Hello, I have a 1979 300sd 116. Can anyone help me with a couple of questions?

1. I am going to install a block heater. How difficult is it and where is the port to install it?

2. Where is the fuel cut off solenoid located?

3. The tach is not functioning. I have replaced the tach amp with no success. Could it be the pickup on the flywheel?

4. what is the best way to flush the cooling system? This may sound funny but ...where is the radiator cap?

Thanks for your help!

Clark

8) I don't have any info on the heater but do have the same question.

Hi Clark and Al Ramsey

Glad to see some other W116 owners on BenzForum. As you can see from my signature I have a W116 turbodiesel. I can try to answer a couple of your questions.

First, the block heater is located on the right/passenger side of the engine. It is hard to see and you may have to remove the starter to get access to the port.

Problems with the tach are very common on this old of a car. Clark you have already addressed the most likely problem by replacing the tach amp. Make sure that the replacement amp is good. Like I say normally replacing the amp is the trick.

The radiator does not have a cap. You add fluid through the bottle.

Again welcome and keep us posted on your classic W116s.

Clark:

One of the common problems with the tach amp is the pins making contact with the diagnostic port. Many have used a "cigarette butt trick" to apply more pressure against the printed circuit board, but I discourage this method. You may want to try taking some fine twisted strand wire and cutting a short length. Un-twist the strands and insert a single strand in each of the port sockets. The wire will bridge the gap between the pin and the diagnostic port socket contact. You may want to try this with both the old and new amp, as you old amp may be perfectly fine.

Regarding DIY on block heaters, I understand they can be a real bear. Be careful to not unseat the bushing the heater is screwed into.

Sincerely,
Scott