Diesel Dan ...FASS gurgling and motor restarting

[Yo Hoot]

I don't know if this is a problem.

I installed my 150 system on my 2004 about two weeks ago.

It took a lot of cranking to get the fuel sucked up into the pump to where it changed sound and the truck started.

For two weeks the sound has me wondering. It's not a constant whine but an ever oscillating whine, always changing sounds. Almost like it's not fully fed.

Is this normal sound?

If there is an air leak somewhere what is the best way to find it? Where is the most common leak area? I used teflon tape on all of the brass fittings and tightened them good. The quick disconnect at the tank seemed to snap on easily. Getting the old blue retainer off wasn't easy.


Then... this morning... 37 degrees out. Started the truck. I heard the pump start and then stop. It kept doing that and everytime it restarted my inside cab lights dimmed slightly.

Should I be looking into this? I know the intake heater causes the lights to dim but I can hear the pump shut off and turn back on. After a 20 minute drive I listened and it was running continuously.

BTW: I started this thread on your recommendation.

 

[LowFly]

I don't know if this is a problem.



I installed my 150 system on my 2004 about two weeks ago.



It took a lot of cranking to get the fuel sucked up into the pump to where it changed sound and the truck started.



For two weeks the sound has me wondering. It's not a constant whine but an ever oscillating whine, always changing sounds. Almost like it's not fully fed.



Is this normal sound?



If there is an air leak somewhere what is the best way to find it? Where is the most common leak area? I used teflon tape on all of the brass fittings and tightened them good. The quick disconnect at the tank seemed to snap on easily. Getting the old blue retainer off wasn't easy.





Then... this morning... 37 degrees out. Started the truck. I heard the pump start and then stop. It kept doing that and everytime it restarted my inside cab lights dimmed slightly.



Should I be looking into this? I know the intake heater causes the lights to dim but I can hear the pump shut off and turn back on. After a 20 minute drive I listened and it was running continuously.



BTW: I started this thread on your recommendation.

This time of year the intake heaters will cause the FASS to change tone when running... . more so on 3rd gens for some reason. This is normal.



Our pump is a slave to the ECM is your harness has the relay in it. So it should be doing what the ECM it telling it to do. The pump should run for about 20 seconds if you just bump the engine.



Now if you are hearing a gurgling noise, this is normal. This is air being build up in the water separator and finally overcoming the nipple that the filter threads on to. Once this air hits the gears..... it will make a whooshing or gurgling noise. It should be random in nature... . and spaced apart. If its 100% of the time, you are sucking air or have a big restriction on the pump.



BUT i feel you are just fine from your description.

 

[Yo Hoot]

I guess my biggest concern is I actually heard it turn on and off about every 5 seconds for at least a minute or so after I had the truck running this morning. I thought once the truck was running the pump stays on. The interior lights dimming were exactly when the pump turned on every time. I'll see how it goes.

 

[LowFly]

I guess my biggest concern is I actually heard it turn on and off about every 5 seconds for at least a minute or so after I had the truck running this morning. I thought once the truck was running the pump stays on. The interior lights dimming were exactly when the pump turned on every time. I'll see how it goes.

I bet you that the pump was still running..... just the RPM dropped down and sounded like it was off..... put your hand on it next time and see... ...



Best way to confirm this is by a fuel pressure gauge... .

 

[Yo Hoot]

Thanks. I'll check and I do plan on a guage.

 

[kompressor]

I recently installed a FASS 150 on m 2004 and it has a high pitched wine, which is rather loud. I can hear it in the cab when the radio is off. Is this considered normal? I though most noise had been eliminated.

 

[Yo Hoot]

It is normal from what I gather.

I listened to mine again this morning after a cold start Diesel Dan was correct. It was the intake heater cycling that changes the electrical loads causing the FASS to sound like it was cycling on and off.

What are you guys doing for guages?

 

[LowFly]

I recently installed a FASS 150 on m 2004 and it has a high pitched wine, which is rather loud. I can hear it in the cab when the radio is off. Is this considered normal? I though most noise had been eliminated.

Our pumps will not be 100% silent... . and with the radio off and just sitting listening for the pump, then yes you will hear it in some cases. More 3rd gens than any truck. BUT normal driving and radio at normal levels should cover up the pump with out any issue to the point you will not notice it at all.

 

[JCyrbok]

Yep when the grid heaters on my truck are running the pump makes a different sound and my FP will fuctuate about 1. 5psi as they are cycling.



I bet that is what u are experiencing.



J-