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Fass problem

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So I stop at my mailbox today and truck sounds funny.



Get in and it dies. Starts back up gets in the driveway and dies. Starts back up and gets into the garage dies. Starts back up and I park it and it dies.



That is when I notice no fuel pressure. My fass isn't working.



So I check and sure enough the fuse is burnt (15 amp). I toss in a 20 and it immediately blows. Toss in a 25 (I"m desperate, no 2nd vehicle and have to get to work). And it turns on.



So Why is the pump blowing lower amp fuses? I have a 95Gph stand alone, and it is the older motor w/ brushes. It is a few years old, and I"m worried that something is wrong or it is going to die soon.



Does anyone have suggestions on what to check?
 
Whatever you do, do it FAST. As you know, overloading a circuit is generally a very bad idea.

Could be something locking up the motor on the FASS (bearing?), which would cause a large current draw. But I'd expect the locked-rotor current to be less than the fuse value.

WKruger is right - check for a corroded electrical connector, check the wiring for a short to ground, and check the brushes.

Ryan
 
Going to look at it again tomorrow after work, but I did go and buy some more fuses, and so far it is running on the correct 15 amp fuse now.
 
Going to look at it again tomorrow after work, but I did go and buy some more fuses, and so far it is running on the correct 15 amp fuse now.
Well that's good. The fact that it didn't work, and now does, implies a bad connection to me.

Ryan
 
Well that's good. The fact that it didn't work, and now does, implies a bad connection to me.



Ryan



That is what I'm thinking also, The power connection is good, but I didn't get under the truck yet. I wish I was at home in MI w/ my nice heated garage :{



If I don't find anything I may look and see if Fass is offering an upgraded motor, as I see they have a brushless one now, and I've noticed my pump got louder last spring, but has been fine since.
 
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Ok, I need some help now. It worked all day friday w/ a 15 amp fuse in place, then this morning I started driving and it blew the fuse, I then proceeded to blow about 20 fuses going to and from work today. It only lasts for a couple mintues even w/ a 30 amp fuse.



I just took out the brushes and went over them with a scotchbrite, and did as best as I could scrubbing the brass inside where the slide. They were a bit stiff coming out, but slid nicely when I was done. I fired it back up and the pump turned on. Then I heard it stop, then it turned on again. Then off and the fuse was blown.



I NEED this truck to work so I can get back and forth to work this week!



Isn't the pump supposed to bypass and the truck should run fine w/o a pusher pump? I have read this before, but when my pump dies I can barely maintain 40mph. A few times the truck even died, so it seems my bypass isn't working so hot, or my CP3 isn't lifting like it should.
 
I NEED this truck to work so I can get back and forth to work this week!



Isn't the pump supposed to bypass and the truck should run fine w/o a pusher pump? I have read this before, but when my pump dies I can barely maintain 40mph. A few times the truck even died, so it seems my bypass isn't working so hot, or my CP3 isn't lifting like it should.



Please tell me you bought a spare pump the moment this one started acting up.



I'm not surprised the engine won't run with the pump off. Too much blockage and the CP-3 doesn't suck very well.



You're going to have to replace that pump. It's your only choice.



In the meantime, you need to think about covering your butt for work transportation. Either rent a car or call a friend who lives close.



Ryan
 
Please tell me you bought a spare pump the moment this one started acting up.



I'm not surprised the engine won't run with the pump off. Too much blockage and the CP-3 doesn't suck very well.



You're going to have to replace that pump. It's your only choice.



In the meantime, you need to think about covering your butt for work transportation. Either rent a car or call a friend who lives close.



Ryan





Nope, I didn't, I want to know why this one isn't working before I spend the money on another, they aren't cheap. I'm already looking at rentals. The shame is I have 2 perfectly good vehicles I could drive, but they are in Michigan, and I have no time to go get either.
 
FASS pumps aren't cheap. But there are less expensive solutions, like the Holley Blue (~$120).



Ryan



I may do some searching on that, I thought I read before that they wern't that reliable.



As and update to my adventure, I thought maybe the relay was bad, so I jumped the relay w/ the truck off and the pump ran for like 7 minutes just fine until I pulled the jumper.



So I started the truck and put in the jumper and wouldn't you know it, it blew the fuse. So it's like the pump is only calling for too much voltage when the truck is running.



I also pulled the FASS harness, and it looks perfect. I thought maybe there was something wrong w/ it as I noticed the fuse for my backup lights which happens to be ziptied to the fass harness in a few spots had blown it's fuse also, but I don't know when that happened.
 
So I started the truck and put in the jumper and wouldn't you know it, it blew the fuse. So it's like the pump is only calling for too much voltage when the truck is running.



That is very odd. Are you sure you weren't bypassing the fuse somehow when the truck was not running?



And remember - fuses are a current-limiting device, not voltage. The pump is demanding too much current.



Ryan
 
That is very odd. Are you sure you weren't bypassing the fuse somehow when the truck was not running?



And remember - fuses are a current-limiting device, not voltage. The pump is demanding too much current.



Ryan



Positive, I wasn't bypassing, as I left it just as I had it, then started the truck, and the pump stopped minutes later after the engine was started.
 
I had a problem with the relay being melted in side put a new one in has been fine for a week now hoping it was just a bad rely
 
I had a problem with the relay being melted in side put a new one in has been fine for a week now hoping it was just a bad rely



That is what I was thinking for a few minutes, but I removed the relay and jumped the connections, and blew the fuse, I even tried another known working relay for my air compressor. No dice.
 
OK, I guess I need to call and order the upgraded motor.



I reinstalled the harness, and cleaned the slides for the brushes again, made sure everything was good in the electrical up to the motor, and cleaned out the port on the bottom of the fass housing (the drain I guess?).



I fired it up and it blew the fuse. I figure I will put in another and get under and watch the pump. And what do I see coming out of the drain/whatever port? SMOKE! Time to get a rental and order the brushless motor.



Now, a question for diesel dan if he chimes in, I am living in Wisconsin, and I have most of my stuff at my house in Michigan, including all my FASS paperwork. I purchased the pump from Extreme diesel performance, and I can log into their site and find the order I placed, but they aren't selling FASS stuff anymore. Do I still go through them to order the upgrade?
 
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