[MBZ] W124 Vacuum Leaks
Since I resurrected my W124 from its Covid slumber I noticed it was balking slightly at shutoff and yesterday it seemed very noticeable after the trip home. Got here to the old nuke plant this morning and the old girl wouldn’t shut off without me going out and “mashing the rack”. I realize almost anything may have deteriorated after sitting out pretty much unused all last, awful summer. I had become adept at hunting down leaks in W123s and I reckon these aren’t too different but this is my first vacuum issue for me on one of these and I wondered if there are any pointers, any known offenders, any usual suspects when hunting vacuum leaks on this. Bob R Sent from my iPhone ___ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] W124 Vacuum Leaks
Sounds like the vacuum shut off valve on top of the injection pump has failed. Check the connections to it for soundness. Make a temporary connection that you can stick one end in your mouth, and see if you can suck the lever to the down position. If that test fails, time for a new valve. Replacing that valve with the intake manifold in place can be tedious. The connection for the rack position sensor blocks removal, so you twist the collar lefty loosey about 90 degrees and then pull up on the connector to remove. Max Dillon Charleston SC Jan 7, 2021 8:38:42 AM Bob Rentfro via Mercedes : > Since I resurrected my W124 from its Covid slumber I noticed it was balking > slightly at shutoff and yesterday it seemed very noticeable after the trip > home. Got here to the old nuke plant this morning and the old girl wouldn’t > shut off without me going out and “mashing the rack”. > I realize almost anything may have deteriorated after sitting out pretty much > unused all last, awful summer. I had become adept at hunting down leaks in > W123s and I reckon these aren’t too different but this is my first vacuum > issue for me on one of these and I wondered if there are any pointers, any > known offenders, any usual suspects when hunting vacuum leaks on this. > > Bob R > > Sent from my iPhone > ___ > http://www.okiebenz.com > > To search list archives http://www.okiebenz.com/archive/ > > To Unsubscribe or change delivery options go to: > http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] W124 Vacuum Leaks
First step is to put a mityvac on the shutoff itself. No point chasing other leaks if that isn't working.From there work backwards to the switch. Its a pretty simple system. -Curt On Thursday, January 7, 2021, 8:38:42 AM EST, Bob Rentfro via Mercedes wrote: Since I resurrected my W124 from its Covid slumber I noticed it was balking slightly at shutoff and yesterday it seemed very noticeable after the trip home. Got here to the old nuke plant this morning and the old girl wouldn’t shut off without me going out and “mashing the rack”. I realize almost anything may have deteriorated after sitting out pretty much unused all last, awful summer. I had become adept at hunting down leaks in W123s and I reckon these aren’t too different but this is my first vacuum issue for me on one of these and I wondered if there are any pointers, any known offenders, any usual suspects when hunting vacuum leaks on this. Bob R Sent from my iPhone ___ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] W124 Vacuum Leaks
> I had become adept at hunting down leaks in W123s... Take a W123, and subtract the door lock system from consideration. There you go. -- Jim ___ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] W124 Vacuum Leaks
Jim Cathey via Mercedes writes: >> I had become adept at hunting down leaks in W123s... > > Take a W123, and subtract the door lock system from consideration. > There you go. Works on W116s as well. The weak points are where the plastic lines run from the car to the door, the constant flexing from opening and closing the door eventually cracks them. Also the diaphragms in the door lock servos can fail. I did have a failed shut-off valve, and failed vacuum pump for that matter, when I first got my W116. Rebuilt the pump and replaced the valve, replaced all the rubber wye and cross fittings, and it still loses vacuum after a few hours. I think it's the front passenger door lock but have not been sufficiently motivated to dig into it. Allan ___ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] W124 Vacuum Leaks
> I think it's the front passenger door lock Certainly a prime suspect, but there's also the HVAC system, and the vacuum reservoir itself to look at. -- Jim ___ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] W124 Vacuum Leaks
I think the point was that the 124s (and 201s for that matter) don't have the concern of the door locks because they're on a separate system fed by an electric pump. Thus when troubleshooting shutoff problems you don't have to worry about the doors causing the issue. -Curt On Thursday, January 7, 2021, 1:23:51 PM EST, Allan Streib via Mercedes wrote: Jim Cathey via Mercedes writes: >> I had become adept at hunting down leaks in W123s... > > Take a W123, and subtract the door lock system from consideration. > There you go. Works on W116s as well. The weak points are where the plastic lines run from the car to the door, the constant flexing from opening and closing the door eventually cracks them. Also the diaphragms in the door lock servos can fail. I did have a failed shut-off valve, and failed vacuum pump for that matter, when I first got my W116. Rebuilt the pump and replaced the valve, replaced all the rubber wye and cross fittings, and it still loses vacuum after a few hours. I think it's the front passenger door lock but have not been sufficiently motivated to dig into it. Allan ___ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] W124 Vacuum Leaks
It’s been my experience that the valve on the front (driver’s) door rarely leaks. It’s pretty robust. One often missed item is the bushing that seals the vacuum line to the vacuum reservoir in the front fender. Like windshield washer pump bushings, I keep one of these on hand. -D > On Jan 7, 2021, at 1:49 PM, Jim Cathey via Mercedes > wrote: > >> I think it's the front passenger door lock > > Certainly a prime suspect, but there's also the HVAC system, > and the vacuum reservoir itself to look at. > > -- Jim > > > ___ > http://www.okiebenz.com > > To search list archives http://www.okiebenz.com/archive/ > > To Unsubscribe or change delivery options go to: > http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com > ___ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] W124 Vacuum Leaks
Curt Raymond writes: > I think the point was that the 124s (and 201s for that matter) don't have the > concern of the door locks because they're on a separate system fed by an > electric pump. Thus when troubleshooting shutoff problems you don't have to > worry about the doors causing the issue. Yes on a closer reading I agree. Allan ___ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
