Tropical 230SL Woes

[YEOH250SL]

Hello, I have just picked up a 1964 230SL RHD Manual. I live in Malaysia with average weather of 34c/94f with high humidity. I have trouble keeping the car cool on idle in traffic jams. Temp would go up to over 100c/212f. I have recored the radiator, but still couldn't keep the temp down. I'm contemplating of upgrading to a bigger radiator and install a 280SL fan. I also plan to install an after market AC system as soon as I resolve the heating issue. Will those upgrade help? Thanks

[67230SL-Vinny]

Mercedes offered an optional fan shroud to increase air flow for hot climates. Does your car have one?
My 67 230SL was running hot when I brought it to hot Florida. I installed this and problem solved. Never goes over 85C now.

[RAY]

The fan shroud and a 9 bladed fan should definitely go some way to solving the issue.

[YEOH250SL]

Ray and Vinny, thanks for the tip. Do you mind telling where did you source your Shroud from? I hope they fit RHD cars. Also, what type of pump should I get for the 9 blade fan?

[dirkbalter]

Bus Benz makes shrouds at $$$.
https://www.budsbenz.com/catalog/230-250-280-sl/f-cooling/F232-004A
You will need a special 230 fan as it is smaller than the 250/280 fan (or modify it).

[YEOH250SL]

Thanks Dirk. It's $$$ for sure. I wonder what its made of. Metal or plastic?

[Benz Dr.]

Hello, I have just picked up a 1964 230SL RHD Manual. I live in Malaysia with average weather of 34c/94f with high humidity. I have trouble keeping the car cool on idle in traffic jams. Temp would go up to over 100c/212f. I have recored the radiator, but still couldn't keep the temp down. I'm contemplating of upgrading to a bigger radiator and install a 280SL fan. I also plan to install an after market AC system as soon as I resolve the heating issue. Will those upgrade help? Thanks

230SL's should never run hot. Check your ignition system for 8 degrees BTDC all vacuum lines connected. Late ignition timing will make your engine run hot.

Don't expect your engine to run cool with AC installed. I would never put AC in a 230SL.

Try a bottle of water wetter. It works.

[rwmastel]

Don't expect your engine to run cool with AC installed. I would never put AC in a 230SL.

Dan,
He said he's living in AVERAGE conditions of 34c/94f with high humidity there in Malaysia.  I think he needs AC if he's going to drive the 230SL very much.

YEOH250SL,
Why is your username 250SL but you bought a 230SL?     Anyway, shrouds should be plastic.  Be careful buying a shroud for your 230SL, I think the shroud mounting points on a stock 230SL radiator are different than the shroud mounting points on the stock 280SL radiator.  Search these forums and the Tech Manual to see if you can determine if I am right or wrong.  I'm just going off what I think I've read.  Maybe the supplier can send you measurements.

[dirkbalter]

Thanks Dirk. It's $$$ for sure. I wonder what its made of. Metal or plastic?

I guess its metal from Buds B. You can see the weld beats. I would definitely check with them and insure that is fits on a 230 without modifications. I bought and installed their aftermarket AC and had to make some unexpected modifications to make it work or fit correctly. Don't trust the advertisement.
   

[67230SL-Vinny]

Agree with Benz Dr.   

IMHO A 230SL is a sports car. More refined and durable that many of the British, Italian, other German, and American sports cars of the early 60's. Best suited to driving briskly top-down on a twisty with a 4-speed manual and no A/C. Back in the day, a Sport Car with an automatic was...well, you get the picture. Flash forward 60 years and a manual transmission has become a Gen Z anti-theft device.

So, flush the cooling system, replace thermostat, add the fan shroud, check your ignition timing and add a measure of Red-Line Water-Wetter, and call it a beautiful day.

The 280SL is a tad heavier, but with a bit more grunt it handles an automatic and A/C and is better suited to endure hot weather stop & go boulevard driving. Might be best of both worlds. -JMO

Then there's the Mercedes 107 SL's, a lot of car for the Luxury Boulevard set. Wonderful cars, but a 'sports car' not.

Wow, watch me catch flak for this post. But I'm old enough that I can just say it.  -lol   -Vinny

[dirkbalter]

The 280SL is a tad heavier, but with a bit more grunt it handles an automatic and A/C and is better suited to endure hot weather stop & go boulevard driving. Might be best of both worlds. -JMO

Lol, as you already said, opinions are like ****** we all have on. 

However, and without going into details, I think it's a well-known fact that 280is are more sensitive to overheating than the 250/230is.

 

[Benz Dr.]

Lol, as you already said, opinions are like ****** we all have on. 

However, and without going into details, I think it's a well-known fact that 280is are more sensitive to overheating than the 250/230is.

I've entered into this a number of times but our cars were never meant to run with AC. Sedans and coupes using the same engines - larger engine bays give more cooling room. If you have problems with over heating now, AC won't make that problem go away.

[Pawel66]

Are you sure fan clutch is ok and thermostat fully opens?

[dirkbalter]

I've entered into this a number of times but our cars were never meant to run with AC. Sedans and coupes using the same engines - larger engine bays give more cooling room. If you have problems with over heating now, AC won't make that problem go away.

I fully agree with you. Adding AC to a car that has overheating issues will only make matters worse.

I have a 280/Sedan that is way more sensitive to hot (95F and above) temperatures than my sl with a 129 motor. Both have new radiators and similar timing, proper coolant  …..

As to whether or not AC makes sense comes up every couple of month and opinions vary. It all depends on what you use the car for, or in what climate you are actually living. I mentioned that before, if I would be living back in Germany or Canada for that matter, I wouldn’t give it a second thought either. At the same time, if the car is only used to drive to cars and coffee on Saturday mornings or taken out for a ride to the mountains every once in a while, no need for AC either. Personally, I like to drive mine to the office a couple of times a week and use them somewhat regular, in which case AC is a very nice feature to have.  Even though these cars are 50+ years old, I think they are very drivable even in todays traffic. I do respect, but  don’t care about other people’s theories what they should or should not have.

[67230SL-Vinny]

However, and without going into details, I think it's a well-known fact that 280is are more sensitive to overheating than the 250/230is.

Dirkbalter,
You make a good point. Are 280SL's more sensitive to overheating because a much higher percentage were fitted with Automatic and A/C vs. 230SL's that more typically came with manual shift and NO A/C??

In other words, is it inherently the 280SL engine, or is it stuffing the engine bay with more heat generating components that causes the overheating??   For a fair comparison, are manual shift 280SL's without A/C sensitive to overheating??

Just trying to learn something here. And perhaps help the OP as well.

[BobH]

The good Doctor Benz makes a very good point as to why 280's have more of an overheating problem than the other engines

https://www.sl113.org/forums/index.php?topic=5470.0

[dirkbalter]

The good Doctor Benz makes a very good point as to why 280's have more of an overheating problem than the other engines

https://www.sl113.org/forums/index.php?topic=5470.0

Exactly.

[67230SL-Vinny]

Thanks BobH and Dirkbalter,
After reading through the complete 280sl overheating post, I think I learned quite a bit I didn't know. Dr. Benz's final post really summarized that it's a combination of several issues that seem to affect the later 280's, especially with A/C. It is what it is.

Makes me grateful I have a sweet 230SL without A/C. If I want to cool off I drop the top and press down on the go pedal.
Or, if the traffic and high ambient temps look unfavorable, I just take one of my later model MB's with good A/C. 

[doitwright]

The heater core bypass is a common modification for many vehicles with overheating issues. The coolant circuit that feeds the heater inside the cabin is fed from a line off the cylinder head. When the valve to the heater core is closed (as you would expect it to be when trying to achieve a cooler cabin environment) there is no flow from the cylinder head coolant line back to the radiator. Some install an additional crossover line connecting the inlet and outlet line of the heater core in the engine compartment. The factory offered a kit to do this primarily for the 280 engines. Buds may still offer their version of the kit.

I remember Dan explaining that the 230 has a weaker crankshaft than the 250/280 so the added stress of the A/C compressor does it no favors. I can’t testify with certainty, but I believe the current Sander 508 type rotary compressors put much less strain on an engine than the “back-in-the-day” York piston compressors. They are also smaller and don’t need the massive mounting bracket of the York. Regardless, we have seen 230’s with A/C having both compressor types.

[YEOH250SL]

Dan,
He said he's living in AVERAGE conditions of 34c/94f with high humidity there in Malaysia.  I think he needs AC if he's going to drive the 230SL very much.

YEOH250SL,
Why is your username 250SL but you bought a 230SL?     Anyway, shrouds should be plastic.  Be careful buying a shroud for your 230SL, I think the shroud mounting points on a stock 230SL radiator are different than the shroud mounting points on the stock 280SL radiator.  Search these forums and the Tech Manual to see if you can determine if I am right or wrong.  I'm just going off what I think I've read.  Maybe the supplier can send you measurements.

rwmastel,

Thank you for being considerate of the climate. It is excruciating driving in Malaysia without AC. My username is 250SL because when I created the account to post questions, I was prospecting a 250SL, but ended up not buying it. Then several months later, picked up this 230SL

[YEOH250SL]

Dirk,

I know what you mean. I am configurating the AC by buying parts locally. Around this region, aftermarket AC installation is very common. There are many AC parts stores around. We will always try to fit in the largest condenser, compressors, driers etc as possible to battle the weather.

[YEOH250SL]

doitwright, Thanks for the tip, I'm gonna look into that. I actually do not need the heater at all. So I will probably do a heater core delete as well.

[Peter h]

Everything has already been said, but I can confirm it. Whether 230 or 250 or 280, if the engine is operated and adjusted correctly there shouldn't be any major thermal problems. Not even at 34 degrees Celsius.
I also had heat problems at the beginning, but they all had a technical reason and were solved.
Peter