1974 chrysler 55 hp #555hg fuel leaking out exhaust port wont start

aquabob68

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ive got spark on both plugs and fuel leaking out of exhaust, 2 stroke motor, cleaned carb, got fuel in bowl float works, plugs barely wet, new spark plugs, compression test 140 on bottom 145 on top, engine will not start, any ideas on what the problem could be? appreciate any help to get this chrysler running.
 

aquabob68

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Re: 1974 chrysler 55 hp #555hg fuel leaking out exhaust port wont start

im not familiar with 2 strokes but after studying 2 stroke engines from you tube videos im thinking ive got my plug wires crossed, this is an old boat ive bought and restored but customized for fishing its a 15 foot tri hull and my first boat, i am former navy so i know a little bit about being on the water, but not much about 2 stroke motors. i will swap wires on plugs tomorrow and see if it fires up, the ignition system is like that of a lawn mower, coils, points, i replaced points, with atom purple ignition modules and have spark but if i i rotate flywheel where magnet is over coil then look through spark plug holes shouldnt i see piston at tdc and know which wire goes to which plug from the coil? as far as i know there is no way to set timing on this type of ignition?
 

Nordin

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Re: 1974 chrysler 55 hp #555hg fuel leaking out exhaust port wont start

Shared flywheelkey. The spark should come when the piston is just at top dead center on both cylinders. If the key is shared that would not happen.
 

jerryjerry05

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Re: 1974 chrysler 55 hp #555hg fuel leaking out exhaust port wont start

TOP DEAD CENTER is found by removing the top plug.
Take a small screwdriver and put it in the hole.Slowly turn motor over (by hand) till screwy stops comming out.
Then at the front of the motor should be a timing mark.Above the carb.They should line up.
If not then it's possible the flywheel key is sheared.
The timing mark should be a line a couple of inches from the TDC mark.

Gas comming from the port??? Usually the fuel pump diaphram has a hole or tear.
Clean the carbs,make sure the float is set right and rebuild the pump.J
 

aquabob68

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Re: 1974 chrysler 55 hp #555hg fuel leaking out exhaust port wont start

Shared flywheelkey. The spark should come when the piston is just at top dead center on both cylinders. If the key is shared that would not happen.

the flywheel key is good if i turn the flywheel by hand it turns with the crankshaft and even with starter engaging it turns the crankshaft if it were broke it would spin around the crankshaft...so i swapped plug wires around on the plugs thinking i had them back wards but still no go, i got fuel got spark, but fuel still leaking out exhaust port maybe im flooding it cause of something else like fuel pump or maybe timing off
 

aquabob68

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Re: 1974 chrysler 55 hp #555hg fuel leaking out exhaust port wont start

TOP DEAD CENTER is found by removing the top plug.
Take a small screwdriver and put it in the hole.Slowly turn motor over (by hand) till screwy stops comming out.
Then at the front of the motor should be a timing mark.Above the carb.They should line up.
If not then it's possible the flywheel key is sheared.
The timing mark should be a line a couple of inches from the TDC mark.

Gas comming from the port??? Usually the fuel pump diaphram has a hole or tear.
Clean the carbs,make sure the float is set right and rebuild the pump.J

i put a screw driver in and when piston reached top, pushing out screwdriver, i looked at the timing mark above the carb, i noticed there is no mark on my flywheel, the key isnt sheared, cause the flywheel doesent spin around the crankshaft just to make sure i pulled the flywheel and key and points cam are like new, also the flywheel can only go on one way with the key so there is no adjustment of the flywheel it goes where it goes with the key slots, i dont know if my prob it with spark timing or flooding, fuel pump looks clean, filter clean, carb clean plenty of gas in bowl, gas oil mix at 3 oz per gallon=50:1 if my calcs are correct, only thing is i replaced points with purple atom ignition modules, im wondering if those modules are the prob but i got good spark but maybe not in time idk....question if the fuel pump has a hole or tear would it cause pump to pump too much? usually if a pump has hole or tear it wouldnt pump enough, i think im getting too much fuel flooding it or spark timing off
 

Nordin

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Re: 1974 chrysler 55 hp #555hg fuel leaking out exhaust port wont start

If there is a hole in the pumpdiaphragma fuel passes direct into the cylinder and the cylinder get to far rich fuel/air mix and the plugs get wet. The spark can not fire the fuel/air mix. Check the diaphragma.
 

jerryjerry05

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Re: 1974 chrysler 55 hp #555hg fuel leaking out exhaust port wont start

The key can be sheared and still turn the flywheel and crank..
It has 95# of tourqe on the nut.
Someplace on your flywheel are timing marks.
Might be 2 seperate marks or 3 marks together and a single mark.
For some reason I can't post pics.I have a couple of the timing marks.
 

rickryder

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Re: 1974 chrysler 55 hp #555hg fuel leaking out exhaust port wont start

thanks very much for the service manual, that is awesome...i still cant figure out why my motor wont run tho but that manual is nice to have thanks again.

Your welcome Bob.
 

aquabob68

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Re: 1974 chrysler 55 hp #555hg fuel leaking out exhaust port wont start

If there is a hole in the pumpdiaphragma fuel passes direct into the cylinder and the cylinder get to far rich fuel/air mix and the plugs get wet. The spark can not fire the fuel/air mix. Check the diaphragma.

thanks for that info, i pulled fuel pump off and diaphram was dry rotted but didnt see it cracked all the way through to leak also noticed area behind diaphram was bone dry, i dont know if that is the problem for it flooding but i need to replace it and the gasket i have new one ordered.
 
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