4 stroke advice please

Jun 21, 2004 4 Replies
L

Just been trying to set up a new SC120 4 stroke for my son in a P51. Had a few tanks through it now and it seems OK but I'm a bit worried about the needle valve setting? It will only run OK with the needle about 1 turn open. Is this right? I always thought it should be about



2 to 2.5 turns. We ran it in at about a 5 turn setting and have slowly closed this down as it ran in. Idle is fine and it seems to go to full throttle fine but changing the needle valve doesn't seem to do much at all. I've only ever set up 2 strokes before and I know on them that setting the needle valve changes the engine speed quite a bit.

TIA


cheers, Len


Vote
Twitter Facebook LinkedIn
P

It is OK to run the engine at the setting where the engine runs the best. The number of turns out is completely irrelavent unless it changes drastically.

Vote
Twitter Facebook LinkedIn
L

Paul, Thanks for the info. I've just put another tank of fuel through it and it runs perfectly, tickover, full bore with the neddle vale about 3/4 out!

Gonna leave it like that as it seems to run just fine.

Thanks

cheers, Len

Vote
Twitter Facebook LinkedIn
R

Wouldn't suprise me in the least - about normal for them ~(but whatever you do make SURE you are running rich).

Vote
Twitter Facebook LinkedIn
R

I agree competely. you should see a nice smoke trail- at least I do down here in South Florida. Recommend that you set your RPMs with a tach or temp gun, not your ear. Good luck with it. Andy

We can make a box of wood.....FLY!!

Vote
Twitter Facebook LinkedIn

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required