Rod Interference with Oil Pump

[CBRacerX]

OK, so I bought some R&R aftermarket rods for my 3.6->3.8 964 project. Doing a fit check tonight, I found that the rods interfere with the oil pump on the 3, 5 and 6 big ends. I've certainly heard of clearancing the pump before, but have not done so myself. Any tips, constructive thoughts, procedures and/or pictures?

Thanks! Would like to nail this down and keep the rebuild going!

[MBEngineering]

HI is the rods in contact with the oil pump when the cylinder and piston is fitted?? or without, Just be careful removing anything of the oil pump as the case is not that thick!!!

regards mike

[CBRacerX]

Originally posted by MBEngineering
HI is the rods in contact with the oil pump when the cylinder and piston is fitted?? or without, Just be careful removing anything of the oil pump as the case is not that thick!!!

regards mike

Yes, the rods touch the oil pump case. In using Carillos for example, you must remove .5 mm from the oil pump case to fit the rods.

[eapcpa]

Chris I think what Mike was saying is that if you are test fitting the rods without the cylinders and pistons (without rings) you may find clearance issues. The pistons and cylinders center everything properly.

[CBRacerX]

Originally posted by eapcpa
Chris I think what Mike was saying is that if you are test fitting the rods without the cylinders and pistons (without rings) you may find clearance issues. The pistons and cylinders center everything properly.

I'm afraid I already thought of that before the post . This occurs with the P&C installed.

[MBEngineering]

HI put some putty, plasticine or dum-dum in there on top of the pump, then refit and turn over, both ways to check how/where you will need to remove material and the depth to go to , off the rods if poss, which pump are you using as the mag Carrera 2/4 pump is very thin to set of with????

regards mike

[CBRacerX]

[MBEngineering]

HI I would mod the rods for clearance and re balance for the amount to be taken off to clear, and you need to do something with your oil pump lock tabs if you are using them as thay are not locking the nut, either turn them 90 deg anti-clock wise, so the bottom tab is up against the pump case and cannot turn or use "schnorr" washers.

regards mike