[Scholzpdx]

So about a month ago i picked up my first car (that i bought) and it is an 86 420 SEL w/ 187K. Its gold w/ stock rims, near perfect interior and a great body. I haggled down the used car dealer to $925. I LOVE the way this car looks.

So here's what i noticed. The radiator has to be replaced. The hose wont stay in even with JB weld and it has a crack right below where the hose connects. I really doubt it's doing okay. The radiator is not working but i'm not driving it.

When i bought the car it leaked a little oil immediately. The dealer tightend up the engine seals and it hasn't leaked a drop since, so i think i'm doing okay. The oil began to smoke due to the engine running (and no working radiator) and so on the way home it was a smoking mercedes when stopped.

It also has a high idle to the point where i turn it on and i'm at 1600RPM. When I put in into gear from neutral it pauses and jumps for a second. After that the car just seems to fly. I put it in gear and i'm moving already. I'm making no joke about this. If i am not on the brake pretty good it would take a while for it to stop. And i really don't think the brakes are a problem.

The cars alignment is pretty shitty as the wheel shakes going over 50mph. All the tires don't match each other and have only 25-35% tread left; however the car handles and drives very nice.

So here's the deal. I can't find a repair book to save my life. Where can i find this? Also, where can i buy parts for this car on the cheap? Do normal car parts places carry parts on this car?

Also, I could probably buy a 1991 300SEL for $500 (current price is $900). The seller is saying that the engine has a mix of oil and water and they don't have time to fix it. They say that it runs and drives. Would the parts i need be interchangeable? Would it be better to work on that car if i bought it for $500?

I'm willing to learn and do any repair possible.

Thanks in advance.

 

[AxelWulff]

Welcome to the forum and congratulations on your purchase.

While maintenance on these cars is not cheap, the fact that yours has a near perfect interior is a big plus. The most hideously expensive parts are the interior, "beauty", stuff.

High idle is a common problem on cars that have been neglected by their previous owners. Sometimes the solution can be inexpensive, like fixing and easy vacuum leak, and sometimes it takes a lot of detective work and replacing several modules to get it right.
Do a search on "high idle" and read about the various solutions, then work your way through the issue.

Our cars take 4-wheel alignment which most shops can't do. Take your vehicle to the nearest MB shop and have it done there. It shouldn't cost you more than about $100. You may want to have the tires checked and re-balanced before you have the alignment done.

Most repair books are pretty sketchy on the W126 cars. There is a CD set with the MB shop manual available. Not the easiest stack of .PDF files to navigate, but with a little patience you'll get the hang of it.

Aftermarket parts are available for our cars, but the quality is generally quite atrocious and for some parts you really should only use OEM.

A lot of parts from the 300 SEL will be the same as on your 420 SEL. All engine parts will of course be different, but body, chassis, suspension and trim (depending on color) should yield some good replacement parts. Because your interior needs nothing, I'm not sure you'll get your money's worth from the 300.

For parts and the CD manual, call Jonathan Hodgman at (404) 805-1357. He is a full-time W126 enthusiast and a member of this forum.

 

[900$sel]

I just bought mine for $900 haha and it runs great, my only real problem is that the rubber piece that holds the exhaust on broke so now its held on by some metal wire haha. Also there is steering wheel shake but that only around 80mph and it pulls a tad to the right...i hoping this stuff isnt expensive but it was only $900 bucks to how can i complain...

 

[MrBits]

Time will tell

...it was only $900 bucks to how can i complain...

You may learn to find a way - LoL.
I recently logged how my $2K SEC w/ 200K mi. - has morphed into a $7K car, with no R&R on the tranny yet!

@Scholzpdx: Since I had no receipts, the 1st work I had done was to replace timing chain, rails, tensioner, oiler tubes - items generally considered part of the same job & professional labor alone was $500. Should the chain jump-time, common wisdom is that the engine most often becomes an expensive doorstop.

AutohausAZ is where I order most the standard Bosch parts - saves a ton, but still not cheap. A few items I source from eBay too: just ordered 2 Bosch fuel pumps for $95-per... a fraction of retail price! For those who don't wrench on cars yourself, or are ready to try learning, then like me you need to find a good indy mechanic who will let you bring in your own parts. I'm sure this has saved me thousands - versus taking the car to a dealer.

As is often pointed out here on the forum, regardless what you pay for the car, that does not alter the fact that your maintenance is now for an $80K+ vehicle. If ya don't love 'em, you may come to regret 'em.

 

[500SEC_AMG]

I had the same car, same colour, you can fix the rad without buying a new one, trust me on this. I measured the inner circumference of the top tube hole and had the guys at the national research council mill me a tube to slip inside it that was 3 inches long. I used some JB weld type crap and put 2 clamps on and did a 2 month non-stop trip without hassle. it's make the whole a lil smaller but worked with 2 clamps. As for the shimmy make sure the tires are ballanced before you start replacing crap. Best Price Car Parts - Canada | Auto Parts Online Canada, Car Parts, VW, Mercedes, BMW, Part Source is a great place for parts.
As for the high idle, there could be a loose or broken vacuum hose, frig you should email me and we can discuss this car at detail as I dealth with the same shit.
One thing that you should do is go to MB and order 2 meters of vacuum hose, they may have to search for the part but it's cheap and with new boots it will make a huge difference. Also check that the yellowed vacuum tube from the ECU to the engine is not cracked in the slightest, this can cause high idle or stall the car. Email me at [email protected]

 

[billb95]

Congrats and welcome! I'm new to the W126 chassis as well, acquiring my 1986 420sel by trading an old computer system for it about a month ago! It needs quite a bit of work, but with just over 100k miles on the engine, no rust, and a really good solid feel to the car I couldn't resist it. This forum is a gold mine of information and I've used the search feature *many* times.

Good luck with the repairs!

Bill

 

[Teutone]

I just bought mine for $900 haha and it runs great, my only real problem is that the rubber piece that holds the exhaust on broke so now its held on by some metal wire haha. Also there is steering wheel shake but that only around 80mph and it pulls a tad to the right...i hoping this stuff isnt expensive but it was only $900 bucks to how can i complain...

The dealer sells the hangers. The basic rubber donuts never last very long.
For a long term solution. the R107 uses the same design hanger, except it has also woven steel embedded in the rubber.

 

[Daddysflying]

So, Scholtzy...did you ever fix that radiator? I've got the same problem on mine now and I' m wondering if Jake's fix worked.

Other than that, mine is still purring, went to Asheville and back average 19.4 MPG...no complaints...

wendell