Boll Aero exhaust port question

[kita]

Hello, my name is Jeff, in Michigan. This is my first post to HMEM.
My question/problem is..... I drilled the exhaust port hole a couple drill sizes to big (on the cylinder sleeve). I know......how did you do that? Does anyone know how much of a problem this is? Will it work? Should I remake the sleeve? Any thoughts would be appreciated. This is my first diesel. I have a steam engine under my belt (wobbler) .
Thanks guys.

 

[kf2qd]

How much too big?

And was the center of the hole at the correct distance from the top of the sleeve?

The important detail on that hole is the top edge as that controls when the exhaust port opens. Opening early will mean a bit less power.

If the hole were too small that would be better as then it could be opened up.

Does the exhaust port open before the transfer ports?

 

[kita]

yep hole is centered in correct dimensions. hole should be a no.16 drill, I did a no.12 drill. (I don't know the decimal conversion off the top of my spinning head) so a few thousands bigger. And yes exhaust port opens before transfer. I think I will finish it and see what happens? This is all about learning for me (and fun). thanks for your reply kf2qd! The cylinder sleeve is all most done, need to lap. So I hate to have put the work into it and have to start over. however if it is incorrect, so be it. more practice, right?

 

[Mechanicboy]

If the distance from edge of sleeve to exhaustport is not correct, use needle file to file until distance is correct. Correct timed engine will make starting the engine easier.

 

[kita]

top of sleeve to top of exhaust port? correct timing and ease of start makes sense. thanks. I will take any and all advise I can get...........

 

[Mechanicboy]

top of sleeve to top of exhaust port?

See at the drawings of the sleeve where distance is measured between edge of sleeve and exhaustport, if there is distance from top of sleeve, take a measure and adjust with needle file to correct distance. Do it same with transfer port and inlet port.

 

[kita]

I understand..... thanks Jens Eirik !

 

[gus]

Please post video of your running when completed.

Two stroke engines can be very unforgiving when fits and dimensions are not to print specs..
Good reason why I went 4 stroke which is quite forgiving.