1970 Mercedes 300SEL 6.3 need help
 

Hi ,

We would like to ask your group to help to find out why our 1970 Mercedes 300sel 6.3 is suddenly having problems after a tune-up.
Our nonprofit MatchingDonors.com organization has a donated 1970 Mercedes 300 SEL 6.3 that has run well for 4 years except for two things:
1. a very slow leak in the air suspension. After the car runs for about 20 minutes it is raised up fully, and it takes about 5 days for the air ride to deflate.
2. After driving for about 2 hours, it has always stalled out. We then could put the gas pedal to the floor and restart it, blowing smoky exhaust out the back for about 15 seconds then drive it again for 2 hours.
We have been using it for four years as our showcase car for our Cars4Kidneys program. It looks great and had no need to put a lot of money into it
Last week we brought it to our local mechanic to tune it up to solve the stalling problem.
After the tune up, it drove great, and we drove it back to our location about 1 mile away. Again, after about 5 days the air ride deflated – as expected. So we started the car and ran it – after about 2 hours the car did not raise up and there were other problems that did not exist before.
1. The never car rose up and it seems the compressor does not run.
2. The engine runs very hot now
3. The vacuum door locks now do not work
4. The electric fan in front of the radiator now does not run,
5. The battery is now reading 17 volts on a digital voltmeter.
I just talked to the mechanic and he said he did nothing electrical and he did the following for the tune up
1. Replaced the distributor cap
2. Checked the points and condenser
3. Replaced the distributor rotor
4. Repaired three ignition wires from distributor cap to the spark plugs
5. Retapped the sparkplug on the second or third cylinder on the passenger side
6. Replaced all the sparkplugs
7. Cleaned the throttle body
8. Put duct tape around the air intake boot that was torn
I talked to a great gentleman, Martin Werminghausen, who is an expert on the air suspension of the Mercedes 300 , 600 and 109. He told us to first drain out the air tank then pump up the air suspension with a compressor to see if there were any new serious leaks.
We did and the car went up great and is still up after 24 hours. Which rules out any new leaks.

Can you help us with this question or put it out to your group to see if they have an answer? Thank you for your help. We can supply the title and pictures of the car if needed.

Best,
Paul


Paul Dooley
CEO/Founder
MatchingDonors.com
766 Turnpike Street
Canton, MA 02021
781-821-2204

I'm saying this in all seriousness, please stop driving it as you might of already done serious damage to this car.

I hope the mechanic who is looking after this car knows 6.3s inside and out. If the car is running ''very hot'', stop driving it asap. The air ride problems are the least of your worries if you blow a headgasket or warp the very very very expensive heads.

This car is now an appreciating asset. Don't be afraid to take it to a 6.3 expert and let him do his thing. Its not wasted money to spend money on this car as prices of them are on the rise and aren't slowing down.

Start here: Hatch & Sons Automotive, LLC. Hudson, MA - Mercedes Benz, Porsche, Ferrari, BMW, and other Fine European Motor Car Sales They are up in Hudson. Get them on the phone and explain your situation. If they can't help you, they will know someone who will.