Author Topic: Heater flap/heater control valve  (Read 8046 times)

catjim813

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Heater flap/heater control valve
« on: November 03, 2013, 23:28:54 »
All I have a 69 280 SL that while cleaning the drain plugs I noticed that the driver side heater flap is broken at the wire cable and plastic pc and the heater control valve was also disconnected from the flap and could not be moved by hand at all.  My question is where do I find this flap and how do I free up the heater control valve for it can function and don't break the new flap?  Thanks for all the previous help from many of you.

Garry

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Re: Heater flap/heater control valve
« Reply #1 on: November 03, 2013, 23:31:51 »
On the firewall Left side there is a largish rubber grommet  that covers an inspection opening giving access to the heater valve.  Suggest you open it and check if the valve is stuck, usually the cause for the broken cable. Use a WD440 type penetrant on it to see if it frees up as a starter.

Garry
Garry Marks
Melbourne/ Kyneton, Brisbane. Australia
1969 MB 280SL 5 speed RHD SOLD.
1965 MB 230SL Auto RHD Lt Blue 334G, Top 350H, Tourist Delivery.
1972 MB 280CE Auto RHD 906G
2005 MB A200
2006 MB B200
2019 Izuzu DMax 4x4 Slide-on camper.
2022 Volvo XC40 Electric
2024 Volvo EX30 Electric

ja17

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Re: Heater flap/heater control valve
« Reply #2 on: November 04, 2013, 03:42:42 »
Yes the heater valve should be freed up first. I remove the heater hose going into the firewall to the water valve.  You can then spray the penetrant directly into the valve itself. Warming the valve with a heat gun also helps before attempting to move it. If your plastic heater flap is broken, remove the little intake air hood, in front of the windshield, you then can remove the flap and repair or replace it. If the heater water valve is badly stuck, you will have to remove the inner cylinder and clean the bore and the cylinder itself (steel wool works good). Do not drop any parts when working on the water valve, also do not push too far  downward on the cylinder. It can fall through into the heater core.

Let us know if you need to remove the cylinder in the heater water valve. Additional information will follow if needed.
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1982 300TD Wagon turbo 4spd.
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback

fblanchard

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Re: Heater flap/heater control valve
« Reply #3 on: November 05, 2013, 06:12:24 »
I had the same driver's side broken flap because of the heater valve stuck.
I discovered it after dismanteling all the dash commands and the heater blower.
I used epoxy resin as a glue and it worked well considering it is not a visible part.
I don't know if the part is available.
Good luck as it is a very deep work and those who went there remember it...
Hope this helps

Fred from Noumea
1969 MB 280 SL red
1971(?) MB 280 SL bordeaux waiting for restauration
1961 MB190 b ponton bordeaux
1961 Vespa VBB1T café crème
2019 Triumph Bonneville black edition
2017 MB GLC diamond white

georgem

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Re: Heater flap/heater control valve
« Reply #4 on: November 06, 2013, 04:15:58 »
Hi Fred,

Good to hear that you are still with us in sunny Noumea. Like you I had a similar problem with the heater flat lever and I also reattached it with epoxy - works perfectly and is probably stronger than the original.

BTW, did you buy that other rescue car you were looking at earlier this  year?

cheers
George McDonald
Brisbane
230 Sl
1973 VW Kombi Single Cab Ute
2022 Volvo XC 40 Pure (100% electric)

catjim813

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Re: Heater flap/heater control valve
« Reply #5 on: November 07, 2013, 02:50:35 »
Thanks to Fred, Garry, and Joe for your replies.  Just when I thought I was in the clear in breaking loose the control valve the worst night mare happen a LEAK developed in the heater core.  OH CRAP   is it the mercury metro grade or what!!!!!!    Now I must go where few have been wish me luck it appears it will be a long hard winter....

Garry

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Re: Heater flap/heater control valve
« Reply #6 on: November 07, 2013, 06:43:32 »
That is the worst nightmare and abig job.  Better to find it rather than a wet floor is one way to look at it. You will get the heater slides working by the time you are finished.

When doing the engine bay in mine the heater tube through the firewall got knocked off.

Unfortunately for you its back to basics and stripping the dash board I suspect.

Garry
« Last Edit: November 07, 2013, 09:47:04 by Garry »
Garry Marks
Melbourne/ Kyneton, Brisbane. Australia
1969 MB 280SL 5 speed RHD SOLD.
1965 MB 230SL Auto RHD Lt Blue 334G, Top 350H, Tourist Delivery.
1972 MB 280CE Auto RHD 906G
2005 MB A200
2006 MB B200
2019 Izuzu DMax 4x4 Slide-on camper.
2022 Volvo XC40 Electric
2024 Volvo EX30 Electric

georgem

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Re: Heater flap/heater control valve
« Reply #7 on: November 07, 2013, 06:50:45 »
Gary,

The other option is having another elbow inserted into each arm - this might reduce the time for getting the core out
George McDonald
Brisbane
230 Sl
1973 VW Kombi Single Cab Ute
2022 Volvo XC 40 Pure (100% electric)

catjim813

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Re: Heater flap/heater control valve
« Reply #8 on: November 10, 2013, 21:18:55 »
Got the core out!!!!!!!    Now are there any new ones out there or do I have to have the old one repaired?????   Also can I find a new control Valve where all the trouble started....   Thanks for the info in the Tech guide and the replies to guide me through it.

Garry

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Re: Heater flap/heater control valve
« Reply #9 on: November 10, 2013, 21:38:28 »
I think you will find it is a whole lot cheaper to take it to a radiator repair shop and have it done and having a go at repairing the control valve will save you lots of money.
Garry Marks
Melbourne/ Kyneton, Brisbane. Australia
1969 MB 280SL 5 speed RHD SOLD.
1965 MB 230SL Auto RHD Lt Blue 334G, Top 350H, Tourist Delivery.
1972 MB 280CE Auto RHD 906G
2005 MB A200
2006 MB B200
2019 Izuzu DMax 4x4 Slide-on camper.
2022 Volvo XC40 Electric
2024 Volvo EX30 Electric

catjim813

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Re: Heater flap/heater control valve
« Reply #10 on: November 10, 2013, 22:23:02 »
Thx Garry will keep you posted. 

fblanchard

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Re: Heater flap/heater control valve
« Reply #11 on: November 12, 2013, 04:27:14 »
Hi Fred,

Good to hear that you are still with us in sunny Noumea. Like you I had a similar problem with the heater flat lever and I also reattached it with epoxy - works perfectly and is probably stronger than the original.

BTW, did you buy that other rescue car you were looking at earlier this  year?

cheers

Hi Georges nice to read you too.

Amazing to see once more that what happens to our treasures happened also to many others and that they succeded in fixing the problem. Helps to feel less alone...

To answer about the "Bordeaux dying pagoda" still impossible to get in touch with the owner. I don't desperate.

Kind regards

Fred from Noumea
1969 MB 280 SL red
1971(?) MB 280 SL bordeaux waiting for restauration
1961 MB190 b ponton bordeaux
1961 Vespa VBB1T café crème
2019 Triumph Bonneville black edition
2017 MB GLC diamond white

dante53

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Re: Heater flap/heater control valve
« Reply #12 on: November 14, 2013, 13:33:17 »
I will soon need to do  the same repair as my left flap is broken. Meanwhile I manually closed the heather valve. Should I drain the cooling system before attempting to remove the heather valve to service it?

dante53

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Re: Heater flap/heater control valve
« Reply #13 on: November 16, 2013, 13:20:31 »
Would anyone reply?

ja17

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Re: Heater flap/heater control valve
« Reply #14 on: November 16, 2013, 14:20:40 »
Hello Dante,

Just loosen the radiator cap. The heater valve is very high up in the cooling system and only a slight bit of coolant will be lost. If you want you can  remove a little coolant from the system before you begin.
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1982 300TD Wagon turbo 4spd.
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback

dante53

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Re: Heater flap/heater control valve
« Reply #15 on: November 16, 2013, 15:38:53 »
Thank you very much Joe. That will be the first of my next winter jobs on my Pagoda!