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Randy

C

cajun1957a

New member
"I have a 1978 Merc 800. Comp

"I have a 1978 Merc 800. Compression is 145-150 in all four cylinders. Number one cylinder has no fire. How do I check the spark plug wire or should i focus on the coil intead? Any other ideas as to diagnose this problem, i sure would be grateful

randy"
 
Likely the CD unit.Switch wire

Likely the CD unit.Switch wires and see if #2 wires will fire #1 coil. Elegantly simple to do.
 
don't know much about your

don't know much about your problem but to check spark you can attach a timing light to the wire. If it lights up you've got spark coming through the wire/coil.
 
Took it into a dealer and all

Took it into a dealer and all it was was the coil. I lucked out on this one cuz some of these electrical components can be pricey. What would be a good fuel/oil ratio for this older motor. The compression is good I'm told and i have heard if you run 30 or 40 to 1 rather than 50 you can get more hp. Is this tru
 
Running a heavier oil mix may

Running a heavier oil mix may help if your motor is really "tired" and experiencing "blow by" due to worn rings - but mostly it would only 1) cause more smoke 2) cost you more for oil and 3) foul your plugs causing the motor to run "worse".

Stick to 50:1
 
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