‘85 300TD Transmission Problem Help
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‘85 300TD Wagon
‘85 300TD Transmission Problem Help
Hey, I have a 1985 300TD wagon with an automatic transmission and it’s nothing wanting to upshift out of first gear.
When I bought the car the bushings were so rotted the gear selector was very loose and so I thought maybe it just was just skipping over drive and selecting “S”, but after replacing bushings inside the selector and on the rod going to the transmission it still feels like it’s not wanting to pull out of first gear.
This is my first old Mercedes and so I’m not familiar with them. Does anyone on here think they may know what it might be, or does anyone know a good shop near Atlanta I could possibly take it to.
Thanks!
When I bought the car the bushings were so rotted the gear selector was very loose and so I thought maybe it just was just skipping over drive and selecting “S”, but after replacing bushings inside the selector and on the rod going to the transmission it still feels like it’s not wanting to pull out of first gear.
This is my first old Mercedes and so I’m not familiar with them. Does anyone on here think they may know what it might be, or does anyone know a good shop near Atlanta I could possibly take it to.
Thanks!
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Joined: Feb 2013
Posts: 207
Likes: 37
From: Beaverdam, VA
W123 300CD, R107 560SL, W211 E320
Your transmission uses a combination of cable and vacuum transmission control. Inspect the cable mechanism on top of your valve (cam) cover for attachment and adjustment. A good starting point is cable adjustment to take the slack out. Then inspect the vacuum line and fittings that run from the modulator on top of your injection pump to the transmission. If the soft rubber fittings at each end are rotted from oil soaking or the vac lines are not a tight fit into them, replace the fittings.
Does your engine stop instantly when you cut the key off? If not, that indicates a vacuum leak somewhere. As with any diesel, vacuum is produced by a vac pump rather than the intake manifold as a gasser. If it is your intent to maintain your car yourself for the most part, a MityVac test tool is an inexpensive good investment.
Please report back your results. It helps everyone.
Does your engine stop instantly when you cut the key off? If not, that indicates a vacuum leak somewhere. As with any diesel, vacuum is produced by a vac pump rather than the intake manifold as a gasser. If it is your intent to maintain your car yourself for the most part, a MityVac test tool is an inexpensive good investment.
Please report back your results. It helps everyone.
