Pagoda SL Group

W113 Pagoda SL Group => Drive train, fuel, suspension, steering & brakes => Topic started by: Neil Thompson on August 21, 2016, 20:11:37

Title: Revs increase when brake pedal applied...
Post by: Neil Thompson on August 21, 2016, 20:11:37: ... then stalls when gear selected.

230SL Auto with PAS, restored car thats been stood with poor fuel, see my other post re elec fuel pump.

I've cleaned all the fuel lines, set the points, adjusted the ignition timing and also adjusted the linkages/venturi as per the basic linkage tour on the forum. The car runs well and idles ok at around 800rpm. If I press the brake pedal the revs rise to around 1,300rpm, if i then put it into gear it stalls. There are some things in the tech manual I haven't tried to test yet such as the WRD and the CSV as I've ran out of daylight but I thought I would just throw my problem out to the experts hoping for a quick fix. Could the mixture just be too rich on tickover or could the servo be dodgy?

as always, any help welcomed

Regards Neil
Title: Re: Revs increase when brake pedal applied...
Post by: stickandrudderman on August 21, 2016, 20:33:05: The search function is feeling hurt that you are ignoring it!
Title: Re: Revs increase when brake pedal applied...
Post by: Neil Thompson on August 21, 2016, 21:32:31: I've searched Colin, but sometimes it's good to talk!

Neil
Title: Re: Revs increase when brake pedal applied...
Post by: dpreston Virginia on August 21, 2016, 21:39:45: Sounds to me like a bad brake booster.,
Title: Re: Revs increase when brake pedal applied...
Post by: ejboyd5 on August 21, 2016, 22:20:59: Plug the vacuum connection to the brake booster to see if the problem goes away.
Title: Re: Revs increase when brake pedal applied...
Post by: rgafitanu@gmail.com on August 22, 2016, 17:22:21: I had the same thing,it is a leak in the brake booster. Take it to NAPA, they will rebuild it for about $100. Anything else on the internet and ebay is very expensive.

Radu
Title: Re: Revs increase when brake pedal applied...
Post by: Rolf-Dieter ✝︎ on August 22, 2016, 22:04:00: Colin is right ... Look at the search results

Here ----> http://www.sl113.org/forums/index.php?action=search2

Let us know how you made out, not just for us also for others that will use the search in future years.

Dieter
Title: Re: Revs increase when brake pedal applied...
Post by: Cees Klumper on August 22, 2016, 23:23:37: Quote from: Radu G on August 22, 2016, 17:22:21
I had the same thing,it is a leak in the brake booster. Take it to NAPA, they will rebuild it for about $100. Anything else on the internet and ebay is very expensive.
Radu

Good advice, except TS is located in UK where NAPA may not exist ...
Title: Re: Revs increase when brake pedal applied...
Post by: Pinder on August 23, 2016, 12:58:41: I had the same issue. Was brake booster. I got mine from Rockauto. If Napa rebuilds original that would be a good option. Rockauto was pretty cheap at around 100 with core refund.
Title: Re: Revs increase when brake pedal applied...
Post by: Pawel66 on September 17, 2016, 07:35:08: Just a voice here and if you find it contrary to forum's wisdom, please ignore it.

I had the same thing - revs changed as the brake pedal was pressed. Before a major booster overhaul I replaced a simple oring between the booster and brake master cylinder. The symptoms are gone. Revs do not change.

I was reading Haynes and I spotted a sentence that this oring needs to be "vacuum tight" and needs to be renewed while working on booster. So I did that.

Pawel