Tank varnish

[Helirich]

I thought I would give my experince on fuel system and some thoughts.

I pulled my pump and it and the tank were full of crud. I cleaned the tank useing fresh gas. This works, but not very good. The instructions with the new pump said to use acidtone. I can tell you, it works MUCH better! I installed the new pump, but before hooking it to the fuel lines I wanted to clean them.

I removed the filter at the back of the car and ran about a 1/2 gallon of acidtone throughfrom the front. I just used a funnel in front and a bucket in back to catch it. I followed this with a gallon of fresh gas. (I didn't want acid residue in the line) There was very little crud, if any, in the line. I removed the line going from the filter to the injection pump and cleaned that also. I noticed that line was bone dry. I also noticed the filter would only dump fuel out of the inlet end. (Nothing out of the outlet) So I thought I would investigate.

I cut the filter at the outlet end.

IMG_0455.jpg

I'm having a problem put pics on here. If this works, you can see the outlet end of the filter is bone dry. You can also see the fine screen on the filter. (All dry)

I pulled the screen out and found rolled up paper. This paper was soaking wet with gas.

Attachment 65599

Not sure if this paper is swelled from water/gas, but it was tight in the canister. I pulled it all out and it didn't seem to have any crud in it.

While the tank was full of junk and the pickup sock was basically disintegrated, I don't think anything made it past the filter. So I don't believe that trying to start a long sitting car is dangerous to your injection system. Now, let me be clear, there very well may be varnish in my injection system from gas that was sitting there as long as the tank gas, but it didn't come from the tank.

In any case, I have electrical issues, so I can't start the engine right now. But I'll let you know if the fuel distributor needs rebuilt once I get that sorted.

[Riley88]

Good luck man, keep this thread updated!

[dmcman73]

I thought I would give my experince on fuel system and some thoughts.

I pulled my pump and it and the tank were full of crud. I cleaned the tank useing fresh gas. This works, but not very good. The instructions with the new pump said to use acidtone. I can tell you, it works MUCH better! I installed the new pump, but before hooking it to the fuel lines I wanted to clean them.

I removed the filter at the back of the car and ran about a 1/2 gallon of acidtone throughfrom the front. I just used a funnel in front and a bucket in back to catch it. I followed this with a gallon of fresh gas. (I didn't want acid residue in the line) There was very little crud, if any, in the line. I removed the line going from the filter to the injection pump and cleaned that also. I noticed that line was bone dry. I also noticed the filter would only dump fuel out of the inlet end. (Nothing out of the outlet) So I thought I would investigate.

I cut the filter at the outlet end.

IMG_0455.jpg

I'm having a problem put pics on here. If this works, you can see the outlet end of the filter is bone dry. You can also see the fine screen on the filter. (All dry)

I pulled the screen out and found rolled up paper. This paper was soaking wet with gas.

Attachment 65599

Not sure if this paper is swelled from water/gas, but it was tight in the canister. I pulled it all out and it didn't seem to have any crud in it.

While the tank was full of junk and the pickup sock was basically disintegrated, I don't think anything made it past the filter. So I don't believe that trying to start a long sitting car is dangerous to your injection system. Now, let me be clear, there very well may be varnish in my injection system from gas that was sitting there as long as the tank gas, but it didn't come from the tank.

In any case, I have electrical issues, so I can't start the engine right now. But I'll let you know if the fuel distributor needs rebuilt once I get that sorted.

I did the same exact thing many months ago and posted that procedure on one of the Facebook Delorean groups. As long as you do not run acetone through any of the components like the fuel distributor, it will clean the steel lines right out. Flushing it with gas afterwards ensures that the acetone is properly flushed out.

You can use a cheap hand operated fuel pump to push the acetone through the steel lines, it works better as the pressure from it will loosen any crud in there better.

[Helirich]

I did the same exact thing many months ago and posted that procedure on one of the Facebook Delorean groups. As long as you do not run acetone through any of the components like the fuel distributor, it will clean the steel lines right out. Flushing it with gas afterwards ensures that the acetone is properly flushed out.

You can use a cheap hand operated fuel pump to push the acetone through the steel lines, it works better as the pressure from it will loosen any crud in there better.

So did you have to rebuild the fuel distributor?

[cdrusn]

You didn't say how long it had been since you ran the car and filled it with fresh gas. I recently was changing fuel hoses as maintenance and it had been several years since I ran through the gas. So before changing the hose I used the fuel pump to put the discharge into a gas can. It was green and smelled bad but not varnish. Then I put
fresh gas and stabil and ran the car for awhile. I hope to find a gas station that sells gas without ethanol to fill up this summer.

[Rich]

For the fuel varnish recovery questions -
See this detailed How-To for dealing with a DeLorean's fuel system after the car has been dormant too long:

dmctalk.org....How-To-Clean-out-fuel-tank-and-flush-fuel-system-BEFORE-you-try-to-start-the-car

It covers lots of tips in the Tank Varnish thread plus lots more.

Over 68,000 views of this 2011 post! Thanks to Tom Tait for posting it.

[Helirich]

For the fuel varnish recovery questions -
See this detailed How-To for dealing with a DeLorean's fuel system after the car has been dormant too long:

dmctalk.org....How-To-Clean-out-fuel-tank-and-flush-fuel-system-BEFORE-you-try-to-start-the-car

It covers lots of tips in the Tank Varnish thread plus lots more.

Over 68,000 views of this 2011 post! Thanks to Tom Tait for posting it.

Yea, I read that one. I disagree with a couple things.

1. He perpetuates the myth that the tank crud will be pumped through the filter to the fuel distributor.

2. I don't like the idea of pumping acid through an old filter even if he bypasses the distributor. He does say to change the filter later, but why send filter material through the lines? If the filter is not distroyed by the acid, it might be OK, but has this been tested? In my case, I don't think anything was going through the filter unless it "ate" it's way through.

[David T]

It's not acid, it is Acetone. It is a solvent, it is not an acid. It does not have to be neutralized, it gets diluted. Either method is OK.

[Helirich]

It's not acid, it is Acetone. It is a solvent, it is not an acid. It does not have to be neutralized, it gets diluted. Either method is OK.

Ha-ha, I guess I never read the can. So do you suppose I could run it straight as a fuel for a few minutes to clean out the fuel distributor? I wonder how it would run the engine as compared to gas? I wonder if "seafoam" is made of it?

[David T]

Don't try running on Acetone. Too flammable. Once you can get the motor running and the car driving, fill up the tank and pour in a can of Techron fuel system cleaner. Modern fuels have cleaners added so if you use the car regularly they will keep the system clean. If the injectors are not spraying good patterns and/or they are not all opening and closing at near the same pressures, they should all be removed and cleaned and tested. If the injector seals are hard and not sealing well they should be replaced at that time.