Brake vacuum booster...is it neccessary? 1973 280C M110

[Ark of MU]

The vacuum brake booster on the passenger front of my M110 is giving me grief. It seems all other 280Cs, I've seen, don't have this. Why is it there? Can I bypass the pump (see pic) and go directly to the intake manifold? Seems to be plenty of vacuum at the manifold. Also, I updated my Steering box post with some pics...Pg. 2, (4.28.11).

[Benz Dr.]

Not all 280"s have vacuum pumps. I hooked mine directly to the intake manifold and it worked fine.

[kraakevik]

The vacuum pump on DOHC M110 engines merely obstructs justice, siphons power and provides a direct path for oil mist in the crankcase to be sucked into the manifold and burned, sometimes in spectacular quantities--Mercedes dispensed with them circa '75 or so.

There's a stamped-steel cover plate you can buy from Mercedes or pick up in a salvage yard to mask off the hole in the camshaft tower. You'll need shorter screws or closing bolts--any gasket paper or rubber will do--I've used inner tubes.

The plastic piping to/from the intake manifold is re-routed to the booster on the power brake assembly--you keep the big check valve in line between the two. Good luck



Tim Kraakevik
kraakevik@voyager.net
Four 114's, four M110's

[JMURiz]

So on a car like this would you just remove the pump and bypass the pump by running the brake line right into the manifold?

I may look into this, as I think it's #1 ugly and #2 a power sapper.

[JMURiz]

Like this....only I'd remove the pump on the front of the engine...

[kraakevik]

Nathan

Yes--but you need a cover plate on hand, shorter closing screws and an assortment of metric allen sockets of varying length to get the pump off--it may take some time


Tim Kraakevik
kraakevik@voyager.net