AMB

Well ran the Sharma 19 and PAW 19 today davis plane fuel

AMB

Gor a run on rhe Sharma 19 vs PAW 19 today davis palne fuel
PAW Sharma

10400 11000 MAS 9x6 blCK PLASTIC

9860 10200 wood rev uo 9x 6 1/2
8100 8200 zinger wood 10x5
then a problem shaft siezed in the bushing I took engine apart mounted crank in drill press using an 8mm capscrew the had of which
was chucked in the press and polished up with 1600 emory cloth the bushing bore was a perfect 7/16 so cleaned up the scores using that and polished it worked turns free no slop. the problem I believe was the tolerance was too close and lack of lube it is a steel bushing and if a bronze would not have happened but together and running ok Sharma does state 27-30% castor the davis plane full
quite sure at leasr 25% and has never been an issue in the PAWs. the 09 and 15 were fine on Davis fuel maybe just a quirk

SGC

Martin,
The steel bushing should give very good life, the problem was ( i think) new good fits and no pre-lube ( the motors would have been degreased after factory running, and the shaft may not have been re oiled and if any degreaser remained in the bush , it would kill the lube till flushed out/used up)
Something I allways do with a new motor or one thats been stored for a while is lube the shaft and cylinder befor starting- probably overkill in most cases.
Re results are the Sharma the first RPM and PAW the second ? There pretty close to each other and considering the Sharma is new and obviously tight!! , its No's should improve with a bit more use.
So far the Sharma's are looking good, only the life expectancy to be found , but with steel bushings the bottom end should last ok .
Stewart

AMB

Stewart think you are right on that one the engine did get a shot of air tool oil down the carb and in the exhaust port and flipped a few times befor mounting and running I also do this with all my engines and the 4 strk glows get the valve covers removed and get a good squirt and make sure some runs down the tubes where the pushrod are on to the cam. Idid notice not a drop out the front bearing of the sharma when running so very close fit shaft to bearing, when I got done the shaft shined like a mirror. I also noticed the rod is drilled oil hole bottom end, also all share the same characteristic of very low vibration so balance is good the counterweight on the shaft is cutaway on the rod pin side, liner is very nice and ports angled and very clean cuts no rough spots martin

Motorboy

The bushing are made of cast iron, not steel. The cast iron as bearing can you find to example in older pedalpowered Singer sewing machines, they are still in use in some country.

Cast iron has graphite grain and oil at place works well as bearing.

Jens Eirik

SGC

Jens,
You are correct it is cast iron , mehanite cast iron ( i think) and due to its porus nature absorbs an holds an oil film well with the added benefit of the graphite provideing some dry run lubrication.
Also just found that Carlsons is the USA agent for Sharma :- http://www.carlsonengineimports.net/...s/sharma.shtml
Stewart

AMB

Jens and Stewart thanks for the correction as I stated it was very easily fixed and bearing and crank surface now perfect\
Mr Vivek Sharma again E mailed me today takes much intrest in making sure everything right and he is sending some 8x4 props
for me to try , Very nice Gentleman

I enjoy messing with these I have many Modern conversions mainly Davis and the few from AJ which Davis does not make
sort of rounds things out on the diesel collection martin