Difficult Cold Start

Bosunsmate

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Apr 7, 2012
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Check your spark plugs for different colours, see if any look different which will indicate a faulty cylinder or if they are all are poor colour indicating a general problem.
I doubt you heard a knock from the engine based on your tdc test
 

Tripp Halbert

Petty Officer 1st Class
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Jul 30, 2013
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I ran the motor with 100:1 in tank and still ran at good temps buttt...

I checked the plugs afterwards and cylinder #2 (one of the idle cylinder of 2+2 system) and cylinder #3 (one of the mid - wot cylinders) had unburnt black oil on the plugs.

With that being noted, I will run straight gas in it on Saturday and see if things change. Any other suggestions?

Bosunsmate if I had any play on the pistons would it have been obvious when pushing on them?
 

Bosunsmate

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Apr 7, 2012
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I ran the motor with 100:1 in tank and still ran at good temps buttt...

I checked the plugs afterwards and cylinder #2 (one of the idle cylinder of 2+2 system) and cylinder #3 (one of the mid - wot cylinders) had unburnt black oil on the plugs.

With that being noted, I will run straight gas in it on Saturday and see if things change. Any other suggestions?

Bosunsmate if I had any play on the pistons would it have been obvious when pushing on them?


I find that the best way to check for bearing play as i find any movement obvious especially any difference between cylinders.

Clean those plugs, ive never being near that motor but unburnt black oil on a plug sounds like a clear signal somethings wrong there- carb overloading, over-oiling not burning/sparking
 

Tripp Halbert

Petty Officer 1st Class
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Jul 30, 2013
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202
Yea I agree. Hopefully it's just the mixed oil on top of the injected oil from the gravity tank
 

Bosunsmate

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Odd that its only on those cylinders, i wouldnt stress too much if it is not caused by the mixed oil on top as you then know where to concentrate your efforts.
Im not sure if you checked whether the bulb stayed really tight with engine off, if not maybe its just a leaky carb valve on that cylinder
 

Tripp Halbert

Petty Officer 1st Class
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Jul 30, 2013
Messages
202
Yes I checked and forgot to post it here. It is staying pretty firm but not rock solid. If I squeeze it while idling in the river it will rev up?
 

Bosunsmate

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Yes I checked and forgot to post it here. It is staying pretty firm but not rock solid. If I squeeze it while idling in the river it will rev up?
That normally happens if your fuel pump is stuffed, i cant see how that relates to an oily sparkplug unless its running lean in there due to loss of fuel and the oil feeder is therefore overloading oil in but ive never worked on that motor
 
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