Pulled spark plug wires

[brian3127]

Re: Pulled spark plug wires

I was thinking. If water is getting into the cylinder head won't that turn the gas and oil into foam. I didn't see that

 

[OptsyEagle]

Re: Pulled spark plug wires

Is it a big job to change the head gasket

Not difficult at all. You will need a torque wrench and of course a new head gasket. The head gasket is BRP part number 0307069 or Sierra 18-2957. It's only about $20. The torque is 14 to 16 ft/lbs. I would do 5 ft/lbs all around in the sequence below, then 10 ft/lbs, then 15 ft/lbs.

Before I would order a head gasket, however, I would remove the 10 head bolts and take a close look in the bottom cylinder. It is also possible that you have a crack in the block or something like that. If that is the case, the motor is pretty much a boat anchor, in my opinion, but let us know and we can help you evaluate it. Of course, look closely at the old head gasket as well. It is peculiar, but not impossible, that you would have a blown head gasket and still have reasonably good compression readings, although if I recall your bottom was a little lower then the top reading. I have seen it before and I am hoping that it is the case here as well. Replacing a head gasket on an outboard is easier then pulling the flywheel, in my opinion.

If you are going to tackle the problem in the morning or some other time, give each bolt a reasonable tap with a mallot and punch of some sort, tonight, to try to break any corrosion on them and if you have any penetrating oil, give each bolt a shot of that as well. Give it time to penetrate. Sometimes the bolts can get corroded if the last guy didn't use any anti-sieze on them (which you should do when you put it back together).

Good luck. It does look like water is getting in that bottom cylinder and your motor has all the symptoms.

Note: The diagram below should be used for sequence only. The torque values are not necessarily for your motor.

 

[OptsyEagle]

Re: Pulled spark plug wires

I was thinking. If water is getting into the cylinder head won't that turn the gas and oil into foam. I didn't see that

Gas and oil is always mixing with the cooling water in the exhaust cavity, so I doubt a little more would be noticeable to you. Whatever goes into the combustion chamber would be shot out the exhaust by the piston pressures. The blue smoke from your motor might have been a little whiter. Anyway, that plug is looking pretty clean. You are definitely dropping a cylinder so you could do the external spark test to confirm it is firing. If so, the only other thing it can be is compression and seals. Seals encompass, crankcase seals and head gaskets and of course the block itself.

 

[OptsyEagle]

Re: Pulled spark plug wires

One more thing. When a head gasket is replaced, it is usually a good idea to attempt to re-surface the cylinder head. Overtime they tend to warp a little. If you can, get some 150 grit emory cloth. Place the emory cloth over a very flat surface (a piece of glass is best but anything very flat will work) and in a figure 8 pattern, simply sand down the cylinder head until the entire surface is smooth. When the entire surface is smooth you know it is also flat. It is possible that the warping of the head may be contributing to the water intrusion into your cylinders and better flatness will always make for a better seal.

 

[brian3127]

Re: Pulled spark plug wires

That would be something to do on dry land right my boat is at a slip. Well it would probably be easier on land. I think I will try it at the dock it doesn't look to hard

Yes and the smoke is coming out white

 

[brian3127]

Re: Pulled spark plug wires

I took the head off my motor today and here are the picture of the parts the pictures with the head is where the top is the top cylinder and the pic with the cracked threads for the spark plug is the bottom cylinder

 

[brian3127]

Re: Pulled spark plug wires



first pic is the crack threads bottom cylinder
second pic it the bottom cylinder
third pic is the combustion chamber left side is the top cylinder
fourth pic is the cover of the head it has a bunch of white deposits on it what is that
I had more pics but they wouldn't upload for some reason maybe to big

 

[OptsyEagle]

Re: Pulled spark plug wires

It's tough to say. I don't like the look of the cracked threads but it must be sealing or you would not have the compression numbers you were getting. That being said, if it was not sealing you would certainly be having the kind of problem you were having with that cylinder. Perhaps it unseals when it warms up and seals when it is cold (I think your compression test was done when the motor was cold. If I recall it started acting up again at WOT).

I priced a new cylinder head at $125.00 for your motor. That would be the best fix but now we are talking about real money and you may still have a water intrusion problem. If a cylinder failed due to a lack of compression caused by an unsealed combustion chamber, I would think the spark plug would come out all wet and oily from the fuel that did not ignite. Yours was very clean. I cannot see directly from the head gasket where a leak might come from but that does not say it is not coming from the gasket.

I also wonder where those little pieces from the threads are. Probably shot out the exhaust but if they got into the rings and pistons you might have some good scars on the walls. Did the cylinder walls look OK. Also, does the top of the piston of the top cylinder have that line across it like in your 2nd pic above. I don't recall seeing a piston like that. Is it cracked?

 

[brian3127]

Re: Pulled spark plug wires

The cylinder walls look smoothe
The pistons looked good too other than one is dirtier than the other one
What is this white powder

 

[OptsyEagle]

Re: Pulled spark plug wires

I don't know what the white powder is, maybe someone else has seen it before.

I should also point out that the sealing ability of a compression tester is a little different then the sealing ability of a spark plug, so perhaps your compression reading from the tester is not accurately giving you the compression of that cylinder. Did you notice any oily crud forming outside the bottom spark plug or in the bottom pan of the motor. I am thinking of crap being shot out the threads of that bottom spark plug, when the motor is running.

 

[fishfeatures]

Re: Pulled spark plug wires

Here are my findings warmed the motor up then pulled spark plug #1 the motor spit and sputtered. Then I pulled 2 it ran like nothing happened. Then I reversed the coils and did the same to both cylinders. It stayed the same. Spit and sputtered on 1 and ran like nothing happened on 2.

Right to me, your issue always was no. 2 ... and now it's the one with the damaged plug hole.... i have to think that despite your compression checks that the cylinder head damage is your culprit..without seeing it first hand i can't assume anything other than that, maybe only of the OMC guru's can chime in and help more.If it was me I try and get a replacement head and use that one as a doorstop..

Also the white residue may be salt deposits (do you boat in salt water?) from water leak somewhere on the head, check the thermostat housing out for that cause the head gasket seems intact.

 

[brian3127]

Re: Pulled spark plug wires

Fresh water I bought it 8 years ago so I don't know after that
It's is the underside of the head gasket looks like a crack maybe

 

[brian3127]

Re: Pulled spark plug wires


The left Sid of the picture is the bottom cylinder it looks pitted

 

[fishfeatures]

Re: Pulled spark plug wires

change the head gasket anyway, it's a cheap fix if it is that. The slight dings in the head are more than likely the damage caused by the broken part from the plug hole, just double check to make sure the cylinder walls aren't scratched at all....

 

[OptsyEagle]

Re: Pulled spark plug wires

Fresh water I bought it 8 years ago so I don't know after that View attachment 197690
It's is the underside of the head gasket looks like a crack maybe

It's tough to say, but it does look like water could get through there. It certainly looks like combustion certainly tried to so I can't imagine why water wouldn't. The bottom cylinder certainly looks a lot cleaner then the top and that is usually a symptom of water intrusion.

This is a tough one. You could throw another $20 at a new head gasket. Re-surface the head you have and then torque down the new gasket. It might just work just fine.

 

[brian3127]

Re: Pulled spark plug wires

I don't know what the white powder is, maybe someone else has seen it before.

I should also point out that the sealing ability of a compression tester is a little different then the sealing ability of a spark plug, so perhaps your compression reading from the tester is not accurately giving you the compression of that cylinder. Did you notice any oily crud forming outside the bottom spark plug or in the bottom pan of the motor. I am thinking of crap being shot out the threads of that bottom spark plug, when the motor is running.

There is what looks to be oily substance on the pan of the motor

 

[OptsyEagle]

Re: Pulled spark plug wires

I use to have a 9.9Hp that had a spark plug hole (bottom) helicoiled. I guess someone who owned it before me stripped it. In any event, overtime that helicoil started to unwind. It slowly started preventing me from getting a good seal with the plug (part of the helicoil was protruding out where the plug seal needed to be). The motor still worked but that cylinder was a little weak (struggled hard to keep the motor running alone). I also remember that the pan of the motor was always dirty with oily crud. I could have re-helicoiled it but I eventually acquired a new cylinder head and the bottom pan of my motor now is always very clean.

I wish I could advise you better, but the best fix would be a new cylinder head with a brand new head gasket. You could search Ebay and see if you can find a used one or even some used outboard parts suppliers (search the site here for names) and see if you can get one a little cheaper.

 

[brian3127]

Re: Pulled spark plug wires

I'm going to try and get this head fixed. I have a lot of people at work that work on small engines I'm going to see what they say about it.

I just want to thank you Optsyeagle for all your help and everybody else too.

I will let you know what happens.

 

[brian3127]

Re: Pulled spark plug wires

just a quick update i talked to guy at work about the cylinder head and he said just try resurfaceing the head and put new gaskets on and try it. If it doesnt work then go buy a new or used head for it. and that it wouldnt hurt to try that first so thats what im going to do. Trying to do it cheap. i got the head resurfaced for free here at work so im not out any money just ordered the gaskets they should be here tomorrow.

 

[brian3127]

Re: Pulled spark plug wires

i got the gaskets yesterday. going to put the motor back together after work should i put something like oil in the cylinder before i put it back together. i had to wipe the cylinders out because white powdery stuff fell in to the motor from that water jacket gasket when i was taking it apart.