TR2/3/3A TR3 fuel pump rebuild

[SeanTR3]

Hi shadetree mechanics,

I received the rebuild kit for the fuel pump, took the fuel pump off the car and as I compare old and new parts I have some questions.

The new kit comes with several gaskets and valves, but doesn't appear to have the oil seal that resides inside the lower body under the diaphragm spring. Is this seal necessary anymore? I called Moss, but the salesman did not have a part number for it and confimred that the kit does not contain the seal.

One book we have shows the seal as it appears on our car and the other book does not show it at all.

I assume the larger round rubber seals are for the sediment bowl and one of the paper gaskets is for the fuel pump/engine block junction, but I'm not sure about the other gaskets. Maybe they are for other TR models?

I'll try to post some pictures and If anyone knows about the oil seal and gasket questions, I would appreciate the help.

Thanks.

Sean

https://pg.photos.yahoo.com/ph/sdelthony/album?.dir=/6066&.src=ph&.tok=ph5dA2CBKxcsfGHn

Update, I took apart the canadian pump we had as a spare and it has no oil seal inside of it. I wonder if the oil seal was just a better feature found on the original pump. I guess I can reassemble the old pump without the oil seal. Yes, No?

 

[Geo Hahn]

The oil seal is usually not supplied (TRF may still have it in their rebuild kit). Seems to be unnecessary in my experience.

Yes, a 'square O-ring' for the sediment bowl and a paper gasket for the block (sort of a rounded parallelogram with a slot in it). Not sure why you would have other gaskets.

ISTR one manual wants you to tighten the screws whilst holding the lever & diaphragm in a particular position in its stroke. I have never found that particularly easy or necessary. I just put the diaphragm in with a half-twist and button it up.

 

[Geo Hahn]

Okay, looked at your photos. The gasket on the lower right is the one... the sediment bowl gasket is whichever fits.

Your 3rd pic shows the diaphragm and spring... hopefully you realize that the spring goes on the other end, i.e. it goes over the notched shaft under the diaphragm.

I see you have the old oil seal & retainer with your primer pump -- I would certainly reuse it usless it is truly perished.

Your check valves are held with screws which is good -- some are peened and I have had those fall out. Just be sure you get them in the right way 'round.

 

[SeanTR3]

Thanks Geo Hahn,

I think this kit may be for more than one model and the gaskets cover all the applications.

About the spring, yes, I realize it goes in the other side, I just used it to prop the diaphragm up for the picture. I'd be in for some real trouble if I tried to assemble it as it looks in the photo /ubbthreads/images/graemlins/wink.gif.

I'll recheck the check valves like you mentioned and then bolt it back on.

Thanks for the quick replies. I appreciate it.

Sean

 

[SeanTR3]

Well, I put it back together without the oil seal and it pumped air so I reinstalled it on the car.

Next I pulled the spark plugs and oiled the cylinders, oiled the rocker arms and cranked it over a few times.

Tomorrow it should start right up!

 

[SeanTR3]

Started the car today and it ran well with no fuel leaks. Now if there was a way to seal up all the oil leaks, but then it wouldn't be a Triumph if it didn't mark its spot.

 

[Scotsman]

The above thread is 13 years old. With that said I would be interested in any updates reg rebuilding these fuel pumps. Specifically:

. How effective is rebuilding these? I have been told by some the failure rate is quite high.

. Moss has a rebuild kit (378-530). Is this OK or are there better kits out there?

. As noted above the Moss kit "does not include seal for diaphragm shaft".Is it still the opinion of folks that this is not necessary? I would have thought the seal holds the shaft so it doesn't rattle about.

. Moss has reproduction pumps (377-000). Are these as good or better than a rebuilt OEM pump. The whole unit is only $21 more than a rebuild kit.

. What about electric pumps? My tank has quite a bit of rust in it and the glass sediment trap is quite nice as it filters out the chunks before they reach the inline filter I also use.

 

[Geo Hahn]

I always used old original pumps that I rebuild as needed. It began when repros with a priming lever were unavailable but I'm now convinced that the old stuff is just fine.

I have never had that shaft seal in mine.

I have seen the Moss pump (of Turkish manufacture) and was not impressed. Doesn't look right, had some plastic part (possibly the thumb nut on the bale) and there may have been an issue with the threads at one point.

 

[2liter4cyl]

I read somewhere that the cork seal on the diaphragm shaft is not too important. The reason given for same was it stops oil from going up to the diaphragm when making HARD right turns! Le

 

[Scotsman]

Interesting you say cork seal. Mine was rubber.

Are there any rebuild kits that you would recommend or avoid. There are a number of outfits that sell them (Moss, BPNW, TRF) ranging from $15 (BPNW) to $62 (TRF, includes seal).

 

[mgedit]

I have read previous threads that suggest that the TRF kit is superior, and as you note includes the extra gasket; however, I have not personally compared the kits from different suppliers. Cheers, Mike