M38a1/M170 Ventilation valve

bl5211a · Post by **bl5211a** » Sat Jun 07, 2014 4:53 pm

Hello, I have a 1955 M170, is it suppose to have a ventilation valve on left side of engine or a 2" hose. Mine has a 2" hose and didnt know if it was a field fix?

Brian

Post by **wesk** » Sat Jun 07, 2014 6:32 pm

All M38's, M38A1's & M170's came with a PCV valve on the left side valve cover area. Only the early M38A1's (52-53) and USMC contract M38A1's came with the fording valves. Later were sometimes added and earlier were usually removed and substituted with a short hose. But the PCV valve (Positive crankcase ventilation) stayed on all. If it was removed by a not so smart prior owner then get one and re-install it.

Most A1's look like this with the PCV valve still there and the fording valve gone.

bl5211a · Post by **bl5211a** » Sat Jun 07, 2014 6:46 pm

Perfect, this is exactly the info i needed.

Thanks!
Brian

bl5211a · Post by **bl5211a** » Sat Jun 07, 2014 6:50 pm

On a different subject, where did u get that 6" flexible fuel line. I could use one.

bl5211a · Post by **bl5211a** » Sat Jun 07, 2014 6:55 pm

Also, which direction should PCV go..

Post by **wesk** » Sat Jun 07, 2014 7:20 pm

This is the original plumbing on the 52 & 53 M38A1's.

Here's a new in the crate 1962 issue replacement engine:

In the image below from TM 9-8014 Fig 52 dated April 1955, you see the short piece of rubber hose instead of the fording valve.

In this image below from TM 9-8015-1 Fig 4 dated Mar 54, you see the fording valve is included.

Post by **wesk** » Sat Jun 07, 2014 7:25 pm

The whole system, both standard crankcase ventilation and the fording valve systems are explained in great detail in TM 9-8015-1 chapter 6.

If you don't have it now, download it free:
http://www.willysmjeeps.com/v2/modules. ... tit&lid=85

skyjeep50 · Post by **skyjeep50** » Sun Jun 08, 2014 9:59 am

bl5211a - flexible fuel lines are available from a number of MV parts suppliers. You could try Midwest Military.

bl5211a · Post by **bl5211a** » Sun Jun 08, 2014 10:34 am

Thanks..

Here's how they ended up:

Post by **wesk** » Sun Jun 08, 2014 10:46 am

You can also take your old line to any car parts dealer that can use the printed catalog and they can locate the same or close enough with a female 5/16" steel tube fitting on one end and a male 5/16" steel =tube fitting on the other end.

bl5211a · Post by **bl5211a** » Tue Jun 17, 2014 5:26 pm

thanks..