Air compressor knock

[Platinumpete]

2014 pete cm 2350 350k on engine. Knock coming from drivers side front of engine sounds like compressor. Pretty loud till engine warms up then gets quieter. Had front pulleys checked and overhead run to eleminate those issues. Any ideas?

[Rawze]

It could also be the fuel pump.

[Waterloo]

(07-23-2017 )Platinumpete Wrote:  2014 pete cm 2350 350k on engine. Knock coming from drivers side front of engine sounds like compressor. Pretty loud till engine warms up then gets quieter. Had front pulleys checked and overhead run to eleminate those issues. Any ideas?

Rawze pointed to the fuel pump... You do know about the fuel pumps on your particular motor blowing apart and essentially creating a boat anchor under your hood? Eats the crank shaft and all of that stuff? Pull the oil and fuel filters and check for metal, carve those suckers apart. If the filters are clean, no metal, it may be soot build up in your air compressor head. I don't know if your particular air compressor is like the one on my CM-871, if it is, there should be a head rebuild kit for it. The air compressors on the cummins are about the only good engineering they have going for them. New air compressor head and gasket kit runs around $500 and normally solves the knock. Pray it is the air compressor. ;-)

[Platinumpete]

(07-23-2017 )Rawze Wrote:  It could also be the fuel pump.

Been doing it for over a month I don't think fuel pump would have lasted that long planning on rebuilding at 400k

[Hammerhead]

(07-24-2017 )Platinumpete Wrote:  Been doing it for over a month I don't think fuel pump would have lasted that long planning on rebuilding at 400k

At 350k, you're certainly close enough in mileage to warrant an inspection. I wouldn't even consider playing the "wait n see" game with the hand grenade that an XPI fuel pump is...
The cost of the gaskets and the barrel/plunged kits to check it or do it early is a pittance compared to a replacement motor.

[Waterloo]

(07-24-2017 )Hammerhead Wrote:  

(07-24-2017 )Platinumpete Wrote:  Been doing it for over a month I don't think fuel pump would have lasted that long planning on rebuilding at 400k

At 350k, you're certainly close enough in mileage to warrant an inspection. I wouldn't even consider playing the "wait n see" game with the hand grenade that an XPI fuel pump is...
The cost of the gaskets and the barrel/plunged kits to check it or do it early is a pittance compared to a replacement motor.

I was just up at the dealer, they had a low mileage 2250 or 2350 in a crate, doesn't matter, BOAT ANCHOR. Fuel pump, destroyed the crank and all points in between.

[Hammerhead]

(07-24-2017 )Waterloo Wrote:  I was just up at the dealer, they had a low mileage 2250 or 2350 in a crate, doesn't matter, BOAT ANCHOR. Fuel pump, destroyed the crank and all points in between.

I'm not sure which part more sad Waterloo;
1) the fact that the fuel pumps destroy these motors so prematurely
...or...
2) that no matter how much you warn guys, and even show them the testimonials, they won't believe or listen to you

[Rawze]

(07-24-2017 )Hammerhead Wrote:  I'm not sure which part more sad Waterloo;
1) the fact that the fuel pumps destroy these motors so prematurely
...or...
2) that no matter how much you warn guys, and even show them the testimonials, they won't believe or listen to you

It is the old case of "I never though it would happen to me".

[Platinumpete]

Shouldn't I get a low fuel rail pressure code if pump was failing.