebuilt PH? Very easy.

 

[BKS72]

Re: Piston looks chipped - 1995 88 SPL

I just finished rebuilding a 95 crossflow V4. Bore and hone on all 4 cylinders was around $180 and the rebuild kit (pistons, rings, rod bearings, rod bolts, thermostats, and gasket set) was right at $650. You'll be almost a grand into it just in parts and machine work and by the time you pay shop rates of $90 an hour you'll have another grand and probably more in it. Depending on how bad it is you might save some money on parts but a busted off bolt or two and the additional labor would eat that up quick.

If the other three cylinders are OK and you just need to clean up the one and replace 1 piston/ring set you could get out cheaper.

If I didn't do my own work I would either look at a rebuilt powerhead from here or a good used local powerhead or motor. You'll have about the same amount in repairs as you would in a replacement.

Just my $.02.

 

[yoster]

Re: Piston looks chipped - 1995 88 SPL

I'd wager you can probably find a good used outboard cheap.. even if a guy is selling it with the boat. Look for craigslist posts where they say the engine 'needs engine work' and ask them for the engine symptoms. What you're looking for is an engine that sounds like it might have carb issues.. something you can EASILY do yourself... but at the same time can play the doom and gloom story to the owner to get it real cheap.

A few people around here do just that; buy these 'bad' motors off the non technically inclined owners, fix them for under 100 bucks, then re-sell for a few grand.