[gwg]

Hi everyone,

I've been on the lookout for a 300SL for quite some time now and using this excellent forum to find guidance.

I came across a late '85 300SL that has been sitting in storage for over 10 years. The owner recently took it out of storage and had a dealer refresh numerous parts (belts, fluids etc.), but I am a little worried about the engine. Some buyer's guides caution against corrosion of the alloy engine with the wrong coolant. Would this worry about corrosion also apply to cars stored long-term? And how would one be able to tell if the engine was corroded?

Many thanks in advance!

 

[ChiefRider]

I believe you are overthinking the problem. While the "green stuff" is not the proper coolant, it's not the ticking time bomb either. As far as how to tell if the alloy block is corroded? Barring major disassembly, you can't. It certainly wouldn't worry me though.

The M103 is a pretty robust engine, and common in the US. The 300SL is a nice variant of the 107, have fun with it!

 

[cwmoser]

I'm no expert but I suspect there is a lot of "myth" about Mercedes yellow coolant.
Two pieces of evidence:
- on the bottles of ordinary green coolant are the words that it is compatible with all engines and colored coolant

- local Indy stated to me that ordinary green coolant is OK

I run the cheaper more readily availble green coolant.

 

[Aussiemerc]

Chief is right- don't worry unless you have overheating problems- the motor is strong.

 

[Fonzi]

And... Isn't the place you should really be concerned about wear or corrosion the cylinder walls? If the cylinders have coolant in them, you've got bigger problems.

Storing an engine with coolant in it... I have to think that it's much less likely to corrode than if it had been going through tons of hot-cold cycles.

What are real storage problems for a 300sl?
- fuel system and distributor getting gunked up with varnish
- brake line fluid taking on water and eating brake hoses
- transmission seals drying up and shrinking?
- any other possibilities anyone can think of??

 

[MBGraham]

And... Isn't the place you should really be concerned about wear or corrosion the cylinder walls? If the cylinders have coolant in them, you've got bigger problems.

Storing an engine with coolant in it... I have to think that it's much less likely to corrode than if it had been going through tons of hot-cold cycles.

What are real storage problems for a 300sl?
- fuel system and distributor getting gunked up with varnish
- brake line fluid taking on water and eating brake hoses
- transmission seals drying up and shrinking?
- any other possibilities anyone can think of??

Tires? Also rubber belts and coolant hoses. All should likely be replaced.

Corrosion increases with temperature. I wouldn't worry about engine corrosion because car has been sitting. But it could be that sludge and gels may have formed in cooling passages. I would at least have cooling system flushed and pressure tested.

 

[MBGraham]

I'm no expert but I suspect there is a lot of "myth" about Mercedes yellow coolant.
Two pieces of evidence:
- on the bottles of ordinary green coolant are the words that it is compatible with all engines and colored coolant

- local Indy stated to me that ordinary green coolant is OK

I run the cheaper more readily availble green coolant.

I don't think it so much myth as lack of understanding of a complex subject.

I am as much at fault as anyone. On my 72 SL and 85 300D, I use the generic green coolant that is sold locally. When I had my SL cooling pump replaced, there was pitting in the thermostat housing that I had to repair with JB Weld. I asked the shop to flush and install Zerex G05, but I did not get a straight answer when I asked if they had done it

As I understand it, the basic green coolant is OK, but the corrosion inhibitors deplete quickly. Therefore should be replaced about every two years.

This link goes into subject at length. For my two newer cars, I only use MB coolant and have it flushed and at regular intervals. (I think MB say 3 years - I need to check when E320 was last done!)

 

[gwg]

Thank you!

Thank you very much for all the very helpful feedback! Seems like I am over-thinking this indeed - the car sitting for 10 years unused just got me worried. But I suppose if most wear items such as belts, hoses etc. (will have to check on the cooling system) have been replaced and it runs well, it shouldn't deter me.

I will have a look at the car this weekend and take it to a local indie to have a look over it for me as well.

Thank you again and I hope to report back with good news.

 

[107merc]

Has anyone tried this stuff?? Home » Evans Cooling Comes highly recommended by my local engine builder.

 

[MBGraham]

Has anyone tried this stuff?? Home » Evans Cooling Comes highly recommended by my local engine builder.

I have not used it. I have read about it and have read some of the company's claims some of which are simply wrong. What seems clear, is that the car will run hotter when using this type of coolant. One thing I would not want, is for my car to run any hotter. Our cars have enough hot-start problems!

An interesting discussion:

Waterless coolant experience

You would think that if waterless coolant was a panacea, new cars would use it. I suppose they could design them that way, but water is still the best heat transfer medium.

 

[107merc]

I think I will give it a try as I have the perfect combo for electrolysis, iron block, alloy head and copper head gasket. Easier than replacing a sacrificial anode every year. Think I will trust Jay Leno's use of the product in all his cars.

 

[gwg]

Thank you again for the advice. I finally got the car this weekend and it's running wonderfully - I took it for a few drives and the temperatures remained at 80 or slightly above no matter what - be it stationary with the A/C on or going at highway speeds for 30 minutes or more.

Very much looking forward to a first road-trip with it.

Here is a picture of it next to my other M103 - a W126 300SE.

 

[SSL]

Thank you again for the advice. I finally got the car this weekend and it's running wonderfully - I took it for a few drives and the temperatures remained at 80 or slightly above no matter what - be it stationary with the A/C on or going at highway speeds for 30 minutes or more.

Very much looking forward to a first road-trip with it.

Here is a picture of it next to my other M103 - a W126 300SE.

gwg,

Signal Red works so well on R107s.

Welcome to the best kept secret of R107 ownership. With updated brakes, suspension, wheels, styling and engine you have a relatively modern and reliable car wrapped up in that wonderfully iconic styling. Given its rarity in the US it might prove to be a shrewd purchase.

I am sure you will enjoy it.

 

[Fonzi]

Did anyone say whether this car is stick or automatic?

 

[gwg]

New car / new seat covers / anyone know a shop in NY?

SSL - Thank you! I'm very much looking forward to the next outing. I'm actually looking through the great advice on this forum on seat covers, as unfortunately the bottoms are really torn up. And I'll have to take care of a couple of smaller paint issues - on the passenger door there is some sort of spiderweb pattern and the car has a couple of tiny rust spots in one wheel arch where it had some chrome covers in the past.

I'm really amazed how well it drives for a car of this age. The seller redid the entire suspension (springs, shock absorbers, bushings, stabiliser rod, ball joints, lower tie rods, center linkage etc.), so that probably has helped a lot.

Fonzi - it's an automatic - I would have loved a manual but both the market (haven't seen any manual show up for sale the last 9 months I was searching) and my wife swayed me towards an automatic.

Does anyone know of a good upholstery shop in NY state to put on new seat covers?

I'm having a hard time deciding between GAHH and TopsOnline, both of which seem to have gotten great reviews.

Best,
George

 

[SSL]

gwg,

Can't help you with your upholsterers as I'm on the other side of the Atlantic!

Definitely get the rust on the wheel arches seen to promptly. Those chrome overlays are often used to disguise rust and these cars, even the post '85 models with galvanised panels, are prone to rust. If you run your fingers alongside the inside of the arches you will notice that the rim folds in on itself creating a perfect shelf for dirt and water to do its worst.

Its always wise to check all the arches. The rears are even more folded.

Looks like your car is well equipped with heated seats, cruise control and climate. It also has something not seen very much on European R107s but very useful; a central armrest.

And of course, best of all, the European fenders. So much better for the overall lines of the car.

 

[rowdie]

gwg,


And of course, best of all, the European fenders. So much better for the overall lines of the car.

Something must be lost in translation. The fenders, or the term we use for fenders, are the same for the US and European models.

 

[SSL]

Something must be lost in translation. The fenders, or the term we use for fenders, are the same for the US and European models.

Thanks rowdie,

Just thought it would be quicker not to use the English term "bumpers" and go direct to fenders.

 

[gwg]

Thank you, I hadn't realised about the fenders being folded in, I'll have a look at that this weekend and maybe already apply some rust remover preventatively. I was planning to sand down and treat a bit of surface rust in the spare wheel well with MercedesSource's Miracle paint this weekend in any case, so I guess my work area has just expanded.

The car has a funny combination of equipment - Cruise Control, heated seats, AC - but then a manual passenger mirror.

gwg,

Can't help you with your upholsterers as I'm on the other side of the Atlantic!

Definitely get the rust on the wheel arches seen to promptly. Those chrome overlays are often used to disguise rust and these cars, even the post '85 models with galvanised panels, are prone to rust. If you run your fingers alongside the inside of the arches you will notice that the rim folds in on itself creating a perfect shelf for dirt and water to do its worst.

Its always wise to check all the arches. The rears are even more folded.

Looks like your car is well equipped with heated seats, cruise control and climate. It also has something not seen very much on European R107s but very useful; a central armrest.

And of course, best of all, the European fenders. So much better for the overall lines of the car.

 

[rowdie]

Thanks rowdie,

Just thought it would be quicker not to use the English term "bumpers" and go direct to fenders.

Which English term? I thought you used wing for what we call fenders. Bumper here is the chrome and rubber piece across the front for collision protection. I am more confused.