Originally Posted by Marshall Muller
My old Perkins
4.236 is running great, but has developed a fuel
leak on top of the injection pump. It is in where the shutoff valve shaft runs through the top of the pump into the pump itself. Can anyone tell me if this is a simple fix of a seal or if I need a new pump? Please tell me it's a simple seal replacement.
Any help appreciated.
Hi Marshall Muller, It is a relatively simple job to do if the pump is on a bench, however if it must be done whilst still in position, be prepared for at least a few cuss words. but firstly check that the top aluminium section is drained, there is a bleed screw near its lower edge. normally this section is not flooded with fuel but over a long period it may fill up. before you start the engine
open this screw and drain the contents. Make sure you have the correct bleed screw, there is another one a little lower on the main part of the pump body. run the engine
for a while and check that the leak has stopped. If it hasent, unless you have access to a good suitable workshop, its best to remove the pump complete and take to a specialised commercial diesel
repairshop. The problem is O ring seals
, but the dismantle and replacement of that top section, which is also part of the governor, requires experience. If you do remove the pump, on the forward edge, near the three fixing nuts, there is an engraved line on both the pump edge and the mating face, which should be in line. If it is not, or not visible, make a new line across both parts
to make sure it goes back exactly right. this is the injection timing line. Ensure the engine is not turned even slightly whilst the pump is off, or you will have diffficulty getting it back. it can only go on one way as the drive shaft is splined with an offset. let me know how you get on.. h the boat