8v71 engine configuration questions

[bevans6]

I'm installing an 8V71T industrial engine in my MC-5, modifying it using the bus-specific parts from the current 8V71N.  I'm at the point where I have a few questions for the engine gurus.

Fuel plumbing - the bus engine is from the filter head two lines to the input port on each cylinder head, the return from the left side head is plumbed to the return port on the right side head and the return to the tank is from the rear of the right side head.  On the industrial engine, the plumbing is into the left side head, return from it is input to the right side head, and return is from the front of the right side head.  I plan to convert to be the same as the bus engine.  Any reason not to that anyone can forsee?

Fuel pumps.  the fuel pump on the bus engine is shorter than the one on the industrial engine.  they otherwise look very similar but the industrial engine one almost seems to have a built in spacer.  it's sure easier to get to.  Any reason not to use it?

Pics of pumps, dirty is the bus engine, clean is the industrial engine.

Thanks, Brian

[bevans6]

Second  set of questions is about the front cover/oil pump housing.

They seem to be a pretty different configuration.  the one on the industrial engine seems to have mounting points cast in for mounting in a cradle or frame.  Internally, will they be the same or equivalent?  As long as the MCI mounting brackets clear it, is it ok to use?

Again, dirty is the bus engine, clean and green is the industrial engine.

Thanks, Brian

[Don Fairchild]

Brian,
I am not sure I understand your Question about the fuel lines. I will say you want to have fresh fuel going into both heads an then crossover to a single outlet to the return. On the fuel pumps the industrial engine has a higher volum pump and I would run it. As to the fromt cover the industrial engine has the iol pump in the front cover and if you can make the front mount work you can use it that way. The bus engine has the oil pump in the pan. If you dont want it I will take the oil pump pickup and pan if you would like to sell them.

Hope this helps

DOn

[bevans6]

Thanks, Don, that is great advice.  Interesting about the oil pumps - the pic above of the dirty front cover really kind of shows the oil pump plumbing that is described in the manual for the front cover pump.  the manual is confusing - section 1.3.5 shows the front cover and says 'front cover also serves as the lubricating pump housing on certain 6V and 8V engines" but section  4.1 says that all 6V and 8V have the front cover oil pump and only 12V engines have a gear driven pump mounted on the main bearing caps.  Very confusing, and I'm not sure I feel like taking the front cover and pan off to look.  On the other hand, i do have a new front oil seal and pan gaskets, so maybe I will.

Which is considered best, the front cover pump or the main bearing cap mounted pump?

Brian

[Don Fairchild]

I like the pump in the pan better, its a better oil pump and it moves more oil. (Higher volume).

Don