doubleclutchinweasel

I found a mail-order outfit that can get these. So, I ordered 2 left and 2 right pieces. Should be here in a couple of weeks.

As soon as it quits raining, isn't 120 degrees, and my shoulder and elbow quit killing me, I'm going to pressure wash 4 decades of crud off the steering knuckles, and see what kind of shape the kingpins, bushings, and thrust bearings are in. I plan to replace them all anyway, but it would be nice to find tha it didn't have to be done right now. I'd really like to finish all the air system first, THEN work on the front end. Oh, and I do have 1 broken leaf on the left front spring. I'll need to fix that pretty soon, too.

Got my North Carolina "Weighted Antique Auto" tag today! Those guys sure know how to make money!

More to come...

Kent

Okay...

I figured out that these are Bendix "DD3" chambers, or an equivalent. They were most commonly used on buses. Lots of folks on bus and motor home forums talk about them and how to change tham out. So, I'm not in new territory here.

And, apparently, you do just remove the override circuit, and upgrade to a more modern chamber.

As near as I can tell, these (and the service chambers on the other axle) are size 24 chambers. But, I am not 100% sure, as old chambers and equivalent new chambers vary in appearance and outside dimensions.

If this tendonitis would ease up in my shoulder and elbow, maybe I could crawl around under there and see what the heck's going on!

More to come...

Kent

Looks like I can change this over to a "regular" spring brake cannister, and remove the emergency release mechanism. I am currently looking around to see what is available.

These cannisters are fairly small, and there isn't much room to go up to a larger size. As near as I can tell, the rears are only size 20 or 24s. I see that bendix makes a 20/24 and a 24/24, one of which might physically fit. To counteract the relatively small cans, they use a fairly long slack adjuster (7"). So, I probably need to stay with the same cylinder area.

It would help if I could find some numbers on the old parts! I'll keep looking.

More to come...

I took one slack adjuster loose to see what was in there. The center bolt and washer do indeed hold a more-or-less standard adjuster in place.

The cam shaft is 1-1/2" X 10 splines, which is fairly standard. The adjuster length is 7", and is offset about 5/8".

The Bendix numbers I found in the book are 279946N and 279947N. These look right. Now, all I have to do is find some "in-stock" somewhere!

The air compressor is internally lubricated from the back of the auxiliary drive shaft in the engine and

drains back thru the flange where it is mounted to the block.

The coolant lines are the two #6 aeroquip lines that you show in your photos one running in the back to the block

the other running to the bottom of the water pump.

The smaller #4 aeroquip line coming from the pad on the front of the compressor goes to the air governor which

controls the cut in and cut out of the compressor.

Ron

That all makes perfect sense. Thanks, Ron.

Kent

More questions!

I was looking at the Tu-Flo 600 on my '70 R600 (ENDT-673C), and trying to figure out the plumbing.

The air intake is from the pressure side of the turbo, and the outlet is obvious. But, I'm not too sure about the oil and water lines.

I had read in another thread that the oil supply is actually fed into the crankshaft through a tube on the back of the drive shaft. But, I've also read that these compressors can be fed externally. And, I am not sure where the oil return is. I would assume it would have to be at the bottom of the crankcase, gravity feeding back to the engine. But, I'm not sure.

I am not even certain that there is cooling water running to the unit! If not, where are the best places to tie into the engine cooling system to provide supply and return water? Maybe tee into the fittings which supply water to the cab heater box? I don't see any plugged-off lines anywhere that look like anyone has removed any plumbing. Or, are 2 of the lines in the pics, below, water lines?

I have located 3 external lines on the compressor, but am not sure what does what. I am attaching pictures, below.

The left picture clearly shows the inlet and outlet. It also shows 2 smaller lines plumbed-in. The right picture is of the back-side (against the block), and shows a third line plumbed-in. Could 2 of these (the 2 on opposite sides of the body) be coolant lines?

Please help!

Right here, perhaps?

Here's what they looked like...

I'm thinking this whole rear mess needs to be upgraded!

The small reserve air tank in these pictures, I assume, is an isolated air supply specifically to release the parking brakes to allow you to move the truck off the railroad tracks before the train comes!

some of them had a drain plug right in the bottom metal radiator hose. this is the metal part of the hose that attaches between the engine and radiator with two short pieces on either end.

Hadn't looked there. Will check it out.

Thanks,

Kent

Might have to post some pictures for us to see...never seen three brake lines to a brake chamber! Plus, you cannot "override" the spring brakes with no air!

Where does the "third line" go in, the service chamber (front) or the emergency chamber (rear).

This is a new one on me...

I'll get you some pics soon. It's weird! The service and parking brake hoses go into what appears to be the "wrong" end of the chamber. And. the 3rd hose goes into the top of it. Makes no sense.

I'll get pics...

Another of many projects...

I'm looking at the spring brakes on the rear of my '70 R600. They are an old-type spring brake, with no provision for a "caging" tool.

They are also a bit rough, and are on my list of goodies to replace...very soon.

But, the old air system uses 3 lines to the brake chamber; 1 for service brakes, 1 to release the spring brakes, and (apparently) 1 to override the spring brake in the event of main system air loss (via dash-mounted valve).

None of the current brake chambers I can find have 3 ports, instead having only 2. I am assuming these new chambers either did away with the emergency override, or the valving/relays are set up to deliver this emergency override through the normal spring-release port.

Anybody been there/done that?

I see that Bendix has some different service relay valves, and at least one of them has some type of provision to modulate the spring brakes through the foot valve in the event of main system air loss (R14, I believe it was). But, they don't go into great detail about it. I have emailed them, and asked for clarification, but I'm not going to hold my breath waiting on a response.

Thanks,

kent

Well there should be a drain plug on the bottom. Who knows what a previous owner did?

Since you are changing hoses anyway, get the new bottom hose in your hands to check that it is correct.

If it correct, then just take a razor knife and slit it and start it draining. Can control the flow better than just pulling it off straight.

Jim

Yeah, that was my plan "B"! I was hoping to find a drain in the bottom.

You said "plug", not drain cock. So, am I looking for something fairly flush in the bottom of the tank(s)? Possibly with a recess for a square or hex key to remove it?

Thanks,

Kent

Silly question!

How do I drain the radiator on my "new" 1970 R611? LOL!!

I looked on the bottom of the radiator, but did not see a drain cock or drain plug.

I need to replace all the hoses, and would prefer not to get drowned.

Also, is there a plug somewhere near the top of the engine to help purge the air out of the system when re-filling?

Thanks,

Kent

Well, I finally did it!

Went to Knoxville today, and brought it home.

Put belts on it, checked everything out 1 more time, threw in a few gallons of fuel, and drove it 3 hours home...through the worst thunderstorm I've ever seen.

Not a single malfunction, I'm happy to report.

Of course, now I have 3-4 years worth of very intense work to do!

Going to do some electrical repair first (don't have marker lights). Then, a compressor. Then, new air system. Then a clutch. Then, cosmetic stuff. But...it drives!

Yea!!!

Kent

Wow, I got it from both sides today. Feels like I got both barrels of rock salt out of a sawed off and looks like this deal's gonna go south before it even got started good.

I spoke to the grandson and wanted a face to face after work to make my offer. I hate talking on the telephone but he couldn't meet with me and just wanted me to make him an offer. I took my best shot and didn't even try to haggle. Gave him my top offer. He didn't seem too excited, which didn't surprise me since he really didn't seem too motivated to sell the truck in the first place. He mentioned something about the truck having a lot of sentimental value and he'd have to talk to his grandfather about it. Well we all know what that means.

The second blow came when I talked to the old man about it. He tells me it'll be a $5,000 truck after we fix it up and starts talking about patching the fender, putting tires and batteries on it, and whatever else it takes to get it road worthy. I tried to tell him I already had an out of state buyer lined up who wanted to restore it himself but I'm thinking now he's wanting to keep this one too like the last three I bought for us to fix up and resell.

When I told him I already had an out of state buyer lined up he asked me how I planned to get it to him. I told him I wasn't at that stage yet since I haven't even bought the truck yet so he starts figuring how much it would cost for one of his drivers to drive it to Marion, NC then fly back here to Alabama. I mean God love him he's one of a kind, mind always working on a plan.

Anyway, how was your day? Let's just hope the grandson agrees to sell and I'll get back to you when he does. The rest of it we'll worry about later if and when I get the truck.

Does anybody else have deals go like this?

Oh, I've had dozens of these deals fall through already!

I'm still not sure what I'm going to do tomorrow. I think the old girl would drive home fine. I mean, I've already driven it around their area long enough to have been half-way home! I'm just getting old and more easily scared, I guess! Just have these aweful feelings something's going to blow up over in the I40 river gorge!

I know the truck runs good, and everything works fine. But, it always will when you're within walking distance of the shop. Problems only show up when you're in "dark territory".

Know what I mean?

Old fashion ajusters look so.

The only fixing nut is at the end of the shaft.

But this one is of 1945.

Vlad

Actually, what I saw doesn' look anything like that. I'll check when I get home this evening; I MAY have a picture that shows one of the adjusters. I took several in that area, so MAYBE I got lucky and caught a glimpse of one!

Thanks,

More to come...

Kent

It is a bolt and when you remove it and the washer behind it the slack adj should slide off,to replace the bushings you will have to take the s cam out and to do that you have to remove the drums,I would leave the bushings till you replace the brake shoes..

Sounds like what it looks like. The other post, above, mentioned a fairly small bolt on a Mack-specific adjuster. But, as I said there, this hex is HUGE. It is almost as large as the shaft itself. Any way I can identify what we have here by looking? The adjuster collar/bolt looks exactly like the others I've seen, except for the lack of a snap-ring.

The older Macks had the Mack corporate brakes on them.

They used these at least through 1970 as far as my experience goes and again I'm used to single axles.

The Mack corporate brake used a 1/2" bolt to retain the slack adjuster along with a thick (hat shaped) washer that actually went part way into the slack adjuster.

These brakes are not what you're used to!

They do not have rollers in the shoes but instead use a flat wear plate.

They have square brake block rather than tapered brake block which is bolted on rather than riveted on.

The anchor pins are greaseable.

The "S" heads on the cams are a special contour an i believe the cams are 1-1/2" 10 spline.

I'm not trying to scare you, but I don't know what the parts availability would be or if they can be converted to a later style.

Ron

The hex I can see on the back of the slack adjusters is not a small hex, like you would associate with a 1/2" bolt. This hex is 1-1/4 - 1-1/2 inches across. Not sure if that tells you anything.

Oh, and I can give you an email address if you want to send more pictures.

Didn't get a chance to talk to the owner today but I'm guessing if my luck holds, two hot batteries and this one will fire right up like the last two I bought and if I get it for my price I can beat the $4K you're looking to pay for the other one.

Well, let me know what you can find out.

And, Thanks!

Kent

Check the bushings and seals on the cam shafts when you have it apart.

Excellent suggestion.

So, are these Mack adjusters as I described them, above? Or, are they still held on with the snap-ring? I didn't clean it up enough to see any details yesterday. I'm a little concerned about how much it might take to remove that lock-nut...if it is indeed a lock nut!

Hey, everybody.

Thinkin' real serious about the '70 R600 I found recently. Went and drove it today. More right than wrong with it.

Planning to re-do all the brake system anyway, if I get it. Brake linings have a bunch of life left. Adjusted the fronts up so it would actually stop bob-tailing. Rears were fairly close to being right.

Rear adjusters don't seem to want to co-operate. Some of the "collars" are frozen to the bolt. Others compress, but the bolt seems frozen. Checked prices. Not enough money to worry about. I'll just change them all.

Most I've seen use snap-ring to retain the adjuster. These Macks units seem to be retained by a BIG hex-head bolt. Is that how you remove them? I read somewhere the macks were 1.50" X 28 spline. Does that sound right?

I think, if I buy this, I'll start by replacing all the cans and slack adjusters...then the compressor...then all the lines. Then it needs a clutch. I just want to get my ducks in a row on these slack adjusters before I jump in over my head.

Kent

Not bad. The one I drove today isn't bad either, though. $4K, and I can drive this one home! Still trying to make up me feeble old mind...

Have you bought one yet? I'm may have one for you in Alabama if you haven't. Not sure if fits all your requirements but I think most have been met. Pretty sure it's a '68 R685 model. VIN is R685 T 3318. Let me know if you're still looking and I'll upload some photos.

Well, I'm zeroing in on one. But I could be swayed! Let me know what/where/how much/what condition. And, pictures are always nice!

I'm looking pretty seriously at one nearby. The condition is pretty good, and the price is right. But, I'd prefer to have a single-axle, as indicated by your VIN.

Kent

Kent, earlier you identified the clutch make/model. When I called the guys in Baltimore, they knew right away what I was talking about. They specialize in older clutches, but then again double plate spicers are pretty common, so anyone should be able to do it.....They fully rebuilt my single plate 15" Lipe-Brown clutch- new pads, rebuilt the complete assembly, and even spun-balanced it all. Now if I can just remember who the heck the place is.....I have it written down somewhere.....somewhere......lol

Thanks for that response. Good to hear that those numbers actually mena something to somebody!

Once I get this thing home (assuming the deal goes through), I'll be in a better spot to work on it. I'll probably be back in here to talk about it some more then.

Hey, maybe then I can post a picture of it in my profile.

Kent