daldelta

Thanks DD and Rich for your help: My exhaust manifold leak is at the #1 or #6 cylinder, the cylinder furthest away from the back of the motorhome. The leak is at the gasket where the exhaust header bolts to the manifold. I over torqued it when I changed the turbo. The way I noticed the leak was seeing some black residue in that area around the gasket. I did a bubble leak test back when I changed the turbo around 2 years ago and the leak did not seem that bad, that was at idle speed and may have gotten worse. It was very disappointed to see after all the work it took to change the turbo, I could not check for leaks until everything was back together. I did buy a very expensive and very high temp sealant and applied the best I could around the leak. I do not believe it really helped. Not sure the exhaust leak is only problem, since I had the same climbing problem before I changed the turbo? The lack of power was the reason I changed the turbo and Cummins told me it was bad. I do not believe there was an exhaust leak when the old turbo was on. I have checked all the hose clamp fittings, I have not checked the hoses themselves for leaks, so I will make sure to do that. How do I check to see if the turbo is free to spin? I assumed it was working since I had boost going down the road. I have not checked the air compressor hose; will the water leak test be adequate to check for the leak? I will do some research to figure out how to check the output pressure of the fuel lift pump. Any good web sites I should check out for how-to info? With the anxiety of the motorhome not moving up the hill I failed to notice what the engine RPM is reading, I am thinking the engine does not even rev up; it just sits there and then slowly starts to roll forward. It is really is like nothing happens when I press the throttle. Sure hope it’s not the torque converter, I have not noticed any kind of slippage. Any checks to verify this? I have changed the filters and fluid in the tranny--Allison 6 speed. It has a fluid level check and it does read OK and seems to shift fine on the road. Should I look into a potential throttle issue? It has the Electronic throttle control. FYI- I did have another issue once where I had no power and found the exhaust brake was sticking closed. It released with a couple of sprays of WD-40 on the plunger shaft. I always check it now before I leave to insure it is not stuck closed. I was on the road from a campground when that happened not at my home on the hill.(As I mentioned, I do make sure the exhaust brake is not stuck shut before I back out of my pole building so I don’t believe it has anything to do with my power issue.) Thanks you again, all help is greatly appreciated. Dave

Hello FMCA: Current Situation-- I have a 98 HR Imperial 40' motorhome with a Cummins mechanical 8.3 @ 325hp. My problem is no power on a hill from a dead stop. I live in Tennessee in the hills, and due to property constraints when I back my motorhome out of my pole building I have to crank the coach hard to the left once my front end clears the building, I am also going downhill as I back out. After I have backed up as far as I can, to get out of my driveway onto the main road my wheels need to be cranked hard the opposite direction and climb uphill from a dead stop. I hold my breath every time because now when I bury the throttle the motorhome does not want to move. The engine is flat and I have no boost. After a few tries it usually very slowly starts to move and I am able to get out of my driveway onto the main road. Once I am on the road I climb hills with no issues and seem to have plenty of power, my only issue with power is in the position stated above. History- The engine has 48K miles and the only engine repair has been replacing the turbo charger. I do my own maintenance (not a professional) and changed the turbo myself after I was told by a Cummins dealership that it needed replaced. I had to be towed from my driveway to Cummins because on that occasion I could not get the motorhome to go up the hill. Cummings changed the waste gate and said it is a temp fix to get me home. I changed the turbo when I got home, still did not help much, but now slowly the motorhome climbs. It’s only a matter of time before I will need to be towed again. What can I do to get the power needed to get up the hill from a dead stop? Waste gate adjustment, fuel pump etc.? I do have a slight exhaust manifold leak, and I have adjusted the valves a couple of times, maybe I did something wrong there. Hard to tell when the problem started since I lived in Indiana (very flat ground) when I adjusted the valves and did not have any dead stop hills to climb with the wheels cranked. When I changed the turbo I added a boost gauge, and have seen as much as 20 pounds going uphill moving down the road. All crossovers and hoses/fittings are OK and do not seem to be the problem. Thank you for your responses and help. Sincerely Dave