Battle Short

My Feedback: (5)

I recently acquired a .60 Blackhead Rossi when I purchased several planes/engines/radios locally (a Craigslist find). The Rossi was disassembled and most small pieces were in a jar, but a few were missing. The case and several other parts were severly gummed up, this may have been why it was disassembled. The piston is aluminum with no rings. The cylinder is brass w/chromed inner wall, it has 3 intake ports and 1 exhaust port. It has a single copper shim for the head that is .20mm thick. I have purchased the missing parts as well as new o-rings and cleaned everything using a partswasher that is available to me. The bearings feel smooth, I am ready to assemble and benchtest the engine, but I have a question on the assembly. The connecting rod has three lubrication holes in the journal on the crank end, each about 120 degrees apart with one centered but on one side of the rod-my question is which way should the hole face: towards or away from the crank? Typically I mark the piston so I know which way to reinstall it but this engine was in pieces when I received it so I do not know how to determine which way to orient the piston/rod assembly.

Also, what % nitro will this engine handle? All I have at the moment is 15%, will this be OK to bench run the engine?

This is my first Rossi so I am open to any advice anyone wants to give.

Thanks,
Glenn

controlliner

If you look at the lower end of the con rod, you will find that there is a big chamfer on the bushing on one side. This side will go on the crank pin first. This engine will run excellent on zero nitro fuel. 15% nitromethane will work well too. .

jaka

Hi!
Hole forward against the crank!
I would first use max 5% nitro!

Battle Short

My Feedback: (5)

Thank you for the replies.  I will put the hole towards the front/crank as you suggest jaka.  I cannot see that there is a difference in the amount of chamfer from one side to the other-not saying its not there just that I am unable to see it.

JeffH

My Feedback: (43)

My Blackhead Rossi did not have a larger chamfer on one side either. They are both equal. I marked my rod with an x before I removed, but I know you did not have that luxury. It seems as if the oil hole would be better to the rear since the intake charge containing the lube is coming down through the crankshaft then into the crankcase. It just seems that would be easier for that fresh charge to enter the rod oil hole if it was not right up against the crank disc. Of course the same argument applies since it is trapped against the back plate when the oil hole face rearward.