darrenjlobb's Adaptronic Managed Compound Blown Derv Bus Build

[darrenjlobb]

Another small update, Have started to look into the cambelt / fuel pump etc side of things. Am going to be running a fairly large CP3 style HP pump on this engine, for several reasons really, but overall just felt its the way I want to go. Although a smaller bodied pump would fit most likely on a stock bracket and work, I want to use a large body pump however, which just isnt physically going to fit on the stock bracket / belt arrangement.

So decided best way forward would be to isolate the HP pump from the cambelt entirely, and fabricate my own bracket etc for it, and run off an Aux belt. Therefore simplifying the cambelt to just the crank and cam, which once fitted can be left well alone and not touched (hopefully!)

So as the RHR / Siemens managed versions of these engines actually have this simple cambelt setup, I had hoped to use all the parts off this engine, and got hold of a block for this purpose, however as I have found with most aspects of this build, things that look like they will just bolt up, don't, and overall, this plan was fairly useless / didnt work out.

So the side of the engine starts out looking like this:



After mocking up the proposed idea a few times, it became apparent that I couldnt use the stock tensioner location, as it was to low (down on the block) and pushed the belt to close together to where they would touch (not good) so decided the best way would be to relocate it up on the top, on the cylinder head. So drilled and taped a hole and fitted a stud to the head. Obviously this isn't an "ideal world" method of doing this, If i had realised before I would have done this while head was removed, but with some care / people watching drill angle etc, I was able to get a good square hole, and tap it effectively.






This allowed me to bolt up a tensioner:




Next part of the problem, is with the stock RHW engine mount housing, the belt wants to rub on it, as it was designed for the belt to go up and over to the pump, not down behind, the RHR has a pulley built into the bottom of it, to relieve this problem. However the housing does not fit directly to the RHW block / head combo. So in the end I re drilled one of the holes in the block, and relocated the top right hole on the housing. Which allowed me to put 3 of the four bolts in, leaving just to top left bolt, which is a big dowell also.

I wanted to retain this dowell as adds alot of strength to the setup, but the size of the dowell hole in the engine, was much bigger than the hole in the housing, so reamed out the housing to be a good fit on the RHW dowell, and then found the stock dowell was also to short, so cut the head off it:



Drilled it out:



And then tapped it out to take an m8x1.25 to allow me to bolt it up solid, then fitted it to the head:




Here you can see the complete assay bolted up, looking almost stock:



And then the belt fitted / timed up:




Thanks for reading