Tecumseh 2 stroke

Sam69

Forum Newbie
Joined
Oct 8, 2014
Threads
1
Messages
4
Hi guys. I am new to the forum and have a question regarding Tecumseh TC300 2 cycle engine. Normally on 2 stroke engines there are pins in the ring grooves on the piston to properly locate the ring gaps, but there are none on the TC300. I wondered if the gaps had to be located anywhere in particular in the bore or would it not matter seeing as they are free to rotate. Many thanks for any replies.
 

Sam69

Forum Newbie
Joined
Oct 8, 2014
Threads
1
Messages
4

mechanic mark

Lawn Pro
Joined
Jul 15, 2013
Threads
175
Messages
7,414
Thanks for the link Mark, although I couldn't find any info regarding ring position it did mention Technical manuals, so I did a search and found one for the TC300.
All this said was to ensure the ring gaps are staggered, I find it quite unusual for a 2 stroke not to have locator pins in the ring groove of the piston.

Staggered is correct, I've never heard of pins being in ring grooves, by staggering piston rings you will ensure bore to be sealed, not letting oil by.
 

Sam69

Forum Newbie
Joined
Oct 8, 2014
Threads
1
Messages
4
Sam, What do the pins do?

Generally unlike a 4 stroke which doesn't have its exhaust/inlet ports on the cylinder wall, 2 strokes engines tend to have pistons with small pins in the ring groove to locate the piston ring gap in such a way that the open ends cannot rotate and foul on a port in the cylinder, resulting in broken rings. I have attached a link to a photograph of a 2 stroke piston with locating pins.
Scooter Help - Small Frame Piston Install

ring locator pin2.jpg
 

motoman

Lawn Addict
Joined
Aug 11, 2011
Threads
65
Messages
2,566
Sam, Thanks, never heard that before.
 

jp1961

Well-Known Member
Joined
Jul 22, 2013
Threads
39
Messages
785
My Intertec manual just has info on the TC200 not the TC300. Just says to stagger the end gaps on the rings. I'd make sure the end gaps aren't in line with any ports, if possible, as stated above. The recommended fuel-oil mix is 24:1 btw.

Jeff
 

Sam69

Forum Newbie
Joined
Oct 8, 2014
Threads
1
Messages
4
My Intertec manual just has info on the TC200 not the TC300. Just says to stagger the end gaps on the rings. I'd make sure the end gaps aren't in line with any ports, if possible, as stated above. The recommended fuel-oil mix is 24:1 btw.

Jeff

That's great. Thanks Jeff
 
Top