DJNEWK2,

I agree that new parts are not always as they should be, and I would check the thermostat on your car again. The thermostat controls the flow coming from the hot engine (hot water) and directs some or all of it to the radiator. In an MB it also has a side that controls cold water flow from the radiator, and mixes the hot from the engine with cold from the radiator to maintain an even, controlled temperature from one end of the engine to the other. It also avoid thermally stressing the engine in the winter when the car warms up and the thermostat first opens.

So, if the thermostat is not working as it should, it can restrict flow from the radiator. The thermostat housing normally allows flow to the radiator, and when the engine is cold, it offers a bypass route through the thermostat to the water pump inlet, and the thermostat blocks flow from the radiator. This speeds up the warm-up process. When the engine heats up the bypass flow is restricted and the flow from the radiator is enabled. In the cooling system maximum thermal capacity operating mode, the thermostat blocks the bypass line completely and fully enables flow from the radiator, forcing all the coolant from the engine flow through the radiator before returning to the water pump inlet.

If both moving plates in the thermostat are not free to move through their full strokes, it may restrict the return flow from the radiator when, based on coolant temperature it should be enabling greater flow of cooled water from the radiator. Or, it may always allow bypass flow. In either case the hot water going into the radiator at the top will be nice and cool, or at ambient anyway, at the bottom of the radiator as it slowly makes its way to the outlet.

There should be a thermal gradient from top to bottom (inlet to outlet) anyway (or you are not removing any heat), so a cooler bottom (outlet) of the radiator is perfectly ok and by itself not a sign of something being amiss.

Good luck with the issue. Many have struggled and in other threads on the subject, changing viscous fan clutches and/or thermostats seem to help. Jim

edited for clarity

Since I've changed the expansion tank, it no longer leaks around the base of the cap anymore...it now leaks from the overflow in the fenderwell. So the radiator SHOULD have cool spots on the fins? :confused:

When I did the hot water test on mine it was the same hottness all over. For the time it would take - I'd do the test and confirm or eliminate the rad as a culprit.

tkamiya,

I am not familiar with the location of the overflow tank, and any provisions the system has for venting when the pressure rating of the cap is exceeded. I figure it is possible to lift that cap just on temperature alone if you see a rapid increase in temperature indication that goes near the red zone.

The indicator on the dash has a lag time and it not sensing the highest temperature in the engine. So, it is feasible that the pressure in the system is near or at the cap's relief set point.

Overall the cooling system is pretty complex. Our interactions with it, as owners and maintaining it, are pretty limited, by design. Checking the cap is good idea though as the loss of pressure will eventually lead to loss of coolant and then serious overheating. Jim

my 190 e which has a 1.8 litre engine used to run hot in traffic and at idling,the temp gauge would creep up to 120 degees on the temperature gauge.--my engine has an electro-magnetic clutch type fan which is supposed to cut in at 95 degrees if working properly-i replaced the cooling fan switch which is on the cylinder head and this has solved the problem and normal gauge behaviour has returned.

do the 560 engines have an electromagnetic type auxiliary cooling fan-if so irt would be worth checking the cooling fan switch out.

the only other time i have seen a bmw 525 overheat like yours is when the t-stat snapped shut and another time an audi ,5cylinder ,in which the radiator core was blocked-changing the radiator cured it.the odd thing was the radiator appeared totally normal from the outside but the inner tubes were blocked.
a

DKNEWK2, and moedip,

The radiator works by spreading the hot water out over a relatively large surface area of a thin metal barrier that has a surface area enhancement treatment, fins or a corrugated metal filler between water channels, to maximize contact with air. The air is heated by the transfer of heat in the water that in turn heats the metal of the fins or corrugated stuff.

The hottest water in the radiator is at the inlet from the engine, and the coolest water in the radiator is at the outlet. If the flow rate is very slow, the water will spend enough time in the radiator to reach a temperature approaching that of the air when it reaches the outlet. So that will give you a thermal gradient of hot to cool from one end of the radiator to the other. If there is not thermal gradient, the system is not working. You might as well replace the radiator with a short hose.

The test moedip described flows water into the radiator faster than the normal coolant flow rate. If, under those conditions you see a hot and cold spot, it will most likely be from the flow pattern (all the flow going in one area instead of over the whole radiator or being excluded from a couple of areas). The flow pattern abnormalities can be due to restrictions from junk collecting or chemical deposits, like hardening of the arteries, in the water passages in the radiator, or pinches in the coolant passages. Since the flow is not prototypical the results must be interpreted carefully. You should give a few seconds to let air vent and so on.

In any case, the moedip test quickly fills the inside of the radiator with hot water, and before it can give up a significant amount of energy to the air, you can feel the distribution of flow as areas of the radiator that are warm. Warmer areas have had more hot water flow by, and cooler areas less. I would still expect the water that entered first and ended up travelling farthest in the radiator to be cooler than the hot water entering last.

I hope that helps. Jim

If temp runs OK at speed, this would appear to mean the radiator is working effectively enough to keep temperature at minimum (tstat tries to keep a minimum temp, right?) ... so, how can it be the radiator?

Have you changed the tstat? If not, give it a try ... what do you have to lose?

Hey guys...its been a long time and I've been outta town unable to get to my baby until day before yesterday. Well, I changed out the thermostat (with the bleeder valve at the top/right position like the old one that looked pretty good mind you) and took her on the road.ONCE AGAIN, 80-82 degrees around town for about 15 minutes but when I got her on the highway and exited, 110+! I've also had it tested for pressure and its okay so far. Today on the way to work, the same thing but now she stays at 100+ on the highway. I'm wondering if I should replace this "new" radiator with the old one I kept to see what happens because other than the broken neck, the car still ran at 80-82.

Another question I have is: Is the fan supposed to be able to spin freely when you shut the car off? I ask because on some of my other cars I've had, the fan doesn't move at all unless the motor's running. I was able to move the fan freely as I felt around the radiator after shutoff which revealed the radiator being very cool on the right side (facing car) and then hot as hell when running my hand toward the left side by the hose. Also, when I had the car running, I'd squeeze the upper hose to see if I could feel water rushing through and did not feel it at all. The top of the radiator is also hot to the touch.Is this a matter of the radiator being clogged and what could clog it this fast (its only been in the car a little under a year) ?

I'm wondering if I should change out the pump although there is no leaking or squeaking/noises. Would it be safe to replace that old radiator with a broken neck in order to have my other one checked or should I just suck it up and replace it (again but with a Behr)? Any help is appreciated and thanks for the replies so far in my plight to correct this.

DJNEWK2:

I'm not going to pretend that I've digested every word of this thread - actually - I've read little except for a couple of posts you've made on page 4.

You mentioned some spots on the radiator being cooler than others. You mentioned temps were ok B4 changing out the radiator - you changed because of a broken neck.

Seems to me the radiator might be the problem. Is it a Behr? I personally wouldn't use any other brand. If the neck is just cracked in a spot, but will still hold a hose, try reinstalling the old radiator and see what happens. I'm not suggesting this as a permanent solution, but if the old unit is usable for a "test", why not give it a try?

I too had an overflow out the expansion tank problem. Thought it was the t-stat. Changed it. Still overflowing. Turned out to be a weak seam in the tank - wasn't holding pressure. I realize that you may have addressed this already - again - haven't read every word in this 4 page thread.

My 2 cents.

I would definately only use this as a test...I was just wondering why a perfectly good and functioning radiator would all of a sudden fail unless it got clogged while draining it and refilling it? Who knows, but this whole thing is driving me nuts:(

Thanks

Alan

If you are thinkng of trying the rad substitution test - go half way - pull your rad and fill with hot water as I suggested previously and feel for cold spots. Do the same on the other rad - if the other rad doesn't have cold spots - buy a new rad or get it cleaned. It would be simpler than taking out installing and taking out and installing again.
Just my thoughts
Maurice

Flushed the radiator last night and noticed that is was pretty clogged with little white particles inside on one side and had some feathers in the fins that washed right out...I also reverse flushed and found that it was flowing well when I finished. I reinstalled and ran water into the hose from the bottom to see if it would flow out of the top outlet which it did. All was cool (I thought) but when I filled the upper hose inlet going to the water pump, the water didn't go down and just sat there and got hot.

Shouldn't that water go down to be circulated back to the radiator? Then I heard the water pump squeaking for a few seconds and then it stopped, but as I said, the water just stayed in the hose and started to get hot and no water came out of the upper radiator outlet. So far she's run at a fluctuating 82-100 and no coolant loss. Does 100% water make the engine run warmer or cooler? I thought it was cooler but not sure. I haven't added AF because I've already wasted one container of MB coolant since the t stat change and want to save the other until I've licked this. Does this sound like the water pump or ??? Would it take almost 20 minutes (like it did this morning) for the temp to go past 100 if it was the water pump? Man oh man what's next!?:confused:

Take the rad to a Rad Shop and get it professionally cleaned and checked - I really think that will solve your problem. There are many raceways for the water to go from the bottom to the top -if some of them are plugged - water will still flow - but you will still run hot - save your aggrevation - get a pro to clean the rad and guarantee it is clog free. I am confident it will cure your heating problem.

I agree Moe and that is next on the list... I've been trying to locate a behr radiator at a decent price because I believe them to be a better constructed radiator than the Nissens I have.Also, what about the water pump issue? Any opinions welcome. The radiator shops I've called so far say they can't clean it because they can't take it apart (but I'm sure SOMEONE can take it apart) so I'll have to just keep trying...Thanks for the advice so far and feel free to keep em coming!;)

I'd leave the water pump for now. When you get the heating problem fixed - add some water pump lubricant to the antifreeze and it will stop the squeal. If the pump was bad - you'd have overheating all the time (worn out vanes - broken vanes would be clanking in pump) or it would be leaking - so I'd leave the pump and get the rad done.The chemicals they sell for DIY are not strong enough for real bad clogs. If they say they can't clean it because they can't take the top and bottom off to rod it - look for another shop - up here in no-man's land - there are shops that have the gaskets and expertise to remove the top and bottom plastic covers and replace them - there must be one down there. Be advised that it might be cheaper to buy a new rad then pay what some of these rad guys want for cleaning. I checked out the price for my 1930 Chevy rad CORE ONLY - not soldered to the top or bottom pieces - $500-700 USD! Mercedes is sounding cheap for rad prices now!!:p :p :p

Believe it or not I actually found a NEW Behr for $219.95! Hopefully I will get time to be able to put the original radiator on her before the weekend so I can see how she acts and if all is well, definately get the new Behr that the dealer says should be here from Florida in 2 days tops for $10-$11 shipping. Hell I paid damn near this much for the Nissens I have ( I should buy two-- this guy doesn't know if it has the reinforced neck but whatever...the place I bought my Behr from for my other 560 that's sold by the way is history)! Man I'm hoping this isn't a head gasket (even if its a small leak not detected before) but there's no water in oil and no oil in coolant so God is looking out for me on this one.

DJNEWK2:

A few days ago someone posted here that the new Behr's do not contain the reinforced neck. I see you picked up a new radiator for just over $200. Not long ago the reinforced models were closer to $300.

Please post back here whether this $219 rad. came with a reinforced neck. Thanks.

Will do, but at this point I'm thinking it took 14 years for my original's neck to break so if it isn't I'll live considering I've only had the Nissens about a year and already have issues (if it is the case). The old Behr still works fine and I can actually hook up the hose to it but not as secure as when the neck is how its supposed to be.

I took the car out for lunch and so far its running at temp 80-84 in town but very erratic shaking at takeoff smoothing out as I get speed (but still crappy gas mileage). Wouldn't a leaking head gasket also cause rough running? If the radiator swap doesn't work that will be what I'll have checked (again just in case its acted up from the high/low temps). Just paranoid right now because I hate not having it definately pinned down yet. thanks a lot guys

Alan

a couple of times you've mentioned that the aux fans kick in at high temp but you always say you switch it off then - what happens if you let it run? the high speed fans should cool it down then eventually switch off. they should already be on by the time you hit 110C. if you switch off then the heat soaked engine has nothing to draw off the heat and the temps will climb even higher and possibly cause the release by the pressure caps in the overflow tanks. if you have plain water in there, it will be easy to cause this as the boiling point is lower. i did see that you mention that coolant makes it bubble over more easily which is the opposite of what i expected. i would tend to suspect the themosensor that triggers the high speed fans. i believe they should come on before 110C at which point temps should start dropping rapidly...

I started reading this thread and couldn't stop. I will refrain from offering advice - you have plenty of that. But the whole issue started when you went from water to 50-50. Here is a possible explanation from the Red Line (make Water Wetter) web site.

Good luck!

"Red Line WaterWetter® can reduce cooling system temperatures compared to glycol solutions and even plain water. Water has excellent heat transfer properties in its liquid state, but very high surface tension makes it difficult to release water vapor from the metal surface. Under heavy load conditions, much of the heat in the cylinder head is transferred by localized boiling at hot spots, even though the bulk of the cooling solution is below the boiling point. Red Line's unique WaterWetter® reduces the surface tension of water by a factor of two, which means that much smaller vapor bubbles will be formed. Vapor bubbles on the metal surface create an insulating layer which impedes heat transfer. Releasing these vapor bubbles from the metal surface can improve the heat transfer properties in this localized boiling region by as much as 15% as shown in Figure 2. This figure demonstrates the removal of heat from an aluminum bar at 304°F by quenching the bar in different coolants at 214°F under 15 psi pressure. Compare the time required to reduce the temperature of the aluminum to 250°F, or the boiling point of water at 15 psi. WaterWetter® required 3.2 seconds, water alone 3.7 sec, 50/50 glycol in water required 10.2 sec, and 100% glycol required 21 sec. Water alone required 15% longer, 50/50 glycol 220% longer, and 100% glycol required 550% longer."

yea the aux fan kicks in like its supposed to.I was saying that when you shut off the car, the fan also stops so I shut the car down and then turn the key back on so that the fan continues to blow until its below 106 stopping the fan. Now I always do that if it kicks in and leave it on and lock the car with the other keys (returning about 5-10 min after the heat dissipates to get my key out).

I've also used the water wetter to no avail (back then when it was boiling and spitting the coolant back out but now the coolant stays put for the time being since I changed out the expansion tank,hose and cap). I'm wondering if anyone is familiar with where the coolant holes are on the block if these have them.Someone on an earlier post says it could be air trapped and I don't think their was a 560 so this may not apply to my car.Also need the location of the exhaust valve on this car (for something else). Thanks

Alan

DJNEWK2:

I too have a 126 gas car, but with the smaller 6 cyl engine. I recently resolved an air-in-cooling system problem following some advise I found in a post from back when. The process applied to a 124 car, but it has essentailly the same engine as mine. I cannot say if this will help a 560. Perhaps those versed in this engine will add to what I have here. Here's what I did:

- Start out on level surface with a cool engine.
- Remove expansion tank cap and top off coolant if necessary. Leave cap off.
- Start car. Let it idle. Monitor level in expansion tank. If it starts to boil up, etc., shutoff engine. This happens on some Asian models when you try to "air bleed" them. Didn't happen on my Benz.
- After about 15 mins., I saw coolant level rise up a bit. At that point, I turned on the heater to allow complete circulation. Let it idle another 15 mins. with heater on. Coolant rose just a bit more, but never bubbled or boiled out. I allowed car to idle for a total of 30 mins.
- I suspect the air was forced out as the coolant rose.

Maybe this will help your situation.

alan,

okay, i understand what you meant, but are saying that when the aux fans are on and the engine is running, it doesn't cool down? also, i would think the cut out point should at least be below 100C. in the m104 engines 106C is when fans cuts in. i had a crazy overheating problem like yours more than 20 yrs ago with a mitsubishi four banger. when it was running normal, everything was fine but when it ran hotter it quickly went into an overheated state from which there was no recovering. my mechanic opened up the head for a look see (easy in those simpler designs) and saw that it had higher compression dome head pistons which was a late model changeover. the higher compression sorta explained the higher temps and to make a long story short i finally went and got an oversize radiator. that took care of that. my point is that your description of the overheating behaviour reminds me of that case and maybe your radiator is indeed plugged up and not providing sufficient cooling. BTW, remanufactured Behrs are available for about $125 - could save you some money. (resedaradiators.com)

DJNEWK2,

I am not trying to add more rain to your parade, but I've had a very similar problem with my off-topic 96 Lincoln Town Car (i didn't have this problem with my benzes...yet...). It began overheating a little bit at first, I was going nuts trying to figure out what was going on. I didn't overhead badly and only did it occasionally and was running like that for months until about 3 weeks ago. It was about 95 degrees outside and I was in traffic when temperature shot up to the max. I let it cool down, then restarted again and drove it back home - temps were OK. Then a day later - temp back to the max. I said enough, went driving to the shop - when I arrived, temps were close to the max, I suspected anything but headgasket (because I was checking both the coolant and the oil - no signs of any leakage were present), but on my final drive to the shop I noticed roughness on take off. In any case, after checking compression - it was the head gasket. So draw your own conclusions, just a story here to add to your deliberations, better safe than sorry (warped heads and all).

head gasket failures on benz engines typically manifest as external oil leaks. by the time it reaches a point where there is loss of compression through there i would venture to say that the head is already warped from overheating. i had the well known head gasket failure on the m104 and i had neither power loss from compression, nor overheating - just a really annoying oil leak...

I think this plug is in the coolant circuit. It located on the right head at the back at the firewall. This engine is upside down so rotate your head appropriately.

Other coolant plugs / drains.

The other side

Thanks guys! I actually think I've finally nipped the temp issue...I've replaced the radiator with the new Behr and refilled her with a gallon of MB coolant and remainder with water. Took her on the road last night and ran the hell out of her.80-82 steady. Had the defroster on hot/max and pulled her into the driveway and topped her off and took her back out. Again, 80-82 degree temp and burning hot heat blowing.

Took her around the block with the A/C on and temps steady.This morning brought her in to work with no problems and the REAL test will be in the stagnant traffic with 90+ outside temp which I think will be no problem for her but we'll see. I popped the hood when I got in this morning and all of the coolant is in the tank, and I could even open the cap without boilover which was awesome! I don't think I needed to replace the thermostat but I'm glad I did (and I kept the old one anyway so...). Seems like my baby's back to her old self again. I also put new Beru wires on her which has greatly improved the throttle response and eliminated the rough idle she's had lately. Again, thanks for the advice. Next project is to replace the front brake pads this weekend, and I'm waiting on my THREE sets of euro headlights to come through customs in 2 weeks to be installed! Whooooa!:D

Alan

DJNEWK2,

So, you replaced the radiator and the thermostat at the same time? Aaacckkk .... if you did, we all may have missed the opportunity to see which one was the problem ...

I had been "betting" it was the tstat since you noted earlier it had a replacement radiator in it.

Can you fill us in on this?

No I replaced the t-stat a few weeks ago thinking that would solve it but it didn't. I only replaced the radiator last night. I'm keeping the Nissens because its not even a year old and get the particles that gathered in it professionally cleaned out. I always wanted to put a Behr in her anyway and I got this one new for the same price as the cheap Nissens with reinforced necks to boot!

It would have cool spots on one side and although I was getting close to lowering the temps at times, it would climb once I got her off of the highway it would shoot up and every so often it would come down a bit but not much below 100 so the aux fans would dang near always have to work. So far the 45-55 mix I've got right now works best for her (knock on wood) will keep ya posted.

Thanks for the follow-up ... great to know that it was radiator and not tstat ... this will likely help someone else as they troubleshoot their problems using this thread!

I have had overheating gremlins before and I though they were gonna drive me nuts ... it is probably a great relief for you to be able hammer it and then cruise in hot traffic with confidence!

BTW, one of the side effects I noticed after replacing my tstat was that it seemed to warm up faster than before ... have you had the same experience?

I actually didn't really notice a difference because it would always warm up within a good quarter mile or less before which is why I didn't think anything was wrong with the t-stat. That's one good thing I like about the car is that when its cold as crap outside, it would have nice heat (along with the heated seats) in no time.

OK Alan, you've had a couple days, and if your weather has been anything like our it is hotter than all get out. So what's the verdict, is it fixed????

yeah, we're all waiting. my bet was on a plugged radiator...

Hello fellas!
To update everyone on the final verdict (as Mike T would put it), my baby's dong just fine and it has been doing constant 80-82 degrees with or without the A/C running in the 90+ degree heat out here. I figured it had to be the radiator too and thanks to everyone for their input.

The highest the temp has gone was yesterday on an infamous road (Roswell to those in Atlanta) where you barely move an inch a minute to get back to the interstate.The fiance and I were meeting at a restaurant to exchange cars (because her mom and her aunt and cousin came down to look at wedding dresses and go to the bridal shows this weekend and her little convertible was unbearable and she needed the "limo").

She reached about 88 or a bit over and the aux fans didn't even have to kick in! Once I got going and traffic let up she was back down to 80-82 within a few seconds...So as of now the high temp saga has finally ended and the "squashed passenger saga was over for my fiance and future in-laws thanks to the "limo" who showed them all comfortable (and roomy) southern hospitality. :) Once again, thanks guys for all of the advice and hopefully the next project (my euro light conversion ) will be another pleasant ending! By the way Mike, did you get to see Ashman's euros? Mine are awesome and I've still got an extra set available that I may end up giving up.

Alan

No Alan, didn't get to check out Ashman's, but did get to check out Placo1's. I think his were DEPO's, nice clear glass and bright reflectors. A set or euros would look just right on the 560.

Actually Placo1's are Hella 500E euro lights.

The DEPO's that Alon has look exactly like the Bosch euro's that I have installed on mine.

Great News!

A great thread as we covered about EVERYTHING ... someone will be very thankful with their problem in the future.

Yea tell me about it...I was going crazy about what it could possibly be. I thought it was the radiator but didn't want to accept it because it was still "new" so I guess the advice I would give anyone is "just because its new doesn't mean it can't screw up" :) Mike, how's the 560 doing anyway? I kinda miss it...you need to post a pic of the Blitzen mobile in its current state dude!

Hopefully I'll be putting up a 126 euro light conversion story together complete with pictures soon. I've gotta get my hands on a pretty good digital camera because I know I'll just have ANOTHER roll of film to get developed if I don't. I think I still have pictures of the 1996 Olympics that I haven't even developed yet:eek:

I've noticed that my blower motor fuse blows a lot and has even melted the bottom portion of the fuse holder so that I have to keep a piece of a broken fuse down in the hole where the connector should be to make a connection with the bottom and the top of the fuse. This was a problem when I got her and its just burning further and further down.

I want to replace the fuse with an independent 30 amp blade type fuse and wire it directly from the blower motor. Any ideas or is it a better way of avoiding this? I wonder if I have to replace the WHOLE fusebox with new connectors or am I able to take sections of the fusebox out and replace? I noticed that after 1986 the blower motor's fuse is located in a separate space other than under the fusebox door like the rest of them.Is this a reason for this or what? Just wondering before I take matters into my own hands.I really don't want to "rig" this,but she's blowing the fuses (25 amp) a lot and the smell of the burning comes through the vents when its about to blow---getting on my nerves. Thanks.

Alan

P.S. I shouldv'e just started another thread with this one huh?;)

Alan,

Look in the "other book", you'll find a blower fuse conversion kit for something like $29.00. Supposed to be for moving the blower fuse out of the fuse box on '86 models and bumping to a 30 amp.

Let me know if you can't find it.

Really? the book I gave you? Don't tell me I missed that! What page/section is it in? I don't have my replacement "book"here with me but maybe I can get a part number or something if they sell it here at partsshop. Thanks

Alan

Pages 58/59, item #25 $29.79.

Of course I rushed home last night and found that part and I'm thinking it must have been a problem.Thanks for the heads up Mike!

Boy it sure is hot
 

I had a 89 56-SEL that was running hot just as you described. Cooled great in town with A/C on (aux fans running, low heat load to dissipate), heated up on freeway in hot weather, then shot up on slowing down. Pulled the radiator and had it rodded out (shop that could remove and replace tanks) and solved the problem completely it ran at 85C.

Cause? Antifreeze additives salting out of solution from previous owner running it too long.

Your case --- incompatible antifreeze read the fine print. If you are using the 'green' stuff or MBZ stuff, you MUST completely flush it all out before switching to 'the orange' stuff. The two are incompatible and will plug up the radiator if even slight cross contamination. Cleaning agents will not remove it. Only recourse is mechanical rodding or replace the radiator.

Replaced both the 500E and 360TE AMG viscous fans with electric puller fans from Spal (16-inch) using Derale adjustable thermostats.

:-) neil
1988 360TE AMG
1993 500E

http://www.silcom.com/~neilv/sportli...3-mounting.jpg
http://www.silcom.com/~neilv/sportli...-connector.jpg
http://www.silcom.com/~neilv/sportli...-waterpump.jpg
http://www.silcom.com/~neilv/sportli...ler2-probe.jpg
http://www.silcom.com/~neilv/sportli...04-puller1.jpg
http://www.silcom.com/~neilv/sportli...-enginetop.jpg

Good looking job and thanks for the pics. Do you have links to the vendors you mentioned? Did you use sheetmetal fasteners to bolt the new fan brackets up to the radiator?
thanks

The fan is a SPAL 16-inch puller fan, their high-speed version, pulls 2300+ CFM. Get it from BeCool because they include the best brackets. The brackets are attached to the radiator via 4mm nuts-and-bolts, with washers, lockwasher, and "blue" Locktite threadlocker.

I used a 6-position MB headlight connector assembly because I had many in stock along with 10-gauge wire.

The adjustable thermostat is from Derale, and uses external BOSCH-type relays.

The fan is secured to the radiator in 4-position. I used two existing holes in the radiator, and drilled two others- never touching the core. Because the mounting brackets were SHORT, I could not use the other two exisiting holes on the radiator.

The sensor is inserted fairly close to the water inlet for more accurate temps. and I used heat-sink compound from Radio Shack to make sure the meta-to-metal heat-interface is good.
Better late than never . . .

Here are more pics of the SPAL 16-inch puller fan on the 500E. Pictures are with and without shroud, and the Derale thermostat relay.

Yes, the puller fan is NOT centered to the shroud, because it will INTERFERE with the waterpump pulley.

Enjoy,
:-) neil
1988 360TE AMG
1993 500E

http://www.silcom.com/~neilv/sportli...19-puller1.jpg
http://www.silcom.com/~neilv/sportli...er2-shroud.jpg
http://www.silcom.com/~neilv/sportli...thermostat.jpg