Anyone every take apart the Fuel Pump and have it work afterwords?

[tom_nuke]

So I took out my fuel pump, troubleshooting a crappy running bike. I wanted to check the screen for debris.

So I get it apart, clean screen material with compressed air, re-assemble.

I get it all back together and now the bike won't run when giving any throttle. It does start and idle fine. I also primed it about 10-12 times using the key on/off method.

I notice after putting the pump back together and inserting into the tank, it leaks like a mofo from the stem (where it didn't when taking apart for first time).

I also noticed the cap piece didn't fit quit as snug after putting back together. Is it possible this is causing the pump to not have enough pressure?

Is this thing shot?

Appreciate any advice or comforting..

 

[FinalImpact]

Sounds like its sucking air but it could be pressure leak after the pump too.

Was there debris on the screen? A common issue is the pressure regulator gets debris in it and leaks constantly never reaching full pressure. It has an o-ring seat and will hold bits of rust. You may need to pull the assembly again and verify where the leak is.

P/R is the silver disc looking part at the top of the pump. Its just a spring in a housing with a stopper. Push it down off its seat and blow air or fluid through it to clean it. It should hold pressure the other way up to ~40 PSI.

To your point; yes. The go back and work fine. There just can't be any internal leaks.

Good luck!

 

[tom_nuke]

Thanks for the response!

I took out the pump one more time. This time minding the small o-ring between the stem tube on the cap and the base (see attached pic). I remember pushing this down as far as it would go last night, thinking it would pop out and get lost. I think this was my downfall. It was too far down and wasn't making a seal. After re-assembly, the cap piece of the pump fit more snugly. Putting the pump back in the tank reveled no leaks from the stem (what a mess that can be). Got it all back together and it fired right up after 5 primes. Pressure seems good and it will freely rev.

Good news, it's running again. Test ride also went well.

Bad news, it still has a persistent vibration. I will start moving further along in the fuel system. Tank is very clean, bike is a 2009 and was well cared for by the PO (and me). On to the injectors...

Thanks!

Tom

 

[FinalImpact]

Thanks for the response!

I took out the pump one more time. This time minding the small o-ring between the stem tube on the cap and the base (see attached pic). I remember pushing this down as far as it would go last night, thinking it would pop out and get lost. I think this was my downfall. It was too far down and wasn't making a seal. After re-assembly, the cap piece of the pump fit more snugly. Putting the pump back in the tank reveled no leaks from the stem (what a mess that can be). Got it all back together and it fired right up after 5 primes. Pressure seems good and it will freely rev.

Good news, it's running again. Test ride also went well.

Bad news, it still has a persistent vibration. I will start moving further along in the fuel system. Tank is very clean, bike is a 2009 and was well cared for by the PO (and me). On to the injectors...

Thanks!

Tom

You ever get the vibe issue figured out? Look at the sticky in the tech section... Vibration....

 

[DruGus]

Did you fixed it ?



Which part is shacking ? Tank ? Do you feel it by your seat ?


Good work assembling little cap with hole and small rubber o-ring before fixing both big parts of fuel pump ( Gotcha ! )

I ran into same trouble last weekend.