Helix 2 cam = no exhaust brake ??

[ENafziger]

Quick question...

After the install of the Helix 2 camshaft, the Jacobs exhaust brake no longer has any braking power at all. Is this the result of the camswap? I've read hours upon hours of material before purchasing the cam, and don't remember anything being discussed regarding exhaust brakes.

I've checked the electrical connections, verified vacuum to the pod, and verified the linkage was working on the elbow. I even removed the exhaust right past the elbow so I could see the butterfly valve closing and opening as the brake was applied... and everything appears to be operational.

However, since the camswap, you can't even hear the exhaust brake come on at all. It provides absolutely no braking power. Prior to the camswap, I could be driving at 60 mph in 5th, and down shift to 4th so quick that the exhaust brake kicking would cause the 37" tires to chirp!

Thoughts?

--Eric
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[SRadke]

It isn't the cam. Mine works fine. The pump is the obvious part of the brake that would be disturbed in the cam install process. Is it making the vacuum it should be?

-Scott

 

[SRadke]

Have you checked back pressure in the exhaust manifold? Should be 60psi at redline with the brake engaged.

 

[ENafziger]

Is it making the vacuum it should be?

It is making vacuum. I got a gauge that I'll be installing to get a reading on backpressure.

Thanks, Eric

 

[jelag]

Exhaust leaks at the Turbo/exhaust brake is the most common cause of poor performance... Low vacuum or low air pressure, based on your system is the 2nd most common cause... .

All of our old Fords had a vacuum pump that ran the exhaust brake like the older dodges... we used to give the pump a table spoon of oil every year to lube the parts and clean the dirt out... . we'd pull the vacuum line from the exhaust brake and let it suck up a table spoon of 30 wt oil... you can't believe how clean oil can be so dirty in 30 seconds when it spits out the vent of the pump.....

Hope this helps...