1975 Mercedes-Benz SL 450 SLC from North America - Comments

I have a 450 SLC 1975 and it runs HOT HOT HOT. I replaced the engine recently, but it's up in the 220F range and I don't know why. Can somebody help? Live in Cally.

Pretty good car, but I don't get why it runs hot, everything was replaced and it runs beautiful, but it's still hot.

Check the water pump belt -- too loose?

They all run hot.

I have read somewhere that it might have to do with the american front-spoiler, or was it a third party spoiler, that is blocking one third of the airflow to the radiator... this was the case for a few people driving the 79 5.0 edition anyway...

BR

I own a 350sl and a 450sl Mercedes and like them a lot. I have a 1976 350sl and a 1975 450sl. The 1976 350sl which is a gray market car, meaning, it was made for the European market and it is slightly different configuration than the ones sold in the US, furthermore, the 350sl was sold in the US in 1972 only. My car comes equipped with a 3.5 liter engine, four speed manual transmissions, all manual windows and seats, small bumpers, the suspension is a bit lower and tighter, everything else is about the same. The 350sl did not do well in the 70s because Americans wanted more power, then MB introduced the 450sl. The 350sl is beautiful and drives like a dream; I have 180k miles and the engine still running strong. This is one of my favor cars because it is a classic car with some sports car characteristics.

The 450sl is great car as well with automatic transmission, softer suspension, but even with the 4.5 liter, it does not seem to be as responsive as the 350sl.

I get an average of 17 to 18 mpg on the 350sl and about 14 to 15 on the 450sl. I should also mention that I am from CA and we have catalytic converters in our cars and because of our state oil refinery requirements, our gas does not yield as many miles as other states.

All in all, they are beautiful looking cars, great value and will stay looking great and classy forever because they were made well. These cars may not be good commuters anymore, but they are fun and great weekend car. They are mechanically sound, but when something goes wrong and you do not have a friend in the business, it could be very expensive.

Sincerely,

Northern Cal.

It might have something to do with the thermostat. Buy a thermostat that lets in more water at a lower temperature since you live in ca.

They have the catalytic converters under the hood. It cooks the hell out of everything and raises engine compartment temperature considerably. Huge design flaw. It was corrected within the next year or two I believe.