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Sun Oct 12, 2008 8:38 am

So I've got an issue Im looking for some help with.

Details.

'86 Westy.
Idles at 900rpms

When cruising around town this morning the power was cutting out. Its as if I was lifting my foot off the gas while on the move.

There was no response from the engine when pushing the accelerator. Then it would kick back in and continue on down the road. She did this for a full half hour. When stopping sometimes she would stall and other times she wouldn't.

Any suggestions?

Sun Oct 12, 2008 8:48 am

Make sure the connections at the fuel pump are tight and the engine control module harness if full connected.

Sun Oct 12, 2008 9:08 am

For the first time, yesterday, I allowed the fuel level to get down to empty. I'm wondering if there was rust or something else in the tank that has caused this problem?

Is there a simple way to test this without pulling the tank?

Sun Oct 12, 2008 9:23 am

You could try getting the fuel pump to draw directly from a 5 gallon can of gas. Keep in mind that about 95% of the fuel it is drawing will be bypassed back to the fuel tank.

Change out the old fuel filter and cut it open to see how much crud is in there.

Sun Oct 12, 2008 11:20 am

I agree, sounds like it could be the fuel filter. Especially if you ran the tank really low just before it started. Replace the filter and see what happens. A cheap and easy thing to try.

Sun Oct 12, 2008 11:21 am

Perales wrote: I agree, sounds like it could be the fuel filter. Especially if you ran the tank really low just before it started. Replace the filter and see what happens. A cheap and easy thing to try.

OK. I need to get a Bentley manual, but here is a dumb question in the meantime.

I have located the fuel pump. There appears to be a filter, before and after it. Are these both filters?

Sun Oct 12, 2008 11:26 am

Yes, the one before the pump will be the one that catches most of the crap from the tank, so check that one first, if its real clogged, it would be good to check the other too.

Sun Oct 12, 2008 11:27 am

Yes, they are both filters. The small square white plastic one is intended to protect the pump from crud in the tank. It is likely that one that is clogged. Many of us don't even have that one. I don't. It is the big metal one that is the most important. You could try just removing the small one, and use a longer piece of fuel line and try it without as a test. I will bet that it is that one that is plugged. You probably should replace it since it may have just saved your fuel pump.

Sun Oct 12, 2008 11:30 am

I just spoke to the auto parts store, do I need the cali emisions version or the non cali emisions version?

Sun Oct 12, 2008 11:31 am

Usually when the white square plastic one gets clogged up, the fuel pump will make noise or cavitate due to inadequate flow. It should be cool to the touch.

Not good as the fuel is what cools the fuel pump. The pump costs about $160 so you wnt to protect it.

Sun Oct 12, 2008 11:32 am

http://www.van-cafe.com/home/van/page_507_285/fuel_filter.html
http://www.van-cafe.com/home/van/page_508_285/fuel_filter.html

Sun Oct 12, 2008 11:42 am

Perales wrote: http://www.van-cafe.com/home/van/page_507_285/fuel_filter.html
http://www.van-cafe.com/home/van/page_508_285/fuel_filter.html
Just crawled under and she doesn't have that white square one, its got a small metal one about 2 inches long by 1 inch around then the pump, then the larger metal fuel filter.

I fired it up and the large fuel filter that is after the pump is vibrating badly. Im guessing, its the culprit! we'll see.

Sun Oct 12, 2008 12:07 pm

First off, the small one does not seem to be stock, I will bet a PO just stuck something on there. I would get rid of that one for sure.
Secondly the vibrations in the big filter could be from the cavitating pump caused by the first clogged, non-stock filter starving the pump. The big one might still be bad, but I'll bet the problem comes from the small one. If I am not mistaken, '86s didn't even use the small filter at all.

Sun Oct 12, 2008 12:24 pm

I'd be inclined to agree with Perales' analysis. The first filter is probably clogged, but if you're going to change one, why not change both - particularly if you don't know when they were changed last. The second filter could vey well be vibrating from pump cavitation.

The PO probably put the extra filter in due to a sediment or rust problem in the tank. Or, perhaps he was just paranoid (as I. I have a second filter ahead of the pump just 'cuz.). Either way, clamp off the line between the first filter and the tank, and relieve the residual fuel pressure in the lines via the T-fitting near the distributor of your engine. The fuel line before the pump has only the pressure from the level of the fuel in the tank, but the lines after the pump contain fuel pressurised to 25-30 psi from the pump. Be aware! Eye protection/face shield would be prudent.

And, as Randy suggested, cut the filters open and "read the tea leaves". They will tell the tale.

Good luck!

Sun Oct 12, 2008 1:04 pm

Westynewbie1 wrote:

OK. I need to get a Bentley manual, but here is a dumb question in the meantime.

Oh, and Yes, buy a Bentley.
http://www.van-cafe.com/vanagonparts.jsp?pa=p&p=1210117353

And also download these three files courtesy of DogPilot:
86 Vanagon Protraining.pdf
Vanagon Protraining 86-91 Fuel Systems.pdf
Vanagon Protraining Digifant I 86-91.pdf
http://homepage.mac.com/WebObjects/FileSharing.woa...tml#file14

They are sometimes even more useful than the Bentley for certain things.