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Discussion Starter · #1 ·
I just bought this thing. It had a rebuilt motor and it broke in just fine. The first time I got on it it just died like I hit the kill switch and would not restart. 2 weeks later after about 2 hours of screwing with it it finally started drove about 4 miles and it just died again and now it will not start. It's not flooded, it has new plugs, it's getting spark but it won't even sputter. Even starting fluid won't ingnite. If this motor blew I'm going to be pissed. Can a bad fuel pump fry a motor. Any comments would be greatly appreciated.
 

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I am Spartacus
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You need to do a compression check, each cylinder should be 120-140 lbs. Also while the plugs are out, shine a flashlight into the plug hole and see if you can see the cylinder walls to check for scratches. Let us know your compressions and we'll go from there.

Check the spark in as dark of an area as possible. It needs to be a bright BLUE spark. If it's orange, then it can be a spark problem. You should also be able to hear the spark jump the plug gap.
 

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Discussion Starter · #3 ·
It has compression when I put my finger over the hole. I haven't checked it with a gauge. I unbolted the fuel pump and it seemed to be leaking although it could have been coming from one of the lines. since the motor was new I was mixing some oil in with gas while breaking it in. I checked the plugs constantly and they always looked good. When it finally died the plugs looked lean. Is it possible the fuel pump was leaking and leaned the motor out and fried it. The guy I bought it from said it was the carbs that blew the motor originally. I'm thinking it was maybe the pump the whole time and now I'm F-----d.
 

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Discussion Starter · #4 ·
It has compression when I put my finger over the hole. I haven't checked it with a gauge. I unbolted the fuel pump and it seemed to be leaking although it could have been coming from one of the lines. since the motor was new I was mixing some oil in with gas while breaking it in. I checked the plugs constantly and they always looked good. When it finally died the plugs looked lean. Is it possible the fuel pump was leaking and leaned the motor out and fried it. The guy I bought it from said it was the carbs that blew the motor originally. I'm thinking it was maybe the pump the whole time and now I'm F-----d.
 

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Discussion Starter · #7 ·
Is it possible the timing went. I'm not sure how the timing works on these things.
 

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If the timing was off enough to burn a piston, it would pull your arm out of its socket when you tried to pull it over.
 

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Discussion Starter · #9 ·
No, I'm not sure how to set the timing. In a car if you don't tighten down the distributer it can come lose. I'm wondering if maybe the guy who built the motor forgot to tighten something and it won't start because the timing is way out.

Thanks for all your input S.E.G.
 

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Under the flywheel is the stator, that can be rotated slightly to change the timing (holes are elongated). You need to do a compression test and post the results. If there's not enough compression (120 lbs) it'll never start right.
 

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There's your problem. You need to take the head off and see if the cylinder wall is scratched or a ring broke. Let us know what you find. :mad:
 

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Discussion Starter · #13 ·
I'm just grabbing straws here. but could a stuck rave valve cause a compression loss I don't think they were ever cleaned there is oil leaking out of them and the zip tie is missing from the one on the side that has low compression.
 
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