Start problem after rebuild

[Guest]

I just finished putting my bike together, but I cant get it started.
The carbs has been cleaned and everything seem to be working well.... BUT!

It will not start, it seems the gas is not getting in to the cylinders.
PS! Im trying without the gas tank installed.

The sparkplugs does not smell of gas. Dry as sahara..

Any ideas?


Info: The bike was running fine 2 months ago. Been running without problems since I got it 1 year ago.

[phrode]

Maybe I should mention it is -8 outside, and the bike is pretty cold. Never tried starting it when it is so cold.

[Agemax]

what have you done to the bike to have to "put it back together"? what are you using as a temporary fuel tank and have yo checked to see if you have a spark?
more importantly......WHAT BIKE IS IT?

[phrode]

Sorry, forgot the most important info.

GSX750E 1981 european model (GS750E).
New cams, cam chain, all gaskets new, valves adjusted and so on (as my english is a bit bad, it is not easy to describe all the work that has been done).

Yes, the spark is fine, the timing is correct (by the book).

The temp fuel tank is a ketchup bottle. There is fuel in the bowls, but it seems like the fuel is not getting in to the cylinders.

Im buying new hoses from tank to carbs today. So I can test with the tank. Hopefully, that is were the problem is.

[Agemax]

have you blanked off the vacuum port on the carbs while you are using the ketchup tank?

[tom203]

Is that minus 8 celsius? Have you tried blocking the air filter intake with something and then cranking (no throttle input) to get more fuel sucked up?

[phrode]

I have now got new fuel line, connected the tank. But now I see there is NO fuel running in the lines. All is good until I connect the line to the carbs. Then fuel stops running...

[Agemax]

I have now got new fuel line, connected the tank. But now I see there is NO fuel running in the lines. All is good until I connect the line to the carbs. Then fuel stops running...

have you put the fuel tap on PRIME and connected the vacuum pipe from the tap to the carbs?

[phrode]

Look at the pictures. Is that correct? The vacume from the carb.

If so, then all is correctly connected.

[phrode]

Picture nr 2

[tom203]

Correct- that is where the vacuum line from petcock connects. But does your petcock flow gas in "PR" spot? pull off hoses and find out.


Wait- in that petcock pic, I can't tell where your petcock vac line attaches. To me that big hose looks like fuel sender overflow drain line

[phrode]

Ok. If I put it prime, the gas flows in the line. But as soon as I connect it to the carb, the flow stops. I try starting the engine, but no fuel starts to flow...

Maybe I should fill the tank full of petrol? Right now, there is only a gallon of fuel.

[Agemax]

Ok. If I put it prime, the gas flows in the line. But as soon as I connect it to the carb, the flow stops. I try starting the engine, but no fuel starts to flow...

Maybe I should fill the tank full of petrol? Right now, there is only a gallon of fuel.

how do you know the flow stops when it is connected to the carbs? unless you have a clear/see through fuel line how can you tell?

put the tap on prime, then remove a drain plug from carb number 4 (r/h side as you sit on the bike) and see if you get a constant fuel flow draining from the carb

[phrode]

I found the fault. There was a tiny piece of rubber (from the hose) stuck in the carb (were the fuel line connects). I removed it, and now it runs like never before :-) :-) :-) :-) :-)

Just 3-4 weeks and the roads are free of snow and ice. Let the summer begin :-)

[Agemax]

I found the fault. There was a tiny piece of rubber (from the hose) stuck in the carb (were the fuel line connects). I removed it, and now it runs like never before :-) :-) :-) :-) :-)

Just 3-4 weeks and the roads are free of snow and ice. Let the summer begin :-)

well done, thats another problem solved. well spotted