Measured squish and have a question about cutting the base.

[ANewSawyer]

Finally had time to work on my weedeater, I measured the squish or at least attempted too. It looks like the squish is around 0.035-36. I did four pieces of tape, one on each side of the piston with a piece of solder on top. I used 0.032 rosin core solder and double sided taped it to the piston. Tape was about 0.004 thick. So I know I have at least 0.013-15 to mess with. I suppose the squish could be larger than that but I think it should be close enough. I did notice some gunk on the crankcase halves. Should I try to remove it? Or am I just gonna ruin the halves? The gunk could be throwing the measurement off because I tightened the cylinder bolts down.

I would like to do something to the cylinder base as I had to do a lot of work to remove the base gasket. I managed to put a couple of small gouges in it too. And a lot of work with a fine dremel wire brush.

On to the question, should I try to do the base myself or shop around for quotes to get the base cut on a lathe? I have a neighbor who has a wood working shop and I could get him to flatten a pine board I have laying around on his jointer. Use a drill press to drill a hole in the board for the cylinder flanges and glue or tape some sandpaper down. Then just rotate the cylinder around the hole. It could work in theory. What you guys think?

THANKS!!!

 

[smokey7]

I'd likely want to just motorseal it with no gasket. For ease and to make it simple. With that method I'd be sure to clean off all the old gasket on the cases. Nice job so far.

 

[ANewSawyer]

Thanks for the kind words!

My main reason is to make sure that the base is even and level all the way around. Here are some pictures. You can see I had to work the most at the corners.

On the crankcase, would you use the wire brush on the dremel and just stuff a rag down in the case?

 

[blsnelling]

Just use a new razor blade.

 

[ANewSawyer]

Worked great 'cept I used a really sharp knife. I will try to post photos tonight of the cleaned up case, after I eat though. I measured the ring end gap. 0.014 was the closest fit on both rings. The service manual says: 0.009-0.012, no more than 0.024. Kinda confusing but I guess I ought to replace them. Better than having to tear her down again.

 

[smokey7]

How many cc is this little bugger? What is the bore size? I'd probably replace them if they are easy to get. Otherwise I suspect you could get new set them up for .009 run it break it in check it at .010. So I guess I saying they not that bad and if there is 2 you are still fine.

 

[blsnelling]

Your ring end gap sounds fine to me.

 

[ANewSawyer]

24.1 ccs and 32x30 bore/stroke shindaiwa t25. The rings are listed as available on partstree. About $10 to replace both. Fyi, I measured the gap with the rings above the exhaust port. So far, I haven't seen anything in the service manual saying where you are supposed measure the gap. I agree with Brad, I would say I could run it the way it is. I may replace them though just to be sure. I plan on this puppy running a good, long time.

 

[ANewSawyer]

A pic is worth a thousand words. Needs motoseal and to replace the crank seals. Plan on trying a pick to get the seals out