spare engine seeping fuel around 2 rear plugs

[ArtJ]

I started up my spare engine today and noticed gas seeping out
around the 2 rear plugs while running. I also noticed this
in spring startup. The engine sits unused in the garage.
Last winter i converted it to facet electrical fuel pump.
I by passed the opss to prime fuel system. Possibly ran it
too long ? The plugs seemed tight but i did not torque
them. Only checked with a wrench . Engine appearedto be

running fine, however did not pull plug wires.
\
is it under torqued plugs? Stuck valves or simply too
much fuel pressure? My guess is torque of plugs.
Probably won't run again for a while, but appreciate

suggestions

best regards

art

[Al Schober]

art,
You'll have to tell me what plugs you're referring to - picture would be nice.
Can't quite visualize gas leaking out around spark plugs without it pouring out elsewhere - like the throat of the carb.

[ArtJ]

Hi al the spark plugs .

I couldnt believe it either, i didn,t notice any gas pouring
from carb but didnt specifically look. It seems that flowing
from carb would be a much easier path of least resistance.

The engine only runs a few minutes twice a year

regards art

[JOHN COOKSON]

Are the little washers that come with the spark plugs present?
I don't know how you can have a leak around a spark plug without loosing compression.

TRUE GRIT

[ArtJ]

I was wondering if just not being tight enough or worn threads
in head could cause this. It was surprsing to actually smell gas

[ArtJ]

Can a running cylinder actually leak gas via loose threads
- why would it not be ignited?

[Al Schober]

I'm having a real problem accepting the idea of gas leaking out of the spark plugs. The gas is vaporized in the carb (no longer liquid) and burned in the cylinders.
You say you smell gas. I'd look elsewhere for a fuel leak.
Any chance it's water that you're seeing? I'd recommend pulling those two plugs and checking for any cracking in the head. Perhaps install new plugs (and new seal rings) to eliminate that doubt.
I can't help but think about the A4 owner that was experiencing water around the spark plugs. To shorten a long story, the water was coming from an overhead line - nothing to do with the engine.

[ArtJ]

Hi al

i was surprised as well. I wiped it off and more seeped up
around the plug. I smelled and it smelled like gasoline.
I could always be mistaken or smell a mix?

What things are possible to seep up the plug hole?
Can a stuck valve or rings
be a source? Can the water jacket ?

IF THE PLUGS ARE NOT FIRING (UNSURE OF THIS) COULD FUEL COLLECT IN CYLINDER ( 2 CYLS INVOLVED)
AND BE FORCED OUT PLUG HOLES , ESPECIALLY IF LOOSE THREADS?


0)

[lat 64]

Sounds to me like two separate problems; a too-rich fuel-air mix, and a leaking spark plug seal.

My best guess is: the choke is on for the whole run time.

Engines like to be run. Give it more time, and confirm choke is off when you do.

[ArtJ]

Since engine is not in boat, the choke spring returns it open
when not held closed it snaps open instantly.
After we sort out the suggestions i will drag the engine out again
tighten plugs better. Btw, just remembered i used some 50 to
1 outboard gas to start engine today, doubt this was the
problem . Tightening plugs - will that cure or mask the problem?

Thanks best regards

[JOHN COOKSON]

Tightening plugs - will that cure or mask the problem?
Thanks best regards

When you take the plugs out chase the threads. You can get a thread chaser at your local auto parts store.
I'm still wondering how gas got outside the engine around the spark plugs.

TRUE GRIT

[ArtJ]

Will do

is a thread chaser like a tapered thread tap?

Are they all the same size?


Best regards

[hanleyclifford]

Art - The threads are 14 mm. The tap is available at the auto stores. After you chase the threads use a shop vac to suck the junk out of the cylinder. New plugs with new gasket rings correctly torqued are a good idea. Don't forget to lightly oil the threads with light machine oil.

[ArtJ]

art - the threads are 14 mm. The tap is available at the auto stores. After you chase the threads use a shop vac to suck the junk out of the cylinder. New plugs with new gasket rings correctly torqued are a good idea. Don't forget to lightly oil the threads with light machine oil.

thanks

do you have any thoughts on why gas seeping up threads ?

Best regards

[hanleyclifford]

Art - I suggest you do a compression test.