Fuel Line Questions

[PatGalvin]

Hi Guys

Well, I've finished block sanding the TR3 - I've been at it since before Thanksgiving - is a huge effort, to say the least. Photos to follow on that.
I need to install a new fuel line before I put the body back on the frame and am doing some planning. I have a replacement tank from Jorge in San Diego that I'll be installing. I have the old fuel line and fittings as a go-by. My car was missing the shut off valve near the fuel pump so I do not have that device.

Two questions - for those that have replaced your fuel line - did you purchase a precut line with appropriate fittings from one of our esteemed suppliers, or did you reuse fittings and just purchase 5/16th tube from FLAPs? Second, what options do I have for replacing the shut off valve up front? I don't need for this car to look original but do think it might make sense to have a shutoff valve at the end of the hard fuel delivery pipe. Has anyone come up with a fuel shutoff modification that has worked well?

Thanks for the tips. Photos of finished sanding and of my garage paint booth to follow in next few weeks.

Pat

 

[Member 10617]

Don't know if this is relevant, but a shut-off valve is a very handy thing to have when you are removing the glass bowl off your mechanical fuel pump to clean the filter or replace the gasket. Unless you have a shut-off valve, gas will flow out by gravity from the gas tank from the input to the gas pump. At least that has been my experience. Perhaps there is another way to prevent this from happening, but I don't know what it would be. Some of the other more experienced folks on this forum might have an answer.

Also, I have found that you need to tie a thick cord around the bottom of the button on the shut-off valve to prevent it from being pushed (closed) accidently or vibrating itself down. To close the valve, take the cord off, push the button down, and the fuel stops flowing. Just something that works for me.

 

[mgedit]

I have the shut off valve in original location, but am considering adding one near the tank too in case I need to drain the tank some time. Ideally I want a shut off with a drain as well. Not sourced anything yet. Any one with ideas? Cheers, Mike

 

[Lukens]

No help here, just want to thank the forum members for all this good stuff I'm learning. Just checked, I have no shut-off valve. Must have been removed by PO.

 

[TR3driver]

Later TR3A/B didn't come with the valve. I assume it was a cost-cutting measure as it does come in very handy when you want to clean the sediment bowl and have the tank nearly full.

Instead of a drain under the car, I find it a lot easier to hook up a spare electric fuel pump to the battery charger. (I have one of the little square Facet pumps that I sometimes carry on long trips in case the original mechanical pump fails. $15 used on eBay)
That way you can empty the fuel directly into something else (like another car) and not worry about overflowing a container small enough to fit under the car. You can either pull off the inlet line to the pump under the hood, or just drop a length of hose into the filler opening.

Ed, the original shutoff valve should have a locating pin and notch, such that you turn the handle to lock it in the "on" position. The seal should provide enough friction to hold it there.

 

[Member 10617]

Randall,

As usual, you are absolutely right about the locating pin and notch. The trouble with my shut-off valve is that it seems rather loose and might easily slip into the closed position. the little cord or string around the valve stem reassures me that it won't move.

I have read that there is no shut-off valve on many of these cars, as you point out. Shouldn't be too difficult to add one. They are readily available from the normal suspects.

Now a question: If a TR3 doesn't have a fuel cut-off valve, how do you keep gas from leaking out all over the place when you remove the sediment bowl to clean it, the filter, and replace the gasket? This gasket tends to get flattened out or scored over time and has a tendency to leak, especially if the bowl is over-tightened, or perhaps even if it is not over-tightened. So it has been my experience that it may have to be replaced from time to time.

 

[sp53]

Yes the later tr3 uses the same system as a tr4 with rubber connecting the lengths from the tank to longest run whereas around 58 and earlier they have brass couplings and a shut off. I used my old one for a pattern and bent my own. I would suggest flushing out the new gas tank real good. I bought one from him and I did not and it put about 6 ounces of crud in the carb bowls. The stuff went right by the fuel pump screen. If I would have had a paper, I am sure it would have plugged it the first day.

 

[Don Elliott]

Mike - I tried two different approaches. I drilled and tapped a drain plug and put in a drain valve like on the side of the block or at the bottom of the radiator.

All that did was vibrate till it was fully open and I ran out of gas.

The second apprach was to get a stainless steel ball valve and some 1/4" NPT pipe and elbows etc. to lead down to the manual drain valve.

On bumps, only about 20 miles after installing this the new drain assembly, it was hitting the top of the differential or something else near there and broke one of the short lengths of steel pipe. I made it home this time before running out of gas.

I wouldn't do it again. Nor should you.

 

[glemon]

I don't know about the TR3s, but my old 4A and current 250 have a rubber section in the line just after it comes out of the tank and I think maybe after it comes up from the frame towards the pump, a clamp (I use a needle nose vice grips) on the rubber line works very well as a shut off valve when needed, just squeeze tight enough to stop the flow, not enough to cause too much stress on the rubber.

 

[CJD]

My shutoff on the TR3 is to pinch the rubber hose with a vise grip. Much simpler than the shutoff valve. Even simpler would be to park facing uphill.

From what I have read, the original shutoff valve was discontinued because it tended to leak. Guess I'll find out with the TR2, as it came with the valve...

 

[mgedit]

Mike - I tried two different approaches. I drilled and tapped a drain plug and put in a drain valve like on the side of the block or at the bottom of the radiator.

All that did was vibrate till it was fully open and I ran out of gas.

The second apprach was to get a stainless steel ball valve and some 1/4" NPT pipe and elbows etc. to lead down to the manual drain valve.

On bumps, only about 20 miles after installing this the new drain assembly, it was hitting the top of the differential or something else near there and broke one of the short lengths of steel pipe. I made it home this time before running out of gas.

I wouldn't do it again. Nor should you.

Thanks Don ... Sounds like good advice! Cheers, Mike

 

[Member 10617]

John,

My shut-off valve has never leaked, but -- as I wrote earlier -- it is very loose and appears that it can easily vibrate or otherwise fall into the closed position. Perhaps not. In any case, a little string tied on the post under the button keeps it up and open.

In addition, it is so sentive that it can be pushed down very easily, by accident.

I have a new shut-off valve on my shelf, but haven't seen the need yet to replace the old one.


As for draining the gas tank, I prefer to use a hand pump before resorting to opening the plug at the bottom of the tank. I pump the gas into a gas container, and then empty the container into another vehicle. My experience is that the plug under the gas tank, even with a new, good washer (gasket), seems to leak easily. Presently it is not leaking, so I am leaving it alone unless otherwise needed.

 

[TR3driver]

Mike - I tried two different approaches. I drilled and tapped a drain plug and put in a drain valve like on the side of the block or at the bottom of the radiator.

All that did was vibrate till it was fully open and I ran out of gas.

The second apprach was to get a stainless steel ball valve and some 1/4" NPT pipe and elbows etc. to lead down to the manual drain valve.

On bumps, only about 20 miles after installing this the new drain assembly, it was hitting the top of the differential or something else near there and broke one of the short lengths of steel pipe. I made it home this time before running out of gas.

I wouldn't say don't do it, but I would say there are some important lessons there:

1) Be sure you use a valve rated for use with gasoline. Water valves are generally a poor choice, especially with ethanol in the fuel.

2) Unless the valve is extremely light, it must be suitably supported. Don't just let it hang on the line.

3) Unless it is mounted directly to the tank, be sure to allow for relative movement between the tank and valve. The whole car flexes slightly, even under moderate driving on a smooth road; let alone during spirited driving or on a rough road.

4) Rigid water pipe (the kind that is threaded NPT) is generally a poor choice for anything on a car. Except maybe spacers and even then it's best to cut off the threaded portion.

5) For anything near the suspension, be sure to allow for maximum movement plus an inch or so. All the joints and stops compress to some extent on bumps.


I solved the leak on my original shutoff valve long ago, by cutting a short length of nitrile fuel line to replace the cork seal. It took several tries to get the adjustment just right (the slotted screw and locknut on the handle), to get a balance of no leaks and still able to move the valve; but I did find it. That was around 1985 and in all this time, I've only adjusted it once because I saw a bit of weeping. (The "new" TR3 came with some kind of aftermarket valve that had turned to goo inside, so I installed the valve from the wrecked TR3A.)

 

[bobhustead]

I bent a piece of metal tube to fit from the tank forward and insulated it so as to avoid exposing rubber to the heat of the muffler, which will be real close.
Bob

 

[SteveBones]

I needed to "rebuild" my fuel system. I also used a vise grip as well at both locations (close to the tank & fuel pump) as I had to trouble shoot a fuel starvation issue and was not sure of the cause or location. This was easy and the way I would go in the future.

Regarding the line replacement. I reused the line from the tank in addition to reusing the line that runs under the floor boards so I can not help on this. I did need to replace or purchase the fuel lines that attach to both sides of the mechanical fuel pump. I tried going with what was available at the local Ace Hardware and car parts stores in town. I ended up purchasing from Moss because they included the correct fittings that I could not locate elsewhere. The issue I had is that Moss only sells the "longer" fuel line piece that goes from the fuel pump to the carbs. I ended up having to purchase 2 of these longer pieces since I needed the same fitting for the other side. The issue with this was really the cost, but it ended up working as desired.

So I would say for at least this section of the fuel line, if you can find the correct fittings (or still better yet have the originals) then purchasing just the fuel line its self would make sense, and cut to length.

My shutoff on the TR3 is to pinch the rubber hose with a vise grip. Much simpler than the shutoff valve. Even simpler would be to park facing uphill.

From what I have read, the original shutoff valve was discontinued because it tended to leak. Guess I'll find out with the TR2, as it came with the valve...

 

[sp53]

You reminded me of something that happened a while back John. Anyways, my shut off had been fine for many years then it started leaking badly, and I realized that the older system is all hard plumbed in with metal and how was I going to fix this thing with a full tank of gas without gas going everywhere. What I finally did was pull the guts out of the shut off and let the gas flow and jam a rubber plug into the hole until I could come up with a replacement. Fortunately I remembered, I had an old shut off and I used the guts out of that then just did a messy switch around with gas flowing everywhere. I used to carry that plug with me in the glove box, but I do not remember seeing it. I think I will look for it.

 

[Member 10617]

Not exactly relevant, but related to this thread:

When I purchased my TR3, the engine compartment smelled of fuel. There was weeping from the carbs, float chambers, and elsewhere, etc., etc. Friends who had these cars or who had had these cars said, "Oh, that's just normal for these cars... That's just The Triumph Smell... These cars are just going to leak...Don't worry about it" and on and on.


Seemed to me that it was a BAD idea to have fuel weeping down on a hot manifold, no matter what reputation these cars had. So I kept at it for over a year until I tracked down and eliminated every leak/weep. Perhaps there was little danger of fire, but better safe than sorry.

My message to new owners: When dealing with the fuel system on these cars, don't accept the idea that "they just leak" (fuel). do your best to stop the leaks/weeps. It can be done. It's a safety issue if not just a cosmetic/smell issue.

Now I'll step down from my soap box...

However, as far as OIL LEAKS are concerned.... it's another story. I believe it is true that these cars are just going to leak/weep.. Much can be done to minimize the leaking, but don't count on stopping it altogether.

 

[TR3driver]

how was I going to fix this thing with a full tank of gas without gas going everywhere.

Glue a piece of string to a big marble, drop it in the tank and coax it on top of the outlet. Won't stop all the fuel going through, but will greatly reduce it. On an earlier TR2/3/A with the outlet in the center, you could probably even use a sharpened stick.

Another option is to use the spare electric fuel pump to move it to another car, after filling the lawnmower can (so you can have enough to get to a gas station afterwards). That's what I did to repair a leak in the tank.

 

[sp53]

Right on Randall, I like the stick in the center that wouldwork.