Blue Ox

Thanks again fjh! According to the service manual I have the e7 valve springs had to be replaced with 190 t0 210# valve springs which is what the etech standard springs are in the book. I don't have the long down hill grades like out west so I may not have the same issues. I will try it if it works good if not I try a telma. 

I have everything to put the exhaust brake on. I can't find any reason it will cause major issues, like valves hitting pistons. I think I will try it, if I find any issues I will take it off.

Mack had the stealth brake that was both jake and exhaust brake from what  info I can find. I know of older macks with exhaust brakes and the guy who drove them said they worked fine.

Thanks for the warning! I found some oil in my air pipe so I am going to swap turbos before it fails maybe get one with the better seals. I can hold it with the jake and keep it at 1800. I really just want some extra, more braking the better.

Thanks for all the help. I can't find a reason not to use the brake.  I'm down for mud season so I have time to look around some more before I install it.

Just called pacbrake. They said they don't do anything with macks???? I am thinking the chart I found on they're site isn't much value.

Would there be another reason for them saying 20#?

My son in law works for ny state dot and says they run exhaust brakes on their macks. Going to try to find more info from them

From what I can find they are 1.573. I should have plenty of spring.

the service manual I have says valve springs are 190 to 210#. That is what is confusing. Why would pacbrake say 20#?

Others are 45 to 80#. The pre etech e7 is 45#.  I can't figure out why the etech would be so low. I have a jake on the truck and is working as good as expected, just looking to help it.

Pacbrake has a spring on it that controls the back pressure. I just found their application chart that lists the etech being limited to 20#. Don't think that will give much braking .

The telma will add about 700#. The maintenance is not bad, really just the bearings as far as I have found so far. The exhaust brake is simple enough, my concern is the back pressure. I have found one place that says the etech  is limited to 25# back pressure. I don't want to have the valves float and hit the piston. I am going to try pacbrake today and see what they say.

Thanks for the reply. I have been studying their site. I really like the idea of the telma, wish I could see one in operation. I am just weighing the cost of each. I think in the end I would be happier with the telma.

I am looking at a frame mounted one. I have a pacbrake off a c9 that is rated at 40# pressure. I found one place that said no more than 25# on an etech so I don't think I will use it.

I am thinking of putting an exhaust brake on my 2000 e7 460. I have been trying to find out what the maximum allowable exhaust back pressure is for my engine. I run 107000# and could use extra braking on hills. My other option I am considering is a telma retarder. I can find one from a mr688 and am wondering if anyone has installed one?

Thanks for the help. I got it adjusted and it is running  great.

I do appreciate the responses!

I deserve the response, I was ignorant. When I am stupid I admit it.

The plugs are still in place. I screwed up the valve adjustment will redo tomorrow, hopefully I didn't break anything. Like I said stupid mistake.

OK thanks I obviously made a stupid mistake. Not my first probably not my last!

I have the manual and the valve lash is .02 to.028 with the jake.

I have a 2000 ch613 with e7 460. The jake was dropping out so pulled the valve covers to check it out. I  found the exhaust valves had 1/4 inch lash. Adjusted them to .025 and tried to start it. The engine wouldn't fire. Backed the adjustment for the valves back closer to what they were before and it starts but sounds like the jake is on. I have had the truck for about 3 years and had not touched the engine before and don't have any past history on it. Any ideas on what the problem is?