Some adjustments have to be done,
and still a few details to attend to.

 

Timing the acceleration of the Caprice with Benz power yeilded a somewhat disppointing result. 0-100 kmh (0-62 mph) took us a respectable 35 seconds. Obviously the turbo charger worked as a very effective exhaust brake most of the time. It seemed it was time to adjust the diesel pump to inject more fuel.

To adjust the pump, the rear cover has to be removed. As the pump is close to the oil filter housing, some of the work was done via a mirror. This is a rear view of the diesel pump. A was screwed out two and a half turns to increase fuel. B (coarse idle) was turned out by the same amount to lower the idle These two adjustments took the 0-100 kmh time down to 20 seconds. A fifteen second improvement, but it's still slow.

A second try at adjusting the pump was a disappointment, as the fuel adjustment bottomed out after turning it out a quarter of a turn more. Same thing with the coarse idle adjustment. No improvement to the power output of the engine. As the idle was too high now, the fine idle adjustment screw (not seen in the pic above) was used to lower the idle a bit. The two round thingies here are the high idle solenoid (left) and the anti-yank solenoid, which cuts fuel and is taken out of use by removing the actuating pin. Both solenoids were ground to avoid interfering with the severely ajusted fuel and idle screws. Both these solenoids mount to the rear of the fuel pump.

After driving around in a lazy diesel powered wagon a few months it was decided that a better injection pump had to be mounted to the engine. Here the new pump from Herlevi of tractor pulling fame has just arrived. The tiny 5,5 millimeter pump elements have been substituted for 8 mm ones. This pump should be good for some 600 horse power, but the engine won't take more than 200+, so it's adjusted to low settings. (December 2014)

A tool for adjusting the injection timing was made out of a drill bit that fits the bore of the inspection hole on the pump. A slot was cut with an angle grinder exactly(!) in the middle to ensure that the pump was adjusted to 18 degrees before top dead center. The pump was built so that it now uses true adjustment, instead of the odd standard Mercedes procedure of adjusting the timing @ 15 degrees after TDC.

After fitting the modified pump the exhaust emits a bit of black smoke. What is not evident in this video clip is the nice accelleration, the 0-100 km/h (0-62 mph) times have about halved. It's a lot more fun to drive the hearse now that it's noticably faster than it was with the V-8

THE BEGINNING   THE MECHANICALS   THE DETAILS

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