15th May 2008, 18:07

I just inherited a 1986 420 SEL. The car just turned 100K miles. It is in mint condition. The only issue that I have is that the A/C does not seem to cool. I have had the vacuum replaced added freon and done just about everything that I can think of. I need cold A/C in Texas. Anyone have any advice?

19th May 2008, 20:56

I have a 1991 420 SEL and it's been great despite a couple of issues. One that bothers me most is a jingling noise that seems to be coming from front end that I can't figure out. Second is sometimes after starting cold or warm, it tends to choke and stall. Any help, I'd really appreciate it.

PSarapochiello@aol.com

Thanks So Much! Paul.

20th May 2008, 13:36

I have heard the problem is sometimes the monovalve on the 420SEL related to the a/c problem. It is $40.00 for a rebuild kit. An MB dealer wanted to charge me $250.00 for the entire assembly and didn't know about or have the rebuild kit. They are online and can be done in 20 minutes with a screwdriver and wrench. Remove the power wire and then loosen 4 screws, remove and replace.

17th Mar 2009, 22:49

I have a 1990 420SEL with 102,000 miles on it. I am having head gaskets, valve job, transmission reworked, steering pump seals replaced. This will cost 7000 dollars, but the car is worth it! This car is immaculate (white exterior and palamino interior). It is so much better built than anything new on the road. I will keep the car forever and then hand it down to my son. It is sure to become a classic.

9th May 2009, 06:03

My 420SEL continues to perform almost like new. As long as you keep up on the maintenance, the car will run forever. If you take the cost of annual maintenance and divide it up by 12 months... (Assuming the car is paid for) the monthly cost to keep a 420SEL on the road is not much. Try buying a new car! Car payments, insurance etc will go through the roof. The Benz models are ageless and never go out of style. 10 years from now the 420sel will still be one of the best car in the world.

Be prepared to spend $4K per year (Can $) on maintenance, including a good clean / detail in the Spring etc. Rust proofing, switching tyres (snow and reg. tires)

I don't drive mine from Nov to April. I have learned now to move the car once a month, so the brakes don't rust! At great expenses!

Find A GREAT Technician to work on your car, pay him well, and treat him well. don't look for deal at local Specialty Chains etc. They know NOTHING about this type of car.

They will put a 16 year old apprentice to work on your car!

Look for a grey hair tech!!!

21st Aug 2009, 20:18

I just purchased a 1986 420 SEL. It has lots of go and not much whoa!. Besides a few kinks and minor problems, it is a daily driver. Yes there is an oil leak from the rear main and front trans pump. Yes the front fender and front bumper are a bit rusted. Replacement parts are available and it keeps me busy. Good thing I am a mechanic and am able to fix the problems myself. Watch for it in up coming auto shows as the restoration to factory specs takes place over the next two years.

21st Dec 2009, 12:16

Idling is common and can be caused by age. What many people forget to look at is that there is rubber gasket around the air intake manifold, (underneath where it connects to the block.) These things start to dry out and leak. This can cause rough idling that is subtle at first, but gets worse as time goes on. This is usually the case in vehicles of this age, regardless if they have 3,000 miles on the clock or 250,000 miles. These rubber goes with age. To get to them takes some disassembly, and ya average DIYer can do it with little time.

21st Dec 2009, 13:08

Great cars - own 3. If your 420SEL won't start - always check the small fuel pump wire attached to the positive battery post. It must be spotlessly clean or your fuel pumps will not work.

Otherwise replace the track rods on frontend every 80K to keep the front suspension from rattling. Check timing chain as needed and use Mobil 1 oil. Don't need premium gas, have rebuilt several motors that ran on regular and the pistons and heads were fine.

28th Jun 2010, 13:50

I've had a 1986 420 SEL Mercedes since I turned 16. It's got almost 300k miles on it, faded paint and chipping, no hood emblem, and a broken muffler.

It is still the most amazing piece of foreign automotive engineering and stability I have ever seen. This car has been just outstanding to me; I wish I had the money to cosmetically fix it, but other than that it has treated me so well.

The engine seized up for awhile when no one was driving it, but some tender love and maintenance had that engine roaring back to life. It's a V8 with a turbo charger and runs on premium.

I love this car, and if you ever find one, buy it on the spot. They simply will never die, it's just a fact, and if you ever get in a wreck, you might as well be driving a tank.

LOVE THIS CAR SO MUCH!

7th Jul 2010, 21:07

Tell me how you get the turbo charger on there!

7th Jul 2010, 21:09

Running a MBZ on anything but premium when the sticker says to is no good. If you do, don't complain when it breaks, stop running or performing right. Makes me wonder what other corners have been cut when a person can't even come up off a few extra pennies a gallon to put in the proper fuel.

15th Jul 2010, 11:14

1987 420 SEL w/172K miles. Runs like a sewing machine. My great mechanic, (only works on Benz, 30 years now) just replaced a bad spark plug and all the filters. Whoa. I thought it was smooth before. Vibration at 55-65 MPH. Had the front wheels balanced; did not fix it. I did not know of on car balancing or road balancing. That will be done after the track rods on the front end are replaced and of course an alignment. My next task is to paint the roof and rear deck. Oxidation has had its' way. All in all this is a true MB, last of the pure breed. I had a 1972 280 SEL 4.5, one of the best ever. I will get another. The 420 SEL is in the same league; one of the best ever.