Exhaust Valve Springs

[pwhittle]

I am considering upgrading my PacBrake and have a recently installed remanufactured head with standard exhaust valve springs that will support 30 lbs backpressure.

I am considering switching out the exhaust valve springs to support 60 lbs back pressure for improved braking.

Has anyone done this themselves?

Motorhome is a 1994 Monaco Crown Royale Signature with CTA8.3 engine.

Thanks in advance

[J Walker]

I would call PacBrake to find out if the springs on the remanufactured head are sufficient. You seem to need more from your exhaust brake and there are other things to check such as the PacBrake itself and the exhaust valve. I have not heard of special springs being needed for an exhaust brake.

[Mekanic]

I don't just swapping springs is going to make any difference in braking performance.
Also I'd stick with what ever the limmit that cummins says is ok.
If you get more back pressure PSI in the exh than you have oil pressure in the turbo you could damage the seals in the turbo.
Like the poster above I'd ask the company that makes the exh brake.

[pwhittle]

I did speak to Cummins before I posted. They said standard springs support 30lbs but that stronger one are available. If you have more back pressure than the springs are designed for, the exhaust valves can float and interfere with the pistons.

It is not the springs alone that help. It is the ability to put more back pressure using the PacBrake.

Back to the original question: has anyone done this themselves?

Paul

[Skip426]

Paul, I worked at a Dodge/Cummins shop for 34 years, installed many Pac Brakes and replaced the springs in about a dozen 5.9, 12 valve engines. If you have replaced valve seals in a gas engine yourself, replacing the exhaust valve springs in a Cummins engine should not be a problem. Usually takes longer to adjust the valves when you are finished than to change the springs. Just make sure there is no way to drop a valve keeper through to the oil pan. (DON"T ASK ) A question though, is the Pac Brake your considering, up-gradeable to the higher back pressure. In pick ups the high pressure unit was recomended for manual trans , heavy trailer applications only. Check with Pac Brake on this .
If you do go ahead, before you remove any springs from the engine , make sure the valve spring compressor your using is stong enough to handle the new springs.
Hope this helps. Good Luck.

[pwhittle]

Thanks for posting Skip.

I was able to take the old PAC-Brake off and lube it up to get it operational so I am good for now.

I will use your guidance when I have to upgrade.

Paul