Advice help needed

[ColdSteel777]

Hi guys my lawn mower engine ran without oil and it threw a connecting rod so I have managed to find the same motor although a few parts are different namely the pistons and oil splasher and the one block has a lever inside that connected to the carburettor on the outside that would be the used block . now my motor did not have much use when it broke the connecting rod so I would like to use that one as d one that I bought has very worn valve guides. So I want to make one motor out of these two. I have one good crank one good connecting rod I need advice on the pistons and oil splasher. I attached the pictures for you to look at and give me some advice on which ones to use thank you

 

[bertsmobile1]

AFAIK you should be able to use the air vane governor on either block but you will have to fit the blower housing that was original to the air vane.
The oil paddles are interchangable but you will need to tie the governor rod out of the way so it is not bouncing about inside the crank case.
You should use the piston that came with the crank as they are balanced, but try weighing them against each other .
If they are the same weight then either piston should do.
However rings are a different thing.
The rings used for alloy bores are different to the rings used on a cast iron bore and should not get swapped.

 

[ColdSteel777]

hi , Im not going to use the air vane block , that one has the worn valve guides.
it turns out the piston with the flat side skirts is the newer one and its the one that came with the crank ,
although the flat skirt piston has been used a lot more than the completely round one , it has some writing on it , Ill attach a picture
hoping its not oversize.

some more research:
the blown engine(broken conrod) : Mfg. No: 098902-2101-B1
(very little useage , round piston)

the working engine: Mfg. No: 10G902-0120-B1
(high usage but still good , tapered piston skirt)

 

[ColdSteel777]

This is the piston from the working engine the one with the vane and worn out valve guides

 

[AVB]

Am afraid if you going with the 09 ci in block you would need stick to the piston and rod that are meant for it as the 10 cu in block has a different crank pin size and a different rod due the increase stroke of the 10 cu in. engine. actually there is nearly a 1/4 more of stroke on the 10 so crankshaft problably has been reposition too.

 

[ColdSteel777]

actually rods are same length , pistons are same bore , distance from gudgeon pin to top of pistons are the same. only difference is older piston weighs 200 grams and newer piston weighs 175 grams. I have had to use the heavier piston as it had the best rings. motor is assembled and turns fine. I will try to start it up tomorrow. I've got some pics and vids of the assembly if anyone is interested.

 

[7394]

Balance may be off a bit.

 

[bertsmobile1]

In that case the crank throw will be longer on the 10 series engine so the balance will be way off is you swap the crank without swapping the piston as well.
FWIW the first 2 numbers are the engine capacity in cubic inches
so a 9 engine is 9 "
and a 10 is 10"
If the bore is the same then the crank throw has to be longer on the 10" mower

 

[ColdSteel777]

well i finished assembling the motor and its running on this config:
block: 098902
piston: 098902
oil thrower: 098902
cyl head: 098902
crank: 10G902
conrod:10G902

all the other parts taken from 098902 (feul tank , exhaust , etc from 098902)

motor is running fine