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help 4r70e johnson 4 hp.....got spark no fire

C

cazzy09jd

New member
hello i have recently aquired a 1970 4hp johnson. i set the magneto and points. i have spark but not sure if its hitting at the right time. i tried flipping the eccentric for the points to see if it was 3/8ths off. i tried starting fluid directly into the plug hole and pulled..no putt put. any help is appreciated
 
No,no-----The cam for the points is clearly marked " top " and not sure why you would flip it over.----So does spark jump a gap of 1/4" or more , yes or no.
 
My cam isn't marked and it does jump a 1/4 gap. I compression tested it finally and it only reads 45 psi on each cylinder so I'm gonna start with a head gasket. If that doesn't work guess I'm doing all gaskets and a set of standard rings
 
45 and even usually indicates a head gasket leak between cylinders. Be sure and surface the head on a glass-table with 220 grit in a figure 8 motion until it all shines the same. Pull the head down slow and even in ar least three steps using a center out pattern.
 
kimcrwbr1 said:
45 and even usually indicates a head gasket leak between cylinders. Be sure and surface the head on a glass-table with 220 grit in a figure 8 motion until it all shines the same. Pull the head down slow and even in ar least three steps using a center out pattern.
Click to expand...

I just used a 12" hobby aluminum sanding bar with 320 grit on my Johnson 3 H.P. and it worked great. 220 may be a-bit too aggressive?

Bill
 
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