help!!! 1981 300 TD Los Angeles
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300td
help!!! 1981 300 TD Los Angeles
So my 300td is leaking oil like a mother... a mechanic looked at it and told me my rear main seal has gone bad and that it wouldn't be worth my money to fix... also my car downshifts really hard. so its looking like i may need tranny work also. does anyone have any mechanic suggestions for these repairs. found a guy in sylmar (mb restoration guy) who said it would cost around 3k to fix. let me know what you guys think or if its even worth my money. thanks...
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83, 300D Federal
I just went throught the hard downshift issue and it turned out to be a Vacuum Leak. In my case the Vacuum Hose to the Transmission Modulator was dosconnected.
The Modulator itself has a Rubber Cap that can Crack and the Modulator Daphragm can also leak when it gets older.
Before you entirely condem the rear Main Seal be sure you Crankcase Breathing System is cleaned out. Trapped Crankcase pressure can make leaks increase.
Other Oil leak areas are the Turbo Oil Supply Tube the come up from the Bottom of the OIl Filter (they have been know to crack or a hole get rubbed thru them) and goes behind the Valve Cover to the Turbo.
The Turbo Drain Tube down where it attaches to the Pan can leak badly when the Grommet and O-ring there is shot.
Part of Oil Leaks from the Valve Cover also tend to head to the Rear.
When you have an Oil Leak issue it is best to degrease the whole Engine and Bell Housing to determine where the Leak is coming from.
From what I have read the Engine needs to be pulled out to change the Rear Main Seal. The Rear Main Seal is a Rope type Seal.
I do not know why it would be loose but did anyone ceck the upper Oil Pan Bolts to see if they are tight. The Lower 1/2 of the Rear Main Seal is in the Oil Pan (not like american Cars where the Rope Seal is in the Rear Main Bearing Cap). So if the Pan Bolts were loose the Rear Man Seal would also be loose.
The Modulator itself has a Rubber Cap that can Crack and the Modulator Daphragm can also leak when it gets older.
Before you entirely condem the rear Main Seal be sure you Crankcase Breathing System is cleaned out. Trapped Crankcase pressure can make leaks increase.
Other Oil leak areas are the Turbo Oil Supply Tube the come up from the Bottom of the OIl Filter (they have been know to crack or a hole get rubbed thru them) and goes behind the Valve Cover to the Turbo.
The Turbo Drain Tube down where it attaches to the Pan can leak badly when the Grommet and O-ring there is shot.
Part of Oil Leaks from the Valve Cover also tend to head to the Rear.
When you have an Oil Leak issue it is best to degrease the whole Engine and Bell Housing to determine where the Leak is coming from.
From what I have read the Engine needs to be pulled out to change the Rear Main Seal. The Rear Main Seal is a Rope type Seal.
I do not know why it would be loose but did anyone ceck the upper Oil Pan Bolts to see if they are tight. The Lower 1/2 of the Rear Main Seal is in the Oil Pan (not like american Cars where the Rope Seal is in the Rear Main Bearing Cap). So if the Pan Bolts were loose the Rear Man Seal would also be loose.
Last edited by Outre; May 25, 2011 at 11:24 PM.
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300td
thanks for the info... did you do all this work yourself? now i know what to look out for... some random mechanic told me it was my rear main seal... i'm keeping my fingers crossed that it isn't...
I just went throught the hard downshift issue and it turned out to be a Vacuum Leak. In my case the Vacuum Hose to the Transmission Modulator was dosconnected.
The Modulator itself has a Rubber Cap that can Crack and the Modulator Daphragm can also leak when it gets older.
Before you entirely condem the rear Main Seal be sure you Crankcase Breathing System is cleaned out. Trapped Crankcase pressure can make leaks increase.
Other Oil leak areas are the Turbo Oil Supply Tube the come up from the Bottom of the OIl Filter (they have been know to crack or a hole get rubbed thru them) and goes behind the Valve Cover to the Turbo.
The Turbo Drain Tube down where it attaches to the Pan can leak badly when the Grommet and O-ring there is shot.
Part of Oil Leaks from the Valve Cover also tend to head to the Rear.
When you have an Oil Leak issue it is best to degrease the whole Engine and Bell Housing to determine where the Leak is coming from.
From what I have read the Engine needs to be pulled out to change the Rear Main Seal. The Rear Main Seal is a Rope type Seal.
I do not know why it would be loose but did anyone ceck the upper Oil Pan Bolts to see if they are tight. The Lower 1/2 of the Rear Main Seal is in the Oil Pan (not like american Cars where the Rope Seal is in the Rear Main Bearing Cap). So if the Pan Bolts were loose the Rear Man Seal would also be loose.
The Modulator itself has a Rubber Cap that can Crack and the Modulator Daphragm can also leak when it gets older.
Before you entirely condem the rear Main Seal be sure you Crankcase Breathing System is cleaned out. Trapped Crankcase pressure can make leaks increase.
Other Oil leak areas are the Turbo Oil Supply Tube the come up from the Bottom of the OIl Filter (they have been know to crack or a hole get rubbed thru them) and goes behind the Valve Cover to the Turbo.
The Turbo Drain Tube down where it attaches to the Pan can leak badly when the Grommet and O-ring there is shot.
Part of Oil Leaks from the Valve Cover also tend to head to the Rear.
When you have an Oil Leak issue it is best to degrease the whole Engine and Bell Housing to determine where the Leak is coming from.
From what I have read the Engine needs to be pulled out to change the Rear Main Seal. The Rear Main Seal is a Rope type Seal.
I do not know why it would be loose but did anyone ceck the upper Oil Pan Bolts to see if they are tight. The Lower 1/2 of the Rear Main Seal is in the Oil Pan (not like american Cars where the Rope Seal is in the Rear Main Bearing Cap). So if the Pan Bolts were loose the Rear Man Seal would also be loose.
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83, 300D Federal
I have never removed the Engine and replaced the Rear main Seal or even the Front Crankshaft Seal. I have read about others and what they had to do on other Forums.
I have changed the Turbo Drain Seal, the front Gasket of the Fuel Injection pump and removed my Oil Filter Housing and changed the Block to Oil Filter Gasket. All due to seeping Oil Leaks.
The worst Oil leak I had on my Car was the Valve Cover Gasket. The leak drained down behind the Engine and down the Bell Housing. If the Engine is not clean someone might think this is a Rear Main Seal leak. Also I did not see that was where it was leaking until I had used up 3 cans of Engine Degreaser.
My Engine was covered with layers and layers of dirty Oil all the way back to the end of the Transmission.
So far I have been able to fix everything on my Car that needed fixing but I cannot say it has always been easy.
I have changed the Turbo Drain Seal, the front Gasket of the Fuel Injection pump and removed my Oil Filter Housing and changed the Block to Oil Filter Gasket. All due to seeping Oil Leaks.
The worst Oil leak I had on my Car was the Valve Cover Gasket. The leak drained down behind the Engine and down the Bell Housing. If the Engine is not clean someone might think this is a Rear Main Seal leak. Also I did not see that was where it was leaking until I had used up 3 cans of Engine Degreaser.
My Engine was covered with layers and layers of dirty Oil all the way back to the end of the Transmission.
So far I have been able to fix everything on my Car that needed fixing but I cannot say it has always been easy.
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Joined: Aug 2010
Posts: 92
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83, 300D Federal
