• Hey Guest!
    British Car Forum has been supporting enthusiasts for over 25 years by providing a great place to share our love for British cars. You can support our efforts by upgrading your membership for less than the dues of most car clubs. There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Upgraded members don't see this banner, nor will you see the Google ads that appear on the site.)
Tips
Tips

fuel pump rebuid kit

Share this page

A

Adrio

Jedi Knight
Country flag
Offline
Has anyone had any problems with the rebuild kits for the original AC pumps (the ones on TR2/3/4 and maybe other engines) that Moss sells. I bought two of them and they are made by BM Parts. Both have had the diaphragm fail within one hour of service. It seems the diaphragm is becoming porous. It seems like the red rubber on the surface of the diaphragm is perishing right where the edge of the metal disk in the middle of the diaphragm is.

Does anyone have experience or comments on this.

Adrio
 
Sounds like what the original rebuild kits did when exposed to our 'reformulated' gasoline in California. Burlen had to change the formulation for the diaphragms.

You might try buying from TRF instead. They carry genuine kits with nitrile rubber on the diaphragms.
 
Adrio, I'm curious. Is there any indication of manufacturer on the kit you got? I haven't seen red rubber fuel pump diaphragms in some time; actually, I thought when I saw your message that maybe these were some old replacement kits from...wherever. And I say that because I was helping a friend resurrect a late 1930s Austin 10 a couple years back. He had one of those red-rubber-diaphragm kits; must have been ancient, but it worked. (I think he also had an NOS AC kit, but I don't recall which was which in terms of diaphragm color/composition.)
 
Andrew,

I bought two kits from Moss (via a distributor) last winter about Christmas time. The box they came in said "BM PARTS" and that was the only indication of a manufacturer I could find. Both kits acted the same way. Between what Randall said about it hapening in California and Don's warning (on an other thread) about gas from PetroCanada, where I had just bought my last fill up, having ethanol I am pretty sure that is the problem.

I have an email into the place I bought them. They say Moss stands behind the product so I will see how we can resolve this.

I too was surprized to see the red diaphragm. All the ones I have used over the years have been black.
 
i got a new pump from bv. it is porous and when the car sits for a few hours the entire pump is damp. it's going in the trash, will watch here to see what you come up with.
 
Andrew Mace said:
Adrio, I'm curious. Is there any indication of manufacturer on the kit you got? I haven't seen red rubber fuel pump diaphragms in some time;
Click to expand...

Andy, I got a rebuild kit from Canley Classics a few weeks ago, and it has a red rubberish fuel pump diaphragm. No indication of brand name on the packaging.
 
As I understand it, US law now requires at least 10% ethanol in all gasoline sold for road use.
 
There has been talk about the ethanol potential problems in the past. Best to stear clear as long as possible in the LBC's.
Does anyone stock the real AC fuel pump rebuild kits for TR6's anymore? The real AC brand that is.
 
The last kit I got from TRF said it was genuine AC; and stood up to California gasoline just fine. Unlike an older genuine AC kit I had on hand, that started leaking in a matter of days.
 
I am ready to put trf kit in original AC pump. Probably dumb question but before I get plier and yank them out and regret it there are two diaphrams one in, one out, in the cover which look pressed in. Trick to this? Now that engine is secure with mounts getting brave to gas up for another test run.
 
thanks if I think i can get the carb valve to smooth out which i am closer on i may go for a ride yet this weekend. I am pretty sure thats what this is all about. when i've had the time this summmer seems like i've been on my back on cardboard. there is a tv commercial which makes this sound better than it does right now.
 
how do they come out?. there are 3 pressed in fittings in all, the bottom looks like the metal fitting is resused and the rubber under is in the kit. the top two come out and are replaced. all three are tight and don't want to come out? brute force?
 
Earlier pumps had a clamp and screw to hold the inlet/outlet valves in place, but later (and replacement) pumps had them staked into place. You might be able to find the staked places and grind them away, but it's basically a brute force operation to remove the valves. Then you need to find new places to stake the new valves. Be sure you've got them installed the right way around first !

My suggestion is, unless you know the valves are defective, just leave them alone. They don't usually fail, since they don't flex constantly as the diaphragm does; and if they do turn out to be a problem, it's not difficult to replace them later.

Not sure about the seal in the bottom, but ISTR the metal retainer is supposed to be pried out and reused. The TR3 book also says to leave this seal alone unless it's known to be defective.
 
My suggestion is, unless you know the valves are defective, just leave them alone.
I like your suggestion but car is original owner this probably never has been touched now is the time. You say not difficult but i can't get them out. inclined to get new pump.
 
I meant it's not difficult to get back to the valves, not that they were easy to get out.

The fuel pump valves in my 59 TR3A might well be original, I've never deliberately changed them in the over 20 years I've owned the car. And they aren't even staked in /bcforum/images/%%GRAEMLIN_URL%%/smile.gif Long experience has convinced me "If it ain't broke, don't fix it" ... there's always plenty of things that are broke.

Be suspicious of any new pump you buy; like so many other things, some of the aftermarket pumps are noticeably poorer quality than the originals. In particular, some of the ones without priming levers have the pivot pin only held by staking, and it has a tendency to work loose over time. I've heard of entire engines being ruined, because that pin fell out and let the pump lever fall into the cylinder block, where it jammed and broke the camshaft.
 
ouch. simple proactive fix gone bad. i am trying to go around the outside of car with that approach to see major needs. can't imagine diaphrams as original don't need to be replaced after 40 years, working or not. nothing to lose so either i will beat the crap out of the current valves or toss what is not that much more at at new pump.
 
An update on my original TR4 pump issue. I tried two diaphragms both from a major vendor and they both failed the same way. It was obviously a chemical reaction to the fuel (I suspect the ethanol in the fuel today). Both these were red diaphragms with one layer of material. I now have installed a kit from an other supplier and it has a black diaphragm that has three layers of material (like the maybe original I took out of there). So far so good with this one.

As to the lasting time of an original pump and valves. My TR3 still has the same pump and valves in it and it works fine. After the trouble I had with the "preventive" maintenance I did on the TR4 pump I am not going to touch the TR3 pump.
 
Back
Top