Fuel Pump Relocation

U

unbeam

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If that doesn't work, www.hoseandfittings.com, go to fittings, then brass, then to pipe-British, then search the combinations. I believe it is 5/16", which is 05 by their nomenclature, but is not very common and in searching I could not easily find any.....
Save it for reference for other odd British fittings, like off the SU fuel pump.
 
K

KettleCarver

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198
Before I get too far into this project, I decided to check out the fuel pump that came with the car. It is a similar shape to the stock SU, however the input and out put are more of a flow thru arrangement, rather than stacked one on top of the other like the SU. It is pretty loud, and it was stamped "Made in China" on the bottom. I am not fond of Chinese made products and have no idea what brand it is.

I was thinking of buying an SU pump to insure that replacements would have a standardized input/output. Are the SU's quiet? Is Sunbeam Specialties the best place to buy one?

If you have other better alternatives that you recommend, I would like to hear that too.

Thanks
 
0neoffive

0neoffive

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KettleCarver said:
Before I get too far into this project, I decided to check out the fuel pump that came with the car. It is a similar shape to the stock SU, however the input and out put are more of a flow thru arrangement, rather than stacked one on top of the other like the SU. It is pretty loud, and it was stamped "Made in China" on the bottom. I am not fond of Chinese made products and have no idea what brand it is.

I was thinking of buying an SU pump to insure that replacements would have a standardized input/output. Are the SU's quiet? Is Sunbeam Specialties the best place to buy one?

If you have other better alternatives that you recommend, I would like to hear that too.

Thanks
Click to expand...
The correct SU is priced about the same no matter where sourced. There is a repair guy in San Diego that I have used who may have extra product. Just sayin'
 
Austin Healer

Austin Healer

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0neoffive said:
These comp nuts are 1/2 BSSP . The transfer nipple measures 1/2” diam and I suppose you could do the math and count the threads per inch with a good magnifier.

View attachment 18929
Click to expand...
No they aren't! 1/2 BSPP is 14 threads per inch. I just pulled a spare crossover tube out of my stash... The threads are 20 tpi. They are parallel, not tapered. I did find a brass nut (early Mk1), later cars used a steel nut. A lot of fittings (fuel, oil pressure lines) on British cars used Whitworth wrenches and have weird thread counts.. I guess this is one of them! Baffles me, I couldn't find any type of tubing fitting with a 20 tpi thread count in parallel type. No wonder they're hard to find. In any event, I do have a spare!
 
Austin Healer

Austin Healer

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Finally figured out the thread type. It's called UN for Unified National. The fitting size is 5/16-20tpi. Tubing and pipe fasteners are sized based on the tubing or pipe and not the diameter of the threads... Unified National is a British thread system and it makes total sense as they refer to their screws and bolts as UNF and UNC. F=fine, C=coarse. UNF/UNC is the same as out SAE/USS
 
K

KettleCarver

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198
Austin Healer said:
Finally figured out the thread type. It's called UN for Unified National. The fitting size is 5/16-20tpi. Tubing and pipe fasteners are sized based on the tubing or pipe and not the diameter of the threads... Unified National is a British thread system and it makes total sense as they refer to their screws and bolts as UNF and UNC. F=fine, C=coarse. UNF/UNC is the same as out SAE/USS
Click to expand...
Thanks for the info. It is starting to make more sense now that I know the difference between UNF/UNC.
 
K

KettleCarver

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Messages
198
I ordered a new SU fuel pump and fittings yesterday. I still need to source the fuel line. I am leaning toward using stainless steel.

I was thinking of using fuel rated teflon tape on the crossover tube to fuel line connection. Or, do yo guys use something else?
 
Austin Healer

Austin Healer

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KettleCarver said:
I ordered a new SU fuel pump and fittings yesterday. I still need to source the fuel line. I am leaning toward using stainless steel.

I was thinking of using fuel rated teflon tape on the crossover tube to fuel line connection. Or, do yo guys use something else?
Click to expand...
No sealant of ANY kind at the unions.
 
0neoffive

0neoffive

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KettleCarver said:
I ordered a new SU fuel pump and fittings yesterday. I still need to source the fuel line. I am leaning toward using stainless steel.

I was thinking of using fuel rated teflon tape on the crossover tube to fuel line connection. Or, do yo guys use something else?
Click to expand...
Just a heads up: On occasion, I've noted that those supplied out/in fittings have incomplete machining. Quite often the 5/16" line connection does not have the correct "pocket" for the tube to slide in nor the bevel to catch and seal the compression union. It's easily solved with a couple of drills but we shouldn't have to do that.
 
Austin Healer

Austin Healer

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0neoffive said:
Just a heads up: On occasion, I've noted that those supplied out/in fittings have incomplete machining. Quite often the 5/16" line connection does not have the correct "pocket" for the tube to slide in nor the bevel to catch and seal the compression union. It's easily solved with a couple of drills but we shouldn't have to do that.
Click to expand...
I've had the same problem
 
K

KettleCarver

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198
The new SU fuel pump came in today. What are those 2 silver fittings for? Some sort of vent? What are they connected to?

SU fuel pump.jpg
 
Austin Healer

Austin Healer

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nothing on the top one. the one near the base had a clear tube Like the w/s washer hose) and it gets routed through the hole on the RH side of the bulkhead in the trunk
 
hottigr

hottigr

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Austin Healer said:
nothing on the top one. the one near the base had a clear tube Like the w/s washer hose) and it gets routed through the hole on the RH side of the bulkhead in the trunk
Click to expand...
The top one in the photo or the top one on the pump (asking for a friend):)
 
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