Interesting, In a tug boat that same diesel engine would transmit torque through the shaft via reduction but would not have the multiplier. In it's simplest other form on a bicycle torque is produced, ie., multiplied or reduced by a front chainring driving a variety of smaller gears on the axle of the rear wheel. Full overdrive on a bicycle is achieved when in the largest chainring on the front (crank) and the smallest cog on the rear wheel axle.
Engine Braking
- Thread starter ChinMusic
- Start date
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Laura & Charles
Well-known member
I have the engine brake on all the time on level 3. (It has three settings, level 1–for two cylinders, level 2– four cylinders, and level 3–for all six cylinders.) “Why?” is because when I let off the throttle, it is just coasting… it is like if you shift a gas engine to neutral. Do that every time you come to a stop and you’re going to be going through brakes like crazy. Rosie clocks in at about 43,000 lbs (by herself… with the toad, even more, but it’s got its own brakes); I want all the help taking her speed down that I can get, even on flat terrain.)
I DO adjust it to a lower setting or turn it off if conditions warrant it.. but, for the most part, it’s always on.
I drive with my gasser in T/H all the time now, regardless towing or not, but before I always switched to T/H in urban areas for the engine braking.
Larry N.
Well-known member
On my Beaver I couldn't do that because when the brake was on it disengaged the cruise control, but the VGT on my Ventana I always left on, except in rare circumstances where I might want to coast. But the Beaver one (true compression brake) was loud, even in the cab, though extremely effective. The VGT in the Ventana was hardly audible beyond normal engine noise.
Tulecreeper
Well-known member
In my little burg, the sign is right at the same spot as the MPH dropping from 55 to 45, and there is a slight downhill at the same time but it's only for about 50 yards then it flattens out again. My question is still, "Why would a rig have its engine brake engaged at all anywhere in my geographical location as there are no grades worth mentioning that are steep enough or long enough to need it?"
I drove dump trucks and hauled heavy equipment all over the N. CA area for years and the only times I engaged mine was when I was in the mountains where I had sometimes stretches of single-lane hwy/road with a 7% grade or more that lasted for several miles. That's when I needed it. The little whoopty hills here and there that weren't more than 100 yards long didn't warrant it, no matter how steep the grade.
Because it’s loud.
Tulecreeper
Well-known member
Are you saying you think the truckers do it to impress someone with the noise? I don't know any truckers that would do that. The engine brake is a tool to be used when necessary, like air conditioning.
Maybe because that’s where the town ‘s jurisdiction begins and/or that’s where traffic lights are located and where loud Jake brakes are likely to be a public nuisance.
Skookum
Well-known member
- Joined
- Dec 19, 2018
- Posts
- 3,664
I drove dump trucks too. One day, the back pressure blew a hole in the exhaust before the muffler, it was an old Mack RD600 and the exhaust was original. The hole blew right where water settles from the vertical pipe up the right side of the cab. Oh man, that was fun, thundering bah-buh-bah-buh-ba-buh!!! coming to a stop. When you weigh 105,000 lbs you try to use the Jake whenever possible, otherwise you're wearing brakes on 7/8 axles. I wrote it up and the shop had it fixed by the morning.
yeah ....its not the engine brake system that load...but rather the moron trucker with gutted 8"-9" straight exhaust stacks.
Drive beside a new class 8 tractor with OEM exhaust stacks has very little noise with the engine brake.
Exhaust brakes on my Cummins is just a slight hiss out of the tail pipe.
Grain haulers/cattle haulers and independent owners are the worse with gutted exhausts/racket around here anywayz.
Drive beside a new class 8 tractor with OEM exhaust stacks has very little noise with the engine brake.
Exhaust brakes on my Cummins is just a slight hiss out of the tail pipe.
Grain haulers/cattle haulers and independent owners are the worse with gutted exhausts/racket around here anywayz.
Yep, back in the 90’s those dudes would come blasting down through Jaspar, Ala. in an owner/operator PB with a load of coal and when they hit that brake it would shake your windows. The town finally enacted the brake ordinance and brought peace to the valley.
Larry N.
Well-known member
Which is a long ways from compression brakes (aka Jake Brake), in both effectiveness and in noise. BTW, what rig is that Cummins in?
But these ordinances were generally set up way back before the new class 8 rigs with their newer muffling tech, and even today the engine compression (Jake) brakes are louder than exhaust brakes. The 2007 Beaver I had with a compression brake was OEM and was indeed very loud when the brake was on (as I've mentioned before) with its CAT C-13 engine -- nothing to do with "gutted 8"-9" straight exhaust stacks" at all.
Laura & Charles
Well-known member
What year was your Beaver? Monaco owned both Beaver and Holiday Rambler for a while. On ours, it’s the opposite. With both engine brake and cruise control on, the engine brake doesn’t engage until you cancel the cruise. (And even just pressing on the accelerator cancels the engine brake.)
Larry N.
Well-known member
It was a 2007, built in 2006. Is your HR using a Cummins engine? I suspect it's the difference between a CAT engine (C-13) and a Cummins, if so. Is it a compression brake or exhaust? That might be a big difference.
With both my Beaver and with the Ventana, stepping on the go pedal stopped the actual braking, but didn't turn it off, such that when you let off of the pedal it would re-engage the braking.
jymbee
Well-known member
Hills are just one scenario. Engine braking is also used any time to reduce speed. Entering a town with reduced speed limits, coming up to a stop sign, slowing down to make a turn, catching up too fast to a vehicle ahead etc etc.
CharlesinGA
Well-known member
Engine braking is free, brakes are not!
Charles
Charles
Laura & Charles
Well-known member
Mine is a three stage compression brake. If cruise control is off, it works as you describe, off if foot on go pedal, on as soon as I let off.
It was made in those few years when Navistar owned the group and the engine is a Navistar MaxxForce 10. It gets a lot of negative commentary on the forums, but I’ve found it to be an ok power plant. It’s kinda cool to have a 2012 engine that doesn’t need DEF.
Gary RV_Wizard
Site Team
I think every profession has its share of ass-hats. If you've never met any, consider yourself lucky.
It only takes a few occurrences to motivate the town council to make a noise ordinance & post a sign, and the ordinance & sign remains even if the problem has since faded away.
OP
OP
ChinMusic
Well-known member
I’m getting the idea the sign is mostly to remind the “honest” that there are houses nearby and be respectful.
I now understand that my Allison Retarder has nothing to do with such ordinances unless some dishonest LEO is playing games.
I forgot that my son-in-law works for Allison in Indy and got his opinion on leaving the Retarder on. He felt that it’s pretty bulletproof.
Tulecreeper
Well-known member
In my little burg there are no residences within several blocks of where the sign is placed, and those are off to the side across the creek and through the woods. From where that sign is placed next to the 45 MPH sign and city limit sign, all the way through "town" past the lumber mill and to the other city limit sign is about a mile. The only things along there are the lumber mill, a Sonic Burger, a Subway, a small grocery store, and a small pharmacy. Then you're out of town again and back to 55 MPH.
