Hi,
In order to ensure the timing is correct on a mechanical fuel injection pump, first rotate the engine to the top dead center (TDC) and engage the TDC timing pin with the camshaft gear. Then remove the timing pin access plug from the injection pump and verify if the slot in the pin will fit over the timing tooth of the pump. Next, carefully replace the pump to correct the timing, adjusting. Next, remove the clips at the brackets on the injection lines closer to the injectors. Loosen all of the injection connections at the injectors. Do not remove the lines. You can remove the water crossover tube if it is in your way, but drain about a 1/2 gallon of coolant before your remove the crossover. Remove the oil fill tube from the timing. There's a round timing gear cover plate on front of engine, remove that cover plate to access timing gear retainer bolt #24 and remove bolt. At this point, note which hole in timing gear that dowel pin #23 is located in, mark that hole position with paint stick or something similar.Remove all fuel line connections. Correct timing of the Lucas CAV DPA pump can be. Verified by removing the. The timing window. Cover on the injection pump. NOTE: Special equipment in an authorized shop is. Required to precisely time the Lucas CAV DPA. For troubleshooting and in an. Emergency, visual alignment of the timing mark is. Close enough for the engine to run.
I know the manuals say you need specialist equipment to create a hydraulic lock to fix the point of injection to time these DPA pumps properly, but I've never seen it done.
These pumps are driven by a quill shaft with a master spline so its difficult to get it wrong.
Chevy Timing Marks 4.3
The master spline always lines up with the delivery valve which is receiving the injection and there is a scribe mark on the seal housing indicating the point of injection for No. 1 cyl. These then coincide with the master spline location.
Cav Dpa Timing Marks Off Skin
Looking from the drive end of the pump you'll find the mark at 10 to the hour on 4 cyl. engines and 27 past for 6 cyl. engines.
No.1 Point of injection marks.
If the pump has been fitted to the engine before all that is needed is to line up the marks on the pump flange and gear housing and lock up the three 1/2 AF - 13mm. nuts.
Lucas Cav Dpa Manual
One mm. of rotation of the pump body at these marks represents about one degree at the crankshaft.
External timing marks.
On a new engine the pumps are individualy fitted before the timing marks are scribed so they are a matched pair.
If you have to fit a strange pump, and the engine doesn't perform, it is possible to reset these timing marks visualy.
To do this you will need to set the engine up at point of injection No.1, and remove the inspection plate from the side of the pump, (two 5/16 AF set screws). You will then be able to see the pump rotor which will have lettered scribe marks on it and a large circlip with one square end.
Cav Dpa Timing Marks Office
Slacken the pump boddy and turn it till the square end of the circlip lines up with the scribe mark on the rotor. The mark is lettered A on 4 cyl engines and D on 6 cyl.Lock up the pump in that position and make your own new timing mark on the pump flange, a sharp chisel does the job nicely.
Internal pump timing marks