You are here:

Truck Repair/M11 timing


QUESTION: running overhead on M11 that previous tech screwed up accessory drive timing marks in relation to setting overhead. How do I get back to square one?

ANSWER: Can the motor still roll over by hand or does it get stuck. If your on A with cylinder #1 are valves loose or tight. What are #6 valves like on A #1 just trying to get a better idea where to go to. I've had a similar experience on a isx by accident but I caught my mistake when I adjusted the wrong cylinder I couldn't roll the engine to the next setting because the wrong adjustment would bottom out in the valve train and not let the cam roll over the hump. In that case I backed it up to the previous mark I adjusted and backed off the valves and injector and started from the beginning again to cover myself. If you can give me some more details how things feel I can be of some more help to you.

---------- FOLLOW-UP ----------

QUESTION: well, it felt as if number 1 was ready, as both valves were closed and number 6 exhaust was tight. I was on A, and as I set intake/exhaust then Injector to proper setting, went to roll engine and it was stuck to the point that I knew something was wrong. previous tech replace accessory drive, but I don't think timing was taken into consideration. Not really sure if my A, B, C marks are correct. I am aware of the viewing hole on the front cover to check cam marks, but not really sure about how to correct this mess. Sorry for the delay in response, left for dinner. back on it now.

Well definitely would start by backing those settings off on #1 that you made. then I would check that the timing marks through the front view hole are right. then you should be able to proceed with running the overhead like you were. the only way that a,b,c can be off is if the timing marks on the gears are off the front pulley has a woodruff key on it so it can only be put on one way unless that woodruff key was left out. Now if he didn't set the time on those gears and you back off #1 and it still feels like its getting stuck when you roll it I would probably loosen the bolts on your rocker shaft hold downs so you can get that timing right.

Truck Repair

All Answers

Ask Experts


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.

©2016 All rights reserved.