6.3

If anybody is ever scouring the Internet trying to find a modern fuel pump for your Mercedes Bosch MFI system, this model is a perfect replacement. Pump ratings are just advertising. The curve charts are the real deal. This Holley hits 20PSI at 4.5 amps and has plenty of gph flow at that pressure. I didn't need to change the fuse or wiring, and I didn't need to add a pressure regulator. It self primes. You'll need 90 degree hose barbs if you want to mount it on the original M6 studs under the body. I'm done with the short style Bosch fuel pump. I concede my originality prize at the concours. I'll place my free Holley sticker across the windshield, maybe.

Holley Electric In-Line Fuel Pump

HLY-12-920

Fuel Pump, Electric, In-Line, External, 80 gph, 60 psi, 12V

You can try it if you can get a jack under the front in a safe place. It will probably go down again, but while it is up, you may wish to chock it up with either the original front suspension chocks or some small pieces of lumber between the upper and lower control arms.

quote:

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Originally posted by mpmorris

Looking back at your pictures --that rear air valve is the crustiest air valve I've ever seen and I notice one mounting bolt is backed out and appears the mounting bracket has been welded? --my thought is the rear air valve is stuck internally or it is not positioned correctly. for testing purposes, I would loosen the u-clamp on the sway bar, swing the u-clamp down a bit until the car is at normal ride height-- !! Do Not Do This Without Sufficient Supports Under Car!! -then put the ride height controller in full height position to see if the rear now rises to full height. Also --I notice the front is low in all of your pictures --this might be caused by stiff front suspension joints (lack of a thorough grease job) --as a temporary measure --you can raise the air delivery pressure by adjusting the the fill pressure on the main air valve horizontal screw by loosening the lock nut and turning the screw head clockwise -say three full turns --with this extra pressure, you should see the front rise --(please note exactly how much you turn that screw so you can re-set to original setting.
mpm

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Ya there's a lot of rust proofing on the valve. I too believe it is stuck open, or the seal inside is bad.

Could I lift up the front of the car with the jack while the suspension is filling with air and then take away the jack? Should it stay up?? Could that work better than adjusting the pressure??

1970 300SEL 6.3

I have a NOS rear valve I can sell you if interested. PM me if you like.

Daniel
1977 450 SEL 6.9
Vancouver, BC

Looking back at your pictures --that rear air valve is the crustiest air valve I've ever seen and I notice one mounting bolt is backed out and appears the mounting bracket has been welded? --my thought is the rear air valve is stuck internally or it is not positioned correctly. for testing purposes, I would loosen the u-clamp on the sway bar, swing the u-clamp down a bit until the car is at normal ride height-- !! Do Not Do This Without Sufficient Supports Under Car!! -then put the ride height controller in full height position to see if the rear now rises to full height. Also --I notice the front is low in all of your pictures --this might be caused by stiff front suspension joints (lack of a thorough grease job) --as a temporary measure --you can raise the air delivery pressure by adjusting the the fill pressure on the main air valve horizontal screw by loosening the lock nut and turning the screw head clockwise -say three full turns --with this extra pressure, you should see the front rise --(please note exactly how much you turn that screw so you can re-set to original setting.
mpm

My lines run down towards the engine bay. Is there a diagram of where the lines should go and how I figure out if they're switched??





1970 300SEL 6.3

Thx I'll take a look to see if it was switch before hand. I haven't touched the lines though.

1970 300SEL 6.3

yes the valve under the hood.





I think you could have switched the CROSSOVER connections to the copper-coloured connections …

Theorethicly is could be an internal leaking axlevalve BUT praticly I don't believe so ...

That would be the valve under the hood??

Could a leak inside of the rear valve cause it to overfill??

1970 300SEL 6.3

could also be wrongly connected lines at the main-air-valve ...

I can't see anything wrong with the way the rear valve is set up to explain the excessive rear ride height.

Personally, I do not use braided brake lines --maybe for track use to prevent excess expansion of the hose under heavy load but i think they would restrict the dissipation of temperature. I prefer the stock DOT rubber hoses (ATE) simply because when they look old, they are old and need to be replaced --a stainless hose could look new but ready to fail

mpm

Started it back up and the rear went back up above normal again. Much less resistance moving backwards than trying to go forwards.

This is the best shot I could get of the rear valve.



1970 300SEL 6.3

Regarding brake lines - - - These folks are here in the West Palm Beach area and I can highly endorse them. They have made custom products for me for more than 15 years. In fact, they have made DOT brake lines for me in 10 minutes. They fabricated all the custom lines and provided all special AN fittings for the modified fuel injection on my E55K.

Steve

http://makohose.com/?page_id=289target=

Palm Beach Gardens, FL
Niederheimbach, Germany
W109 6.3(6.5)
E55K AMG
CLK63 AMG Gone
Ferrari 400GTC4 Gone
ML400CDI BiTurbo
ML350 CDI BlueTEC
9146GT Gone

I think I have been in Southern California too long as I like that Lowrider look. Maybe a couple of inches up but no more....

it seems that the suspension-airlines are connected wrong …

therear was in the high position and the front seems to be in normal driving position ..

How was the airsuspension button set ?? in high position or driving position …

Back on the ground after two days.... I guess I've got a leak...




1970 300SEL 6.3

quote:

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Originally posted by AgSilver

You might consider braided-stainless steel lines if you plan to replace the existing lines.

Check the rear level control valve.

DANGER WILL ROBINSON!!! As Art said, absolutely make sure you have floor jacks supporting the rear of the auto before going under it.

Steve

Palm Beach Gardens, FL
Niederheimbach, Germany
W109 6.3(6.5)
E55K AMG
CLK63 AMG Gone
Ferrari 400GTC4 Gone
ML400CDI BiTurbo
ML350 CDI BlueTEC
9146GT Gone

---

Anyone have a good source for braided brake lines?? North America.

1970 300SEL 6.3

You might consider braided-stainless steel lines if you plan to replace the existing lines.

Check the rear level control valve.

DANGER WILL ROBINSON!!! As Art said, absolutely make sure you have floor jacks supporting the rear of the auto before going under it.

Steve

Palm Beach Gardens, FL
Niederheimbach, Germany
W109 6.3(6.5)
E55K AMG
CLK63 AMG Gone
Ferrari 400GTC4 Gone
ML400CDI BiTurbo
ML350 CDI BlueTEC
9146GT Gone