DieselTalk

DieselEngineTrader's FREE Diesel Engine Forums

new topic search Categories login View Caterpillar Engines

CATEGORY LISTINGS > CATERPILLAR > c-15 acert engine brake

[ REFRESH ]

Thread Title:

c-15 acert engine brake

Created On Saturday January 16, 2010 09:52

pete379

Posts: 14
Joined: Nov 2008

Saturday January 16, 2010 09:52
C-15 acert s/n nxs 75000 miles When engine brake cuts off at 1000 rpm or using pedal the engine brake comes back on for just a second or two and then stays off. Local cat dealer can't find what is causing problem. Anyone have any ideas.

Quote

Top

Bottom

TDcrash63

Posts: 163
Joined: Sep 2007

Saturday January 16, 2010 10:04
Brakes most likely have broken or sagged out springs. Put a tune up kit in it. If that all looks ok I would throw 3 solinoids in.

Quote

Top

Bottom

pete379

Posts: 14
Joined: Nov 2008

Saturday January 16, 2010 10:33
Just had overhead ran at 57000 miles, probelm started at new. Wouldn't Cat noticed that doing the overhead?

Quote

Top

Bottom

TDcrash63

Posts: 163
Joined: Sep 2007

Saturday January 16, 2010 22:01

If the problem has been there since new and the engine still has failrly low miles. Tune up kits probably wont solve anything. Assuming the adjustment is correct. I think it is probably a solinoid but the only way I can think of to verify that would be to buy one then swap them out one at a time. Remember also that low is the middle head. Medium is the front and rear heads and high is all three. Try operating it on low and med to see if you can narrow it down to the middle only or one of the end heads.

Quote

Top

Bottom

pete379

Posts: 14
Joined: Nov 2008

Sunday January 17, 2010 07:35
I have tried it in low med and high it does in all three.

Quote

Top

Bottom

pete379

Posts: 14
Joined: Nov 2008

Sunday January 17, 2010 09:02
If a solinoid is bad could it cause problems even if the engine brake is off? The engine sometime stumbles like the brake is come on when shifting. Even at highway speed it feels like one trying come on.

Quote

Top

Bottom

TDcrash63

Posts: 163
Joined: Sep 2007

Sunday January 17, 2010 15:44

If it does it in low [the middle head] as well as med [the outer heads] I have to wonder about adjustment, possibly set incorrectly. Or maybe, I do not know what, its something besides the Exhast brake, possibly a V V A hanging up, Although that will usually trigger a diagnostic code. The solinoid is the gate for the oil to pass into the head and push the triggers out, as the exhast brake fills with oil. When the engine camshaft pushes the injector arm down. The back of the arm pushes the trigger into the head. This pushes the foot out onto the valve bridge causing that cylinder to dump its cylinder pressure out the exhaust. When the solinoid is disenguaged it opens a dump port below it. The springs in the head on the triggers raise them back into the head pushing the extra oil out. This happens in a millisecond. They cannot come on with out oil. The solinoid turns on or off the oil. The V V A heads work in a similar fashion. But the do not have a trigger. They are fired only by the Ecm. I have only seen one stick. It was on all the time and triggered a fault code. But it did sound very similar to a Jake sticking. The C-15 non acert and 3406 engine would quite often escpecially when cold. Hang up the Jake Brakes. You would fire them in the shop when the engine came down to idle they would stop then pop again real quick. Replacing the solinoid usually solved this problem.

Quote

Top

Bottom

westcoast

Posts: 982
Joined: Dec 2008

Wednesday January 20, 2010 06:51
If it,s popping out the intake you,ve got a vva sticking /moving / broken stud - if it,s popping out the exhaust on all settings you,ve got a weak or broken regulator spring / clutch switch / brake switch or tps playing up Regards David ------------------------- detroit