LO206 Short Block

Mulling the idea of picking up a new short block. I believe the motor on my used kart is from 2015 and is a GT Machine and has the holographic seals. Previous owner said it was just freshened up when I bought it although I can’t confirm that. It runs perfectly fine but with the scarcity of 206’s around and the fact that used builder motors are fetching over $1000 I wouldn’t mind having a backup.

My lower end potentially being 7 years old and god knows how many hours on it could be due for an upgrade to the orange seal newer block. I can grab this short block for $375 plus the ride. Couple of questions. How difficult is it to swap the flywheel assembly?

It appears it’s a tapered shaft. Is that something anyone here has ever done? My initial thought is to swap everything over from my current motor onto the new short block. I’d like to have the valves and springs replaced and make sure the seats are cleaned up by someone like TS Racing. If I can come in around $700-800 all in, I’d feel better than plunking down $1000 plus for a used one and know that I pretty much have a brand new motor.

The difference saved could go towards other kart related things like a sniper, rear axle, tires etc. Thoughts?

To your original question, its not hard to short block a 206. Nothing difficult about pulling the flywheel. I believe there may even be a youtube video or 2 out there.

However, without knowing how much time is on yours, you have no idea what kind of shape it is in. Have you done a leakdown? Put it on a dyno? I would send it to a reputable builder and get some recommendations first. The best engine I have ever seen was a black wire seal I did last summer. Don’t guess that you need something. Find out IF you need it.

For the prices you are quoting, you should be able to send it to someone and have them do everything for you (short block replacement, head and carb rebuild, and dyno tune).

Everything from here down needs to come with the disclaimer that I work at Ghost Racing as it sounds like I am advertising.

Just for reference, we do all of that as part of a short block replacement and charge around $600 plus shipping. We would get your engine in its current state, leak down, dyno, and do a health check before replacing the short block.

Lastly, if you can find a new engine from a reputable builder, go that route. With your current plan. $600-$800 and you could have a brand new engine with a used head that has worn valve guides and sunken valve seats. Or for $1000 you could own a brand new engine and keep your spare for rain racing or practice days. OR even better, you could sell your old engine for $500 and buy a brand new one for $1000 and only be $500 into your brand new engine.

I think having a spare block is prudent, but at the same I think having a leakdown and compression tester in your toolset might be even better so you can diagnose and/or pinpoint issues.

Usually the valve seats are the first thing to go that causes a drop in power. Come to think of it, you don’t even nessacarily need a leakdown tester to check of leaky valves, you could just apply compressed air and listen in the ports for leakage. This can be done at bottom dead center for safety.

I have a compression tester but didn’t think I could use it due to the releases. I’m wondering how many rpms are required to trigger the release cams? I’m assuming get my drill driver on the clutch bolt and try it? I’m pretty crafty and making or buying a leak down tester is a tool I would like to have in my arsenal. The motor currently feels like it runs strong and there’s no issues with it. I just don’t like not knowing it’s real history and if it’s time to consider a fresher bottom end. I guess I could also put my bore scope in there and look at the cylinder walls for cross hatching or yank the head for an up close look just to ease my curiosity. Going out to the garage and working on my kart is actually quite enjoyable and my form of therapy. I crank up some classic rock and can spend hours just tinkering…but lately I’ve kind of run out of things to do to it, lol.


We don’t replace short blocks unless we screw up and chuck a rod from ignoring the no oil sticker or we broke a compression release. :man_shrugging:t2:

@CrocIndy But what’s a realistic life cycle of a 206? Just running it till it’s flogged like an old horse and then having to find one is something I’d rather avoid. If they were readily available, I wouldn’t be as concerned. But with the current shortage, or having to overpay I’d rather be proactive versus potentially being on the sidelines for weeks. For local club racing and owner days, I honestly don’t really need an $1100 “builder” motor. Not that I’m from the cheap seat section…. I just don’t plan on running Grands or anything other than just as a fun hobby and think some motors are a little overpriced for my needs. I’m sure we can agree that the price has gone up substantially due to supply issues.

Yeah you can spin it with a drill (or an external kart starter if you feel like getting one). Better to spin via the flywheel nut vs clutch bolt. I think it’s a 22mm.

That’s what I realized after I gave it some thought. Clutch side would be loosening the bolt so I’d need to hit it from the recoil side :+1:t2:

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