350 cummins air compressor

Moline_guy · May 15, 2017

Looks like a blew the head gasket on the air compressor on a 83 freightliner, notice the gap between the two pipes. I have never had this apart before is it simply removing the air governor and then the compressor head and replacing gasket? It is hissing air out of this gap and won't build air, I replaced the air governor before I noticed the air coming out of the head. Thanks for any help or information.

Ragnarok · May 15, 2017

Some of the older Cummins air compressors don't have head gaskets....depending on a perfectly flat set of surfaces to seal.

Phil9N3667 · May 15, 2017

If I remember correctly, that's the unloader valve plate that's leaking. The top plate can get warped and cause what you see. The head itself is what the two water lines go into and not apt to blow a gasket unless there's a blockage in the discharge pipe to the 'wet' tank. Make sure the discharge line's not carboned up. Find an old timer truck mechanic that keeps the older trucks running and get him to check it for you. I haven't worked on one of those compressors in probably 8 years or so. Good luck.

guido · May 15, 2017

Hello Moline_guy,

You can get a reman compressor. Looks like a twoflow 500 compressor. Removing the pump and the compressor requires 1/2 moon wrenches, for the bolts on the block side. You will also need to replace the water pipe's "o" rings which are square. 1/2" if I recall correctly. Not to bad of a job with the proper tools,

Guido.

the tractor vet · May 15, 2017

Yep ya just get a Rebuild and replace . On my 4300 Binder i had the truflow twin . and yep ya need the Cummins wrenches . First the injection pump comes off then the compressor . I have all the tools to work on them as i did 99% of my own work. about and hour off and back on .

MT RON · May 15, 2017

Wow shoulda lasted longer than that!

Trkr · May 16, 2017

Not a Tu Flo,it's a single piston.If you replace with another single piston compressor,it should be timed to no 1 cylinder.Tu flos balance themselves,don't have to be timed.

Trkr · May 16, 2017

You can pull the compressor with the PT pump still attached,just a little more awkward to handle.PT pump is easier to remove this way.You will need a special curved wrench to get the back lower compressor bolt off and on.

the tractor vet · May 16, 2017

Yes you can but it has to come off anyway and i always start at the back and move forward. Yes i know it takes the compressor / pump wrench and yes i have these special tools along with the valve wrench the jake brake socket the injector rocker the dial indicator for setting the injectors the small torque wrench for the injectors fro the big cams as well as all the special tools for the 5.9's and the detroits and the old A/C industrial engines some Cat tools , a semi load of I H special tools , well maybe not a semi load but my Dodge one ton sure has a load of them . Tools my boy is not something i am lacking in that dept.

UtMatt · May 16, 2017

Get these...
1 154018 gskt
1 4920062 gskt
1 ar12719 unloader oring kit
2 3103015 water grommets
and 1 3201386 gskt if you remove that intake fitting.

MARK ROBKE · May 16, 2017

It's been a long time,but I think you can pull the unloader and the head together.You HAVE TO drain the coolant no matter what you do to fix it.But I would try to pull the head off any way,to inspect it.If you can get it off easy,it would be worth it to try the gasket set.If you have to pull the compressor,as others said,the back bolt is a little mean.I heated and bent and ground a wrench to fit that back bolt-take it out FIRST.You can pull the pump and compressor together,but that is silly-it's heavy enough separated.And there is a plastic coupler between the pump and air compressor,replace it too.Mark

350 cummins air compressor

Moline_guy

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Ragnarok

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Phil9N3667

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guido

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the tractor vet

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MT RON

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Trkr

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Trkr

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the tractor vet

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UtMatt

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MARK ROBKE

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