spark plug condition photo

[Vic.S]

Re: spark plug condition photo

I'd be looking for reasons why that cylinder might be running on a weaker fuel/air mix. Air leak around the intake manifold or defective carb perhaps.

An ignition fault would not produce that light deposit .. If anything it would be more oily than the other plugs wouldn't it?

The extra couple of ounces of oil in 9gallons is not a great deal. That engine use premix .. not got an VRO/OMS ?

 

[Dhadley]

Re: spark plug condition photo

The QL77JC4 is an accaptable plug to run in that motor - not an issue.

Is that plug out of #1 cylinder (top starboard side)?

 

[bob johnson]

Re: spark plug condition photo

The QL77JC4 is an accaptable plug to run in that motor - not an issue.

Is that plug out of #1 cylinder (top starboard side)?

the plug came from the port side....I am more than 50 % sure it was the top plug.

my seloc says QL77JC4 for 1995 115 hp 60 degree motors

then it lists QL82YC FOR 1996
then it lists QL78YC FOR 1997-01
I checked in the bores with a light tonight, all the cylinders look similar...dark carbon buildup mostly covering the piston top...thin, and blotchy...

bob

 

[seahorse5]

Re: spark plug condition photo

my motor is a looper 60 degree!! not a 90 degree CV

could a leaking primer bulb right before the motor cause a lean condition if motor was run at a high speed for a, long time?

could really smell gas and discovered the hose clamp could spin easily around the hose

bob

Your motor should use the Champion QL78YC plug gapped at .030" according to the factory plug chart. A QL77JC4 can work but it may foul quicker and the low speed running characteristics are not as good as the extended nose QL78YC plug.

Yep, a leaking primer ball clamp can allow air to get sucked into the fuel system and make the motor not only run lean but pump more oil than needed.

 

[steelespike]

Re: spark plug condition photo

Could the deposits be salt from minor water intrusion??Crumble it and taste.

 

[bob johnson]

Re: spark plug condition photo

Could the deposits be salt from minor water intrusion??Crumble it and taste.

I took the spark plugs to my mechanic....I call him the "old codger"

he is a grumpy, but nice guy..been at it a long long time...

he thinks that water got into my gas, or at least got into the carburetor!!

he suggest that the O -ring that is someplace under the head , might be leaking...

he said it isnt a head gasket....but a place just to seal off a water passage and it uses an O-ring.

will pull the water seperator tonihgt.

i told him I have two portable 9 gallons gas tanks that stay inside closed storage under the front deck.. they only come out to get refilled..

and water fronm waves doesnt splash on them....so...I cant figure how the water is getting in VIA, my gas!

unless it is the gas station

but then that doesnt explain the one really bad spark plug, the one kinda the same but half as bad, and the other bank is fine!!

so it seems to isolate the problem to one head...

I bought 4 new plugs and two new thermostats and housings.

next week I might go for pulling the head to check around and replace all the seals and gaskets..

he says those carbs dont get clogged much,...

thanks

bob

 

[Dhadley]

Re: spark plug condition photo

OK, there are no head gaskets on that motor, only O rings. They rarely leak. If that plug came out of #4 cylinder there was an issue with the first series of 60* V4s leaking water into #4 when the motor was tilted.

However, I don't think we've actually established that it's actually water on the plug. Is it water or is it melted aluminum?

 

[bob johnson]

Re: spark plug condition photo

Could the deposits be salt from minor water intrusion??Crumble it and taste.

I did, and you are right..absolutely no doubt the deposits are salt!!

so i do have a leak into the chamber.

the mechanic said it might be from an O-ring that motor has to seal a water passage going through the head!!

thats a little relief.

it will cost me a head gasket and some time....the bolts are not the slightest rusty....so hopefully they wont break...i might run the motor and then quickly try to take the head off...after i shut her down..


thanks for all the replies

bob