Advice sought on k321

**iko** · 12-31-2020, 04:43 PM

Originally Posted by david.barkey

iko, bud contact him before doing anything . - https://enginebore.com/ He is one of us and is a Kohler specialist.
Dave

Yeah it's Mike, I did!

**jamesgl** · 01-01-2021, 04:14 PM

If you are living in the Toronto area, there is a fellow that supplies parts and does machine work in Brampton, On. His name is Michael Paznar. I have recently sold him a bunch of Kohler crankshafts. Just google Michael Paznar in Brampton.

**iko** · 01-02-2021, 08:24 AM

Thank you, that's what I did!

As always, I appreciate all of your advice!

**iko** · 01-13-2021, 12:59 PM

Quick question to you guys in the know. The time will come when I'll buy a .010 rebuild kit for the STD block that's on its way to me. I prefer to buy things from local people, to support them, but out of curiousity I have looked around and see wildly varying prices, from $80 to more than $200. How does that make any sense? - is it the quality that's so different? Or simply the trust in who you get it from? Or a combination of factors?

**CobyDog$10** · 01-13-2021, 02:31 PM

My opinion:

From my GT pulling days using Kohler K's, I like quality parts in the rotating assembly. Kohler, Stens, aftermarket racing manufacturers, etc. The last thing you want is to destroy the engine by saving a few bucks on a cheap connecting rod. Gaskets, carbs, and the like, the cheap ones are fine. Just watch out for some of the goofy head gaskets I've seen floating around. The cheap fuel pumps are junk too. I did a post about those.

There are companies that sell middle of the road priced kits that stand behind their parts. Those will be fine in a stock rebuild for one of our tractors. I used one to rebuild the K301 in my dads JD 212 and it has been cutting grass for several years without a problem.

Make sure your machine shop has the piston before they bore your block. A good shop will require this since pistons have variations. Your machine shop might be able to supply their preferred kit as well. I'm not familiar with Mike but he seems to be highly recommended by the group.

Good luck on your rebuild.

**Gippeto** · 01-13-2021, 05:22 PM

Ordered the engine kit for my K321 rebuild from this fellow on ebay. It's been mowing 6hrs/week for the last couple summers and running perfectly. Would suggest the kit with the valves to save potential time. Bearings were purchased from a local bearing house.

https://www.ebay.ca/itm/Master-ENGIN...oAAOSw0W5Z~lcN

Al

**iko** · 01-16-2021, 02:30 PM

You advice is appreciated, and I won't go with the cheapest.

Got some news though. The block I got on ebay, coming from a 1981 Case 224, has arrived. I measured the bore to the best of my ability, but I have to say that it was a little difficult to come up with reproducible numbers because of the cheap telescoping gauge I have, using a 3-4in micrometer. I've repeated all measurements X and Y axis, lower, middle, and upper side of the cylinder many many times. This is what I think I got:

	X	Y
Upper	3.5011	3.501
Mid	3.5013	3.5007
Lower	3.5003	3.5006

The cylinder surface is really clean, mirror like, no scratches or anything. Assuming that the measurement is correct, I'm thinking that I don't need to bore this to .010 over, right?

Also it came with the valves, which, aside from significant carbon buildup, seem to be fine. I have no way of measuring the valve guides so, I think I'll just take them out and clean it all up good, and lap them.

I didn't pay attention the the year of my Case, or the serial number of the engine, but I hope that I can use this block with the crankshaft from the old engine.

**dundee222** · 01-16-2021, 05:37 PM

Looks well within tolerances to me. If you are getting repeatable measurements within a few tenths, You are doing pretty good! Chicom telescoping bore gauges suck and the poor metal and finish of the sliding point make it more difficult to get a perfect measure. You can score some nice vintage Starrett or Brown & Sharpe gauges for little money on Ebay. You WILL notice a big difference in repeatability as these slide smoother than baby $#it on a formica countertop.

**CobyDog$10** · 01-18-2021, 02:02 PM

It looks OK per your measurements. You will need to hone the bore so the new rings have a fresh surface to seat against.

With a stock bore in that condition, most likely your valve guides are within spec. I would measure them with pin gages to be sure though. Wear on the valve stem where it slides through the guide will give an indicator to guide health as well.

Glad to see your block is in pretty good condition.

**iko** · 01-18-2021, 09:40 PM

Alright guys, following your advice am getting a better bore measuring tool, cylinder hone, assembly oil. I'm pretty sure it only needs a hone and not boring to .010 over, but I'll make the final decision after a better measurement.

Pulled the piston out of the old block for a little post-mortem. A dent/scratch on the side, the ring ends not on opposite sides, ring side clearance 0.007 upper and 0.004 lower. The head warped pretty bad. Not sure that all this explains the bad smoke and rough running.