Garage => Mechanicals => Topic started by: Janse on 31 August 2019, 09:02 AM

Title: new radiator
Post by: Janse on 31 August 2019, 09:02 AM
My radiator starts to leak when i start driving. When stationary no water comes out, I cant see any wet spots, the water gathers at the bottom of the radiator. I have no experience with radiators, except I once saw McGyver fix one with eggs...
Title: Re: Radiator leak when driving
Post by: revilla on 31 August 2019, 02:01 PM
I guess I missed that episode LOL
I wish it was that simple...

In our cars, the typical radiator leaking is around the welding line between top cover and the coil. It leaks mostly when the car is running and that’s probably why you aren’t seeing a spot on the ground. Refrigerant evaporates on contact with the coil but it should leave white marks.  Both of mine developed that failure mode. A small radiator shop around here was able to solve the problem (rewelding the top cover) but the big garages wanted to change the whole unit.  It’s been a few years after they were repaired and so far they’r holding just fine (even at hot 38C days in traffic).

Good luck

Title: Re: Radiator leak when driving
Post by: Janse on 31 August 2019, 03:00 PM
I see i have explained myself poorly. I have a huge puddle underneath the car when I stop, and it continues to drip for a couple of minures after I turn the engine off. And water is seen at the outside bottom of the radiator. After a few minutes the dripping stops. I ment before to say that the rest of the radiator looks dry. I have been googling and maybe a faulty radiator cap can be the issue? I have been changing water frequently lately as the engine has been sitting for many years and I have just got it running. So I want to flush out as much goop as possible before I tuck it away for winter.
Title: Re: Radiator leak when driving
Post by: revilla on 31 August 2019, 11:21 PM
I see now. One of the advantages of using refrigerant is that it leaves those white traces to help with identifying leaking points.
The cap can be an issue, true, but before that check the connection between hoses (2 in/out) and radiator as they tend to drip. I see as “good news” that you see the water accumulating just under the radiator and not deeper behind which could mean a pump leaking (worse news!).  Also, be aware that if you fill it up completely when cold it’s normal to have a puddle because the excess has to leave the circuit through the little hose next to the cap once it expands at hot temp. That’s precisely the job of the spring-loaded cap and the little hose next to it. Just in that area, check also the nipple that comes out of the neck of the filler opening, they get loose and they leak too. This is less critical as it’s refrigerant at atm pressure not part of the cooling system but simply letting the excess drain out.
Hope it helps.
Title: Re: Radiator leak when driving
Post by: Janse on 01 September 2019, 02:53 PM
A little update. The car has been sitting for a day, and I just popped out to see how it was doing. I opened the radiator cap, and water started comming out somewhere at the bottom right, and it gathers on the little tray at the bottom of the radiator and spills over at the drain plug.
Title: Re: Radiator leak when driving
Post by: rumb on 01 September 2019, 05:26 PM

When you say bottom right, you mean that if you are standing in front of the car looking at the engine it would then be on your left?

Does the overflow hose go from just beneath the radiator cap to that area?

After sitting a day there should not be any pressure left in the cooling system.

Your car is a 280SE? does it have an expansion tank for the radiator?
Title: Re: Radiator leak when driving
Post by: Janse on 01 September 2019, 09:49 PM
Left when standing in the front. The water is not comming from the overflow hose, the hose is much longer and goes below the radiator. There was a PSSS! Sound when I opened the radiator cap. Its a 280S, not sure what an expansion tank is...
Title: Re: Radiator leak when driving
Post by: Diesel 617 on 02 September 2019, 08:30 AM
Likely you car does not have any expansion tank (look up an image of a 350,450 or 300SD w116 engine bay you will see a yellow/white plastic tank above the right side fender) My Euro import 280SE has no such tank.

You will need to crawl around the radiator to find the source of the leak, it could be a hose that has worn out expanding under the high heat causing the leak, or it could be the radiator expanding under the heat opening up a hole in the radiator allowing it to leak. Figure out if it is in fact coming from the radiator. If it is you have two options, leak fix will likely not fix this by the sound of it, it sounds too large of a leak.
A. Find a radiator shop to re-core and reseal it (they will clean it and return it like new)
B. Find a used radiator from another 280 and have it cleaned prior to install to verify it is leak free.
Title: Re: Radiator leak when driving
Post by: Janse on 02 September 2019, 02:49 PM
I have found the leak. After cleaning the radiator with compressed air i now see where the water is coming from. Its hard to explain, but just above where the lower hose connects to the radiator, at the bottom of where the water gets cooled there is a tiny hole. I suppose there has been a hole there for some time, but when I now have started using the car the rust has come off and revealed the hole. Can I use leak fix with this damage? I dont know about this product.
Title: Re: Radiator leak when driving
Post by: revilla on 03 September 2019, 10:12 AM
The liquids/powder products have only worked temporarily for me in the past on other cars.  Plus, we don’t know of possible negative effects of such products on the pump/gaskets etc.
For a permanent/safe fix, the advice from Diesel is the best approach.  Find yourself an old-fashion radiator garage where they can repair the leak and take advantage to clean the core.  You can remove the radiator yourself (not complicated, easier than what it looks like) which will save you $ at the end. When done I suggest you flush the circuit too and put cooling refrigerant instead of water. I’d remove every drop of water to prevent corrosion.
It’s a good thing to do it now before the winter so water don’t seat there for too long.  This is probably (???) why your temp sensor went bad in first place.
Good luck.
Title: Re: Radiator leak when driving
Post by: Janse on 03 September 2019, 02:11 PM
The radiator is out. I will get a new one. I have only been using water to flush out the system, the plan was to put coolant in before winter, but it is allready getting pretty chilly here so i need to hurry. The car has been sitting for 20 years so I am pretty surprised that there is not more wrong with it :)  thanks for tje input.
Title: New radiator
Post by: Janse on 04 September 2019, 11:35 PM
Are there any differences between the radiator on a manual and automatic transmission 280S? I have come over a new one, but it is for an automatic. Will it fit?
Title: Re: new radiator
Post by: floyd111 on 05 September 2019, 07:19 PM
I see these for 280SE AND 280S at . Same list. Not helpful.

A 1165011001
A 1165011901
A 1165011801
A 1165011501
A 1165011701
A 1165012601

There must be better data, but this is what I found..-and it don't make sense to me.

xx001 and xx002 are the same, both for automatic
xx801 and xx 901 are the same and both for  automatic
XX 401 and xx501.. can't find data
xx 601 manual
xx701 automatic for 6.9
xx801 and xx901 automatic

German-SPOB lists the xx001 as for both AC and non-AC cars, both manual and automatic. also lists that data.
With that, I join the club of those wanting to know what's what.

Title: Re: new radiator
Post by: rumb on 06 September 2019, 07:01 AM

Only one listed for 280S.  no mention of trans type.

Does the one in your car have the 2 small hoses at the bottom that are used for trans cooler?  I would think you do not based on what I see in EPC.

For the 280SE it lists A1165011001 or A1165011901  with auto trans, and A1165011001 with std trans.

If you can not find one for a std trans I suppose you could put the auto trans one in and just leave the bottom pipe alone.

Here is the correct one
Title: Re: new radiator
Post by: Diesel 617 on 06 September 2019, 10:07 AM
Just to add to the confusion on my 280SE Euro import Non-ACC the radiator is 
1165012101 with smaller oil cooler and trans cooler at the bottom, no expansion tank.

for the 300SD it is 1165012401 with expansion tank and larger oil cooler than 280 (possibly the same for the 6.9)

The above radiators all have the same position of the necks, tans cooler and oil coolers, but the 2401 radiators have expansion tanks where as my 280SE 2101 doesn't have an expansion tank.

Also I read or saw that all NA imports except the 300SD did not have oil coolers.
Title: Re: new radiator
Post by: floyd111 on 06 September 2019, 05:34 PM
First, there must be a proper oversight of this somewhere, wouldn't you think? Or is it a VIN-based search only?
Maybe the secret lies with knowing whether you have an oil cooler and an expansion tank? But then what? I remember a radiator discussion here years ago, Sure there was better data available then. Aaron should know these things! :)
Title: Re: new radiator
Post by: Janse on 09 September 2019, 01:02 PM
The part number for my radiator is
116 50120 01

i have a manual 280s

And the one I might get my hands on is 116 501 18 01

Title: Re: new radiator
Post by: rumb on 09 September 2019, 02:53 PM
116 501 18 01

used on:
350se, 350sel, 450se, 450sel

looks like it has connections for overflow tank.

Title: Re: new radiator
Post by: Janse on 10 September 2019, 09:03 AM
It does not fit.  :'( no radiatorcap.