first no spark an now no gas(more test)

johnson89

Petty Officer 1st Class
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Apr 4, 2010
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244
1989 90hp....motor has been sitting for about 4 years. rebuilt both carbs. all new fuel line an new fuel filters, got motor too crank up but cylinders 2-4 had no spark at all, got a new power pack an that did not fix the problem, change the coils from 1 side too the other an plug wires ,no help...Well the other day putting everything old back on an now I have spark on all cylinders, it will throw a spark 3/4" no problem but motor is still not running on 2-4.Today I hook the gas back up an prime the bulb an with all 4 plugs out, turned the motor an can see a fine mist of gas coming out of 1-3 but no gas coming out of 2-4. I understand that this motor has 2 carb.s 1 feeds the 2 top cyl. an the bottom feeds the bottom 2..compression check all 4 cyl. 1-125...2-120.....3-130........4-120.......what else can cause this...I know 2-4 is not running by pulling the plugs wires an the cyl. are ice cold after running the motor for 10 min.s. Do I need too tear into the carb.s again or something else too look at....thanks for any help........
 

AlTn

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Mar 9, 2010
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2,813
Re: first no spark an now no gas

Re: first no spark an now no gas

diagnostics sound solid...I'd spray some fuel mix into that carb throat that feeds the "dry" cylinders and see if they pick up...this would help eliminate stuck reeds as a problem, though that's pretty remote...it sounds like either a stuck float, needle, or completely clogged main jet...you'll get it
 

johnson89

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Apr 4, 2010
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Re: first no spark an now no gas(more test)

today I went an check for spark again,very good an strong(bright blue). I started the motor an ran it for about 5 min.s then started spraying gas in the carb. on cyl. 2-4,did this for about 5 min.s, never heard an increase in sound an after turning off motor, 1-3 were nice an warm and 2-4 were cool too the touch.What could keep gas from getting too both cyl....the motor seemed to idle ok but you pull a plug from the warm side an it dies. pull one from the cool side an nothing changes.........
 

jonesg

Admiral
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Feb 22, 2008
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7,174
Re: first no spark an now no gas(more test)

Try not to run it too long, when it doesn't get fuel it isn't lubricating the cyl walls either, sounds like a reed problem if spraying fuel into the carbs doesn't make the cold cyl's fire.
 

johnson89

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Apr 4, 2010
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Re: first no spark an now no gas(more test)

well I went an got a new spray bottle,puts out a better stream an now the cyl.s are getting warm, guess it is the carbs after all, not sure what I missed, got them both back off and they seem really clean, fluid will spray thru every orfice, something must be really stoped up on both carb.s..thanks for all the help an taking the time too read.
 

jonesg

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Feb 22, 2008
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7,174
Re: first no spark an now no gas(more test)

... or the reeds.
You should be able to visually inspect them with the carbs out of the way, compare the good to the bad ones.
If possible try swapping the carbs and see if the problem follows the carb.

BTW, did you try running thin wire thru the jets?
 

johnson89

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Apr 4, 2010
Messages
244
Re: first no spark an now no gas(more test)

I will try the thin wire thru the jets..even if I swap the carb.s they are both not running on the same side 2-4..going too hook up a good spot light an see if I can get a look at the reed valves......
 
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