All, I've been trying to wake up a 78 XJ12L. I'm now at the fuel tanks and the car has sat since 1986.

The fuel tanks smell of varnish. I'd like to clean them out but I don't want to go through the hell of removing them. I was thinking of draining the tank, then filling the with a couple of gallons of fresh gas mixed with a couple of cans of Berryman's and letting it soak for a couple of weeks before draining it.

They stink of varnish so I know that they will need cleaning. I don't want to go through the hell of removing them so I was thinking of draining the tanks, then filling the with a couple of gallons of fresh gas mixed with a couple of cans of Berryman's and letting it soak for a couple of weeks before draining.

I know that it's not the same as having the fuel tanks boiled taken out and boiled but I don’t have the budget right now.

I also plan on putting fuel filters before and after the fuel pump in order to trap any nastiness before it hits the filter under the hood.

What are your thoughts?

 

Ok, you don't want to take the tanks out, and I sympathise having taken them out in the late 80s on a Series 3 !!

I would suggest flushing through with something not quite as inflammable as petrol (gas), but which is miscible with petrol, maybe cellulose thinners as this will definitely dissolve any varnish because I have used it to clean carburettors.

Drain tank, put the drain plug back, omitting the gauze filter, pour in your cleaner, agitate with something via the filler tube, ( a very long brush with a wire handle, maybe a shotgun barrel cleaner, then drain. Do this several times plus agitate, then put in some petrol, drain off and dispose, then petrol for use. The gauze filter will pick up any solid stuff that may wash down after you have started to use the car, so you may need to drain down again shortly after starting to use the car. Be cautious as petrol vapour is heavier than air and will drift along the ground and accumulate in holes/drains/inspection pits. Have a fire extinguisher handy (or two )

And NO SMOKING whilst you are doing all this !!

 

Thanks for the response, cellulose thinner is not a commonly used term in the US (as they outlawed cellulose paint about 40 years ago) but I'm assuming lacquer thinner will have the same result?

I thought about it earlier but was concerned that it will eat rubber or plastic items that may be in the tank. Also, will it mix with gas (petrol). Per usual, no matter how much you drain, a little will always mix in.

 

Whatever you use will always leave a little bit in the tank/s.

Using a solvent type product like thinners etc will evaporate usually overnight, and the less to evaporate the quicker that will happen.

I had to wake up an XJ12C from an 8 year sleep with FULL tanks of "fuel", a few years back, and there was NO WAY I was taking those tanks out, my sense of humour is way gone in that area. I used fresh petrol, VERY BLOODY CAREFULLY, and a nylon brush on a stick, and 3 days later I was happy enough. I drained it into a large oil drain pan and killed all the neighbours weeds. The old fuel was basically rusty water, YUCK. I installed 2 X 1/2" Wix filters in the supply lines to catch whatever, and left the EFI filter as designed, as too much filtering may cause other issues, and I did not want too many surprises. I told him to keep the tanks FULL, and 4 years later the Wix have been eliminated, and the engine never rmissed a beat, ever.

The fuel pump was serious TOAST, so a new obviously fitted.

 

Good morning, Give the Berryman's a "sniff test". You will notice the odor of lacquer thinner as this must be its main ingredient. I've used lacquer thinner mixed with gasoline to clean fuel systems (both carbed and injected) many many times with positive results .A running, gasoline fueled engine can tolerate A LOT of lacquer thinner and I've never experienced any damage CAUSED BY USING THIS METHOD.It has been my experience that water and/or alcohol adulterated fuel left for extended periods of time is the most common cause of fuel system component damage. An added benefit to using lacquer thinner is that it helps to keep catalytic converters clean. The advise given by Fraser Mitchell in his earlier post is "spot on". Cheers, Andy

 

I just did this to my car after sitting for 15 years, I just drained them and removed the sender. Through the sender hole I did a inspection to see how much rust here was. They weren't to bad so I used a garden hose with just water and a high pressure nozzle, there I took a tool that I use to clean out my black tank on my RV. It is 1/2 in of PVC that hooks up to my hose at the end of the hose are four small holes that spray out at 90 degrees from the pipe. With the hole being small it gives great pressure. After that they looked great. I used a garden leaf blower to dry them out an let them sit for a few hours before I sealed them back up. I got the car running and took it to the gas station a filled them up. So fare so good.

 

I put water in the gas tank once in a Mercedes Benz 500SLC. It never ran right afterwards I'm glad that worked out for you but i'm never doing that again.

 

I made sure that the tanks were good and dry before putting gas in the car and then purged the line with fresh gas buy unhooking the gas line just before the filter and ran it until there was clean gas running out. Also the high persure of the water hose get all the loose stuff out I feel better than using harsh chemicals.

 

Well , i took the drain plug off and nothing came out so I dumped 5 gallons of lacquer thinner in there which I will let sit for a few days.

This stuff is expensive so I hope I could reuse it on the other side.

When I opened the fuel lid, it was full of this yellow dust. Any idea what it is?

 

Have you taken out the really big plug, or just the small drain plug ? If it was me I would take out the big plug, as this has the gauze filter on it. and you need to clear this, from what you say about nothing coming out the drain.

 

I pulled the fuel tank stainer out and this is what I found. There is still plenty more inside.

It looks like I may need another tank or two.

 

Not being a defeatist by nature, but I reckon you are buggered here.

That is a REAL SAD pile of "stuff", and the integrity of the tanks must be very suspect, so replacements will be less grief than persisting with these, in the long term.

The tanks are a mongrel to get out, but constant engine/pumps/injectors failing from that stuff will be WORSE.

 

Thanks, I think right now I will continue to clean the fuel system up front and get the engine running. If I can get it running well out of a gerry can, then I will spring for new tanks. Else there is no sense in spending the money on new tanks if the engine is bad.

 

While I realize this is an old post, I too must do the same.
I own a S1 however so removing the tanks is easier, and something (a s perfectionsit) I really must do as i would like to rust coat those inner panels and area once removed, as well as restore the tanks properly...

THAT said, Mr Grant above was spot on as usual (from all I have read on this forum) ..those are too far gone.

HOWEVER, as another suggestion, go to WalMart and get gallons of distilled white vinegar and fill it up, let it soak a week..

Non flammable, non toxic, and cheaper than gasoline.

On another note, I suggest the same for flushing the radiator/cooling system...and no it is not harmful to aluminum.
FWIW

 

..and no I am not a perfectionist when it comes to typing!

 

I had a better idea and sold the car. I do have a 75 XJ12C that was converted to propane before I bought it. I converted back which required new fuel tanks. As far as I'm concerned that's the way to go.