Having trouble finding fittings for my fuel pump.

[Big Ray]

The pump I just bought came with straight brass fittings. I bought some 90's but the thread is wrong. I need 2 90" fittings, 1/4" nps threads with a 5/16" barb. nps threads are straight. I have looked all over the interwebs and all I can find are fittings with tapered threads.

help!

and as always, thanks in advance!

 

[frankin5]

Jeg's #16031
part# 555-16031
1/4" npt to 5/6th barb
90Degree

NPT is national pipe threads and they are tapered. If straight they may be a flare fitting and it is not tapered

 

[Big Ray]

Yes, I know NPT is tapered. I have NPS threads on the pump..

From Walbros own site:

Mechanical

• Inlet & Outlet Size: 1/4-18 NPSF
• Inlet Filter Screen: 70 micron
• Magnetic Trap: Yes
• Outlet Check Valve: None

I broke out my calipers and did some measuring, there is a difference.

this is from a machinist supply site:

NPSF National (American) Pipe Straight (parallel thread instead of taper) Fuel
* references internal female thread. Commonly mated w/ male NPTF although not ideal w/ male taper to straight female

I've never encountered this in all my years of wrenching....

 

[frankin5]

http://www.depcopump.com/datasheets/walbro/FR-PumpBrochure.pdf
they list the 90 degree fitting your looking for.
Part # 128-3094:90o1/8-27NPTF to 5/16 Hose Barb Fuel
Fitting or Part # 128-3061 90o 1/4-18 NPTF to 5/16 Hose Barb Fuel
Fitting

 

[diesel4me]

Pipe threads can be "straight" too,but its uncommon as hell--most things like fuel & tranny lines use straight (machine) thread fitting and a flare to seal the connection--some though,rely on a flat faced nut with a fiber washer or o-ring that seals against the casting on the part in question..I'd think a straight pipe thread would have to seal that way too..

 

[Big Ray]

ah, I thank you sir! I have 6 of them on the way, at @$.41 each! Gotta have spares....

 

[diesel4me]

Yes, I know NPT is tapered. I have NPS threads on the pump..

From Walbros own site:

Mechanical

• Inlet & Outlet Size: 1/4-18 NPSF
• Inlet Filter Screen: 70 micron
• Magnetic Trap: Yes
• Outlet Check Valve: None

I broke out my calipers and did some measuring, there is a difference.

this is from a machinist supply site:

NPSF National (American) Pipe Straight (parallel thread instead of taper) Fuel
* references internal female thread. Commonly mated w/ male NPTF although not ideal w/ male taper to straight female

I've never encountered this in all my years of wrenching....

I like the last paragraph--"references internal female thread --commonly mated with male NPTF although not ideal w/ male taper to straight threads"..

So,I decipher that to say-- "it's not the right way to do it--but everyone does ".......

I'd use teflon tape or pipe dope and go easy on the torque--tapered male things inserted into straight female things, tends to split the female open....(this may apply to humans also !)....

 

[Big Ray]

you are correct, on all counts!

I put regular npt fittings in, but they only sealed about a thread and a half. Should be good to go when the new ones get here.

 

[Big Ray]

ah, I thank you sir! I have 6 of them on the way, at @$.41 each! Gotta have spares....

WTF...Got an email from the store saying I ordered throttle return springs!
I can not believe this chit......

 

[Big Ray]

O.k., found a boat equipment store that sold Walbro pumps, 2 fittings are on the way.