iDRY Vacuum Kilns

Sponsors:

Old Fleetstar won't make air pressure

Started by nastcat, July 27, 2015, 08:30:16 PM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

nastcat

I have an 74 1910 fleetstar dump truck, with a 549 gasser hooked to an automatic in it, and the compressor seems to make air but won't build any pressure. I have been scratiching my head with this problem for a bit. Any direction would be appreciated.

East ky logging

I had trouble last winter with a gmc they was a valve above the rear end was stuck open and dumping the air out. It was barley noticeable but it was letting more air out than was coming in. Start it up and look for a air leak somewhere in the system
They who can give up essential liberty to obtain a little temporary safety deserve neither liberty or safety- Benjamin Franklin

North River Energy


Had a similar problem while putting up my '68 Dodge c800 for the winter a few years back.  Seemed to be related to the cold and damp on that particular day, as it has not been an issue since. I think the unloader valve was frozen open.

Was your truck fine and then suddenly not, or has it been out of service for awhile and now has a problem?

I've got a fitting to put shop air directly to the truck systems by way of an air chuck on the tank.  Leak finding is a lot easier when the engine is off. 

Saves gas too.
That 549 certainly has a sound doesn't it?

starmac

Sounds like a bad govenor, easiest way to tell is to loosen the 2 bolts that hold it on, so that the gasket under it leaks. If it is the govenor, it will build air, but won't shut off while the gasket is leaking, so you will have to watch it, so it doesn't blow anything.

A leak big enough to keep pressure down to zero or close is hard to hear. It is much easier to hook to shop air, so that it makes noise under pressure. The air drier also causes this, but I doubt the 74 has a working drier, it seems most that old has been bypassed, if they ever had one to start with.
Old LT40HD, old log truck, old MM forklift, and several huskies.

nastcat

It was sitting for a year or so. This spring it wouldn't build air when it was started.

Gearbox

Check valve stuck going into wet tank or an unloader valve in the top of the compressure . Gearbox
A bunch of chainsaws a BT6870 processer , TC 5 International track skidder and not near enough time

nastcat

I am resurrecting this old post because I am back to working on the truck again. Changed the air governer on the compressor and it didn't make any difference. Took the head off the compressor and found one of the exhaust valves were stuck open. Thought I had the problem figured out (and maybe I did). Put the head back on the compressor and hooked everything back up. Fired it up and still no air pressure, so I took the compressor off and brought it home with me. I took the head off the next day and found a kernel of corn in the intake passage and when I shook the head some seeds fell out that looked like black popcorn. I guess that some type of rodent used the air intake filter area for seed storage and probably the first time it was fired up it sucked  debris into the compressor.  I need the figure out the best way to clean the head out. Does anybody know how to take apart the head? I mean remove the valves and further disassemble the head. I have accesss to an aqueous solution dip tank. If I soak the head in the tank are there seals in the head that I might damage? I have searched the internet and found very little info on the compressor. I would love to find a gasket and seal kit for the compressor.

  

  

 

snowstorm

air cooled compressor. dont see those very often. bendix made compressors for all the truck builders. just go to a junkyard and find a belt driven compressor. its no big deal to use a water cooled one

nastcat

The compressor has an water jacket in the head. The bottom of the compressor dumps back into the engine crankcase, is this common? Hear are a couple more pics. I still would like to know if I can disassemble the head farther. The exhaust valves look like you should be able to turn them out with a large allen wrench. I dont see how the intake valve can be disassembled.


  

  

  

 

snowstorm


nastcat

The oil feed pumps oil into the side of the compressor. The return is the open bottom that bolts to the top of the engine and drains back to the engine crankcase.

nastcat

I finished with the compressor. Painted it up nice and pretty put it back on the truck. Low and behold we now have air pressure. The compressor had sucked seeds and junk out of the air filter into the head of the compressor. When I removed the intake valves, each valve had a hull of a seed stuck between the reed and the inlet port of the intake valve.

sawguy21

Good job. I guess you will be servicing filters more frequently ;D
old age and treachery will always overcome youth and enthusiasm

nastcat

I definately will make sure the air filter is serviced before trying to start after setting for an extended period of time. The truck has yet to make it home because I brought it and the previous owner is the one that started it up without cleaning the filter. Then nobody could figure out why the truck wasn't making air pressure.

Thank You Sponsors!