Heater hose nipple into manifold question

[blown motor]

As I understand it the pre-70 manifolds were tapped for a 5/8" thread and 5/8" nipple. After that it was 1/2" thread and 1/2" nipple. My nipple is in bad shape so I ordered a nipple kit which came with a heater hose nipple and a bypass nipple. The heater nipple is 1/2" for a 73 340 engine. It doesn't match the old one which is 5/8 thread and 1/2 nipple. The manifold was cast in 72.

I hope this isn't too confusing. I know I did a poor job of explaining it. Has anyone heard of a 72 manifold tapped for a 5/8 fitting? Where can I get a fitting with 5/8 thread and 1/2 nipple? I may look for a helicoil the make the new fitting work.

[72cudamaan]

Never heard of a 5/8 thread on a car. Those pipe nipples have a pipe thread which should be 1/2". The
next larger size should be 3/4". Be careful, you can't measure a pipe thread like a normal pitch thread. Pipe threads
are quite a bit larger due to the depth requirements of the thread.

[ToxicWolf]

There are a lot of 1/2 npt to 5/8 hose. Maybe you have it backwards. Try talking to the people at Summit. They carry a lot of different size fittings like this.

[jhaag]

drive down to your local NAPA and ask to look through their HVAC picture catalog. They will have pictures & part number of exactly what you need and more than likely have it in stock.

[mopardave]

http://www.rosevillemoparts.com/advanced_search_result.php?keywords=hose+nipple&search_in_description=1&imageField.x=0&imageField.y=0

64-69 LA engine Heater Hose Nipple Kit 4 piece

or

70-78 Small Block 2 piece nipple kit

[burdar]

I ran into the same problem. The hose nipple kit I bought came with a 1/2" nipple for the intake. The intake has a 5/8" hole in it. The correct fitting has 5/8" threads and necks down to 1/2". I found the correct one at Mega Parts but didn't want to pay the shipping for one small part. I found a fitting at Advance Auto that will work. I think I saved the box if you want the part number.

[burdar]

The nipple on the far right is what comes in the kit.  The nipple in the middle is the factory piece.  It's 5/8" at the intake and necks down to 1/2" at the heater hose.  The one on the left is a nipple I found in the HELP section at the parts store.  It did NOT work. 



Here is the one I bought. Four Seasons part#84712
http://board.moparts.org/ubbthreads/upload2/7201495-DSC01569.JPG

[anlauto]

WoW...that center one would certainly be a problem solver...I run into this a lot with big blocks

[burdar]

I edited my above post with the Part# for the nipple I bought.  Like I said, Mega Parts sells the correct one but I couldn't justify the cost.  I think the one from the parts store was $5.  The correct one was $10 or $12 plus shipping.

[anlauto]

Picture saved....I didn't even know that puppy existed

[blown motor]

Darren, the one in the middle is the one I have only yours looks a lot better than mine. The one on the right is what I got in the kit. I don't think we have Advance Auto here in Ontario and shipping across the border would be a lot more than $12. Hmmmm 

[burdar]

Look in the link I posted. That brand should be sold in other parts stores I think.

[blown motor]

I googled Four Seasons part # 84712. It's available from lots of places. Of note was Amazon.com (US) for 6.29 and Amazon.ca (CDN) for an amazing 21.96 Unbelievable.

Thanks Darren. I'm sure I'll get one, just need to figure out where.

[72cudamaan]

The nipple on the far right is what comes in the kit.  The nipple in the middle is the factory piece.  It's 5/8" at the intake and necks down to 1/2" at the heater hose.  The one on the left is a nipple I found in the HELP section at the parts store.  It did NOT work. 



Here is the one I bought. Four Seasons part#84712
http://board.moparts.org/ubbthreads/upload2/7201495-DSC01569.JPG

Actually the one in the middle is 1/2" pipe thread and the one on the right is 3/8" pipe thread. The one on the left looks to be a straight thread so it definitely won't work. A pipe thread is tapered so you will get a different measurement depending on where you measure it. Again, there is no such thing as a 5/8" pipe thread.

[burdar]

The one on the left screwed into the manifold just fine.  It's the heater hose that wouldn't stretch over the end.  That's what happens when you don't have the old part in hand when you're at the parts store.  I'm pretty sure the hole in the intake was 5/8" in diameter.  That must translate to 1/2" pipe thread?

Summit lists one as well...
http://www.summitracing.com/parts/fss-84712