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BucketTrucker688

1991 E7 350 engine brake intermittent at higher rpm's

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The Engine Brake on my 1991 E7 is cutting in and out at higher rpm's with a load on. Is this a sign of something? All the electrical connections look ok on the out side there seems to be a little oil seaping from the plug where the wires go into the head not bad but more than I'd care to see.

 

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My 95 does the same thing, I hear solenoids clicking in the glovebox when it does it. I'd like to know what's going on too.

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V-mac electronic engine controls started around 1990, whatchagot for injection pump? V-Mac one was 1990-1994. Last mechanical fuel pump went off-line on March 1, 1998. 

 

If it clicks in tandem with the cut-out you eliminated some of the possibilities. It is in the 85/86 circuit feeding the relay.

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My 1995 e7 350 is all mechanical. It does click when it's set to both heads. Rarely works on both heads, just on one. And it's pretty weak. So that's an intermittent power issue feeding the relay then?

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Run power to heads to confirm they are/are not   working. You can do it running. If they work chase the throttle/rack sensing ground circuit controlling engagement points. 

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Probably won't be able to look into it for a few weeks, I sub out for an oil delivery company in the winters, and we're starting a major overhaul on one of our concrete mixers. Jake brake is more of a toy than a necessity here. No mountain driving in our neck of the woods. But it has it so it should work!

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