The problem:
1. The truck is a (2500) 1997 model that I purchased new.
2. Present odometer reading 95,000
3. TST #8 plate installed at 47,000 miles
4. Sun Coast converter installed at 48,000 miles
5. All oil and oil filter changes performed per Dodge schedule (mostly Cummins filters and Shell Rotella T oil)
6. Other scheduled maintenance (transmission, differential, valve adjustments and fuel filter replacement) performed per manufacturer’s schedule.
7. Most of its fuel was purchased at high volume stations --- (it has never had a water in fuel incident)
8. Engine has always started easily and runs smoothly (idle to full RPM)
9. Over its lifetime it has towed five different travel trailers (two fifth wheels and three tongue pulls) ranging in weight 6500# to almost 11000#.
10. About eighteen months ago we sold our fifth wheel and decided not to replace it.
11. I continued to use the truck for transportation. Sense we live way out in the boon-docks this truck rarely sees an engine start that isn’t followed by at least 10 plus miles of highway driving.
12. I have a lead foot and normally run the speed limit --- despite that it gets 19 to 21 mpg (those numbers are not spot checks. I have a kept a spreadsheet that recorded every gallon of fuel added to this truck --- this mileage is calculated on a three fill-up average).
13. This truck has been to the Rockies several times and has towed a ten thousand pound trailer above 10,000 feet, without incident.
14. This is not a super tow vehicle but from my point of view it’s everything I need. No matter the altitude, I have always been able to down shift, bring up the RPM and pull any hill on any (paved) highway. As best I can tell this is an average truck and engine given its age and after market modifications.
Now that’s the background, and this is the rest of the story. We decided to get back into the trailer owner ranks but to purchase a used basic (30’ with slide) tongue pull. The new (used) trailer weighs 7500 to 8000 lbs and is a quality unit that tracks very well. On the way home with the new (used) trailer in tow the engine ran fine the transmission shifted as expected but the power was not what it should be. Boost pressure was down, as was exhaust temp and I could not get the engine rpm much above 2300 in any gear. Boost pressure would on occasion bump up to 18 or 19 lbs but only when rpm was below 2000. (at higher rpm the boost wouldn’t get much above 10#). Another problem is that, I've reach the age where I forget more than I remember, so began to wonder if I had just forgotten how the truck performed in the past. Just check thing out I decided to take the trailer out on a 650 mile (round trip) get-away. We spent most of the first 250 miles on I45 and I10 running between 60 & 70 MPH with more than enough power for those speeds. Out in the Texas hill country we took on some steep (but short) grades, if the engine RPM stayed below 2000 it pulled well enough (but not with the power I remembered). If it down-shifted to lower gear the power, boost and exhaust temp would drop off as rpm went up and it acted as though the governor was set at 2400 RPM. I convinced myself the problem was low transfer fuel pump pressure. Just as a shot in the dark I had decided to replace the fuel bypass valve when I got home.
On the way home we must have passed through the twilight zone because engine power started to improve. By the time we got home my truck felt as though it had been through the shop, but still wasn’t quite up to full power. How can this be (???) ---- machinery doesn’t fix itself (???) --- something has to have happened… The only thing that had happened here was that the truck had towed a trailer at highway speed for something over 650 miles. The only thing that occurred to me was that the waste gate was (perhaps) stuck in the partially open position. That was caused by a carbon build-up that ultimately burned away with the increase load on the engine. That’s a whole lot of guesswork but the best my (uninformed) imagination could do.
In an effort to do something (right or wrong) I disconnected the hose that ties the waste gate actuator to the charger output and connected it to an airline. I put pressure (about 35#) on and let it off several dozen times. I took the truck out (solo) and my imagination says “it's running better” --- on one zero to seventy run I was able to bump the boost pressure over 20# and exhaust temp a hair over 1000 deg with peddle to the metal. That's getting really close to the way I remember this truck’s past performance … Keep in mind that I don’t want to race or challenge any off road hills, all I want is a good reliable trailer tow vehicle …
All that leads to these questions:
1. Is this guess about the carbon build-up a real possibility?
2. Is it common for the B 5. 9 to do this?
3. Other than exercising (working the engine by pulling a load) what can be done to prevent it?
Thanks for your response---
Old George (AKA Bewildered)
1. The truck is a (2500) 1997 model that I purchased new.
2. Present odometer reading 95,000
3. TST #8 plate installed at 47,000 miles
4. Sun Coast converter installed at 48,000 miles
5. All oil and oil filter changes performed per Dodge schedule (mostly Cummins filters and Shell Rotella T oil)
6. Other scheduled maintenance (transmission, differential, valve adjustments and fuel filter replacement) performed per manufacturer’s schedule.
7. Most of its fuel was purchased at high volume stations --- (it has never had a water in fuel incident)
8. Engine has always started easily and runs smoothly (idle to full RPM)
9. Over its lifetime it has towed five different travel trailers (two fifth wheels and three tongue pulls) ranging in weight 6500# to almost 11000#.
10. About eighteen months ago we sold our fifth wheel and decided not to replace it.
11. I continued to use the truck for transportation. Sense we live way out in the boon-docks this truck rarely sees an engine start that isn’t followed by at least 10 plus miles of highway driving.
12. I have a lead foot and normally run the speed limit --- despite that it gets 19 to 21 mpg (those numbers are not spot checks. I have a kept a spreadsheet that recorded every gallon of fuel added to this truck --- this mileage is calculated on a three fill-up average).
13. This truck has been to the Rockies several times and has towed a ten thousand pound trailer above 10,000 feet, without incident.
14. This is not a super tow vehicle but from my point of view it’s everything I need. No matter the altitude, I have always been able to down shift, bring up the RPM and pull any hill on any (paved) highway. As best I can tell this is an average truck and engine given its age and after market modifications.
Now that’s the background, and this is the rest of the story. We decided to get back into the trailer owner ranks but to purchase a used basic (30’ with slide) tongue pull. The new (used) trailer weighs 7500 to 8000 lbs and is a quality unit that tracks very well. On the way home with the new (used) trailer in tow the engine ran fine the transmission shifted as expected but the power was not what it should be. Boost pressure was down, as was exhaust temp and I could not get the engine rpm much above 2300 in any gear. Boost pressure would on occasion bump up to 18 or 19 lbs but only when rpm was below 2000. (at higher rpm the boost wouldn’t get much above 10#). Another problem is that, I've reach the age where I forget more than I remember, so began to wonder if I had just forgotten how the truck performed in the past. Just check thing out I decided to take the trailer out on a 650 mile (round trip) get-away. We spent most of the first 250 miles on I45 and I10 running between 60 & 70 MPH with more than enough power for those speeds. Out in the Texas hill country we took on some steep (but short) grades, if the engine RPM stayed below 2000 it pulled well enough (but not with the power I remembered). If it down-shifted to lower gear the power, boost and exhaust temp would drop off as rpm went up and it acted as though the governor was set at 2400 RPM. I convinced myself the problem was low transfer fuel pump pressure. Just as a shot in the dark I had decided to replace the fuel bypass valve when I got home.
On the way home we must have passed through the twilight zone because engine power started to improve. By the time we got home my truck felt as though it had been through the shop, but still wasn’t quite up to full power. How can this be (???) ---- machinery doesn’t fix itself (???) --- something has to have happened… The only thing that had happened here was that the truck had towed a trailer at highway speed for something over 650 miles. The only thing that occurred to me was that the waste gate was (perhaps) stuck in the partially open position. That was caused by a carbon build-up that ultimately burned away with the increase load on the engine. That’s a whole lot of guesswork but the best my (uninformed) imagination could do.
In an effort to do something (right or wrong) I disconnected the hose that ties the waste gate actuator to the charger output and connected it to an airline. I put pressure (about 35#) on and let it off several dozen times. I took the truck out (solo) and my imagination says “it's running better” --- on one zero to seventy run I was able to bump the boost pressure over 20# and exhaust temp a hair over 1000 deg with peddle to the metal. That's getting really close to the way I remember this truck’s past performance … Keep in mind that I don’t want to race or challenge any off road hills, all I want is a good reliable trailer tow vehicle …
All that leads to these questions:
1. Is this guess about the carbon build-up a real possibility?
2. Is it common for the B 5. 9 to do this?
3. Other than exercising (working the engine by pulling a load) what can be done to prevent it?
Thanks for your response---
Old George (AKA Bewildered)