How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Cat Man Your Own Question
Cat Man
Cat Man, Cat Engine Expert
Category: Medium and Heavy Trucks
Satisfied Customers: 8810
Experience:  I am ASE Master Truck Certified.
Type Your Medium and Heavy Trucks Question Here...
Cat Man is online now
A new question is answered every 9 seconds

I have a 2000 c-15 6nz with 700000 on it. Last week the engine

Customer Question

I have a 2000 c-15 6nz with 700000 on it. Last week the engine started running really rough and was blowing air back though the air cleaners on my w-900. I took it to a shop in Canada and they diagnosed the #1 hole was not firing. After removing the valve pan cover they discovered the cam shaft is worn and the first rocker arm was pitted. They of course came back with a $35k inframe. I was under a load and just kept on trucking. The next day the engine stopped missing 90% and seemed to be running fine. I realize the cam needs replacing however I am scheduled with loads for another 6000 miles. The engine developed another noise however. when building up speed between 1300 and 1500 rpm the engine is making the same noise as it does when I am jaking. It seems to get worse then gets a little better. I stopped using the jake today now when I try to use it its not nearly as strong as it was yesterday. I am on the road working and shops want to take me down for a week. Gotta keep rolling. I am now thinking its the jake causing the engine missing etc.
Submitted: 2 years ago.
Category: Medium and Heavy Trucks
Expert:  Cat Man replied 2 years ago.
Hi. Thanks for asking your question and requesting me. I will try and help you out.
Yes I 100% agree. It sounds like a jake problem. It's most likely sticking or hanging. I have seen this before. Jakes can hang and miss and run rough then stop. If it were an injector or cylinder problem. It would not stop.
Please reply back if you need more help or have more questions. I am happy to assist.
Customer: replied 2 years ago.
How can I fix it? Would a sticky jake be holding the valves down at tdc making the rockers excessively loose. Because they were very loose. I tightened them a halve a turn to take out the slack.
Expert:  Cat Man replied 2 years ago.
The jake would need to be rebuilt or replaced. I am sorry. I wish I had better news.
The rockers will be loose. They are not suppose to be tight. Be careful tightening them up. A feeler gauge is used to set the gap on all the rockers and Jakes.
Customer: replied 2 years ago.
I understand how to set the gap. They were loose, I think, because of the excessive wear on the cam lobe and the deteriorating roller on #1 intake valve which is the root of my problem. While the jake is the current frustrating problem I think it to is stemming from the cam throwing everything out of adjustment. I backed the jake off the number one hole a turn and it seems to be helping. If I can get over to salt lake city I have a buddy with the tools to replace the rocker arm which will help me get my last trip in. I haul loads to Fairbanks and everything is scheduled in advance and I just need to get another week out of it engine then I can schedule it for maintenance. The truck is still working and it will run rough until it dies, but If you have been working on cats for thirty years and you think about this problem you would advise me what to do to get the truck out of the woods and buy me a little time. Thanks
Expert:  Cat Man replied 2 years ago.
Thanks for the information.
Sounds like a plan. If it is running better that's good news. You should be able to make to salt lake. Then you can get the repairs in
Please reply back if you need more help or have more questions. I am happy to assist.
Expert:  Cat Man replied 2 years ago.
Hey. I just wanted to see how things were going. Please let me know if you need more help. I am happy to assist. If my information was helpful. Please leave a good or higher rating so that I receive credit. Thanks.

Related Medium and Heavy Trucks Questions