Toss the Kehin, Toss the oil injection- ETC 250 ET is a new sled.
Hi: I just found this forum and this thread:
I thought I would share some stuff on a project I finished this morning, not really bragging, it took way too long, started this fall, My grandson got a pretty minty looking ET 250 to drag race and ride two winters ago, well it nearly drove my son and I over the bend, would not run right, one time would start-- next time not, sometimes ran great. went racing in Earl Grey last Feb., couldn't get it to start, missed his class. took it home started right up and Grandson rode all over. My son took apart kehin cleaned , set fuel level replace pulse line , all these things a feat to do if you have ever worked on ET with oil injection. Anyways he brought it to me this past fall. well about that time I stuck my finger in a meat grinder so never got at it. Xmas came and family was home but worked on Son's thunder jet. So yesterday I said that's it ET will be fixed. Took off kehin carb, thought about it and tossed it. . Tried to see if seals were leaking couldn't even see PTO seal because of oil pump, couldn't get recoil off without taking off oil injection tank, pulled engine, thought about oil injection-- took off oil tank-- tossed, took off oil pump-- tossed, now we are getting some where , PTO oil seal shown in pic below. So problem solved-- well not completely, the ET has a filter in the fuel tank on the fuel outlet fitting, you can't even get to this till you remove the oil tank. Well filter had never been changed in ET's life and, had collapsed from suction as was full of yellow varnish and other stuff-- tossed filter. Now mounted on oil tank is a fuel shutoff in main fuel line with a toggle switch on dash. Be dammed if this wasn't seized only about half way open, cable moved but fuel shutoff did not. --tossed this. Went to my good used parts, selected a pretty good looking 34 mm carb, Cleaned and good used parts in it , mounted a nice cleaned used single fuel pump (off a sno jet) gotta be a good one. new choke and throttle cable, took a wee bit of throttle block mod to get it to idle and open full . Here are jets and parts I ended up using in carb. Started out too rich, didn't really have much to go by, Yamaha never used a micky on their little single.
Main jet--220 -- think it's still a bit rich.
Needle jet--159 05
Needle 6DH7 have it in three, may need to go up one.
Piolet 30-- seems to idle good and throttle response is good
1.5 inlet
2.5 slide,
Anyways pleased with how it turned out, hope this post can help someone thinking about doing the same thing. ET starts with one pull in shop. left it outside overnite took two pulls with choke, and goes faster than Grampa wants to go anymore . If anybody has any tips, comments or questions please do reply. Feel a little bad about tossing kehin, don't think there was any thing wrong with it. Cheers Jack
PTO seal--rotted right out in oil pump housing
Tossed parts
Made bracket and mounted fuel pump on fuel tank where oil tank had mounted.
close up
out on the snow
