Interesting timing issue...

W

wildfireblue

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Jul 19, 2010
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1979 johnson 35 hp

So here goes...

good:
-good nearly equal compression 110-115
-seems to have good strong spark both plugs
-fuel making it to both cylinders
-starts easy
-bottom plug looks like clean burn
-doesn't die unless it's at lower throttle or just above idle
-seems to rev up quickly

Bad:
-misses (mmmm bip mmm bi bi mmmm bipbipbbipmmmmmmmmmbibpbibpbi)
-wont't idle
-top plug is wet with fuel
 
BonairII

BonairII

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Re: Interesting timing issue...

Did you check spark with an adjustable spark tester? Wet plug prob not getting consistent hot spark(or it's getting no spark at all)
 
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wildfireblue

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Re: Interesting timing issue...

Thanks for your quick reply.

I tested the spark by holding the plug against the block, it looked bright while cranking.

My thoughts are that it is not consistent with engine running but I don't know how to test the components.
 
BonairII

BonairII

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Re: Interesting timing issue...

Get yourself an adjustable spark tester. Spark should be white/blue and jump a 7/16ths gap I believe.
 
W

wildfireblue

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Re: Interesting timing issue...

Tested with adjustable. It's hot enough. Maybe it's at the wrong time?
What should I check now?
 
A

AlTn

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Re: Interesting timing issue...

are you using champion ql77jc4 plugs gapped at .030"?
 
W

wildfireblue

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Re: Interesting timing issue...

Didn't check the gap but switched the plugs and the problem stayed with the cylinder.whichever plug is in the top cylinder fouls so it can't be the plug.
 
D

Daviet

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Re: Interesting timing issue...

Does your fuel pump mount to the upper cylinder, is the diaphram leaking causing the upper cylinder to flood?
 
W

wildfireblue

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Re: Interesting timing issue...

Checked the diaphram. No holes. It did look wet in and around the cylinder passage. I could have spilled some gas in removing the fuel pump. I'll check again.
 
A

AlTn

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Re: Interesting timing issue...

switch the coils and be sure both have clean grounds..does the problem remain with the top cylinder?..if so..most likely a powerpack problem..you can go to cdielectronics.com for their troubleshooting chart
 
H

Haffiman

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Dec 17, 2009
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Re: Interesting timing issue...

Pull out BOTH plugs and ground them together.
Crank the engine.
Spark should go 1-2-1-2-...
If BOTH plugs sparks at the same time, most likely a defective power pack, but might even be a 'jump' between the pins in the rubber (Amphenol) contact from trigger to power pack.
 
A

AlTn

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Re: Interesting timing issue...

forgive my bad info,wild..that should be champion L78V plugs
 
Tim Frank

Tim Frank

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Re: Interesting timing issue...

wildfireblue said:
I don't understand how tat could be the since the problem stayed with the top cylinder when I switched the plugs?
Click to expand...

Check the simple things first and verify.
You were asked what plugs and gap you have....but for some reason you won't answer that.:confused:
 
W

wildfireblue

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Re: Interesting timing issue...

Didn't answer cause I don't know. I checked the plugs off right after I switched them and the problem stayed with the cylinder and not the plug. It certainly won't hurt to check the gap so I will.
 
Tim Frank

Tim Frank

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Re: Interesting timing issue...

If you didn't put them in (and buy them) yourself, they could be anything....long reach even....
 
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