Fass noisy & fp dropped

[Cummins724]

My fass pump 150/150 just started sounding funny this week & fuel pressure has dropped 5lbs at idle. The pump almost sounds like it picked up air & it can't release it. The pump has been great until now & fuel is filtered 3 times before it reaches my engine. Any idea what the problem is? How hard are these pumps to rebuild if the motor is bad?

 

[LowFly]

My fass pump 150/150 just started sounding funny this week & fuel pressure has dropped 5lbs at idle. The pump almost sounds like it picked up air & it can't release it. The pump has been great until now & fuel is filtered 3 times before it reaches my engine. Any idea what the problem is? How hard are these pumps to rebuild if the motor is bad?

First thing is to check all suction connections to the pump. Make sure its not sucking any air. Might try pulling fuel from a bucket. You can fill the bucket from your return line going back to the tank. test with both the return and suction and return in the bucket, and then drain the bucket by hooking back up the return line and keeping the suction line in the fuel.



What does the noise sound like? Grinding? Gurgling? Just louder version of the normal pump noise?



Also make sure your gauge is reading correctly. I always recommend this for any pressure issue we see.



Got your SN handy?

 

[Cummins724]

Thanks for the reply DD! The noise is more of a gurgling although the pump is louder than normal. I will check all hoses again to make sure that I didn't miss anything. I will get the SN for you & check the connections etc. when I am off work on Sunday & report back. Thanks Dan.

 

[Cummins724]

The pump just started working normal Saturday night. I think it just had a little air in it. I didn't touch anything & it has been working right since Sat. I do have a question though. My pump is grounded to the framerail & the stock lp harness is powering the pump through a relay as a trigger. Should I run my pump ground to the battery?

 

[16919]

I would... ... That is how mine is grounded and I am using the harness that came with the fass.

 

[Cummins724]

I would... ... That is how mine is grounded and I am using the harness that came with the fass.

I think I will do that. Does the Fass harness use the stock lp harness as a trigger for the relay? Did you install the M4's yet? LOL

 

[16919]

I want to say that it does but I am not positive... . I can check and let you know unless someone beats me to it. No they aren't in yet... . I know I know..... I am gonna put them in here in a few weeks though. I think I am gonna check the valves and re-torque the head as well.



I have gotten 48psi out of my sps with my current set up but it usually only goes up to about 42, then the wg opens (its set at 40)... . and thats running the smarty on 4. I ran it on 8 when I first put it in and it would kiss 50psi and I messed my pants there for a minute.



Then maybe studs and ladder bars are in order if I keep going down this damn slippery slope I seem to be stuck on... ... ... ... . :-laf:{:-laf

 

[LowFly]

I think I will do that. Does the Fass harness use the stock lp harness as a trigger for the relay? Did you install the M4's yet? LOL

Yes... it uses the stock power wire for the stock pump. I would suggest moving the gnd to the BATT to get the best pos. gnd for the pump.



James,



If ya want some weekend... . run them by the house and we'll make a Sat afternoon out of it... . i love getting my hands dirty any time i can do it.....

 

[Cummins724]

Yes... it uses the stock power wire for the stock pump. I would suggest moving the gnd to the BATT to get the best pos. gnd for the pump.



.

Thanks DD... will do.