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#1

Mechanicals / Re: Vacuum locking system

Last post by Neil4speed - Yesterday at 05:43 PM

If you took that much effort to do an in-depth restoration, I would 100% take the effort to sort the vacuum system. Not to say it is simple, but it is fixable generally speaking.

Also share some pictures!! We want to see your car

#2

Mechanicals / Re: Heater always on

Last post by 79W116 - Yesterday at 12:48 PM

I experienced the same with ACC.  Replaced with UWT electronic controller.  A big mistake.  Rebuild the existing unit.

What is a UWT please?

Unwired Tools

Ah, perfect, thank you.

#3

Mechanicals / Re: Vacuum locking system

Last post by raueda1 - 21 April 2024, 08:07 AM

Invest some time into identifying, and getting rid of leaks.

Replace all lock actuator diaphragms on principle. Same with rubber tubing connectors. Make sure all check valves are in working order. Replace rear and front vacuum reservoir grommets where the hard line enters the reservoir. Replace vacuum valves in heating system, or at least check for leaks. Check the master lock valve, it's a common source of leaks.

Do one thing at a time, then vacuum test the whole system. If it still leaks, move to the next item on the list. Once leak free, the system works perfectly fine.

^^^^THIS.  And to elaborate a little, it's a good practice to use a little silicone grease on the rubber fittings.  It makes tubing easier to install and contributes to an even better seal IMO. The check valves are cheap and readily available.  And pay special attention to the master lock valve.  Mine failed and the brand new replacement turned out to be not good.  !!!???  The supplier sent a replacement and all was fine.  However, the positioning/alignment with the locking lever is critical. Even a tiny bit off and it will appear to leak even if valve is good.  A secondary benefit is that you can clean and lube window mechanism while door is open, though you probably did that during your frame-off. 

And I agree with Daniel FWIW, keep it stock.  Installing electric would end up being a bigger job than just fixing it. And please post some pix of your project!  Everybody here loves that kind of thing.  Cheers,

#4

Mechanicals / Re: Heater always on

Last post by daantjie - 20 April 2024, 08:46 PM

I experienced the same with ACC.  Replaced with UWT electronic controller.  A big mistake.  Rebuild the existing unit.

What is a UWT please?

Unwired Tools

#5

Mechanicals / Re: Heater always on

Last post by 79W116 - 20 April 2024, 08:27 PM

I experienced the same with ACC.  Replaced with UWT electronic controller.  A big mistake.  Rebuild the existing unit.

What is a UWT please?

#6

Mechanicals / Re: Vacuum locking system

Last post by daantjie - 20 April 2024, 03:11 PM

Indeed yes converting the system to electric would be a mistake in my opinion. It is part of what makes a 116 a 116 and once sorted the system actually works very well.

#7

Mechanicals / Re: Vacuum locking system

Last post by ptashek - 20 April 2024, 03:06 PM

Invest some time into identifying, and getting rid of leaks.

Replace all lock actuator diaphragms on principle. Same with rubber tubing connectors. Make sure all check valves are in working order. Replace rear and front vacuum reservoir grommets where the hard line enters the reservoir. Replace vacuum valves in heating system, or at least check for leaks. Check the master lock valve, it's a common source of leaks.

Do one thing at a time, then vacuum test the whole system. If it still leaks, move to the next item on the list. Once leak free, the system works perfectly fine.

#8

Mechanicals / Vacuum locking system

Last post by Chigham - 20 April 2024, 12:32 PM

So I'm new this this forum .  I own a
1979 6.9 450 SEL that I did a frame off
The only thing not working properly on
Vehicle is the vacuum locking system

I've been told that it better to convert to
Electrical system .  Less problems vs the
Vacuum locking system .

Does anyone have any thoughts or expertise
In this matter ?  Much appreciated

[There is no additional charge for starting new topics!]

#9

Mechanicals / Re: Staying On Topic

Last post by Chigham - 20 April 2024, 12:29 PM

Please keep all discussions on topic and respect the discussion instigated by the original poster.

There is no additional charge for starting new topics!

Should you wish to take any discussion off topic, please do so by starting a new topic in the appropriate category. In such a case, you may still quote from the original discussion.

Should the topic starter discover the subject for the original issue is incorrect due to a misdiagnosed issue, please take the time to change the subject to reflect the correct issue.

Staying on topic ensures that discussions are easily found by all existing and new members and ensures that anyone wishing to participate in the discussion can do so without confusion or distraction.

#10

Mechanicals / Re: Some technical questions a...

Last post by Chigham - 20 April 2024, 12:28 PM

I'd check out Kent Burgsma on Mercedessource on YouTube for tips on the vacuum leaks.  My central locking lasts for about 20mins so enough time to lock the car but not enough to reopen her for all the passengers.  Ive done some chasing of the lines for obvious leaks without luck.  The vacuum tank is under the rear parcel shelf.  If you are getting 2 hours, its actually pretty good.  My tensioner also looks bent but otherwise no squeals.  I do have a noisy ac clutch and the system runs quieter with the ac on