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from what i measure the 90 degree heater hose fitting that goes on the back passenger's side of the motor should be a 5/8 pipe fitting to a 5/8 hose fitting, but i can't seem to find a 5/8 pipe fitting one. the biggest i can find is a 1/2 pipe to 5/8 hose like this one below. are my measurements off?? i measured the fitting and the bracket and they were both at 5/8 pipe.

http://www.ebay.com/itm/90-Degree-Heater-Hose-Fitting-1-2-Pipe-5-8-Hose-1036-/230340560188?pt=Motors_Car_Truck_Parts_Accessories&hash=item35a15e053c&vxp=mtr

Hi, Not sure if this will be of any help but I am currently at work and have just measured a 1/2'' NPT pipe fitting, the diameter across the lower part of the thread is approx 3/4'' so a 5/8'' NPT thread diameter would be even larger than this.
Regards,
Dave.

Hi Again, Further to my last reply I just found a 3/8'' NPT pipe fitting and the lower thread diameter is approximately 5/8''. I suspect the fitting you require is probably 3/8''NPT to 5/8'' internal dia hose.
Regards,
Dave.

Henry,

I bought a longer straight heater hose fitting (1/2" NPT for 5/8" I.D. heater hose) to replace the short one that goes into the water pump of my '55 Clipper. I would imagine you should be able to find a 90 deg. type easily enough. I reused the 90 deg. one that screws into the plate on the back of the R.H. cylinder head.

F.Y.I. when you get to this point: I bought a 90 deg. pre-formed heater hose from NAPA (PN 9810) and cut it to size.

I hope this helps.

(o[]o)

Edit: Henry, et al: Pipe thread size is not the same as U.S. bolt size, it actually measures larger than the fractional size indicates.

when i measure with my calipers the orginal pipe fitting at the arrow that i made in the picture i get 5/8 OD. when i measure the opening of the part that is on the motor it is 5/8.

so it starts at 5/8 and gets bigger to seal up to keep water from coming out.

is this the same as you are measuring? seems like the 1/2 would start at 1/2 and go to 3/4, so 5/8 would be in there before you could thread it all the way in. but 1/2 is too small to start my threading into the head.

maybe i'm confused.

Hank

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i think i just figured it out. the inside diameter on my OEM one is 1/2 and i am measuring the outside diameter, which is 5/8. so if i get a 1/2 npt it will be 5/8 OD and i will be good??

so the link to the one above should work for me.

were you measuring ID or OD....this will confirm i figured it out

Hank, If you are measuring 5/8'' diameter at the arrow you indicate then you have 3/8'' NPT not 1/2'' for instance the temperature sender thread is definitely 3/8'' NPT and I suspect the heater outlet will be the same...
Regards,
Dave.

this is what i got. and i pulled the one from the water distribution manifold as well and it is the same measurements and fits.

the temp sender is def smaller...as you cannot swith the adaptor plates from passenger to driver's side. the smaller hole is for the sender/driver's side and the larger holed plate is for the heater hose/passenger's side.

so if the drivers side is 3/8 then the heater hose is 1/2.

Hank

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I just measured a 3/8'' NPT pipe fitting and get 16.23 mm dia at the same place you are measuring.

as JW quotes Pipe thread size is not the same as U.S. bolt size, it actually measures larger than the fractional size indicates.

Regards,
Dave.

Hank, Another way to check is 3/8'' NPT should have 18 TPI and 1/2''NPT should have 14 TPI...
Regards,
Dave.