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1976 70 hp synchronize fuel and ignition system

J

jvmvjv2

New member
I have a 1976 70hp Johnson sea horse thats been sitting for about 5 years. I've done some work to it including: replace plugs, fuel pump, thermostate, clean and rebuilt carbs, replace all fuel lines, check spark and the compresion on all 3 cylinders all are good. Ive workd on cars for 10 years but I am not familiar with carbs. I also purchased the manual for this motor but I dont understand the procedure for synchronizing the fuel and ignition system. If anyone can break it down to simple terms it would be greatly appreciated. The motor runs with a slight sputter, but it runs. After it warms up I would shut it off and try to restart it. It starts in neutral but when I shift into forward it shuts off (this is while its in the water not with a flush hose or a test tank). If I continue cranking and shifting, it will eventually run in forward but it takes about 30 minutes.
 
Did you remove/clean/inspect the high speed jets in the bottom of the carbs?
I don't think I fully understand the link sync. procedure either.
I simply take pictures before I clean the carbs and put everything back exactly as it was.
I have a 73' and a 76', but I have yet to use the 76'
 
Yes. I actually replaced them. I also took pics at the start so i will put it all back to how it was originally, but its still having the same problem.
 
It is not always the " fault " of the carburetors.-----Check compression and check that you have spark on all 3 that will jump a gap of 7/16" or better.
 
Compression is good. #1-132 #2-130 #3- 130.
I also checked the spark and it the 7/16" gap with a stong spark.
Like I mentioned before I think I need to sync the fuel and the ignition together as per the manual. Its not making sense to me.
 
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