Fuel Tank Noise - Ideas? Fix?

[davevickery]

Not sure if this is any help, but I believe the fuel pump will run continuously if you jumper the connections on the relay, so maybe they are shorted now. But if so that wouldn't explain the not accelerating because even with them bumpered thou can drive it, just more gas gets returned to the fuel tank. Of check to see if you have fuel pressure. The is a little screw at a tree where they test it. You could open it a bit and it should squirt out of there pretty strong. Sorry that's all I got.

[AKWesty]

bump
_________________
84' Westy 2wd
EJ22 - 4spd - Peloquin TBD
GW +1.5 Springs
215/70-16's

www.CatchTheKraken.com

"Never go to Alaska as a young man because you'll never be satisfied with any other place as long as you live." -John Muir

[drfactotum]

Delayed thanks for the input - I've replace the fuel filter, fuel pump and fuel pump regulator - bottom line is: pump runs continuously with key in ON position - motor starts and will idle but not rev up, it dies when you open the throttle - dazed and confused

any thoughts appreciated

[edwards151]

Thanks for the update brotherdave. I ended up buying a new fuel tank with the larger 11mm outlet. Fuel pump still buzzes.... after several minutes of running. I just re-read some of 10c's earlier posts and he talks about checking the EEC system for obstructions. I might check that next. Actually, if my tank is not venting/equalizing pressure properly, wouldn't running with my gas filler cap off take care of that? I'll try driving it tomorrow with the gas cap off and see what I learn.

[brotherdave]

drfactotum, I don't know if you figured anything out yet, but the pump should not run for more that a second or two when you first turn the ignition without starting the engine. You may have an issue with the control system/relays.

For those who are debating the pre-filter, I lost a fuel pump on my 86 Westy. It happened when I ran low on gas and I assumed that the lack of fuel flow had killed the OEM VW pump due to overheating. I replaced it and when I opened up the old one, found it to be totally clogged with rust. It was all stuck to the permanent magnets inside the pump preventing any rotation. I cleaned out all the rust and she ran great and pumped well. On the down side, there was no getting the pump back together so it would stay sealed after my tear down process. Mainly just wanted to see why it had left me stranded.

Just thought I would chime in on what we're all learning. The new Bosch pump is running great after the swap. Only mod was to change the spade terminals to rings. That and the pre-filter insertion.

I am now running a clear Fram pre-pump filter and can see that I have gaseous bubbles in the filter body. I first thought they were air and dropped the filter, purged and re-installed only to see the bubbles magically re-appear. Incidentally, my tank has the larger output fitting. No whine though, even with what I presume to be cavitation causing the bubbles. Just a group FYI.

[drfactotum]

My Van quit and I had it towed home. It starts but quits immediately. The pump whirs or sings continuously when I turn the ignition on. Does this mean the pump is bad? I've replace the fuel filter before the pump but that didn't help. Any ideas appreciated.

[edwards151]

I know this is an old topic, but I spent a good hour reading the entire thread. I've got a similar cavitation issue and from what I gathered from this thread, there was no definitive solution? I'm almost ready to just bite the bullet and buy a new gas tank with the 11mm nipple, but was hoping to hear any updated knowledge that we as a group have learned. There are so many threads about fuel pump noise, fuel pump cavitation, that I feel like I could spend days searching for an answer.

A quick summary of what I'm dealing with. My brand new GW pump started buzzing loudly shortly after installing it. I decided to ignore it until if finally died. The pump was less than two months old with under 1000 miles on it. GW replaced it with a new one. Decided to have a mechanic look it over and put the new pump in. Sure enough, the new pump started buzzing almost immediately. The mechanic suggested I install a square pre-filter to protect the pump. His theory was that junk from the tank was causing the obstruction and that the junk was also going to ruin my pump, so the pre-filter would protect it. (I converted my 85' to the newer filter configuration a couple years ago - no pre-filter, just the larger can post-pump filter.) Anyway, I drove the van home and pondered what to do. I decided to first switch out the post-pump can filter with a new one. Immediately the noise went away! Thought I had the problem fixed - it seemed that the old filter was plugged and causing the pump to work harder. Well, a day later, the noise came back, and has been coming back intermittently. It never happens right after startup, usually only after I've driven it for 10-15 minutes. But after I've parked it and start it up again, it's quiet for the first 10-15 minutes again. So that tells me there isn't an obstruction, otherwise wouldn't it be noisy all of the time? So it seems to me that even though replacing a 30 year old gas tank isn't a bad idea, it may not fix my problem.

If there is another thread with updated info and answers to this puzzling problem affecting so many of us, I'd appreciate a link to it!

Thanks!

[Rodknock]

I went shopping for a gas tank and found one made by Spectra Premium that has the 11mm (3/8") outlet to match the inlet of the fuel pump. Put the new tank in and the noise is gone! Finally resolved this long standing issue. The part number for the Spectra Premium fuel tank for '86 to ;91 Vanagons 2WD is commonly listed as VW3C, and I got mine from... http://www.tanks-to-pans.com/site/823208/page/305723

[Rodknock]

After a little camping trip this weekend, and getting tired of hearing that fuel pump cavitation, I decided to try 2 feet of 11mm hose after the pre-filter and before the pump. Made no difference. Cavitation noise still there. I guess the T-off the return line and into the inlet line to the pump is the next thing to try.

I also put a long screwdriver up to my ear and the other end on the inlet and outlet fuel lines of the pump. The outlet line noise was much louder than the inlet line, or the pump for that matter.

[msinabottle]

Mine's about there now. Chris's ideas are good, though, I may re-do the hoses with new, good, F.I. hose and those smooth NAPA clamps, at which time I'll get the lengths to the 'tencent' specs.

Best!
_________________
'Winston,' '84 1.9 WBX Westy
Vanagon Poet Laureate: "I have suffered in
many ways, but never, never, never in silence."

[foodeater]

I was having an issue with cavitation (noise) in the fuel pump and I remembered 10¢'s idea for putting a longer length of hose between the plastic pre-filter and the pump. for my application it has worked. I moved the pre-filter closer to the tank. Its now only about 2 inches away from the tank. I put in about 6 inches of the larger diameter hose between the pre-filter and pump. and the noise is gone!!!
_________________
89 Bluestar-2.5 Subaru Powered-RIP
'84 Westy Tiico-daily driver-sold
'82 Caddy diesel-sold
'87 Vanagon Syncro-RIP
'81 diesel rabbit-sold
'82 Vanagon auto-RIP

[pushkick]

so given you have taken a long trip i guess the noise issue is no longer a issue?

[msinabottle]

Thank you for the additional data about your mod and problem. We're still collecting it and we'll figure it all out.

Best!
_________________
'Winston,' '84 1.9 WBX Westy
Vanagon Poet Laureate: "I have suffered in
many ways, but never, never, never in silence."

[82WestyMan]

one last thing to add....

that intermitten hesitation i was hunting down and thought I cured with the gas line mod, well...
i started my trip and after about 5-6 hrs it started again... a couple of times it just killed the van but restarted before I could come to a complete stop....
then in the middle of MS, in the middle of nowhere... the van just died and wouldn't start, turned it over and no smell of gas at the tailpipes....sat there for a few, thought about all the things i had done and
a year ago i had put in a new dual relay and thought, you know, that's one thing i had never changed... and it turns out i had two (used) extra's with me...
long story short... it took twice as long to unpack the tools, parts and van enough to get at the engine compartment and repack it all then it took to change the relay...

not a hint of the problem since....
just goes to show you just because its new doesn't mean it's good
_________________
"The floggings will continue until morale improves"
"I never did give anybody hell. I just told the truth and they thought it was hell" - Harry S. Truman
82 Westfalia - w/ a Raby 'Camper Special' engine

[msinabottle]

Rodknock has put it well, the final configuration of the tee/return fix has yet to be settled. We just need a few more experimenters. I did check the tank on the passenger's side, and the hoses, and SAW no leaks, I'll have to look more thoroughly. That's where I smelled the gas, but you should also note that it was winter-formula gas (with Sta-Bil and HEET) on a very hot summer day. There had to have been SOME vapor.

The good news is that the howling seems to have stopped for the moment, of course I clouded the picture by applying too many variables. Winston had less than 5 gallons in his tank, I'd run him VERY low on the last tank, partly to see how far he'd go on a tank, then emptied 5 gallons from a leaking can into him just to keep him moving.

I decided that just the tank being low might have something to do with the problem, so I filled him with his usual mixture of regular unleaded (I'm old) and Marvel Mystery Oil--and a can of BG44K, at <gulp!> $24! I thought that might devout and gunk inside the pump or the injectors, it's superb stuff and it has been a long time since I've used it.

At any rate, though, and I did listen, the pump was quiet. It wasn't HOT at the worst of it, but it was noisy and vibrating. The smell of gas wasn't profound, I should note, at least not until I changed the old pre-filter!

I'll have a good long look at things. We did inspect all hoses and tanks when we replaced the tank itself, and we did use most of a Van Cafe tubes and seals kit in the reassembly.

Best!
_________________
'Winston,' '84 1.9 WBX Westy
Vanagon Poet Laureate: "I have suffered in
many ways, but never, never, never in silence."

[Alan Brase]

[Rodknock]

The title of this thread should be "Fuel Pump Noise." Understand the noise we are talking about here are bubbles (cavitation). A constant hum/whir/ringing/singing of a pump, loud or soft, is not the same as the sound of cavitation (bubbles) in the fuel pump. Note also that you can really hear the cavitation while stopped and idling, hard to hear when crusing along.

Msinabottle, check the hoses at the bottom of your expansion tanks, I just replaced all four and I get no gas smell now (re-sealed my tank last year). They can leak vapors ever so slightly.

I don't know if everyone with a 7mm tank outlet has the cavitation problem, but I do know that many of us, even with new clean tanks, filters, & pumps are very clearly having this problem. I beleive cavitation is the reason my Bosch fuel pump lastetd only 12,000 miles. Cavitation is bad for pumps, period. I know from my own testing that if I put a 7mm inlet to the pump (take the gas tank totally out of the equation), I get cavitation. With an 11mm inlet, no cavitation. 82Westyman confirmed that if you tap off the return line and into the pump inlet the cavitation goes away. The only question now is whether to keep the return line hooked up to the tank, thus creating the possibility of drawing air when fuel levels are low. VW engineers hooked the return line to the tank for some reason, and I beleive strongly it is to cool the fuel. In 1/4 mile drag racing, we iced the manifold to keep fuel/air mix supply cool as possible. I am leaning toward putting a check valve between the return line T and the tank return inlet to avoid the air drawing problem, assuming I can find such a check valve.

[Alan Brase]

[msinabottle]

Very sorry about the rod and knock thing.

The new tank was absolutely spotless inside and out when I got it, I looked into it very carefully, capped all openings, and sprayed it with Mercury Corrison Preventative--similar to WaxOyl-- to keep the exterior from rusting.

I did smell gasoline when I was trying to figure out what was going on, it seemed to be coming from the fill cap. It was quite a hot day--hottest of the year so far--and he'd been parked in the sun, so I figured it was just expansion and vapor.

Best!
_________________
'Winston,' '84 1.9 WBX Westy
Vanagon Poet Laureate: "I have suffered in
many ways, but never, never, never in silence."

[Alan Brase]