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Big Seafoam OOPS, 79 300TD

2035 Views 13 Replies 4 Participants Last post by  reinventthewheel
Ok, so my last car was a gas VW Jetta and when I got it, it had an incredibly dirty intake manifold. I did a few seafoam treatments through the vacuum lines and it worked miracles.

I just got a '79 300td (non-turbo) and there's been a lot of blow-by. The air filter and housing is full of dark oil, and the car smokes much more than it should.
My thought was that since I was dealing with a similar problem, I would turn to a similar solution. I sucked a half a can of seafoam through the thin vacuum line coming off of the thick one that leads to the brake booster.

Since the big cloud of smoke didn't come out afterwards I just started to look up Seafoam treatments on these vehicles and found all this scary stuff about hydro-lock. Yikes.

I've only driven about 1/2 mile since doing the treatment, but I'm supposed to be driving almost 300 miles tomorrow (hence the desire to clean out the intake before getting on the road).
SO! Did I fuck things up? What do I do to fix it?
Also, how can I clean out the intake manifold? Will seafoam in the fuel do the trick?

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My 2 cents is use Mobil 1 synthetic 0W-40 (MB uses this in almost all of its engine). Use Seafoam or Diesel Purge in the fuel (videos on YouTube) and change fuel filters and change them again any time you feel that "she aint pulling the hill very well" feeling. Use the Seafoam in the crank case for about one hour and change the oil & filter. Unless there is physical damage to the motor you will feel a difference.

Also have the valves adjusted. This can make a huge difference on diesels with mechanical lifters. Mercedes Diesel Valve Adjustment Procedure

A good test to determine if you have had results is the 40-60 mph test. Time 40-60 several times so you have a good average. After doing the diesel purge or seafoam test again. I gained about 1-2 sec on my 300sdl.

You can use diesel purge or seafoam for this...

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