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TR4/4A TR4a Fuel Pump

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DavidLayton

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Had a leaking fuel pump which I replaced with a repro from Rimmer Bros. The repro had the priming lever which was not on the one I removed.

Installed the pump. It appears not to work, only running off the prime. I am assuming that the cam and the lever are not making contact. Not sure why this is, it seemed to be a fairly simple connection.

Now one area of difficulty on this is the lack of a fuel shutoff which means that fuel will shoot out the fuel line once it is disconnected from the pump. If I have to detach the fuel pump, how do I deal with this?

Thanks!
 
If you're disconnecting the rubber/composite fuel line from the pump, it's simple. Just always have either a fuel line clamp tool handy (HF sells a barely adequate one), or have a suitable size bolt and hose clamp ready. That's just the situation. You either block or squeeze it off, or you'll have a small mess. The reality is that you'll spill a little fuel no matter how you do it, but it's just a routine. Disconnect the pump/block or plug the fuel line. It will become second nature. I even keep a special hose and bolt piece ready at all times in my parts cabinet.

Now, as for the pump. You're supposed to rotate the crank so the cam lobe for the fuel line has the least protrusion toward the pump lever. That's not critical, but it make fitting the pump easier. Then, make sure the pump lever isn't falling under the camshaft lobe or otherwise improperly fitted. When you fit the pump on the block bolts you'll feel some pressure, and you'll need to push the pump toward the block (depressing the pump lever) as you tighten the nuts.

If that pump isn't working after that, I'd be surprised. I even wonder how you're determining it's not working? Do you have a filter bowl? Are your floats set properly. I've had a dozen pumps over the years. None failed to work. Culprits can be at the carbs or even in the gas tank. Be sure nothing back there is plugging your flow. I've had mine plugged twice, once by a prankster who put a 2 X 4 in my tank, and another time by debris from improper tank restoration coating material.

Let us know what you find.
 
I always try to fit a new pump to the block by holding the pump so that the lever that fits into the block is pointed up. This should allow the lever to lay on top of the cam once the pump is completely installed.
I use a motorcycle fuel shutoff on the 5/16" line before the fuel pump. I will get the numbers and add to this post.
Charley
P.s. a unit like Motion Pro 12-0036 5/16" as found on Amazon.
 
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You should be able to feel the cam or see it with a mirror and flash light. Plus you can operate the pump by hand to help see how the stuff should go.

steve
 
My experience with AM fuel pumps is so bad, I only use re-built units I have personally
done. They are pretty simple to do with the caveat of needing the notch on the plunger
squared with a small file and then test fitted.
The real trick is getting the bugger off/on.
Mad dog
 
After I thought about it, I am not sure they will bolt up and fit in wrong. However, every time I replace one, I am thinking did I put that in correctly. Either way sounds like the pump needs to come out. Never sent stuff back to Rimmer bro. Maybe get one from Moss or TRF. Fuel pumps are a pain to get in. I have found a ÂĽ drive socket with the correct extension fits in that tight spot nice.

Steve
 
True enough Mike ,if you don't mind spending extra ,get the TRF pump. But they also sell a kit for the old pump
which old skinflints like me prefer.....so I can splurge on other goodies.(and not be caught out)
Somebody tell me why an old AC fuel pump ,once made under license in the UK, is now made in Italy.
Mad dog
 
mctriumph said:
True enough Mike ,if you don't mind spending extra ,get the TRF pump. But they also sell a kit for the old pump
which old skinflints like me prefer.....so I can splurge on other goodies.(and not be caught out)
Somebody tell me why an old AC fuel pump ,once made under license in the UK, is now made in Italy.
Mad dog
Click to expand...
I’m with you on the skinflint! Unfortunately the inlet threads on my original pump (an aftermarket already) were stripped beyond repair. Having heard bad stories about replacements, I paid my dues for quality.
 
The bits can be mixed and matched, BUT having the OE body and arm assy is the whole point.
All the failures I have encountered are due to terrible quality of this bit on the AM pumps.
The arm and the way it is made up from bits of pressed steel plates is the dead giveaway.
Mad dog
 
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