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40 horse Johnson 40EL75C

S

Smith2024

New member
I’ve replaced all within the last year to year an half
points an conds
Plugs
Water pump
Rebuilt fuel pump
Fuel lines
Gas tank an primer
Rebuilt carb an replaced high speed
jet, an low speed seal around needle

She been running the best but was coming around the lake an it lost power it droped
Down to 20 mph, (gps on phone ) took it back to lake once I pulled carb off an checked for trash found nothin adjust float while I was there it was off a little, ran like crap again no power not turning full RPM so I said whatever fished anyway, started hearing bubbling in fuel tank, vent was open thought it was weird
So I started looking an pressure was coming out of the pickup side of the gas tank on the check ball area, took cap off whatever drove other side of clove wind was terrible
So I banked it got out an fished had the motor raised up (Manuel) well I fished a hour or so on way back to ramp she ran back full rpm no issue, thought she was fixed. Took it back out that weekend, seemed weaker. I’m lost on what to check, planning on checking compression, but I did take plugs out the button plug look to have water in it/
On it? May have head gasket issue not sure
Any help would greatly appreciate
 
Check magneto components, sounds like it's dropping a cylinder, clean and gap points, check condensers and load test coils and check all wires for breaks.
 
Agree, I’ve checked all the wiring, an point still looks new, an check condensers far as eye balling them not sure how to really check them other than that, far a load testing what do you mean on coils, far a sound it doesn’t sound much different running just don’t sound like it’s turning full rpm. I feel like the water gettin on the plug somehow maybe head gasket is effecting the firing a performance. Thanks for the info tho it’s def a start. Been a long drawn out deal been working all the bugs out
 
Smith2024 said:
Any idea on how to (load Test coils as stated above)
Click to expand...
You need a Merc-O-Tronic magneto analyzer model 88 or 98 to load test. Old school used for coils and condenser microfarad (capacitance) reading among other things, I have one of each in nice condition plus one for parts! I'll bet Racer has 5 of them. I test coils and condensers for anyone who needs it for free. You pay the postmaster.
 
Adjusting it so it shuts needle valve off
When bowl is full but adjust the tab so it’s flat when help upside down, my issues was a blown head gasket, found it last night. Tried to post pictures but couldn’t.
 
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