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Spark Plug Gap 1973 85hp Johnson V-4

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yahoo50

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Can anyone please tell me the spark plug gap for a 1973 85hp Johnson V-4. Ordering a Service manual today,but already have the plugs.
Thanks,
Ernie
 
Re: Spark Plug Gap

Sparkplug gap from 0.030" to 0.035"---------------Not really as critical as some may think----------------Do you have running issues with the motor.
 
Re: Spark Plug Gap

I actually do. It runs rough when at idle, (cuts out alot but never dies) but when in i go to the lake and give it gas it smooths out.
Even at wot it runs good. I dont know if I want to mess with it or not? I am for sure getting a manual first.
Any Ideas of what could cause the rough idle? Probabally LOTS OF THINGS .....
Thanks Racerone
Ernie
 
Re: Spark Plug Gap

These motors have a history, like anything else.-----------------The first step is a compression test.------------The numbers should be even cylinder to cylinder, the actual comprssion # does not matter.--------------Next is an ignition performance test.The spark should jump a gap of 7/16" or better on each cylinder.----Once you have that info the repair process can begin.------It may just be that the idle speed needs to be increased.
 
Re: Spark Plug Gap

When I get my manual I will check that out and if i still have time this season i will look ya up.
If not I will for sure look ya up next season!
Thanks again,
Ernie
 
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