Tecumseh won't run past half throttle

[bgsengine]

On some blowers you can flip the gear selector shaft lever and use a single pulley engine and still get the multiple forward

But, often the camshaft pulley, which rotates in opposite direction and at half speed, is used for *reverse* gear (power reverse) So, if the unit has reverse or other feature which uses the second cam pulley, it isn't about speed selection. However, if there were sufficient space to engineer with (or removing the belt shrouds to make an "ugly mod") it is also possible to rig up a shifting pulley contraption to run the back side of a second belt on the crankshaft , thus giving a reversing direction of drive from the same crank rotation.. but I digress...

[bgsengine]

If I put rings in it would have to hone the cylinder first. I didn't take this to sell but thought it would be fun to use but I can't afford the space in my shed if it doesn't run.

I'd have assumed the bore would have been checked at least cursorily when the head was off- If so, and it seemed OK, then you can get away with just putting rings in it - Bore does not necessarily need to be honed, especially if you can see even faint traces of the original cross hatch pattern..

Thanks bgsengine for the reply. Lets start with the cylinder. Since I only do this for a hobby on my own equipment, I've never done any honing. I've included a link to a picture of my cylinder to gets your thoughts. What are the lines going criss cross on the walls?
https://photos.app.goo.gl/5rCSdt4EFqMXmajz6
Thanks for any input on this.

Hard to tell from your picture, whether those are natural (in raised relief due to your camera/photo quality/angle of the shot) but yes the *PATTERN* those criss cross lines are what I referred to as the cross-hatch pattern , however they are usually much more close together (freshly done at the factory they may resemble a mesh garlic bag pattern)
Your bore does look pretty clean otherwise, not anywhere near as bad as might be expected for a "condemnation" of suitability. Also, if the engine really is not using much oil (if it gets dirty fast that means there's something INSIDE the engine that is contaminating it) and only puffs of smoke now and then, I would not be expecting it to be a ring problem in the first place, but if you could get a clear picture like that of your valves and valve seats (roll piston to top center, pull both valves and set each one on its head next to the seat, for example) as they are (don't clean them off if they have any dirt or carbon) we might have a better idea of condition of your engine

Finally, I can see what almost appears to be a bit of piston ring between piston and cylinder wall, and if that is the case, your bore may just be quite worn, and like Arkie said, could be someone before you got "into" it and tried to fix it up , "just good enough to sell it" , thus passing off the inherent problems with the engine off to someone else (possibly the one that ended up getting rid of it and putting it in your hands?)

But that aside - IF you can see the top piston ring in the gap between bore wall and piston, see if you can see the compression ring end gap, if it is big enough you think you could measure it with a ruler - as in bigger than breaker point gap size, then either rings are worn out, or bore is worn out.... What you could do is if you get a ring set first of all (still relatively cheap, I believe) you can take rings out of the box and fit them in square (using piston to square them up) and measure end gaps with a feeler gauge... if they're still in spec, you can just re-ring, because as I mentioned that bore looks clean enough that *IF, AND ONLY IF* the engine does need new rings, they can go in and seat quite well in a bore like that, assuming the cross hatch marks we see in the photo were not deep scratches caused by someone that didn't know what they were doing with a boring bar....

[Arkie]

bsengine: Good eye about lots of ring showing on one side of the piston in the bore.

AND lots of ring showing on one side of the piston in the bore in your picture needs to be carefully checked.

That is not normal, especially with a piston down in the bore.
Might even be little worse at the top or bore. The bottom of bore is smaller than top on a worn bore.
Cylinder may be honed excessively wrong or maybe a Bubba in training project. (school tech training project)
Sometimes you can find a machine shop that bores engines and they will mic and check a bore and piston for next to nothing or a School that teaches small engine repair.
Or like bsengine says use the piston to check with a new ring inserted into the bore, but this will not detect a oblong egg shaped bore.

If the piston is still round you can use it in the bore to check side clearance just to get a general idea if the bore is still round.

[Roadrunner123]

Update: Just thought I would throw this out. Second day in a row I've done this, Start up the snowblower, let it run for less than a min at less than half throttle and it will then run right up to full speed. It seems like when it idles it may be burning the excess oil but the ratio to gas and oil is different at low speed which could be causing more soot on the valves and thus causing this issue? Any thoughts on my theory?

[lefty]

I have an HMSK85 here. I'm not sure if it will fit that machine but it's got the additional cam pulley.

She needs some love though. Came here allegedly seized but it turned out to be stripped starter bolts that jammed up the ring gear. I cleaned the carb and got her running but she pops a bit and may need some valve work. I was going to do a leak down on it before diving in but in the event that your original engine is a lost cause and this one fits, give me a call. I'm rooting for that original one though. I know you'd like to save it if possible.

[Roadrunner123]

thank you Lefty for the offer but I think 8hp would be a little overkill, this blower is like a toy. If I can't keep it orginal, I will just part it out.
Thanks again for the offer.