Sammy-Young

Hi all, I am new and really enjoying this forum. I just picked up a 2004 S430. The key fob did not work on the doors. The issue was traced to a defective vacuum pump in the trunk. 2 days after replacing it with a new one, it also died. I had it again replaced but this time I asked the mechanic to trace to the actual fault instead of simply replacing the vacuum unit. after about 15min into his diagnostics, he said all 4 actuators to each door was leaking. I do not believe all 4 actuators can die all at once. Can you the expects please tell me what you think the issue is as the replacement of these vacuum are very expensive. Thank you all for your time and advise.

wallyp

Go here https://www.benzworld.org/forums/w22...tart-here.html and spend some time reading. Use the search function, or Google, to investigate the PSE (Pneumatic Service Equipment) - knowledge will save you a lot of money and frustration.

Sammy-Young

Thank you so much Wally... will do and revert with findings!

gakali

All my door actuators including the trunk one leak. They probably die one by one and if left un-fixed you end up needing all of them. I'm not sure if the repair kits available out there are the way to go for a final solution. I'm wondering if it could be worthwhile to try to coat the cracked actuators with some sort of plastic compatible epoxy. May we worth a try considering the cost of a complete set of actuators...

Sammy-Young

Thank you Gakali, Will try coating the cracked units and hope for the best. I will get back to you with results. Thanks again

wallyp

Some folks added nylon wire ties looped tightly around the plastic pneumatic units to help the epoxy hold them together. Slow-curing, strong epoxy, such as JB Weld, is better than cheap, fast-curing epoxy.

Sammy-Young

Thank you Wally. This is another helpful information that I will try.

mjoecups

Epoxies are mostly brittle so no.

mjoecups

Also, I have just gone through a PSE troubleshooting episode on my 1999 e320. I am suspicious that the "new" PSE your mechanic installed might have been marginal. There is lots on info on testing the actuators using a hand operated vacuum pump.

Keep in mind these do NOT need to be perfect. they only need to hold enough vacuum to make the buttons go up and down. after that the pressuere bleeding out is not a big deal.

wallyp

We used epoxies to glue aircraft structures together, and some cars and trucks are now built with epoxies. Cheap, quick-curing epoxies are not adequate. Good epoxies are stronger than the original plastic.

mjoecups

Of course. I love epoxies and use them for lots of different jobs, including Hextal for glass repairs! My point was that it isn't flexible, so if you trying to glue a flexible part like a boot, it's the wrong choice. Apologies if I misunderstood the application.

gakali

I just repaired my left side actuators and they seem to be working well. They both had a small crack where the rubber hose attaches to the vacuum/pressure motor. The lower housing part which is serviced in the repair kits hardly had any cracks but I reinforced/sealed that area anyway. There's no way they can leak now IMO.

I used Gorilla Glue epoxy and am pleased with the results. Sets in 5 minutes but takes at least 24 hours to fully harden. I used this same stuff to fix a fridge door shelf that was broken clean in half so it passes my test.. One tube will do my whole car no problem.

For anyone removing these units for the first time be aware that it's a more "advanced" procedure than your old Chevy Also be sure to have some 3/16 short metal rivets on hand.

This is what I used:

wallyp

"Apologies if I misunderstood the application."

Okay, that explains the cross-communication. The application in this case is repair of one of the numerous vacuum actuators found on our cars. The common failure is cracking, breaking or separation of a flat cylinder of rigid plastic that contains a rubber diaphragm.

https://www.ebay.com/i/142061772976?chn=ps