Community Forums

Rich-n-Linda · 02-13-2016, 06:25 PM

Quote:

Originally Posted by DMTTRANSPORT

FYI, the single stage engine brake has the same amount of hold back power as the three stage....think!

No it doesn't. Not even close.

A single stage exhaust brake does not have anywhere near the braking power of a Jake Brake (compression brake.) I have a 2-stage Jake on the ISL in my coach and I never have to use the service brakes on interstate grades. On a 6% grade I often have to switch back and forth between LOW and HIGH because in the high position it slows me down too much.

jarwiebe · 02-13-2016, 07:15 PM

Quote:
Originally Posted by DMTTRANSPORT View Post
FYI, the single stage engine brake has the same amount of hold back power as the three stage....think!

Quote:

Originally Posted by Rich-n-Linda

No it doesn't. Not even close.

A single stage exhaust

brake does not have anywhere near the braking power of a Jake Brake (compression brake.) I have a 2-stage Jake on the ISL in my coach and I never have to use the service brakes on interstate grades. On a 6% grade I often have to switch back and forth between LOW and HIGH because in the high position it slows me down too much.

Crasher · 02-13-2016, 09:03 PM

It's great that the op has asked this question. However it re-enforces my belief that before anyone, with a few exceptions, can legally drive a complex diesel motor home, should be required to take a driving course along with an educational class to learn the safe way to drive and maintain one. When I was younger, I had to pass an exam to drive a school bus. Then I had to get a CDL license to drive our semi and crane trucks, I also had to get an endorsement to ride a motorcycle. Yet, a person who may have never driven anything heavier than a pickup truck can walk in and buy a complex 30 to 40,000# diesel pusher and drive off into the sunset with little or no experience of how to deal with many different potentially dangerous situations that can happen to any of us.

Tell me where I'm wrong.

Ray,IN · 02-13-2016, 10:04 PM

Quote:

Originally Posted by Crasher

It's great that the op has asked this question. However it re-enforces my belief that before anyone, with a few exceptions, can legally drive a complex diesel motor home, should be required to take a driving course along with an educational class to learn the safe way to drive and maintain one. When I was younger, I had to pass an exam to drive a school bus. Then I had to get a CDL license to drive our semi and crane trucks, I also had to get an endorsement to ride a motorcycle. Yet, a person who may have never driven anything heavier than a pickup truck can walk in and buy a complex 30 to 40,000# diesel pusher and drive off into the sunset with little or no experience of how to deal with many different potentially dangerous situations that can happen to any of us.

Tell me where I'm wrong.

No-one can challenge that opinion.

jwmaustin · 02-14-2016, 05:26 AM

You know I can't challenge that and have always said the same thing. But I'm wondering why we don't hear of more accidents and have more issues with the high cost of insurance as we get older...

mel s · 02-14-2016, 07:17 AM

Quote:

Originally Posted by ;2938867

FYI, the single stage engine brake has the same amount of hold back power as the three stage....think!

DMTTRANSPORT
You are correct.

When a "3 stage compression release engine brake", (frequently called a "Jake brake" or "Jacobs brake"), is set to "3" it has the SAME amount of hold back power as a "single stage compression release engine brake".

However when set to "2" a 3 stage has LESS hold back power than a single stage... (even less when set to "1").

Mel
'96 Safari

DMTTRANSPORT · 02-14-2016, 07:24 AM

Quote:

Originally Posted by mel s

DMTTRANSPORT
You are correct.

When a "3 stage compression release engine brake", (frequently called a "Jake brake" or "Jacobs brake"), is set to "3" it has the SAME amount of hold back power as a "single stage compression release engine brake".

However when set to "2" a 3 stage has LESS hold back power than a single stage... (even less when set to "1").

Mel
'96 Safari

Thanks Mel, I gave him the chance to THINK, but......

DMTTRANSPORT · 02-14-2016, 07:31 AM

Quote:

Originally Posted by Rich-n-Linda

No it doesn't. Not even close.

A single stage exhaust brake does not have anywhere near the braking power of a Jake Brake (compression brake.) I have a 2-stage Jake on the ISL in my coach and I never have to use the service brakes on interstate grades. On a 6% grade I often have to switch back and forth between LOW and HIGH because in the high position it slows me down too much.

Sorry, a single stage engine brake offers "on-off" which means you cannot select 2 cylinders, 4 cylinders or all 6, it offers all 6 only, yours offers 3 cylinders or 6 cylinders, single stage is the same as yours with out the de rate of other cylinders.....

Tony Lee · 02-14-2016, 09:34 AM

Quote:

Originally Posted by Rich-n-Linda

No it doesn't. Not even close.

A single stage exhaust brake does not have anywhere near the braking power of a Jake Brake (compression brake.) I have a 2-stage Jake on the ISL in my coach and I never have to use the service brakes on interstate grades. On a 6% grade I often have to switch back and forth between LOW and HIGH because in the high position it slows me down too much.

He is correct 100%. He clearly wrote "engine brake" and it is true that the maximum braking for a single stage is the same as the maximum from a three-stage

DMTTRANSPORT · 02-14-2016, 10:24 AM

Quote:

Originally Posted by Tony Lee

He is correct 100%. He clearly wrote "engine brake" and it is true that the maximum braking for a single stage is the same as the maximum from a three-stage

LOL, yes he is correct if the Engine brake is not operating correctly and the only available jake is the 2 cylinders on the 1st/single stage (3 stage) or 3 cylinders on a (2 stage), I stand corrected.

The reality of the issue is stated above though.

96 Wideglide · 02-14-2016, 02:17 PM

Quote:

Originally Posted by -Gramps-

Here is some really good info as to how to handle mountain driving:

https://www.fmca.com/motorhome/motor...-the-work.html

Interesting, but not a method I want to use. I'm not going to let my rpm's get so high the tranny upshifts to protect the engine, over, and over, and over

!!

firedoc · 02-14-2016, 02:57 PM

Quote:

Originally Posted by RayBH

I am surprised in this discussion that there are several references to risks of overheating of the brakes but no mention of running low on air supply by frequent applications of the brakes.

When I took the air brakes course, the instructor stressed holding a steady pressure on the brakes (as DMTTRANSPORT mentioned) as opposed to frequent short brake applications to control the speed, since each application and release eats up air supply. He maintained that the brakes will not overheat if a steady pressure is used to keep the speed under control.

I think paying attention to one's air supply should also be mentioned in this discussion.

The instructor at your air brakes course in dangerous. He needs to quit!!!

DMTTRANSPORT · 02-14-2016, 04:02 PM

Quote:

Originally Posted by firedoc

The instructor at your air brakes course in dangerous. He needs to quit!!!

He needs to quit for the reason that you don't agree with his technique of descending down a grade, or, mine for that matter? I feel you should sell your Coach for the reason that you do not know the correct way and you could kill someone, get down the hill what ever way you are comfortable with.....geeeeze!

BRex45 · 02-14-2016, 04:06 PM

The danger here is taking our mostly anecdotal knowledge and re-distributing it as some type of fact. Internet experts can get you killed. It's also apparent the concept of exhaust brakes as compared to engine brakes is not totally grasped here on iRV2

OTOH:

The first-hand experience of our long term pusher drivers and our members who have commercial driving and mechanical experience
is invaluable to us. We CAN learn from them.

Approach all downhill stretches carefully😐😐😐