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Truck Repair/fuel in oil - Cummins engine NTA 855


Hi Jeff!

The engine serial number is:


Looked up in cummins quickserve and they don't have anything on your particular engine. In my response before I would hand turn the engine after you make the adjustment to make sure nothing binds up. I think my biggest concern is the metal coming off that cam is going to cause a lot of wear in your bearings so if I had to do it I would get the new cam as soon as I could to not cause more damage in other areas of the engine. When you get it running with the new setting I think I would use a temp gun on the manifold where it exits the head that will give you a good indication if everything is firing ok your temps across all cylinders should be pretty close. Have anymore questions feel free to ask.

Was mulling this over some tonight are you sure the injector itself is not bad. I'm thinking that if the cam is worn that's not allowing the plunger in the injector to go down enough to allow all the fuel to exit the injector. so if my logic is right that would mean that your injector is continuously leaking into the cylinder. Wont fix your cam problem but would fix fuel leaking into the cylinder. Probably the best way to check is unhook the injector on each cylinder one at a time to see if the sound changes.

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Jeff Drumm


I Can answer any question pertaining to semi trucks and trailers. Have no experience in the automotive field so not able to help in that area.


My experiences in Semi Trucks is. I own my own truck and i presntly maintain a 80 truck fleet. Can handle any questions pertaining to a truck have tore apart and rebuilt every aspect on them. Fleet I deal with is Mainly Volvo trucks and a handful of freightliners. Work on automated transmissions on a daily basis along with carrier apu's. With engines my specialty is the 60 series Detroit but do work on the cummins isx the n-14 and the ism. and also the Volvo engines.

Have a College Degree from university of northwestern ohio in diesel and agriculture mechanics. Have 10 years behind the wheel driving a truck and 4 years working on trucks full time. Also have grown up on a farm so have been tinkering on trucks and tractors all my life.

Awards and Honors
I've gone through online schooling and have received certificates from webb wheel, Timken and Volvo academy.

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