BigBlue

I've got a Holley Black on my truck. The pressure have been great. 19.2 at idle and 13.2 at WOT with comp. It's been doing great for almost a year now. Well, tonight, I get in the truck, and me FP gauge is pegged at over 30+ psi at idle. When I acclerate, it goes back down. I still have 13.2 at WOT. Is 30 psi good on the VP44? I know I don't have a warranty on the Holley cause it is used on a diesel, so I'm trying to figure this out before I have to buy a new one or something. Do yall think something is stuck open inside the pump and is causing this? I'm going to change my fuel filter tomorrow and see if that does anything. I'm also going to pull the by pass plunger on it and clean it. Maybe it got stuck closed or open or something. Like I said, whenever I accelerate, the pressures drop back to normal. It's only at idle that they do this. Any help yall could give me is very much appreciated. I'm going on a 3 hour trip tomorrow to San Antonio and won't be back until Sunday afternoon and I don't want to worry bout blowing my injection pump (I don't have a warranty on that either). Thanks for the help yall.

AlpineRAM

BB take out the plunger and see if it can move in its bore.
I have the blue and had a sticking plunger out of the box. A little bit of crocus cloth and some brake cleaner and then some engine oil convinced it.
Too much pressure on the VP44 is bad- some seals are not made for it and they can fail. (Squirting the diesel to places you don't want it )

Should be a 5min job to check the plunger

AlpineRAM

Shovelhead

Mechanical or electronic gauge?
Could be a bad sending unit.

hellotbone

Im pretty sure blue has the electronic stuff that could be it. The sticking plunger can also cause the high pressure. Hey blue you need the wildcat high flow system it makes some sweet pressure!

BigBlue

I have all electrical. VDO senders. Jamie, the high flow kit came with the conversion kit. So I'm set there. I changed the fuel filter out and it seems to have done the trick. I've got 17.2 at idle and 14 at WOT. ;D Pressures are much more stable. I'm going out of town for the weekend right now so we'll see how it does on the trip. If this doesn't work, you can bet that the plunger will be the next thing. Alpine, I had to clean my plunger also when I first put it in. Could only get 8 psi at idle and 6 at WOT. I'll let yall know how it goes when I get back from my trip. Thanks yall.

BigBlue

Well, I took the plunger out, lot of vaccum when I took it out. I looked at the plunger, and you could see a mar in it where it was sticking or something. It was a real shiny spot on an otherwise black plunger. I put some WD-40 on it and squirted some inside the bore, and now I'm only getting 10 psi at idle and less than 8 at WOT. Good news is is that I have over 8 psi at 80 mph (which is what I drove the whole trip to San Antonio). So I'm going to wait to mess with it till I get home since I don't have a lot of resources out here in the hill country to fix this thing. I had over 19 psi cruising at 80+ mph, 2200 rpm on the way up here. Anything below 2100rpm would spike the gauge. So I'm glad the pressures are down, but I didn't want them this low. I'll let yall know more later. Thanks for the help.

AlpineRAM

On mine a little bit of grease on the plunger did the trick. Maybe you had the plunger spring not inserted into the cup before. This would explain the shearing that lead to the mar on one side and the extremely high pressures.

Just my 2c

AlpineRAM

BigBlue

Like axle grease or something? Grease you'd put in a grease gun? I think I'm going to call Holley and see if they won't send me a new plunger. I think the plunger itself is to small and keeps rattling around in the bore and sticks itself. The pump has been doing great for almost the past year. Until the other day. So I don't think it was the spring not being seated right. I'm starting to save my money for a PE pump. This Holley is really starting to tick me off. I hope PE gets their fuel pump problems solved real quick.

AlpineRAM

Yep, like axle grease. Or grease gun grease- bearing grease, Lithium soap based molybdene disulphide grease.

On my Holley Blue I had to remove 2 burrs on the piston. Those burrs made the piston stick and scrape the wall. After removing the burr and sanding a 45deg phase on both ends of the pston about 0.2mm wide the piston travels freely. I coated it lightly with some grease and also coated the ends of the spring with grease a bit. Since then I am seeing 16 psi at idle and around 15 at WOT.

HTH

AlpineRAM

BigBlue

Thanks man. I just got home from a 3 hour trip so I'm going to let the truck cool down a bit before I mess with it. I'll let yall know the outcome.

BigBlue

Well, I took it apart today and the plunger was covered in stuff. So I wet sanded it with 2000 grit sand paper. Made it nice and smooth. Also rounded off the edges a very slight bit. I put a little oil on it and the spring, put it back in, and fire the truck up. Zero PSI for a second and then climbed to 10 at idle. So I take it all back apart, and notice that the plunger is still coated in a rough substance. So I run a paper towel down the bore, and pull it out, and you can see little bits of metal shavings on the paper towel and you can feel a real rough texture on the towel itself. I'm thinking something is bad wrong with this pump. I'm going to clean it out real well after the rain stops and spray some silicone in there and see if I can't loosen this thing up. Otherwise, I may be buying a PE pump real soon.

BigBlue

Well, me being the idiot that I am, I put the plunger in there backwards. I swapped it around and now the pressures are back to normal. Just goes to show you that you shouldn't work on your truck when you've been drinking and it's dark out.

BigBlue

Well. The truck is parked till I can buy a new pump. The bypass valve will not make up it's mind as to whether it want's to stick closed, or bounce around and personally, I'd rather not risk my injection pump. Thanks for all the help yall.