spark plug condition photo

[bob johnson]

took this plug out of my 1995 Johnson 115 yesterday...

what does it say about what is going on in my motor.

only one plug was like that...

I use the boat in the winter in rough seas, so I want to keep it running in good shape all the time..

i usually use a little extra oil, that is why i checked them...

the plugs were Ql77 something


I had some plus for a 1997 90 hp on hand Ql87.....and i installed them..

two questions, whats the spark plug saying

is it ok to substitute the plugs( in the book the 87 are the plug to use on a 115 in 97...same extact motor it seems 60 degree looper OIS)

thanks

 

[tashasdaddy]

Re: spark plug condition photo

motor calls for Champion.
88, 90, 100, 110, 112, 115 1979 - 1998 QL77JC4 or QL82C gapped at .030

 

[bktheking]

Re: spark plug condition photo

After installing new plugs check the quality of your spark on that ash covered plug's cylinder, looks like it might have been misfiring on that one plug, they should all look like the one on the right.

 

[bob johnson]

Re: spark plug condition photo

motor calls for Champion.
88, 90, 100, 110, 112, 115 1979 - 1998 QL77JC4 or QL82C gapped at .030

ok the main question really isnt the type plug.

it is the deposits on the plug i took out in the photo??

light tan heavy build up on the plug....

that is my main concern, can any tell me what is signifies on whats going on in that cylinder??

cant be good!!

and it is different than the other three plugs in appearance!! the other three look normal

bob

 

[bktheking]

Re: spark plug condition photo

It's not firing properly or it's a bad plug. They are ash deposits, if it was across all 4 i'd say try different oil but it's the one plug, that one plug isn't firing correctly causing build up.

 

[R.Johnson]

Re: spark plug condition photo

That plug on the left has been running very hot, and lean. Hard to tell from the photo, bbut at first I thought it to be a new plug until I seen discoloration on the threads. If not hot, it is'nt water washed is it?

 

[bob johnson]

Re: spark plug condition photo

That plug on the left has been running very hot, and lean. Hard to tell from the photo, bbut at first I thought it to be a new plug until I seen discoloration on the threads. If not hot, it is'nt water washed is it?

dont fully understand the water washed remark.

a little more info...

that cylinder head had a few minor issues, the thermostat haousing seems to have had a slight crack, because white powdered salt was all around that t-stat boss and ran down the cylinder head on the outside!

it left a white powder residure on the plug outer body!

when i tried to unscrew the t-stat housing, it broke almost instantly.
luckily I have a 1997 90 hp ocean pro, sitting on a stand... and so i removed the plastic t-stat from it and installed it on my boats motor.

there wasnt any bulid up of white salty stuff inside the head....looked fine!!, t-stat looked fine...

over heat warning hasnt sounded....

I havent looked at the temp gauges in a few trips, because they always have shown to be about 180...

Id like to be proactive, and if i need to rebuild a carb.....Ill do it

I dont want to fry the motor if that is a possibility...



the motor is used for duck hunting and it idles for lonmg periods of time, but has been running great!!!!!

recently, I have actually been running the boat at WOT a few times for up to 15 minutes at a time.. 5800 rpms

up to this past week, it has been to rough to dao that



thanks

bob

 

[bob johnson]

Re: spark plug condition photo

motor calls for Champion.
88, 90, 100, 110, 112, 115 1979 - 1998 QL77JC4 or QL82C gapped at .030

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

 

[R.Johnson]

Re: spark plug condition photo

By water washed, I mean is water getting into the cylinder, such as a bad head gasket. 180 degree's is running to hot.

 

[bktheking]

Re: spark plug condition photo

Correct me if i'm wrong, when a motor runs lean you don't have ash buildup like in the pic, you have no buildup as the temp of the cyclinder is increased, you should see the electrode starting to wear away. If it were water washed it would look like new? Check compression first and foremost , a blown head gasket would show up on a comp test. You are looking at one plug with a condition not all 4 so it's down to that one cylinder having an issue.

Take a flathead screwdriver and scrape the electrode of that one plug, if chucks of ash fall off it's not running lean IMO, it's not firing properly. If there is nothing to scrape off then it's running lean and may have a carb issue, the pics aren't clear enough to tell.

 

[bob johnson]

Re: spark plug condition photo

By water washed, I mean is water getting into the cylinder, such as a bad head gasket. 180 degree's is running to hot.

not 180 all the time...when it gets more than 10 pounds of water pressure it drops to 130-150....

I doubt water is getting into the combustion chamber.

i am going to peek into that chamber tonight with a scope.

a mechanic that works on my motors here, thinks I have been using too low of an octane maybe....he hasnt seen it,......just from my plug description...he doesnt have time to do a carb rebuild because he is remodleing......so he said to try new plugs and better gas and keep the oil mix a little higher... ( as i have been doing )

i pre mix my oil


thanks

bob

 

[ezeke]

Re: spark plug condition photo

The correct plug for a 60? optical ignition 115HP 1995 or newer engine is NOT a QL77JC4, but a QL78YC gapped at .030.

That is not the reason for the bad reading on the plug, but you should be using the QL78YC.

 

[bob johnson]

Re: spark plug condition photo

The correct plug for a 60? optical ignition 115HP 1995 or newer engine is NOT a QL77JC4, but a QL78YC gapped at .030.

That is not the reason for the bad reading on the plug, but you should be using the QL78YC.

I will go buy some 78s tonight..

I pulled the info from a seloc manual

said 1995 the QL 77'S
1996 the QL 82's( it might have been the second possiblity!)
1997 the QL87's

I dont remember the letters after the numbers

I had the idea that all the motros were the same from 95 on!!! till they stopped making the OIS Ocean Runner/Ocean Pros series

it seemed to make sense, because the 95 I have had the QL77's

and the 97 90 hp i have had the QL87's

which matched the manual!

but I dont have a factory manual , so i will take yopur advice and get the QL78's


bob

 

[funk6294]

Re: spark plug condition photo

http://www.verrill.com/moto/sellingguide/sparkplugs/plugcolorchart.htm

Above link give descriptions based plug color... Might give some ideas.

 

[bob johnson]

Re: spark plug condition photo

http://www.verrill.com/moto/sellingguide/sparkplugs/plugcolorchart.htm

Above link give descriptions based plug color... Might give some ideas.

is that an automotive link?

because how can you have oil contamination from ring blowby????

in any case it looks like the ash photo more than any other.

bob

 

[bktheking]

Re: spark plug condition photo

Disregard the blow by photo as its a 2 stroke.

 

[ezeke]

Re: spark plug condition photo

I will go buy some 78s tonight..

I pulled the info from a seloc manual

said 1995 the QL 77'S
1996 the QL 82's( it might have been the second possiblity!)
1997 the QL87's

I dont remember the letters after the numbers

I had the idea that all the motros were the same from 95 on!!! till they stopped making the OIS Ocean Runner/Ocean Pros series

it seemed to make sense, because the 95 I have had the QL77's

and the 97 90 hp i have had the QL87's

which matched the manual!

but I dont have a factory manual , so i will take yopur advice and get the QL78's


bob

The 115 crossflow uses QL77JC4, but not your engine.

See: http://cdielectronics.com/InstallSheet/113-6292.pdf

Also: http://continuouswave.com/whaler/reference/BRP/SparkPlugChart2008.pdf

 

[bob johnson]

Re: spark plug condition photo

so the seloc manaul is off.

because the column I read was 115 hp, 1995, 60 LV !!!

not un expected

anyway...
here is another picture both plugs came from the motor...

bob

 

[R.Johnson]

Re: spark plug condition photo

What cylinder's are those plug's out of? I don't know what that is on the left plug. Both plug's have white porcelon like they are not firing, but both have a discolored ground strap. Would be interesting to here that engine run.

 

[bob johnson]

Re: spark plug condition photo

What cylinder's are those plug's out of? I don't know what that is on the left plug. Both plug's have white porcelon like they are not firing, but both have a discolored ground strap. Would be interesting to here that engine run.

I would have considered the right plug in the pix, to be perfect!!!

clean but slightly stained in color, no deposits anywhere...no heat discolorations...

the left one has a baked type fragile build up of deposited material...

not aluminum!! it is light brown, tan-ish.

it will flake off , the camera phone wont focus on really close stuff..

the motor was running great!!

it is a heavily ladened, 20 foot Mod V with a 12 degree hull.

weighs about 1100-1200

i ran it with two adults one labrador, about 400 lbs of gear, two 9 gallon gas tanks, at 31 MPH with a 15 pitch slightly damaged S/S prop...at 5800 rpms!!!

alone with no gear, the boat would run 39 mph at 6200 with that prop.


so it seems the motor is running great!! the load dropped the rpms back into the right range!!

it idles a lot of the time, because we set and pull decoys several times a day when hunting...

I have been using about 26 ounces of oil to 9 gallons of gas....to make sure i have good oil in the motor..

i checked the plugs wondering if they were going to be too oily!! which is good by me...

Ill just clean them and or replace them, but i like the insurance of not running out of oil..

bob