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alpinekid 10-21-2021 01:29 PM

working on siphoning diesel out of the tank.
Back story:
1992 ford 7.3l in a E350 chassis.
I've been a bad boy, I let the old bus sit for a couple of years in the backyard. It has a bad starter and I just didn't get around to change it until just now.
The bus starts and run, I've let it warm up at idle and it sounds fine. The issue is when I rev it up a little, like moving in back and forth a few feet and then quickly take my foot off the peddle; it immediately dies. It always starts right back up.

I went to the "google school for diesel mechanics " :biggrin:and they said it may be as simple as water in the fuel; which is really possible since its been sitting for 2yrs and/or a stuck or gummed-up something in the IP. I'm also worried about bugs in the tank causing me a problem in a few miles.
Could they be right?

I'm going to change the fuel filter, I can see it but not looking forward to removing it. but before I do I wanted to get a look at the fuel in the tank; so I thought siphon some out would work. I can get the hose in about 4ft and then it hits something that sounds like a door of some sort, it "tink" when I push the hose against it.:banghead:

Is there an anti-siphon thing in there or some kind of divertor that prevents siphoning?
Has anyone had any luck doing this?

I also notice a drain plug in the tank. What kind of mess or problem can I have if I try to loosen that to get a look at the fuel. The tank is about 1/2 full by the gauge. I thinks that is about 15gals but i'm not sure what facts I used to arrive at that number ie. I'm only assuming the tank is 30gals.

Looking for any advice or wisdom that you might have.
My plan was to look for dirt, bugs etc, add some kind of fuel additive, change the filter, run it for while and then change the filter again to get a real good look at what is/was in the tank. I'm hoping that the additive will cover me if there is something stuck in the IP.

Can you suggest any improvement in the plan?

Booyah45828 10-21-2021 01:59 PM

IDI engine as in your signature?

Your issues sounds like the delivery valve in the injection pump is sticking/gummy.

You can try running some atf through it to see if it clears it up, but if that doesn't work, a replacement injection pump is next.

What I would do is remove the filter and inspect the fuel in it for water, crud, or poor quality. Then, install a new filter prefilled through the outer holes with atf, add a grey bottle of diesel kleen to the tank, and then fill the tank the rest of the way with fresh diesel. Start it up and let the engine idle for a minute. After the minute, shut it off and let it sit overnight. The next day, take it on the road and drive the thing around like you stole it. The important part is driving, as idling unloaded will never work the delivery valve enough to clean it. It needs a load placed on it.

Some tanks have anti-siphon features, and some are just difficult to siphon due to the bends in the filler neck. I would not remove the drain plug on the tank, unless you're certain the fuel in the tank needs drained. Too often trying to remove that plug will damage the plug/tank and you'll end up scrambling trying not to spill the entire contents of the tank on the ground.

You can change the filter again after all of this if you'd like to inspect it again, but if the fuel is ok, it's likely not necessary.

alpinekid 10-21-2021 04:50 PM

thanks for the detailed process, I never would have guessed AFT; That automatic transmission fluid right. Any special kind?
Will the engine start on it or will it just crank until diesel get to it from the tank?

Booyah45828 10-21-2021 05:18 PM

ATF, yes automatic transmission fluid. Cheap dex3/mercon works, so does type f. No need to get fancy. Engine will start and run fine on it, might notice a different tone to it, but it's a petroleum based oil and burns very similar to diesel fuel.

Just be sure to put it in the outer holes of the filter, not down the center.

alpinekid 10-27-2021 05:27 PM

status update on fuel issues and siphoning
Thanks for all your help.

I've given up on getting a siphon hose into the tank. I'm either hitting the last bend right above the tank or some kind of diverter plate in the tank.
I've now turned my attention to changing the filter and just looking for crap coming out of the tank.

What a challenge getting the old filter out. I got it unscrewed with only a fair amount of effort but getting it out from on top of the engine is a different story. After disconnecting two major bundles of wires, moving the prime vacuum line and much wiggling for 1-1/2 hrs its out.
I was able to siphon the fuel out of the filter before I started rocking it around to get it out, so glad I did that. At lease the siphon system I created didn't go to waste. I'll put the ATF in just before lifting the new one back into place.
I was careful not to curse, it angers the vehicle gods:-)

The good news is that I didn't see any sign of water or crap in the small sample of fuel I recovered from the filter.

Now the issue is getting the bottom plate off the old filter.
Any good ideas or tricks?

I noticed that there is a replacement filter with a built in drain valve and moisture sensor; but is it the same physical size? I got the old one out but even a mm bigger and I'm not sure I could get it back in without removing the vacuum pump or some fuel lines.
The old fuel filter is a motocraft FD-3375 and the replacement is wix 33217.
The wix 33617 has the drain valve and moisture sensor built in.

Any thoughts or advice?

sportyrick 10-27-2021 06:15 PM

My diesel injection re-builder also says ATF is the best injection system cleaner he has used. I would think power steering fluid would be close enough and not have the tell-tail red dye in it.

Booyah45828 10-28-2021 09:41 AM

A lot of people share the same hate like you did. I don't have any tips to make it easier. Any maintenance on a van chassis fights you. Unless it's on the back of the engine, then it's easy as pie.

Those filters should be roughly the same height, and most people ditch the removable bowl style filter for the 1 piece unit because they mangled/warped the bowl trying to get it off.

Plus, the 1 piece unit offers 1 less leak point, but when they're tightened correctly, I've never had the bowl style leak so \_(ツ)_/

alpinekid 10-28-2021 12:44 PM

thanks, I knew I was going to hate it when I got it, i wanted the shortest bus on a truck chassis with the engine sticking out in front but this van/bus showed up only 5 miles from me so I jumped on it to save the problem of buying one 1,000 miles away.
Since I don't have any evidence of crap in the tank, I was going to put a cheap filter in and then take it out after a bit and look, I'm going to put a good filter in and call it a day.

Johnthebusboy 10-31-2021 03:23 AM

If you have rust in your fuel filters you will have rust in your tank. In my case I had to remove the tank, cut it open, remove the rust, and braze it shut. I cannot tell how much fun that?was.

alpinekid 12-06-2021 06:54 PM

just closing the loop
1 Attachment(s)
The fuel filter was as hard to get to as I thought it would be; even after removing the air filter.

I put a oil filter wrench, the strap type, on it and got it loose. Getting it out was another problem. Disconnected some wiring and after pushing and tugging everything around i, it came out, total time about 1-1/2 hours of messing around.
There seems to be two kinds of filters, the new ones have integrated the bottom cap with the drain and water sensor port into the filter.
This was good news for two reasons; I was unable to get the bottom cap off the old filter and the new filter with integrated bottom cap is a centimeter shorter. That centimeter made all the difference. It only took about 2 minutes get it back in.

It started right up, after about 30 second of cranking, over about 1/2 hr. I didn't want to burn up my new starter.
The ATF trick worked; it solved the fast idle problem.
Everything is running fine. Never was able to get the siphon hose into the fuel tank; but my siphon setup work great in getting the fuel out of the filter before I turned in every which way to get it out.

Thanks for all your help:Thanx:

I'm now researching tires. It has 225/75R16 load range E on it right now. Has anyone tried taller tires. I could use all the ground clearance I can get.

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