w123 280e M110 hot starting problem and rough idle

[tiger280e]

Dear friends,,,so far I replaced Fuel pump, accumulator,fuel pump, fuel pressure regulator, distributor cap, and 300e coil, rebuild warm up regulator, rebuild fuel distributor,,,,but the problem still there,,,,I need to turn the 2-3 times after park about 30 minute,,,,when it's on, rpm very low,,engine shaking,,,after 10 second they jump to 700 rpm,,and then poor running ,,it's just like the rpm won't go up above 2500 rpm,,,and it's just like running with 4 spark plug,,,,the garage try to adjust CO but engine still shaking,,,please help,,,i'm hopeless,,,,,what cause of that symptons,,,,,and what i'm missing.......thanks before...

[daddi]

Adjust the valves and test the compression.

[tiger280e]

..so..I already adjust the valve,,,and the compression is good,there's no oil leak anymore on the spark plug hole ,,engine much calm right now,,,,include change spark plug and the wire,,,,but,,,the problem still there,,,,,any suggestion ?.....

[Frank Reiner]

With all respect, I think there is a bit of difficulty in sorting out the inspections and repairs that you have made so far.

When daddi said to adjust the valves, he spoke in the plural, and was referring to the engine valves. Your reply was in the singular: valve. What valve did you adjust? Did you measure the cranking compression pressure in all the cylinders? What were those pressures?

The hot start problem is typically caused by a loss of retained fuel pressure, and the subsequent percolation of fuel in the lines. When that situation occurs, a number of cycles of the fuel pump are required to build pressure again and clear the fuel vapor from the system. Fault areas include the injector nozzle check valves, and the check valve in the fuel distributor pressure regulator (known as a "push valve").

The failure of the engine to run well once started is a separate problem.
It may be the result of low compression, very retarded valve and ignition timing, and low system fuel pressure due to clogged filters and screens, or a worn out fuel pump (which you seem to have replaced).

[tiger280e]

well,,,i mean,,,i did the engine overhauling.....and today i just replaced the fuel distributor,,,and the garage want to see the result,,,let see if there's any progress....

[tiger280e]

fuel distributor pressure regulator or push valve ?....can you post a pict of that part...?? thanks Frank

[Frank Reiner]

Tiger:

PM me with a email address, so that I can send you some manual pages.
If I attempt to post them here, the files are too small to reproduce legibly.