No compression in Cylinders 4, 5 and 6 Help

Thank you. Your analysis is informative. The tech even said in his statement that it might be the.starter. I will have bring up the valve adjustment to my mechanic when I get to Chicago

 

Most likely the OP isn't going to see this but here goes anyway

Did you have problems with the batteries in the EPU?

If not, why the hell did they even touch the EPU batteries? Did they actually test them and show you they were bad or just say they were?

I had a FL dealer replace 4 new batteries on a driver without even testing them, I told the shop manager to put them in the side box of the truck and I'll pay the core after dealing with a driver who refused to pay, NOT ONE OF THE BATTERIES WAS BAD when it arrived here, they were holding a great charge and I put two in my beater truck and they are still being used after three years.

They ran a relative compression test which is a "let's see if we have to run a mechanical compression test". IF they are a Detroit Diesel shop (meaning they represent DD) then the moron mechanic ignored DD explicit instructions to confirm each "below 85%" result from the relative test by doing a mechanical test on each cylinder.

This tells me that your valves may be too tight, did you do the overhead or did a shop do it? I was told (maybe they are wrong) but the back bank of 3 needs to be a little loose, especially 6.

That's good, hope nothing happens on the way back to chicago.

If it is YOUR truck, why are they doing anything to it?

Bring it to a Detroit Diesel shop with a good reputation.

Maybe, I would just Go Go Go (safely of course).

Dealers employ part changers, not mechanics. Mechanics troubleshoot problems, they know before hooking up the computer what a problem could be.

 

I just started driving soI I won't be able to thoroughly answer your questions and statements:

Question one why go to the company's repair shop when I'm on a ln op
Answer I have been with this company for over two and a half years from a company driver to a honora they have always John's business with me professionally so it's kind of like my small business but I made it America kind of stay in the system that supports you

Question why did I have that epu batteries changed those batteries were originals and they were weak I knew it for quite a while and they should have been changed quite a while back

Question did the truck start this morning easily
Answer yes it did

Question why didn't the dealership do a mechanical compression test
Answer I asked him that and they said that they will need to start taking things apart to do that

Question was that dealership a scam
Answer that was the only dealership that I actually stayed in they had great reviews and they seemed pretty professional

Question could all three cylinders go bad on a compression test
Answer after watching countless YouTube videos yes they can so I do not in the least bit recommend deadheading or driving more than 20 miles and anybody's truck
Then why the hell am I driving?
Cancer I don't have any coolant smell fuel smell white smoke or shaking engine I am taking the rest and I will be monitoring and get all my goal is to get a partial low going to Chicago anything under 20,000 lbs to pay for my fuel cost

Question but why not go to a Detroit diesel mechanics
Answer I can get a loaner truck from the company if I have major repairs to do to the engine it'll be really difficult taking my trailer from wherever I can go get the repairs done I own both the truck and trailer though they're not paid off

I hope this answers all the questions

 

Good luck with the ride home. I understand wanting to get home where you can be comfortable with the mechanic and sit home, Not in a waiting room.

 

Man, you just got a bad tech. I would bet that batteries were weak, Truck cranked slow, ether helped it start for that and only that reason. 2019, runs great. Started fine this morning. Forget everything and run the Truck. There’s nothing wrong with it. Save your money. Don’t waste another dime trying to diagnose something that doesn’t exist. Reminds me of an old saying. If you go to a barber, you’re going to get a haircut. Be glad you didn’t let them start tearing apart your perfectly fine engine. No telling what the end results wound be. Probably a whole rebuild or reman engine, costing more than the Trucks value.

 

Thanks

 

I had a valve adjustment done about a month or two ago so I just want to make sure that they didn't tighten them too much or close the head and correctly whatever so that's the main reason why I definitely want them to do another test when I get to the repair shop and if need be have them open it up

 

It’s your money. I would talk to your Mechanic that did the overhead, if worried about it. No need to try to buy peace of mind. You already paid that bill. Should be good for at least a year and 100k. If it’s running good, getting good mpg’s, I’d leave it alone,

 

The one time I had to use ether. It was because the fuel pump was sucking air. It was only a problem when the tanks were less then half full. It also had erratic idle. As long as the tanks were above half. Nothing was wrong.

Later on that same truck lost 2 cylinders and was adding fuel to the oil. An overhead cured that problem. But I had to limp it home on 4 cylinders. That was not fun with a load.

Ether I'd say you had a fuel problem. If 3 cylinders were indeed down. Even bad batteries would crank it over fast. Since there's no compression. If only 3 cylinders were firing. You won't be packing a load anywhere. The truck would be shaking also.

I don't know what kind of damage a semi motor would suffer packing a load on 3 cylinders. But I can't imagine it be pretty. Definitely won't do the dpf any favors. You could be looking at an expensive motor repair PLUS emissions repair.

When there's popping out the intake or exhaust. It's a valve problem. Your overhead might be too tight.

You said the truck started up. So it was probably high time for new batteries. And there's nothing wrong with the motor. I'd probably have the overhead rechecked. But those reports don't make sense. I don't think that mechanic was accurate in his diagnosis.

 

Thank you. I ended up picking up a 26k pound load from Minden, Nebraska going to Forest Lake, IL
I am in Illinois now and have not lost any power, nor any white smoke or fuel and coolant smell from the exhaust. The truck cranks over easily and this is a Freightliner and cranks over easily even on Opti Idle.
I let my mechanic know all of this and he said just bring the truck over just to be sure.
While traveling through Nebraska I called a Dyno Test repair shop and explained what was going on. They said the Dyno won't be able to diagnose that.
The best test is to take the injectors out and do a mechanical compression test. This place didn't have availability until next week.

I will update when I our repair shop diagnoses the issue. I will ask them to do the mechanical compression test if they think that would be best.