Oil Cooler Calamity

[PeterW113]

In hindsight, I have perhaps foolishly put the oil cooler through the dishwasher. The outside looks perfect, but I am now beginning to realise that it probably wasn’t a good idea for the inside and ultimately the engine. 

I have since flushed it through with petrol, perhaps also not a good idea, and plan to flush it through with clean oil.

Before I do so and refit are there any suggestions as to any other precautions I should take?

Your informed opinions are valued as always.

Peter

[Benz Dr.]

This might require some translation. What exactly does putting something through the dishwasher mean?  If you blasted it with sand and didn't close the ports off that would be bad indeed but fluids or solvents shouldn't hurt it as it can be blown out.
The worst thing that can happen is when you blow an engine but neglect to properly clean the oil cooler inside of any small shards.  That will surely make your day.

[Garry]

Dan,


Some lucky husbands have a wife who lets then use the parts cleaning system they have in the Kitchen.  Some wives would tear you to shreds if you used their parts cleaning system.  Others, who are really brave, don’t even tell their wives that they used the parts cleaning system at some point

My wife complains that our dishwasher makes that low rumble that is distinctly a Pagoda!!!!

[PeterW113]

Yes guilty as charged I put it in the Kitchen dishwasher without telling my wife.

My wife has since been complaining that the glassware seems to come out a little smearey.
 

[Bonnyboy]

You are probably out of Jet Dry   

You may try running a load using "Gojo Orange hand cleaner as well as soap through a full cycle  -  It really cleaned our dishwasher well after I cleaned the engine cases on my Triumph.   My wife still doesn't know. 

[wjsvb ✝︎]

Maybe we need a new thread here: 1) best brands of dish soap for various jobs, 2) What works best on dirty reusable oil filters, 3) Proper placing of parts for maximum cleaning, 3) Best excuses for when caught, 4) How to gain needed kitchen room by relocating dishwasher to garage.

[PeterW113]

Judging by the well recieved good humour I may be over thinking this. The operating temperature of the Dishwasher is far less than the engne and, any grudge dislodged by the detergent should be dealt with by the flushing mentioned earlier.

In theory any thing left will be picked up by the oil filter which is next in line. I wll be doing an oil change once everything is reinstalled (including new flexi hoses) so fingers crossed I should be OK.

Thanks as always.

P

[Shvegel]

Peter,
If you still have the original hoses with the aluminum sleeves on the end the ends are reusable.  You can just replace the hose for that “correct” look. If you decide to replace the hoses and ends with newer crimped on ends I would hand on to the old hoses.  I have a feeling little things like that might become valuable as the value of our cars continue to rise.

[mbzse]

.../... oil cooler through the dishwasher. The outside looks perfect, but I am now beginning to realise that it probably wasn’t a good idea for the inside.../...

Probably no problem. However, later on the oil coolers offered by M-B and other vendors for a 280SL (M130 engine) are made from aluminium alloy.
The dishwasher detergent is quite basic (has high pH value ) so it may corrode the metal in those later type coolers.
See this video: https://www.youtube.com/watch?v=FFkv0vwRsGg

[ejboyd5]

If one were to put an oil cooler through a dishwasher, how much soap and water would you expect to actually enter the cooling passages?  Worries about entrained water and detergent corrosion are exaggerated and baseless.  Blow the passages clear with some compressed air and get on with the installation. 
By the way, unless you operate in an extremely hot climate or subject the car to endurance tests, isn't the oil cooler an unnecessary piece that actually prevents the oil from ever reaching optimal operating temperature.  For example, with a 300 SL in road service, most owners bypass the oil cooler so that water and oil temperatures stabilize at approximately 180 degrees.  What oil temperature would you expect a Pagoda to reach with an operational cooler; probably nowhere high enough to serve efficiently.  You might best be served to replace the cooler for appearances, but bypass it to raise your oil temperature.

[Benz Dr.]

The oil cooler on a 280SL is steel. Aluminium was used in later coolers such as 123 diesels.

 A 300SL holds 12 liters of oil and getting it hot enough to remove any fuel vapors is kind of important. I bought a plate that fitted in front of the cooler in early spring weather just to get the oil up to operating temperature.

 You need an oil cooler on a 280SL because those engines run hot and you need all of the cooling assistance you can get.

[ja17]

Yes, the oil coolers on the 280 SLs are steel and will rust out from road salts. Some 6cyl W108 sedans used the same oil cooler. The W108 V-8 sedan used a nice aluminum oil cooler which is the same size as the 280SL but it is mounted on the opposite side of it's radiator. This aluminum cooler would fit in a 280SL but after mounting it on the correct side for a 280SL, the drain plug would be on the top!

[Iconic]

My original steel oil cooler had corrosion holes in it and I could not find anyone to repair it.
The replacement was purchased from the MB Classic Center about 7 years ago.
It came in looking the same as the old one ... except the core was aluminum instead of steel.
Oh wait, that beautiful aluminum cooler is gone, ... sold with my old Anthracite Pagode.
I'm sure I'm back to steel with my "new" Pagode.
It seems to be dry thank goodness.

[ejboyd5]

You need an oil cooler on a 280SL because those engines run hot and you need all of the cooling assistance you can get.

Interesting opinion, but is it supportable.  M-B had a long history of designing its vehicles for the worst conditions, not ones encountered by the average driver.  The oil cooler is a perfect example of this over engineering that in daily use keeps oil temperatures too low.  Can anyone supply long term data on actual oil temperatures in Pagodas? 

[66andBlue]

....
By the way, unless you operate in an extremely hot climate or subject the car to endurance tests, isn't the oil cooler an unnecessary piece that actually prevents the oil from ever reaching optimal operating temperature.  For example, with a 300 SL in road service, most owners bypass the oil cooler so that water and oil temperatures stabilize at approximately 180 degrees.  What oil temperature would you expect a Pagoda to reach with an operational cooler; probably nowhere high enough to serve efficiently.  ....

Can you explain, please, what YOU consider the optimal oil temperature for our cars should be? And based on what?
I thought that Mother Daimler or perhaps Papa Uhlenhaut would have known best. 

[PeterW113]

Mine is definitely made of steel, it’s pretty heavy and was made by Behr which I guess is the Oem.

Externally it looks in good shape, no holes, it’s been thoroughly flushed through now with degreaser followed by fresh water and spent the last 24 hours or so drying out in the Boiler Cupboard. I will further flush through with clean oil.

As for the hoses, I have already ordered new ones from SLS in Germany, but will keep the original alloy sleeves ones for the future.

Best

Peter

[ejboyd5]

As to exact temperatures, you'll get as many answers as responses.  Generally 180 degrees would be considered a minimum and 230/240 degrees a maximum that does not stress the oil's capabilities.  The important thing is to get the oil hot enough to boil off water and other liquid undesirables.  Mercedes-Benz engineers did a fine job preparing their cars to exist in what today would be considered extreme conditions.  For the average driver an oil cooler makes it difficult or impossible for the oil to get warm enough to be cleansed.  Once your engine has normalized, shoot for an oil temperature that is 20/30 degrees higher that the water temperature.

In a prior post, Benz Dr. mentioned that a 300 SL holds 12 liters of oil.  Actually, the maximum is 15 liters with 12 liters being a recommended minimum. Most owners today have bypassed their oil coolers and run 9-10 quarts of oil to assure oil temperatures high enough to boil off diluting substances.  M-B states that oil temperatures of 230/240 degrees "are within the range permissible." 

[ja17]

My first Mercedes Rally Car had a M130 engine.  I installed an oil temperature gauge.  It was always interesting to study what and when the oil temperature changed. The oil temperature took some time to reach the water temperature (180 F). It usually lagged behind the water temperature.  Higher rpms radically and quickly increased oil temperature to over 200 F  and seem to make no or little change in water temperature. One surprise was certain oil brands seem to generate higher oil temperatures ?

[66andBlue]

Joe,
were did you install the gauge, at the oil pan or the block? I am told that there is a 20 ℉ difference, correct?

I was thinking that perhaps one of these gadgets might be quite useful. Even better would be a wireless one.
https://www.summitracing.com/parts/vdo-323-055/overview/

[mbzse]

.../...original steel oil cooler.../...
The replacement was purchased from the MB Classic Center about 7 years ago.
It came in looking the same as the old one ... except the core was aluminum instead of steel.../...

You are right, this is so. Hence my posting on alu cooler (I have now adjusted the text in that post); I exchanged mine just like you. Forgot about the change of construction material

[ja17]

Alfred,
I welded a fitting in the side of steel sub-oil-pan. Then I just screwed the sender bulb into it, from the gauge.

[Tom in seattle]

I'm interested in this discussion because the 250 SL I acquired had an oil cooler but was disconnected.  Having read that the 250 was an attempt to increase power but the water jacket resulting from over boring the 230 block resulted in overheating without the oil cooler.  So one was added.  My cooler, now plumbed in, is copper.  In a 90f day without the cooler plumbed in the water temp would approach redline on the dash gauge.  With it properly fitted, water temp is 200f at any day.  Obviously I'm happy. 

Is the 250 oil cooler a different design and material than the 280?  Would the 280 overheat without its oil cooler?

[Benz Dr.]

250SL is the same bore as a 230SL only it has a longer stroke. The 250SL oil cooler is actually a heat exchanger where coolant is used to cool oil before it goes to the main bearings and cam shaft. It will also bring oil up to operating temperatures much more quickly on a cold engine.