Spark plugs splash deposits (glazing)

jtcarter

jtcarter

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I'm running a 175 Evinrude Intruder motor 1995. I'm getting splash deposits on my plugs or glazing as they call it. What would cause this? Could this be the reason i can't seem to find the 400 rpm's i've been missing forever? The plug indicator said it's caused by misfire. I'm running champion QL78YC plugs.
 
tashasdaddy

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Re: Spark plugs splash deposits (glazing)

very possible. many things, a full tune up would most likely correct. timing, carbs, compression, linc n sinc, running fuel higher than 87 octane.
 
jtcarter

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Re: Spark plugs splash deposits (glazing)

tashasdaddy said:
very possible. many things, a full tune up would most likely correct. timing, carbs, compression, linc n sinc, running fuel higher than 87 octane.
Click to expand...

Idles low and it's probably on the rich side. I need to set those carbs, needle valves, one by one is irritating.

linc and sinc is good.
Carbs have been gone through, fresh kits less than a year old.
Filter is new also.
Compression is good 100 is my lowest cylinder 105 my highest.
Timing was set by Evinrude timing tool. I'm not sure you can really set the low end with the tool. It has a detent tab for idle. Running those needles in brings the idle up.
Never used anything other than 87 octane. Might give 89 a try if it helps. I only run real gas, no ethanol.


One thing i forgot to mention, i've been running a electric fuel pump for the past year or so, 7 psi pump.Could that have anything to do with the splash deposits?
 
jtcarter

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Re: Spark plugs splash deposits (glazing)

What's the odds both stats are bad? Because it's happening on both sides. Although it's more noticeable on port side. Here is a picture of exactly what my plugs look like.

splashfouled.jpg
 
tashasdaddy

tashasdaddy

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Re: Spark plugs splash deposits (glazing)

salt water motor? the odds are very good, they got eaten up with salt.
 
jtcarter

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Re: Spark plugs splash deposits (glazing)

Only freshwater. You can put a new set in it, run it hard up lake, pull the plugs and you already see those deposits forming. It almost seems like the motor isn't coming up to temperature like Faztbullet said. I'd almost go along with that except i changed both stats a couple of years ago. Come to think of it that's about when i noticed the rpm loss. Guy at the shop said the temperatures are coming up. It has fast start and it always idles down after a minute of that. Might have got a hold of two bad stats or it's something else all together.
 
jtcarter

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Re: Spark plugs splash deposits (glazing)

What type of heat range is normal for that engine and does it vary from port to starboard?
 
jtcarter

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Re: Spark plugs splash deposits (glazing)

These thermostats on this motor are at the top of the head. A spring holds the thermostat in place. Is it possible the springs are weak? Accelerating and the water pressure goes up they're giving just enough to let water past?

I'm going to get one of those temp sensors at harbor freight. I imagine the shop checked them while it was running on a hose, i bet the readings are different on the water. I took the cowl off the other day and i could just about leave my hand on the port side for about as long as i wanted without it burning me.
 
Faztbullet

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Re: Spark plugs splash deposits (glazing)

Several questions:
What type of oil are you using?
Are you mixing 50:1 ratio correctly?
Do you do a lot of idling or trolling?

If you have a regulator turn it down to about 5-1/2 psi as it may be causing carbs to slightly flood and wash cylnders at idle(your low idle and overrich problem) and softening of carbon in combustion chamber thus your "splash" deposit.
 
jtcarter

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Re: Spark plugs splash deposits (glazing)

Faztbullet said:
Several questions:
What type of oil are you using?
Are you mixing 50:1 ratio correctly?
Do you do a lot of idling or trolling?

If you have a regulator turn it down to about 5-1/2 psi as it may be causing carbs to slightly flood and wash cylnders at idle(your low idle and overrich problem) and softening of carbon in combustion chamber thus your "splash" deposit.
Click to expand...
That was the only other thing i could come up with also is that that electric fuel pump was causing a flooding problem at low idle. I'm putting the OMS pump back on it today. Low speed needle valves are probably out farther than they should be.

The fuel pump i had on it ran 7 psi never dropping pressure. Flooded plugs would explain a wot rpm loss i would think, either that or temperature.

I run pennzoil and i don't really do a lot of idling, but i do idle some. 16 ounces for every six gallons of gas. I always put my gas in first also and add oil after.
 
jtcarter

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Re: Spark plugs splash deposits (glazing)

Replaced fuel pump and went back to OMS pump. Motor seems to run a lot stronger with the oms pump on it. Still only turning around 5200 rpm's, but you can tell it's much more responsive in mid range.

I have a question. I've been running this motor with a 7psi electric fuel pump for probably at least a year and a half. I only make short runs and idle quite a bit. I'm thinking maybe i have some rings sticking due to carbon build up from slightly flooding the plugs at idle.

Put in a new set of plugs and #2 #4 #3 are still getting the splash deposits on them.

Should i do a full decarb at this point? Or just add some seafoam to the gas and try to free them up that way?

Pretty happy with the power gain. I also have some height in my jackplate i could play around with.

It just about has to be blow by on the pistons at this point but compression is good. I'm just wondering if it might remedy itself over time or should i due the full decarb asap?

18 1/2 foot hydrasport on light fuel load running 62.5 mph at 5200 rpm. Love to see what it would do at 5500 or 5600.
 
Faztbullet

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Re: Spark plugs splash deposits (glazing)

I would add some decarboning agent to fuel and spray a entire can of "power tune" in engine and let set over night..
 
jtcarter

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Re: Spark plugs splash deposits (glazing)

OMC engine tuner? Pull the plugs and spray it in? Seafoam to gas or startron, ring free?
 
Silvertip

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Re: Spark plugs splash deposits (glazing)

I hope you have a "safety - dead engine" switch in that electric pump circuit. Without such protection you risk a serious explosion/fire hazard. Turning the key off does not constitute a safety switch. 7 psi also sounds high and that can overpower the needle and seat in the carbs.
 
jtcarter

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Re: Spark plugs splash deposits (glazing)

Silvertip said:
I hope you have a "safety - dead engine" switch in that electric pump circuit. Without such protection you risk a serious explosion/fire hazard. Turning the key off does not constitute a safety switch. 7 psi also sounds high and that can overpower the needle and seat in the carbs.
Click to expand...
Re read, went back to OMS pump yesterday. I believe you might be correct since it has a lot more throttle response now. Just trying to get all the carbon out of it now from flooding the motor for a year and a half.
 
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Re: Spark plugs splash deposits (glazing)

I know this is going to sound dumb but have you switched fuel brands since this prob started ? There's a reason for asking.
 
Faztbullet

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Re: Spark plugs splash deposits (glazing)

OMC engine tuner?
Click to expand...
Yes or Merc Power Tune...

Pull the plugs and spray it in?
Click to expand...
Yes , spray 1/2 a can into carbs while running and shut off,trim up and remove plugs and spray remainder into cylinders and let set overnite....

Seafoam to gas or startron, ring free?
Click to expand...

Quickleen, Ring free, Carbon guard...I personally dont like Seafoam.
 
jtcarter

jtcarter

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Re: Spark plugs splash deposits (glazing)

boobie said:
I know this is going to sound dumb but have you switched fuel brands since this prob started ? There's a reason for asking.
Click to expand...
Might have run some Ethanol E10 when i first got it. I've ran real gas for probably two years now. I know the E10 runs hotter, has my mind thinking.
 
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