450SL Fuel Delivery Problems

[nickandjudy]

We have a '74 450SL and have fuel delivery problems.

The fuel is delivered through the first regulator (called 'Regulator' or 'Damper' in manuals).

The second regulator or distributor (1 inlet, 2 oulets, 1 to each bank) does not let any fuel through. The manual says about 45psi. I tried 50 psi of compressed air, but it did not flow through to the outlet ports, even after backing out the adjusting screw.

Is air a good way to test?

For testing, can I eliminate the distributor with a 3-way fitting for testing only?

Thanks for help in advance.

[GeorgeMurphy]

We have a '74 450SL and have fuel delivery problems.

The fuel is delivered through the first regulator (called 'Regulator' or 'Damper' in manuals).

The second regulator or distributor (1 inlet, 2 oulets, 1 to each bank) does not let any fuel through. The manual says about 45psi. I tried 50 psi of compressed air, but it did not flow through to the outlet ports, even after backing out the adjusting screw.

Is air a good way to test?

For testing, can I eliminate the distributor with a 3-way fitting for testing only?

Thanks for help in advance.

First get the shop manual on CD for that car and engine before you destroy an expensive part with excessive air pressure . . .

Call 800- 367-6372 to order from MBUSA . .

Then get a EFI test rig to measure properly the DELIVERY pressure and the CONTROL pressure to properly diagnose . . .