engine vibration issues
#1
12-05-2015, 02:16 PM
engine vibration issues
OK, so before I started this nightmare of an axle swap, I had a couple of cratered engine mounts which needed replacing.
I did so, with new mounts from a dodge dealer in red deer. I used all new hardware which was equal or above the grade used by dodge. Lifted the engine and torqued the mounts on correctly. 125ftlb to the block. Then set the engine into the mounting horns and torque those to 75lbft. As per Cummins specs.
I didn't get the violent shake at speed, but I still have a vibration at idle. It's not a high frequency, fast vibration, like a guy gets from a low idle setting. It's a low frequency vibration, much like you'd feel in a single mass flywheel equipped 7.3 powerstroke.
Like the engine is wobbling in the mounts.
Transmission mount is a year old. I replaced it when I did the manual swap.
Injectors are new, balanced and lapped at a reputable shop. Now, I installed them, so I spose I could have touched a tip to something I should not have. I am a bit if a rookie with that. Did use a clean pair of gloves for each injector though.
I'm waiting on a new OFV from Tork Tek. Kinda wonder if I'm getting proper fuel pressure, as I also have a slightly long crank time, and a slight dead spot in the Rev band under load in the higher gears. Song have the tooling to test the pressures, but it's a Bosch OFV on a Mopar reman fuel pump, on a truck with 320,000 miles. It's likely cratered.
Beyond the thought of low fuel pressure causing an engine miss, what else could I be looking at with this vibration ? It's not driveline related. Tested that already.
I sit in a friends truck and it runs much nicer. So somethings up somewhere.
I did so, with new mounts from a dodge dealer in red deer. I used all new hardware which was equal or above the grade used by dodge. Lifted the engine and torqued the mounts on correctly. 125ftlb to the block. Then set the engine into the mounting horns and torque those to 75lbft. As per Cummins specs.
I didn't get the violent shake at speed, but I still have a vibration at idle. It's not a high frequency, fast vibration, like a guy gets from a low idle setting. It's a low frequency vibration, much like you'd feel in a single mass flywheel equipped 7.3 powerstroke.
Like the engine is wobbling in the mounts.
Transmission mount is a year old. I replaced it when I did the manual swap.
Injectors are new, balanced and lapped at a reputable shop. Now, I installed them, so I spose I could have touched a tip to something I should not have. I am a bit if a rookie with that. Did use a clean pair of gloves for each injector though.
I'm waiting on a new OFV from Tork Tek. Kinda wonder if I'm getting proper fuel pressure, as I also have a slightly long crank time, and a slight dead spot in the Rev band under load in the higher gears. Song have the tooling to test the pressures, but it's a Bosch OFV on a Mopar reman fuel pump, on a truck with 320,000 miles. It's likely cratered.
Beyond the thought of low fuel pressure causing an engine miss, what else could I be looking at with this vibration ? It's not driveline related. Tested that already.
I sit in a friends truck and it runs much nicer. So somethings up somewhere.
Last edited by Slim Whitey; 12-05-2015 at 02:20 PM.
#3
12-06-2015, 12:01 AM
Bone stock. I believe 13*. When I last had the pump off I bench timed the pump and bolted it back on.
I am very leery about advancing the timing because of the frigid weather here and the unfortunate reality that there are times when the truck sits 5 hours not plugged in at -30C, and then I have to start it.
I am very leery about advancing the timing because of the frigid weather here and the unfortunate reality that there are times when the truck sits 5 hours not plugged in at -30C, and then I have to start it.
#4
12-06-2015, 06:54 AM
*****! I would be too. I have no trouble starting mine in the cold, but cold here is seldom below zero and it's always plugged in at home. And if it isn't home, it's pretty much always running, so...
Anyway, I'm having a difficult time imagining this vibration. I know that when I went from OEM rubber mounts in my Mustang to Prothane poly mounts, the NVH from the engine went up considerably. I didn't mind, but that was a 5.0 gas engine and the 12V is not the same fruit at all. It wouldn't surprise me if your fresh new mounts are transmitting more from the violent Cummins than the twenty year old originals, but I'm probably thinking up the wrong tree here.
Anyway, I'm having a difficult time imagining this vibration. I know that when I went from OEM rubber mounts in my Mustang to Prothane poly mounts, the NVH from the engine went up considerably. I didn't mind, but that was a 5.0 gas engine and the 12V is not the same fruit at all. It wouldn't surprise me if your fresh new mounts are transmitting more from the violent Cummins than the twenty year old originals, but I'm probably thinking up the wrong tree here.
#5
12-06-2015, 10:27 AM
Yeah theres damn good reason I want to rip a webasto off a totalled off cube truck.
And yeah its difficult to explain if you haven't sat in an OBS powerstroke with a single mass flywheel conversion haha.
Uhhh... k...
It's a rhythmic shake of the engine. Not so much a vibration. A vibration is very high frequency. Hundreds of oscillations per minute.
This feel like about 120 oscillations per minute. It shakes the cab slightly. As if the engine is rocking back and forth in the mounts.
I have run the engine and checked the mounts. They allow the engine to torque up on throttle but don't allow movement at steady rpm. Like they should. So they are working.
The more I feel it the more I think it's a miss due to fueling. . .
And yeah its difficult to explain if you haven't sat in an OBS powerstroke with a single mass flywheel conversion haha.
Uhhh... k...
It's a rhythmic shake of the engine. Not so much a vibration. A vibration is very high frequency. Hundreds of oscillations per minute.
This feel like about 120 oscillations per minute. It shakes the cab slightly. As if the engine is rocking back and forth in the mounts.
I have run the engine and checked the mounts. They allow the engine to torque up on throttle but don't allow movement at steady rpm. Like they should. So they are working.
The more I feel it the more I think it's a miss due to fueling. . .
Last edited by Slim Whitey; 12-06-2015 at 10:49 AM.
#7
12-07-2015, 05:30 PM
I did a SM flywheel on my 7.3 cause I the dual mass was scrap metal. Thing had a "whump" to it as soon as I did it.
#8
12-07-2015, 10:28 PM
[QUOTE=Slim Whitey;1103856]OK, so before I started this nightmare of an axle swap, I had a couple of cratered engine mounts which needed replacing.
I did so, with new mounts from a dodge dealer in red deer. I used all new hardware which was equal or above the grade used by dodge. Lifted the engine and torqued the mounts on correctly. 125ftlb to the block. Then set the engine into the mounting horns and torque those to 75lbft. As per Cummins specs.
I didn't get the violent shake at speed, but I still have a vibration at idle. It's not a high frequency, fast vibration, like a guy gets from a low idle setting. It's a low frequency vibration, much like you'd feel in a single mass flywheel equipped 7.3 powerstroke.
Like the engine is wobbling in the mounts.
Transmission mount is a year old. I replaced it when I did the manual swap.
Injectors are new, balanced and lapped at a reputable shop. Now, I installed them, so I spose I could have touched a tip to something I should not have. I am a bit if a rookie with that. Did use a clean pair of gloves for each injector though.
I'm waiting on a new OFV from Tork Tek. Kinda wonder if I'm getting proper fuel pressure, as I also have a slightly long crank time, and a slight dead spot in the Rev band under load in the higher gears. Song have the tooling to test the pressures, but it's a Bosch OFV on a Mopar reman fuel pump, on a truck with 320,000 miles. It's likely cratered.
Beyond the thought of low fuel pressure causing an engine miss, what else could I be looking at with this vibration ? It's not driveline related. Tested that already.
I sit in a friends truck and it runs much nicer. So somethings up somewhere.[/QU
I did so, with new mounts from a dodge dealer in red deer. I used all new hardware which was equal or above the grade used by dodge. Lifted the engine and torqued the mounts on correctly. 125ftlb to the block. Then set the engine into the mounting horns and torque those to 75lbft. As per Cummins specs.
I didn't get the violent shake at speed, but I still have a vibration at idle. It's not a high frequency, fast vibration, like a guy gets from a low idle setting. It's a low frequency vibration, much like you'd feel in a single mass flywheel equipped 7.3 powerstroke.
Like the engine is wobbling in the mounts.
Transmission mount is a year old. I replaced it when I did the manual swap.
Injectors are new, balanced and lapped at a reputable shop. Now, I installed them, so I spose I could have touched a tip to something I should not have. I am a bit if a rookie with that. Did use a clean pair of gloves for each injector though.
I'm waiting on a new OFV from Tork Tek. Kinda wonder if I'm getting proper fuel pressure, as I also have a slightly long crank time, and a slight dead spot in the Rev band under load in the higher gears. Song have the tooling to test the pressures, but it's a Bosch OFV on a Mopar reman fuel pump, on a truck with 320,000 miles. It's likely cratered.
Beyond the thought of low fuel pressure causing an engine miss, what else could I be looking at with this vibration ? It's not driveline related. Tested that already.
I sit in a friends truck and it runs much nicer. So somethings up somewhere.[/QU
Last edited by norske; 12-07-2015 at 10:43 PM.
#9
12-07-2015, 11:54 PM
[QUOTE=norske;1104019]
I just spent twenty minutes responding to this issue and my stupid smart phone erased most of it. DAMMITALL!
Short story.
Try to read between the lines.
One of my trucks:
1995 12 valve dodge extra cab 4x4
Wh1c tcharger
Manual trans
Tork tek adjustable ofv
#100 fuel plate full forward
AFC housing full forward
Light tension AFC spring from "TST"
New lift pump
Your issue sure sounds fuel supply related.
My trucks stumbling issue gradually developed during several trips of towing horse trailer. Rhythmic, slow stumble at neutral idle and medium intensity, shaking stumble if engine was bogged.
These are great trucks. Keep it simple.
• Installed tork tek ofv. Did not help problem (Nice valve though)
• Installed light tension AFC spring from "TST"
• Screwed pre-boost screw in to touch AFC diaphragm shaft then screwed in 180° more.
• Replaced fuel filter.
• Replaced lift pump (this pump must provide enough initial and continuous pressure for the injection pump to function properly)
• Checked and carefully tightened fuel line connections (rubber to metal fuel lines) to stop any air bubbles introduced into diesel.
Pumped the lift pump primer until i heard a hard buzzing just before my thumb fell off, had a beer and a chew in 35° weather and started the engine with one try. Took a cruise when the engine was warm and found that the truck performed better than ever. Very smooth and strong power with 500 greater usable rpm. Very smooth running. No rhythmic loping. No loping under low rpm load. Rips straight up a steep grade without hotrodding the °go fast° pedal.
Cheers
OK, so before I started this nightmare of an axle swap, I had a couple of cratered engine mounts which needed replacing.
I did so, with new mounts from a dodge dealer in red deer. I used all new hardware which was equal or above the grade used by dodge. Lifted the engine and torqued the mounts on correctly. 125ftlb to the block. Then set the engine into the mounting horns and torque those to 75lbft. As per Cummins specs.
I didn't get the violent shake at speed, but I still have a vibration at idle. It's not a high frequency, fast vibration, like a guy gets from a low idle setting. It's a low frequency vibration, much like you'd feel in a single mass flywheel equipped 7.3 powerstroke.
Like the engine is wobbling in the mounts.
Transmission mount is a year old. I replaced it when I did the manual swap.
Injectors are new, balanced and lapped at a reputable shop. Now, I installed them, so I spose I could have touched a tip to something I should not have. I am a bit if a rookie with that. Did use a clean pair of gloves for each injector though.
I'm waiting on a new OFV from Tork Tek. Kinda wonder if I'm getting proper fuel pressure, as I also have a slightly long crank time, and a slight dead spot in the Rev band under load in the higher gears. Song have the tooling to test the pressures, but it's a Bosch OFV on a Mopar reman fuel pump, on a truck with 320,000 miles. It's likely cratered.
Beyond the thought of low fuel pressure causing an engine miss, what else could I be looking at with this vibration ? It's not driveline related. Tested that already.
I sit in a friends truck and it runs much nicer. So somethings up somewhere.[/QU
I did so, with new mounts from a dodge dealer in red deer. I used all new hardware which was equal or above the grade used by dodge. Lifted the engine and torqued the mounts on correctly. 125ftlb to the block. Then set the engine into the mounting horns and torque those to 75lbft. As per Cummins specs.
I didn't get the violent shake at speed, but I still have a vibration at idle. It's not a high frequency, fast vibration, like a guy gets from a low idle setting. It's a low frequency vibration, much like you'd feel in a single mass flywheel equipped 7.3 powerstroke.
Like the engine is wobbling in the mounts.
Transmission mount is a year old. I replaced it when I did the manual swap.
Injectors are new, balanced and lapped at a reputable shop. Now, I installed them, so I spose I could have touched a tip to something I should not have. I am a bit if a rookie with that. Did use a clean pair of gloves for each injector though.
I'm waiting on a new OFV from Tork Tek. Kinda wonder if I'm getting proper fuel pressure, as I also have a slightly long crank time, and a slight dead spot in the Rev band under load in the higher gears. Song have the tooling to test the pressures, but it's a Bosch OFV on a Mopar reman fuel pump, on a truck with 320,000 miles. It's likely cratered.
Beyond the thought of low fuel pressure causing an engine miss, what else could I be looking at with this vibration ? It's not driveline related. Tested that already.
I sit in a friends truck and it runs much nicer. So somethings up somewhere.[/QU
Short story.
Try to read between the lines.
One of my trucks:
1995 12 valve dodge extra cab 4x4
Wh1c tcharger
Manual trans
Tork tek adjustable ofv
#100 fuel plate full forward
AFC housing full forward
Light tension AFC spring from "TST"
New lift pump
Your issue sure sounds fuel supply related.
My trucks stumbling issue gradually developed during several trips of towing horse trailer. Rhythmic, slow stumble at neutral idle and medium intensity, shaking stumble if engine was bogged.
These are great trucks. Keep it simple.
• Installed tork tek ofv. Did not help problem (Nice valve though)
• Installed light tension AFC spring from "TST"
• Screwed pre-boost screw in to touch AFC diaphragm shaft then screwed in 180° more.
• Replaced fuel filter.
• Replaced lift pump (this pump must provide enough initial and continuous pressure for the injection pump to function properly)
• Checked and carefully tightened fuel line connections (rubber to metal fuel lines) to stop any air bubbles introduced into diesel.
Pumped the lift pump primer until i heard a hard buzzing just before my thumb fell off, had a beer and a chew in 35° weather and started the engine with one try. Took a cruise when the engine was warm and found that the truck performed better than ever. Very smooth and strong power with 500 greater usable rpm. Very smooth running. No rhythmic loping. No loping under low rpm load. Rips straight up a steep grade without hotrodding the °go fast° pedal.
Cheers
#10
12-08-2015, 02:04 PM
