Is there a simple bench test I can do to my fuel pump to make sure it is working properly?
Here is the problem, The sled will not start and run without the use of gas down the cylinders or starting fluid throu the carbs. Once it is started it will idle on full choke only. You can give it gas and it will reach peak RPM and you can turn the choke off an on as you please as long as you have it WOT. As soon as you let off it will sputter out and die and needs to be re-started with fluid or gas. I am kinda thinking that the Fuel pump needs rebuilding. I can suck gas through the pump with my mouth, but will not push gas out when you pull it over. I think the diaphram is bad or there is somthing wrong pulse vacuum on the pump. Let me know what you think
Full Version: Fuel pump diagnosis
Ak
Sounds like you have a fuel pump or fuel restriction problem. I have a spare pump that you could try out if you want to. You may not be able to get a good test without loading the motor but if you motor is acting up now you should be able to tell if a new pump makes a difference.
The easiest way to change the pump is to remove the seat and fuel tank but you likely already know that.
PM me if you want to try a pump.
Sounds like you have a fuel pump or fuel restriction problem. I have a spare pump that you could try out if you want to. You may not be able to get a good test without loading the motor but if you motor is acting up now you should be able to tell if a new pump makes a difference.
The easiest way to change the pump is to remove the seat and fuel tank but you likely already know that.
PM me if you want to try a pump.
QUOTE(Ak4life @ Jun 14 2007, 03:54 PM) 
Is there a simple bench test I can do to my fuel pump to make sure it is working properly?
Here is the problem, The sled will not start and run without the use of gas down the cylinders or starting fluid throu the carbs. Once it is started it will idle on full choke only. You can give it gas and it will reach peak RPM and you can turn the choke off an on as you please as long as you have it WOT. As soon as you let off it will sputter out and die and needs to be re-started with fluid or gas. I am kinda thinking that the Fuel pump needs rebuilding. I can suck gas through the pump with my mouth, but will not push gas out when you pull it over. I think the diaphram is bad or there is somthing wrong pulse vacuum on the pump. Let me know what you think
Here is the problem, The sled will not start and run without the use of gas down the cylinders or starting fluid throu the carbs. Once it is started it will idle on full choke only. You can give it gas and it will reach peak RPM and you can turn the choke off an on as you please as long as you have it WOT. As soon as you let off it will sputter out and die and needs to be re-started with fluid or gas. I am kinda thinking that the Fuel pump needs rebuilding. I can suck gas through the pump with my mouth, but will not push gas out when you pull it over. I think the diaphram is bad or there is somthing wrong pulse vacuum on the pump. Let me know what you think
Once running, pull off a fuel line to check for pump operation,-- could have a bad crankcase seal or- plugged pilot jets. Doesn't sound like a pump as it will run at WOT, so the float bowls are filling up.
Well I got bored waiting for some replies late last night and decided to pull the fuel pump and disassemble it. Inside I found the lower diaphram in the pump (vacuum pulse) to have a small crack and was a bit mis-shapen, I think it all makes sence. I am getting a re-build kit for it today and I will see what happens.
Thanks for the replies guys, I will let you know what happens
Thanks for the replies guys, I will let you know what happens
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