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Topic: decelomatic mountain tamer (Read 598 times) previous topic - next topic

decelomatic mountain tamer

So I think I found out who made my mystery exhaust brake, Decelomatic Mountain Tamer.  No documentation with coach,  Gate valve design and air operated based on visual inspection.  Still acts/appears fully functional, and PO stated it was on there when he got it in 1995.  Has a morse cable operated lever like a shifter mounted to the left of the driver to vary the amount the valve closes. I have no idea what needs lubricated etc.
Old Phart Phred, EIEIO
89 GV ored 36' #3405 300 hp cat 3208 ATAAC side radiator, mountain tamer exhaust brake

Re: decelomatic mountain tamer

Reply #1 –
Quote from: Old phart phred –
I have no idea what needs lubricated etc.
Exhaust brakes are pretty simple.  Yours sound interesting - I have not encountered anyone else with a "manually positioned" brake.

As far as lubrication, the butterfly valve shaft is the main concern.  There is a special lube made by PacBrake - don't use any kind of regular oil or grease - it won't stand up to the heat.  See link for general info pertaining to lubricating exhaust brakes:

Maintenance | Pacbrake

http://www.xtremediesel.com/pacbrakec18037maintenancelube.aspx?gclid=EAIaIQobChMIrvfZg-GQ1QIVWBuBCh2_QgGSEAYYASABEgLwuvD_BwE

Try having someone operate the brake while you watch it - see if it moves freely in both directions.  If so, it is probably in good shape.  I would be curious to see how it controls the amount of back pressure produced.  When you close the brake at high RPM (where it is most effective), it could potentially raise the exhaust back pressure to a point where the exhaust valves will start to float - NOT GOOD.  In all the brakes I have seen or read about, there is some type of safety relief built into the assembly that will either prevent, or relieve, excessive back pressure.
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: decelomatic mountain tamer

Reply #2 –
Just a caution:  Make sure that back pressure when fully closed does not exceed the approved back pressure as determine by Caterpillar Corp.

Call Caterpillar with your engine serial number to determine that PSI: 877 777-3126.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: decelomatic mountain tamer

Reply #3 –
gate valve so shaft should very little exposure to exhaust stream, but cant see it.  Back pressure control is pure and simple, just a 1" bypass pipe around the valve connected to the exhaust pipe with welded on thread-o-lets with unions if you want to take it off to inspect and clean. morse cable operator just adjusts how far the valve closes. I guess if it hasn't floated the valves in 22 years (or more) the exhaust springs are ok.  Shaft would see high exhaust temp, but I did not see any way to lubricate the linear slide bearings. pneumatic actuator is stroked by solenoid valves at zero throttle or brake application.
Old Phart Phred, EIEIO
89 GV ored 36' #3405 300 hp cat 3208 ATAAC side radiator, mountain tamer exhaust brake

Re: decelomatic mountain tamer

Reply #4 –
OK...I just did a Google search on your brake, and some of the hits mentioned the sliding gate valve design.  I missed that in your original post - sorry.  My lubrication comment should be amended to read "lubricate the moving parts of the main gate valve".  I am still looking for a diagram or photo of the internal mechanism, just to satisfy my own curiosity.

Sounds like a pretty cool design!  Surprised it wasn't more successful. 
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"