Fuel Tank

[Paul Evans]

Hi, I'm new to the forum with a question!

My TR7 had been sitting around for a number of years before I got it. I started with giving it a full service, changing to electronic ignition, replacing the suspension and I'm partway through replacing the bushes, and it's been given a paintjob.

 

I took it out for a run a couple of weekends ago and it stalled out - it would sort of restart but only with the throttle fully open and then die out after a few seconds. Towed it back home and then it started without a problem. I opened up the float chamber and noticed large amounts of "silt" in the bottom of the fuel resevior, which I cleaned out and then fitted an in-line filter in-front of the fuel pump. It's been running fine in the workshop and when I drive it around the driveway but I noticed that the filter had accumulated more "silt" so it's been cleaned and the carbs again.

 

I strongly suspect that the fuel tank has rusted and it's particles of rust coming through the fuel line, I'm suspecting that as it's standing and being run that the sediment is staying at the bottom of the tank buit when I actually take it out, the sediment is getting "swirled" about - resulting in getting the fuel line blocked?

 

Anyway the result to this long story is that I need to clean the tank - is this possible in-situ, because it looks like a difficult job to remove the tank from the car, if I do remove it is it even work trying to clean or try to get a new one?

 

BTW the car is in Sweden - and I need to do it's import MOT soon!

 

Attached is a picture after the new paint job!

[Hasbeen]

Paul, I had the same problem with a 7 that had sat for a few years.

 

I jacked the car up about 2 Ft high, at the back, removed the fuel sender, & then siphoned the fuel & muck out, using a 1/2" hose.

 

I strained 5 liters of the petrol, & repeated the process 3 more times, & reassembled the thing, added a new filter, & clean petrol.

 

After a month, & about 1000 Km the filter required replacement, then at 6 weeks the tank pin holed, with rust, from the inside.

 

I drilled a 1/4" hole through the pin hole, & inserted a blind pop rivet, which sealed perfectly.

 

A month later 2 more pin holes appeared.

 

I bit the bullet, & removed the tank.

 

On inspection, I found it was only the front 2" of the bottom, which was rusty. As it was a big deal to get a new tank in Australia, I cut the rusty strip out, & welded in a new bit. The tank was then treated with POR15, internally, & has been back in service, successfully, for over 4 years.

 

I have since done another tank, which had the same problem. I did think of just giving this tank the POR15 treatment, without the repair, but decided that its too big a deal, to R & R the tank, to do a rough repair, that may not work.

 

By all means, try cleaning the tank, but I believe, if there is much silt, the internal rust is close to pin holling the tank.

[kevp]

Hi Paul,

I,ve just had to replace my fuel tank for the same reasons. It started with carb problems as you described and i also fitted an inline filter. But soon after the tank started weeping from a small hole on the front lower edge which on inspection turned into a large hole. I ended up with my finger in the hole shouting for my lad to get some buckets as i had 3/4 of a tank of fuel.

The point being, if you want peace of mind its better to replace with a new tank. Not the easiest job in the world but quite manageable. The Haynes manual has a good section on how to complete the job.

I hope this is of help

Kev

[anthonyt]

Taking the tank out isnt that big a job but it is tedious getting it back in, i took the tank out and had it professionally cleaned and then sealed with an epoxy, no probelms since, whilst it was out i had a swirl pot added to the bottom for track days but that isnt important for around the streets.