350 SL Niggles...

[koksy]

Hi guys this is my first post!

I've recently taken the plunge and purchased a silver 1975 350 SL. Its in beautiful condition having been resprayed and had new leather trim. 83,000 miles which would appear to be genuine from the history file. There are, however, a few niggles with the electrics though.

1) In the middle of the dash, between the heater controls, is a rectangular switch... although the switch is missing from its socket... is this the rear window demist? Can i just buy a new one from my local merc dealership?

2) The heater works (lovely hot air on the move)but the blower has packed up.. either that or its pathetically weak! Is this an easy thing to fix?

3) Call me thick but I can't seem to see where the winsdscreen washer switch is. Are they operated by pushing the end of the indicator stalk? If so they arent working...

A few niggles as i say but bodily the car is A1, sounds beautiful and is totally amazing to drive which far outweighs the problems.

Anybody recommend somebody in Sussex who can sort this stuff out for me so i dont have to go to my local merc dealer?

 

[stats007]

Welcome to the Forum!

John Haynes in Worthing knows just about everything there is to know about R107s - he used to host the R107 Technical Days there for the Mercedes-Benz Owners Club.

I had a 1972 350SL - so answers from memory!

The blower is a weak point - it sits under the heater plenum chamber cover and when the drain holes block water gathers and causes it to seize as well as rust developing - a lot of rust at that. Hopefully you checked all of this before you bought the car?

You can take the cover off and service the motor easily enough - WD40 works temporarily but in my experience they all start to squeak and fail at some point.

The switch sounds like the one for the heated rear screen - I presume the car doesn't have air conditioning? Most parts are readily available - Mervyn Wright down at MB Jacksons in Poole is a 107 parts expert (01202 666330).

The windscreen washer on mine was foot operated - check the driver's footwell it should be obvious if it has one.

They are lovely cars but the tin worm can wreak havoc - worth getting it Waxoyled or similar if it hasn't been already.

Hope this helps.

 

[koksy]

Thankyou so much stats! Will definitely be in touch with John Haynes for maintenance. Its an easy 20 minute train ride and a 5 minute walk home from there for me.

You were right about the screen washer in the footwell!!! I had assumed that the switch was a footrest. Washers work fine. My experience of R107s is limited to friends cars in Cape Town where things like windscreen washers and heaters arent necessary. Have you been? There are 100s of SL's there! I saw one in a garage for sale for £1000 although it was a bit rough...

Regarding the heater, I've never heard the word "plenum" before... the cover that you mention, is it under the bonnet right at the back? I can see the wipers but i cant see the bonnet in that pic which is whats confusing me...

I didn't check for rust under the heater as none of the research that I did online revealed it was a problem (although I knew blowers failing was a common problem). The car doesnt have aircon as far as I know.

The paint job is fantastic. Theres not a single drip or run... in fact it looks like a new car! It has been waxoyled yes. I understand that the guy who did the paint owned his own bodyshop and did it as a hobby but had to sell to expand the business. He's currently respraying the hard top which I wil collect when it's ready.

Would I be able to run it on unleaded? The garage from where I bought it wasn't sure and neither was the previous owner so i'm putting in Castrol Valvemaster plus at the moment just in case.

Heres a pic I took the day I bought her. I've taxed her for 6 months and we'll see how it goes. If she proves unreliable or bankrupts me I'll sell her on. It'll be summer then so I shouldnt have a problem selling.

 

[stats007]

That looks very nice The wheels aren't correct for the year of the car but you'll get a better ride with more modern tyres over the Michelin XWXs (now £200 each).

If you open the bonnet you'll see the cover at the back just below the wipers. The area under here is a MAJOR problem for corrosion - I'm surprised it's not been mentioned before. Some people have lost £1000s on dash-out restoration work because of it so I'd check it out ASAP. The same goes for under all of the carpets, in the boot, soft-top compartment and lower sills.

The only issues I had with mine (apart from corrosion and a leaking roof) were exhaust manifold gaskets going, timing chain tensioner rattling, noisy steering box (early design fault) and heater return valve failing meaning it lost all of it's coolant.

Depending on how it's running a go on a Sun diagnostic machine will highlight any ignition problems - you should have a lovely V8 burble when pulling away .

 

[Thegemmesabogie]

That's a very nice paint job. Later wheels as Andrew says and also a post-facelift (1985) front underbumper spoiler. Both nice upgrades IMHO.

 

[koksy]

Thanks stats I'll check it tomorrow. Fingers crossed! I checked under the carpets but they were covered with insulating foam stuck to the floor. A good prod didnt reveal anything crunching and likewise from underneath. Inside the boot has all been resprayed too nice and shiny. Looking at the receipts that came with it, one of the wings has been replaced at least. I know the alloys were not correct and neither is the front spoiler i beleive? I prefer them to the originals though so I didn't mind.

I picked up the car on saturday morning and drove back down to Brighton at 80mph with no probs. It was a beautiful day so I picked up a (rather amazed) mate and we cruised around town for a while with the top down. Everybody was staring... expecially when they heard the V8 roar when we were pulling away from the lights! I get out of the car almost shaking with adrenalin, even on a short drive to the shops!

 

[stats007]

With regard to running on unleaded - MBs official stance (well the letter they sent me) was that it was OK provided you used a 1 in 4 fill of leaded and a moderate driving style. Failing that get hardened valve seats fitted.

 

[koksy]

Well i got the cover off buut when I tried to undo the bolts holding the blower in, the whole thing just goes round and round including the thread. Is that a bad sign? Surely they must be fixed solid into the metal for you to unscrew them? Took a couple of pics. Doesnt look too bad what I can see. Just surface rust and a bit of dirt. Obviously I can't see under the blower unit though...

 

[stats007]

They are studs, so sounds a bit ominous. Have you tried a hose test on the car?

Spray the nuts with WD40 and leave for a while - you may have to heat the nuts to get them off - personally I'd be curious as to what was on the other side...

 

[Bolide]

There are quite a few good places in Brighton & Hove to look after older Mercedes. Alan Robertson is good for technical stuff and Robin at RJ Engineering is good for servicing & long-term maintenance. They're both in or near the 1st and 2nd Avenue mews in Hove. Thwaites in Portslade is good for MOTs, servicing & tyre fitting and Haynes (in Worthing) is a dyed-in-the-wool Mercedes specialist with proper knowledge of these cars

Nick Froome
www.w124.co.uk