# Spark plug Tecumseh HMSK80?



## HS80

I have an Tecumseh HMSK80 with a Campion RJ19LM spark plug. Is this correct plug or should it be Champion RJ8C?


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## uberT

It looks like the Champion RJ19LM is the correct plug:

Tecumseh 4-Cycle Spark Plug Conversion Chart


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## 43128

it is the correct plug, but the ngk br2lm is a much better plug, and cross references to a rj19lm


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## HS80

43128 said:


> it is the correct plug, but the ngk br2lm is a much better plug, and cross references to a rj19lm



Thanks, will order an NGK plug.


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## HS80

http://vid71.photobucket.com/albums/i134/talfheim/IMG_5875.mp4
No good... 
Runs like an old donkey..


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## Normex

HS80 said:


> http://vid71.photobucket.com/albums/i134/talfheim/IMG_5875.mp4
> No good...
> Runs like an old donkey..


 From your Vid I assume you had the spark plug off and touching it near the spark plug hole, if so you have a nice blue spark which should work well once the plug is back in. Since I saw you had another thread pertaining to your engine, is it because the engine runs bad? Has the carb been cleaned?


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## HS80

Changed spark plug. 
Cleaned carb, and still runs bad. I have never had a tecumseh that worked perfect for years


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## db9938

Well, it would appear, with the flame out of the exhaust, that your valves may need to be lapped and adjusted. As I sure that you are aware of, the flame and rough operation are a good indication of lost compression. I know that you posted previously, on what you've done so far. I am not sure that you have dug into it, thus far. And if you have the ability to conduct a compression test, I might suggest that to verify compression. 

Another possibility, that the carburetor may be running too rich, which is a simple adjustment. A rule of thumb, is to screw the mixture adjustment screw all the way in, and back out 3 revolutions. Or, you could start with turning the adjustment in 1/4 of a turn, while it's running to see if it improves. 

"runs like old donkey" I can honestly say that the first time I've heard that.


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## HS80

I think compression looks good, not measured but works fine. Engine start at 1-3 pull. There is no adjustments on the carb... 

Engine type:
http://i71.photobucket.com/albums/i134/talfheim/IMG_5863.jpg


Engine running:
http://vid71.photobucket.com/albums/i134/talfheim/IMG_5880.mp4


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## db9938

Well, it's either a compression leakage issue, or the carburetor is not able to maintain the proper fuel air ratio. With these emissions regulated engines, they are particular to having all the internal passages clean. 

I've found that an inexpensive ultrasonic jewelry cleaner works great. Others will recommend a chemical bath type, and they do work, but I'm completely unfamiliar with what to recommend, as I've never been to Norway and do not know what you have available.


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## HS80

I take it with me at work. Have a huge washer on the ship i work on. 
I think i have found the problem, its no clearance on the exhaust valve...


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## Normex

HS80 said:


> I take it with me at work. Have a huge washer on the ship i work on.
> I think i have found the problem, its no clearance on the exhaust valve...


 You are getting closer it seems, there are good youtube vids for anything valves on HM80 so here's one to start with and you can find one for lapping. Good Luck


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## HS80

Thanks.
When adjusting these valves you have to take of a little bit of the stem?
My big question is how to get of the valve retainer?


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## Normex

HS80 said:


> Thanks.
> When adjusting these valves you have to take of a little bit of the stem?
> My big question is how to get of the valve retainer?


You have 2 threads on the same subject, you might have better success on the other thread with the Youtube links given there.


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