Can I convert to regular brake chambers from Rotochambers?

belfert · September 13, 2011, 07:21:19 AM

My understanding (which may be incorrect) is that all chambers need to be either long stroke or short stroke. It seems I would probably have to retrofit the entire bus if I wanted to go to long stroke. My bus is currently at the shop getting the brakes inspected from top to bottom. If they determine any more chambers need to replaced I'll need to see what they say about switching to normal chambers instead of rotochambers.

Bryce has determined the spring brake chambers on his Dina are type 3636 so I would assume mine are too, but the only real way to know would be to look at what I have.

belfert · September 13, 2011, 07:28:02 PM

The shop said one of my tag axle brake chambers is bad. I talked to them about it and they are going to replace the brake chambers on both sides with regular type 16 brake chambers instead of type 16 rotochambers. I can't go to long stroke without replacing the chambers all the way around.

The labor to swap the chambers and the chambers themselves should be the same or less than just one rotochamber.

buswarrior · September 13, 2011, 09:48:55 PM

Hold the phone.

You don't have to retrofit the entire the vehicle if choosing to upgrade to long stroke chambers.

Good form is to have symmetry on each axle.

So, upgrade an axle at a time, as you need or want to.

With the T16, a long stroke will give you a safe push rod stroke of 2"
the standard chamber is only good for 1 3/4".

happy coaching!
buswarrior

belfert · September 14, 2011, 06:51:32 AM

Here is what I found online regarding long stroke and short stroke chambers on the same vehicle:

"All VENDORS advise to never install long stroke and standard stroke chambers on the
same vehicle. This can cause poor brake balance and timing."

Is that statement incorrect? It does sound like long stroke is the way to go. I suspect the shop may have already installed the short stroke chambers last night on the second shift.

buswarrior · September 14, 2011, 07:08:38 PM

What is the source, and how old/new is it?

I am open to new learning, and am very curious as to the justifications for the statement.

happy coaching!
buswarrior

belfert · September 15, 2011, 06:29:20 AM

I took that quote from http://www.newlifeparts.com/catalog/section3.pdf

The shop that is installing the chambers also said that long and short stroke chambers should not be mixed. I would need to replace all the chambers to go to long stroke.

bevans6 · September 15, 2011, 06:41:53 AM

I think it's a CYA statement on the part of the manufacturer. If stroke adjustment is maintained the same on all the chambers, there will be no issue with timing. If some chambers that are short stroke are adjusted real short, but the long stroke chambers are left to go to the limit, yeah I can see a timing issue. I don't know of any regulation regarding this, and I know that my air brake course addressed this and warned us to look for long stroke chambers when checking brake stroke.

All the same, if you were to be changing all the chambers anyway, long stroke is a useful upgrade if they fit. I plan to go to long stroke chambers on the front axle of my bus when I change them. DD3 are already long stroke chambers.

Brian

belfert · September 15, 2011, 09:16:20 AM

I am not going to be replacing all of the chambers at this time. If the other rotochamber on the front needs replacement I will consider redoing everything with long stroke chambers. I won't lose all that much money replacing the type 16 chambers on the tag axle again.

buswarrior · September 16, 2011, 07:08:25 AM

Thank you belfert,

That appears to be a vendor's made-up introduction above the regular manufacturer's catalog information.

Too casual and too vague in certain respects of the wording. And the "performance improvements" are presented out of context, typical of a sales brochure, not an engineering paper.

I'll suggest it is a less than credible source for our decision about retrofitting.

My guess is that the vendor, out of self interest, is trying to prevent the reverse, that is, buying the less expensive standard chambers as retrofits for a long stroke equipped vehicle, which was/is happening. Profit margin is the driver.

If mixing chambers on the whole vehicle was an issue, I'd be very surprised that Bendix or one of the government safety groups would not have already written a paper and it be widely disseminated in the trade press. And, in doing so, become common knowledge.

That is not to say that the book is closed, just that we can't find any more pages.

So, since axle symmetry, versus whole vehicle, has been advocated from many of the credible sources, I guess we'll still go with that.

Keep your money in your pocket!

happy coaching!
buswarrior

belfert · September 16, 2011, 07:25:19 AM

I can't believe somebody would be so tight in the wallet as to replace long stroke chambers with short stroke. I did a little bit of checking and found that long stroke chambers are only about $10 extra. I found a Leland type 24 long stroke for $23.95. It was even less than the short stroke from Velvac. A spring brake chamber is about $20 extra.

buswarrior · September 16, 2011, 07:28:45 AM

They are closer in price now, that was not the case a decade ago.

Most of this stuff just keeps in lingering, long after the relevance has subsided.

And, $10 is $10. You wouldn't believe what gets done to keep a nearing bankruptcy truck on the road.

Or a busnut?

happy coaching!
buswarrior

belfert · September 17, 2011, 09:06:33 AM

I just got my bus back home with the new chambers installed on the tag axle. Total cost including parts and labor was about $200 less than just the rotochamber alone not including labor. I wish I would have understood why the front brake chamber cost so much at the time. I could have had new chambers on both front wheels and saved at least $300. Sometimes an education costs a few bucks.

luvrbus · September 17, 2011, 09:30:15 AM

Now I would call a rebuilder like Kirk's and sell him the Roto chambers for a core,I am happy for you that it worked out I bet it stops just as good lol

good luck

belfert · September 17, 2011, 10:38:18 AM

Clifford, you reminded me they didn't give me back the good rotochamber like they said they would. I'll have to call on Monday. I do have the bad rotochamber from the front. I might eventually find someone who wants the good rotochamber.

belfert · September 30, 2025, 02:13:21 PM

This newer Dina I want to buy I am also having issues with the rotochambers. One of the front brake chambers has a bad diaphragm. The mechanic working on it wanted to try and find a diaphragm. I told him he would likely have a heck of a time finding a diaphragm. I asked him to just replace the brake chambers on both sides with standard chambers.

I am pretty sure the fronts are type 24, but I will double check my bus when I get home.