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Topic: Cummins Vibration Damper (Read 4069 times) previous topic - next topic

Re: Cummins Vibration Damper

Reply #25 –
If the ECU picks up a timing mark off the outside part, migration can cause incorrect injection timing. Back in the days of stock car racing. we would thread a special tool down the spark plug hole, rotate the engine until the piston hit it and then go backwards until the piston hit again carefully marking both spots. We would then measure half way between the marks and then get true TDC (top dead center). The Chevy harmonic balancer was constructed exactly the same way as the Cummins and the outside was known to shift a small amount or even could be pressed on a tiny bit off. I like picking up the timing marks off the flywheel/torque plate end.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Cummins Vibration Damper

Reply #26 –
What's an ECU.....??!!?!! ;D

Mechanical cummins....it'll run during and after nuclear apocalypse--good to keep ahead of the zombies.
1998 U270 34'

Re: Cummins Vibration Damper

Reply #27 –
Quote from: krush –
What's an ECU.....??!!?!! ;D

Mechanical cummins....it'll run during and after nuclear apocalypse--good to keep ahead of the zombies.

Yea baby, tie wire up the shutoff solenoid, wrap a rope around the pulley, lead it out the side and pull it with the toad....she'll bust off!  Don't need no stinkin ecu, get better fuel mileage without it too.  Been far too much praise for those screamin jimmies around here lately... ;D ;D ;D
"Not so  long ago we were a nation of risk takers, riding five million pounds of  thrust straight into space."  Joe Gresh
Chuck Pearson
1996 U295
2018 Can Am X3 TurboRS

Re: Cummins Vibration Damper

Reply #28 –
I feel the same way about my 1987 Mercedes 300D.  As long as I park it on top of a hill and keep the tank filled with diesel, I can start it and run it just fine without any electrical parts whatsoever.  I will need to open the hood and use the manual shutoff when done, we don't need no stinkin' key.
Tom Lang K6PG (originally  KC6UEC)
and Diane Lang
2003 38 U295 build 6209
2016 Jeep Grand Cherokee Summit Ecodiesel
still have tow-ready 2006 Acura MDX 
Temple City, California
Motorcade 16681 California Chapter President
SKP 16663 member of SKP Park of the Sierra, Coarsegold California
FMCA F071251
Retired electrical and electronic engineer

Re: Cummins Vibration Damper

Reply #29 –
Quote from: Tom Lang –
I feel the same way about my 1987 Mercedes 300D.  As long as I park it on top of a hill and keep the tank filled with diesel, I can start it and run it just fine without any electrical parts whatsoever.  I will need to open the hood and use the manual shutoff when done, we don't need no stinkin' key.

Ahhh....you got me beat there.  As Booger said when meeting Snotty in Revenge of the Nerds 2, "Master!"
"Not so  long ago we were a nation of risk takers, riding five million pounds of  thrust straight into space."  Joe Gresh
Chuck Pearson
1996 U295
2018 Can Am X3 TurboRS

Re: Cummins Vibration Damper

Reply #30 –
Quote from: Kent Speers –
Some of the FoFum members may remember that Jeff and Carol S had a 93, U225 (Rear Radiator) several years ago where the Harmonic Balancer came apart while traveling in West Texas. The outer ring got up into the cooling fan and destroyed it. Somehow it did not hit the CAC or the radiator but fan parts were found all over the engine compartment and even back on the hood of their Jeep towed. The outer ring landed and was found on the rear coach frame.

This was the first time I had ever heard of one coming apart. The Belts had just been changed by both FOT and worked on at a Freightliner dealer so there was apparently no sign of the pending failure. Keep in mind that being a rear radiator unit visual inspection would be pretty tough.

Just keep in mind that harmonic balancer failure can be pretty serious. They had a $1200 tow, bill covered by Good Sam, and we all spent about a week in Fort Stockton, TX awaiting parts and repairs.

We just had the same thing happen. On our way to Lake Livingston, TX we noticed our engine temp had climbed to approximately 215 and was still rising. We pulled over into the Loves north of Lufkin and upon checking found our cooling fan had been severely damaged. Keith R from MOT came down and nursed the coach to Nac while we followed in the toad.

Upon inspection, he found that the vibration damper had failed. We never found the missing part nor most of the fan. Two blades were found (one in the shroud and one resting comfortably up on top the engine) and three small to medium size shards (two in the shroud and one resting on the platform under the bed). Miraculously, there is no apparent damage nor did the belt come off of the crankshaft. 

We have the Cummins 6B5.9 230HP engine with 135,000 mi. We would encourage anyone with similar engines to check this. The Cummins replacement part number is: 3918999

Deb, Jeff, and dog Honey (also in memory of previous traveling partner, Ralph)
The Jupiter 2: '92 36' U225 SBI, Build #4086
230 Cummins to 300hp with Banks Turbo
Monocoque Chassis and Pac Brake
The Space Pod: '16 Kia Soul Flat Tow

Re: Cummins Vibration Damper

Reply #31 –
Jeff, at least it didn't go through the radiator.
Chris
1999 U 320 DGFE
Build Number 5523
Chris & Elka Lang
In the field, Lonoke AR

Re: Cummins Vibration Damper

Reply #32 –
Quote from: Chris m lang –
Jeff, at least it didn't go through the radiator.
Chris
We are so thankful for that. Shudder to think what might have happened.
Deb, Jeff, and dog Honey (also in memory of previous traveling partner, Ralph)
The Jupiter 2: '92 36' U225 SBI, Build #4086
230 Cummins to 300hp with Banks Turbo
Monocoque Chassis and Pac Brake
The Space Pod: '16 Kia Soul Flat Tow

Re: Cummins Vibration Damper

Reply #33 –
Detroits with the rear radiator may also experience an OEM fan failure that can also destroy the radiator. Make sure you have the upgraded fan installed.

Pierce

Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Cummins Vibration Damper

Reply #34 –
I believe Pierce is talking about the fiberglass fan that can fatigue and come apart that should be replaced.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Cummins Vibration Damper

Reply #35 –
FWIW, that vibration damper is held together by the bonded rubber ring.  It really is an age limited part.  Something to replace on schedule and not need.
1992 Foretravel Grand Villa
U225 SBID Build No. 4134
1986 Rockwood Driftwood
1968 S.I.A.T.A. Spring
1962 Studebaker Lark
1986 Honda VF700C
1983 Honda VF750C
Charlie, the Dog was broken out of jail 24 Oct 2023
N1RPN
AA1OH (H)e who must be obeyed.
 

Re: Cummins Vibration Damper

Reply #36 –
Replaced mine a couple of months ago on my 8.3,very easy no puller needed,old one out of specs.
96 U270 BUILD 4810
85 380SL
Drummonds TN.