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Following on from my other thread re the petrol tank, I have had a poke around and the tank in general appears very solid - and I did give it a thorough poke about to be sure.

There is one hole at the bottom of the tank that was pin head size that I have enlarged to a few mm across, then I have used some petrol tank repair stuff and all appears well. However, I have put about a gallon of fuel in the tank (no leaks hurray) and have been churning the starter over for 5 or 10 minutes and I just cannot get petrol through to the engine. I have removed the pipe to the carbs and to the tank side of the petrol pump and both are bone dry.

Anyone any bright ideas what the problem could be and solutions?

Thank you.



1980 persian aqua DHC

Andy, it is possible that one gallon is not enough in the tank, for
the pump to pick up. Get a length of hose, about 3 ft long, & fit it
over the pipe comming from the tank, near the pump.

A qiuck suck should tell you if the petrol is deep enough to pick up.

If it is very hard to suck, you could have a blockage. If so, try
blowing back to the tank, to see if you can clear it. One of these
is your most likely problem.

Did you notice if there was an after market, inline filter fitted
back there, while you were working on the tank? Some fools fit them
back there to keep them out of sight. Out of sight, & out of mind,
they are easy to fill up with dirt, & cut the fuel supply.

Do you have one at the front, causing the same problem?

When you get pin holes in the tank, they are normally from the tank
rusting on the inside. When this occures there is a lot of rust silt
in the tank. Pouring a gallon into a dry tank would stir this up, &
mixing with just a gallon would be likely to cause blockages.

If your pump was dry for a few days, just a a little silt, in the
valves would make it hard to prime. Putting a hose from the pump
into a container of fuel, right beside it would make it easier to
prime, & it should then pump OK after that. It would also fill your
carbs float chambers, so the car would run.

Hasbeen

Thanks Hasbeen, I thought a gallon would be enough. I will get another gallon to be safe, and try sucking it through. Thanks for the ideas.


1980 persian aqua DHC

Hi Andy,

Mine started with a single pin hole but several others followed soon afterwards, all around the bottom front corners.

Once I'd decided to replace the tank I took a pointed hammer and tapped very gently around it. I made 6 thumb sized holes where the metal was weaker than a wafer thin mint.

Prior to my tank replacement I was replacing the in line fuel filter every six months before it clogged up with fine red rust.

Adam



TR7 V8 DHC Jaguar Solent Blue. 9.35cr Range Rover V8, Holley 390cfm, JWR Dual Port, 214 Cam, Lumention, Tubular Manifolds, Single Pipe Exh, 3.08 Rear, 200lb Spax & Solid Bushes, Anti- Dive, Granada Vented Discs & Calipers, Braided Hoses, Green Stuff, 4 Speed Rear Cylinders, Uprated Master Cylinder & Servo, AllyCat 5 Spokes. No Door Stickers. Mine since July 1986, V8 from 1991

One gallon is nowhere near enough. I know, I've been there!

If doubts persist connect the petrol pump directly to a jerry can of fuel.

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Thanks all, up and running now with the aid of a couple of gallons more of fuel and sucking it through before reconnecting the pipe to the petrol pump.
Tasted lovely.


1980 persian aqua DHC

Andy,

If the tank has rusted enough to put a pin-hole in the tank, there will be enough horrible silt rolling around to clog filters up. Its little known that there is actually a filter inside the tank - its a fine gauze mesh on the end of the pick up on the sender unit. What happened with mine is that over time its gets clogged and silted up leading to unreliability.

If one hole has appeared you can bet theres another one coming soon, and another and another...... [:D]

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Thanks for cheering me up Wayne![:D]


1980 persian aqua DHC

HAHAHAHAHA!!![:D]

Sorry Andy, didnt want to sound that morbid about it!

I tried everything to make it last a little longer but in the end - had to bite the bullet.

Job wasn't as bad as I thought it was going to be though to be honest and once I had painted all under there I was chuffed Id done it myself [:)]

<b>FOR SALE!!!!Purple 2.0 Litre DHC Grinnall</b>
Red 4.0 Litre V8 DHC Grinnall (with huuuuuge arches...!)

Andy, for a short term repair, to get a little time before
replacing, or repairing your tank, use a blind alloy rivet.

I have found that 3/16" is suitable for rust holes, although I did
once use a 5/16" blind rivet to repair a tank damaged by a stone off
the road. That "repair" lasted over 5 years, to my knowledge.

You have to drain the tank, drill through the pin hole with correct
size drill, then install the rivet in the usual way.

A fully threaded self tapping screw, [note fully threaded, right to
the head], of a suitable size, screwed into a pin hole, will usually
hold for a few days, or even weeks, to at least get you home.

As Wayne says, the tanks are extensively rusted, inside, before the
first pin hole appears, so although the patch may hold, don't expect
too long before the next one appears.

I have repaired a couple of tanks, as the locally fabricated tank
must be made of gold to justify the price, & airfreighting one from
the UK was about the same price.

I found it is only a strip, less than 3" wide, across the width of
the tank, at the very front of the bottom, [lowest point], that
rusts. This is easy to replace. I believe that in other places with
more corrosive roads, [salt], that the seams go, making repair
impractical.

Hasbeen