air compressor regulator....................wore out...

[Freightrain]

Well, it was starting to act up the last couple trips out. Fire truck up and it would not want to get over 30 psi. Give the motor a couple revs and it would then continue up and run fine for the trips. Was wondering what was failing.

Went to get truck out of garage Sunday morning and it wouldn't get over 30 psi, period. Played with it, tapped on regulator, but to no avail. I pulled it off the firewall and pulled it apart. Seems okay, but two o-rings were not looking good(kinda flattened out). I oiled them up and tried again. Nope, not making air. Ugh. Seems maybe some heat might help(it was only 40* out). I got my little propane out and waved it over it for a few moments. Presto- it starting climbing air pressure. Whew. I was trying to get race car transfered into garage and needed the truck.

I pulled it apart again this morning and am going to run up to store and get a new pair of o-rings for it. Should make it good to go for another 50 yrs??

WIth other guys having issues with theirs, I guess after 11 yrs mine had to fail. Oh well, at least I'm not stranded on the side of the road.

[39 Baby Mack]

Larry

It's probably a very common B&W D-2 air governor, not that expensive.

Why not just get a rebuilt one?

Ron

[Mike]

Good to hear you are not stranded some place Larry. Although those regulators are not but about $11.00. Good to know it is o-rings only and not something major. Do you ever drain those tanks to keep the moisture out of the lines? Seems like all of those B Models need heat to make them perform at peek.

mike

[Vladislav]

I also have an issue with reg.

Not shure although.

My R makes up 70 psi but gets air off to the outside. Nearly one time per minute.

Suppose that valve must to offload compressor for not producing accessive air.

Am I right?

I saw a regler on Watt's online for not a great money but prefere revise my for a first.

In a case i need to worry about the regler but anything else.

Vlad

[Freightrain]

Well I'd just get a new one but if all it is wrong is o-rings then for less the a buck it will be fixed. Nothing much to it and I've heard it leaking lately(getting air past the o-rings on piston). I will find out later today and I'll report back. Might even take a couple pics.

Mike, the tanks stay dry with no oil from the rebuilt compressor and doesnt see alot of temperature swing since staying in the garage. The govenor was clean inside as it pulls off the junction block on firewall so it doesnt see oil or water.

The heat I applied was to soften the rubber so it would seal better. Seems to help when they are worn out and cold.

[Freightrain]

Ok, got home with parts and put it together. Works NICE!! Doesn't leak after shutting truck off(you could hear it before).

Two o rings(1.25 x .093) for a grand total of $0.87

You can see the top one I had to break to get off, it was hard as rock.

A shot down the hole. I did wipe it out, but it was clean, no sludge. I few drops of oil on the o rings and I slid it back together and installed the snap ring.

Not bad for a few minutes work and less then a $1 in parts.

[Freightrain]

Vlad sounds like your safety valve is popping off and releasing air from the tanks. They are right on the tank, and could be weak? Usually they are suppose to be up around 150 psi before letting off.

Not saying it couldn't be the govenor?? Mine only leaked enough to be heard after truck is off. Then it had a slight hiss coming from the end where the snap ring is at. I think that is why truck drained air pressure so quickly anymore.

I did have a air release sound this past summer, running down the road, never sitting still. Just a quick "hiss" and would never affect air pressure gauge. Never at cut in or cut out pressure. I searched all summer for that noise. Not sure, maybe this had something to do with it??? Won't really know til next spring when I get truck out and run it again.

[Vladislav]

Larry, thank you for thoughts.

Yes, you are true, the air releases at 150 psi or near of. Don't remember well, I haven't run the truck too much.

60 is the pressure for switching off the warning light.

Some valve releases the air from time to time with short portions if I'm not using brakes at the while.

Standing in a city jam I used to my area I hear that air shots every minute but treading a break pedal from time to time I get it off.

The previous owner said he needed to revise a valve an a fire wall but didn't.

I know I must learn everything about it in a book and make it up.

Just saw your issue and meant you met anything like my one.

About O-rings I'm always on your side.

Prefere to be shure of what is inside and understand roots of a problem.

And a money spend is not the main reason.

[Freightrain]

Let the truck idle and walk around to the air tanks. Should be relief valves installed(at least one) and listen to see if it pops off while sitting there. It should if your air pressure gets to 150# on the dash guage.

If the govenor is stuck, then it won't release the unloader valve in the compressor head to make it just "freewheel". Thus over pressurizing the system and makes the releif valve let go to keep things from coming apart at the seams(like the air tanks). Mine was leaking so bad it would not "cut in" and allow compressor to make air. Just the opposite of your situation.

If I'm thinking correctly, the govenor supplies air to the unloader, once it reaches maximum(120 psi) it pushes on unloader valve to release compression in pump(freewheeling it). Once air pressure drops down to 90psi(cut in), it releases the unloader valve to make compressor work again.

Now, if you have an air dryer, this will also "spit" occasionally. About the size of a coffee can, hanging on the frame. This is just letting moisture out of the lines. Not relieving pressure in a safety aspect.

Here is a shot of my govenor:

One copper line in from air supply manifold on firewall, the soft line goes to the compressor head.

[Mike]

Hey Larry. This may be off the subject but what is the smaller pipe coming out of the firewall under your larger intake pipe? Mine does not have that pipe. There is a flat metel plate over the hole.

mike

[Mike]

I may have figured it out. It is the pipe that loops into the intake.

mike

[Freightrain]

Yup, mine has the split intake. One pipe around front, one around back.

That ring you see is the metal clamp that supports it and attaches to a head stud.

[Vladislav]

Larry, thank you for the lection.

Sorry I read it later but it all looks like you describe.

So will revise the air governor. Mine looks yours alike.

Now it's a cold time at me, not a season of hobby trucking.

Need to wait for the spring.

[oilburner]

Larry, thank you for the lection.

Sorry I read it later but it all looks like you describe.

So will revise the air governor. Mine looks yours alike.

Now it's a cold time at me, not a season of hobby trucking.

Need to wait for the spring.

Does your truck have a air dryer on it, this can also cause problems with the regulator. It has a line that usally comes from the regulator to the dryer vavle and when presure gets to 120 it opens the vavle for a quick secound to purge water out of the system.

[Vladislav]

Yes, the truck does have.

As far I think about different issues on the truck as far I get a mind of total rebuild.

Troubles are floating out any point where Russian mechanics put their hands on.

[rsb502]

Well I'd just get a new one but if all it is wrong is o-rings then for less the a buck it will be fixed. Nothing much to it and I've heard it leaking lately(getting air past the o-rings on piston). I will find out later today and I'll report back. Might even take a couple pics.

Mike, the tanks stay dry with no oil from the rebuilt compressor and doesnt see alot of temperature swing since staying in the garage. The govenor was clean inside as it pulls off the junction block on firewall so it doesnt see oil or water.

The heat I applied was to soften the rubber so it would seal better. Seems to help when they are worn out and cold.

next the spring inside will rust and break and youll be back in it again, just get a d-2 governor and swap it out, almost every parts place has em in stock I actually keep one or two here at the house last Bendix brand I bought was $19 and the power products was $14.

[rsb502]

Larry, thank you for thoughts.

Yes, you are true, the air releases at 150 psi or near of. Don't remember well, I haven't run the truck too much.

60 is the pressure for switching off the warning light.

Some valve releases the air from time to time with short portions if I'm not using brakes at the while.

Standing in a city jam I used to my area I hear that air shots every minute but treading a break pedal from time to time I get it off.

The previous owner said he needed to revise a valve an a fire wall but didn't.

I know I must learn everything about it in a book and make it up.

Just saw your issue and meant you met anything like my one.

About O-rings I'm always on your side.

Prefere to be shure of what is inside and understand roots of a problem.

And a money spend is not the main reason.

Vlad does your truck have an air dryer that is popping off frequently? I think that is what you are talking about, if so the air dryer can pop early and repeatedly for several reasons, 1 is the governor, 2 is a leak in the unloader line its one of the two plastis 1/4" air lines going from the dryer to the governor, 3 is the unloaders in the head on the air compressor, 4 is a bad gasket on the governor, and 5 would be a bad purge valve in the dryer. I always rebuilt my air dryer once a year this consists of a purge valve kit and a new dessicant cartridge , the unloaders in the air compressor have o-rings and a plastic back up ring that wear out and need to be replaced also, the governor can be replaced for less than $20 , the unloader rebuild kit for the air compressor is $40 and the purge valve kit and dessicant cartridge for a Bendix AD9 dryer will run about $160 for both. Use soapy water to check for leaks in the small air lines from the governor if it loses pressure it will pop.

[Freightrain]

next the spring inside will rust and break and youll be back in it again, just get a d-2 governor and swap it out, almost every parts place has em in stock I actually keep one or two here at the house last Bendix brand I bought was $19 and the power products was $14.

Well, maybe I'll get one and throw it in the truck for a rainy day(that is likely when I'll have to replace it anyway LOL). There was enough oily goop that the spring was not rusty at all. You never know though!

[Vladislav]

Vlad does your truck have an air dryer that is popping off frequently? I think that is what you are talking about, if so the air dryer can pop early and repeatedly for several reasons, 1 is the governor, 2 is a leak in the unloader line its one of the two plastis 1/4" air lines going from the dryer to the governor, 3 is the unloaders in the head on the air compressor, 4 is a bad gasket on the governor, and 5 would be a bad purge valve in the dryer. I always rebuilt my air dryer once a year this consists of a purge valve kit and a new dessicant cartridge , the unloaders in the air compressor have o-rings and a plastic back up ring that wear out and need to be replaced also, the governor can be replaced for less than $20 , the unloader rebuild kit for the air compressor is $40 and the purge valve kit and dessicant cartridge for a Bendix AD9 dryer will run about $160 for both. Use soapy water to check for leaks in the small air lines from the governor if it loses pressure it will pop.

Thank you, I'll keep that all in mind. I have no plans for my R during this winter. Not pleasure to work laying in snow, unable to drive out due to lot of ice on my street's pavement. I live a little not run-through street in a village near the city. Neibourghs open windows and look with wide opened eyes each time I drive Mack to/out of my home.

[Buickwrench]

I also have a 1987 RW713 that has very low mileage (4500) that builds air at a snails pace and does not have enough volume to air up a towed unit. It is a heavy wrecker. I don't hear any leaks, and it does eventually fill. It is a V8 with what looks like a Borg Warner compressor. Any help would be appreciated. Marty

[David]

I also have a 1987 RW713 that has very low mileage (4500) that builds air at a snails pace and does not have enough volume to air up a towed unit. It is a heavy wrecker. I don't hear any leaks, and it does eventually fill. It is a V8 with what looks like a Borg Warner compressor. Any help would be appreciated. Marty

We're definitely going to need some pictures of this unit.

[Buickwrench]

Sorry.. Bendix compressor, BW regulator

[Vladislav]

I suppose BW means Bendix Westinghouse.

Doesn't it?

[leversole]

Borg Warner!

[rsb502]

should be a tru flow 501 on the E9 truck, they get old and pump slow when the rings get worn down, its easiest to just replace the compressor than to try to rebuild it.