Thanks B.C. and Volvodad, I think this might be it. The car gets sluggish under load and gets hot... The pinging is also noticeable...
The missaligned intermediate shaft could be it. I really did not think about this, I just tryed to play with the camshaft +/- 1 tooth ofcourse w/no succes (the car only runs fine in this setup)...
Yesss, this just might be it!
I remember now I had some difficulty to align the intermediate drive shaft (no marks found). No, I don't have strobe light... Any suggestions on how to align the thing properly?

And thanks again to you all, I'm almost sure this will correct my problem.

Ivch
'79 244Gl
'82 244Ti

Given all the parts you've replaced to correct this problem, I think BC is on the right track. Ignition timing should be something like 12 degrees advanced at slow idle with vacuum disconnected. Did you have to make a large dizzy adjustment after the t-belt work? (A one-tooth misalignment is 19 crankshaft degrees, regardless of the sprocket at which it occurs). What is the actual timing now? (Presume you have a strobe light).
--
Bob (son's 81-244GL B21F, dtr's 83-244DL B23F, 'my' 94-944 B230FD; plus grocery-getter Dodge minivan, hobbycar 77 MGB, and a few old motorcycles)

This a SWAG (Scientific wild-ass Guess)


If the static ignition timing is retarded a little, like one tooth on the timing belt on the intermediate drive shaft, that might account for your overheating.

Another symptom would be a little sluggishness in normal accelerating under load.

Other than that, look for the things other posts mention.

Good Luck,

Bopb

:>)

Could your waterpump have died during installation of the new belt? No circulation of coolant means no cooling. Seems to be the only part not mentioned in this conversation...

good luck!

Leon

Perhaps your gauge is faulty.

Not common in the earlier 240s (ones made prior to '81) but it's still a possibility.

Are you certain that the car is overheating?

I might double check the thermostat, and make sure you got it installed properly. There is a little air valve that is suppose to face up if I remember correctly.

Hope this helps.
--
If you listen to the radio in Portland, OR, you may know me as 'Portland's Favorite Soul Brother!'