Ldalmas

I am thinking of converting a os max 15 ( the side draft one) it is still new and since i have abandoned glow it finished redundant, i was going to fit the contra piston on an ofset to the center because of the blade on the piston what do you think?

gcb

I am assuming that you have a baffle pistoned engine such as the Max-III .15. You stand a chance of rotating the contra when you make adjustments so you would need to make some kind of pin mechanism in the head to prevent rotation. I think OS did that with their diesel way back before schnuerle, or even flat-top pistons were used. Their diesel was a bit more robust than the glow and was only produced for a short time.

I would suggest selling the glow or just putting it away and buy a purpose-built diesel. The conversion you suggest is not an easy one.

Don't make your decision on one opinion, though. Wait for more responses. Perhaps someone has tried this conversion.

George

Ldalmas

i have made the convertion but i still have to try it out. i have left the deflector on the piston and made the contra on the large part of the head and it is abour 8mm diamiter (the max i could fit ) and gave it some travel so it should work.
Laurence

Ldalmas

i have tryed it with a 9x6 mas and got 9200 not bat for a side draft engine?

SGC

Ldalmas,
The OS Max3 is ported to produce its power at higher RPM's, its not a motor that like big props- see test report. I would use only a slightly larger prop than recomemded for glow on your diesel , probably a 9X4or 9X5 as a max prop for it to produce good power.
Stewart

Ldalmas

SGC do you have the manual for it ? cause i do not have i found the engine in a junk shop and took it because it is in a verry good condition
Laurence

SGC

Ldalmas,
Sorry no manual, i purchased mine new in about 1970, box and paperwork are long gone. I still have the motor, and its still in good condition after much use.
Stewart