Jim, the engine is completely stock as far as I can tell. I never seen another one of these machines on the road, but in comparison to the manual, everything is there the way it should be, although I can't comment on the jets in the carb, those might be different.


My best guess at this is that the engine is overheating because of bad mixture, or the wrong kind of plug is in there which can't handle the heat. I have no idea if plugs fail, but I had a spark tested on this one and the spark just started dissapearing. I don't know if too much heat cuses the spark plug to fail, I got a colder plug and I will try it out.

The oil temp light never came on the machine, so I'm guessing that the engine never did reach a temp where it would self destruct, however the manual does state that plug selection is rather critical for air cooled engines. Again, no mention of what happens if a bad plug is selected.

If it's none of these items, then I guess the cylinder and piston are shot, and they have to be overhauled. I have no problem with that, but first I want to be sure that this is indeed the problem. I'm taking my compression tester up north this weekend, I will hook it up and see what it tells me.

I have to look into getting a leakdown tester and a valve spring compressor.

Looks like I got me a lemon.... but other then that, this thing is really great for chores around the cottage.

Thanks much every and keep the suggestoins coming, even if you have a hunch you might know what causes this.

I have yet to meet a spark plug pro

xp

__________________
1985 190E 2.3L - a constant project.

Have you replaced the ignition coil?

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I'm sick of .sig files

Yup, got a new ignition coil on it, new CDI box, new Stator and pick up coil, the only thing left is the wiring, and naturally spark plugs have been swapped, but it was probably a plug rated for the same temperature

I'm not an expert on spark plugs, but I have a theory that the current type I'm using overheats and due to overheating stops making the spark, would it be because of of conducting or some other reason. I got a colder plug, I will try it and see if there is any difference.

If anyone knows anything about how spark plugs behave outside of their operating temps, I'd love to hear it, I can't find anything on the subject.

TIA

xp

__________________
1985 190E 2.3L - a constant project.

Figured it out.... it was the spark plug boot.... I didn't even know they break.

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1985 190E 2.3L - a constant project.

Thanks xp! LOL!!! You made my day!!!

It's ALWAYS the simple and least expensive part that causes you to go out and buy the most expensive and complicated pieces of the whole machine, isn't it?

It's the same way in electronics...if you see smoke or smell "stink" - that's the sign that the item won't work...everyone knows that electronic components are manufacturered with a little "smoke" and "stink" inside each resistor, capacitor, IC chip and wire. If you see the smoke leaking from the component, it's a "guarantee" that the part is failed. If you smell "stink," same thing. (The "stink" is what the component manufacturers put into each part so if you're in the dark and can't see the smoke, the "stink" will let you know - sorta' like the "rotten egg" smell you have with natural gas...only you don't need to run from the electronic "stink." )

I guess that being outdoors, with all that fresh air and the breezes, you couldn't possibly have caught the smoke and stink from that spark-plug boot's failure...

Hey, enjoy the ride...You've earned it!

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M. G. Burg
'10 - Dakota SXT - Daily Ride / ≈ 172.5K
.'76 - 450SLC - 107.024.12 / < .89.20 K
..'77 - 280E - 123.033.12 / > 128.20 K
...'67 - El Camino - 283ci / > 207.00 K
....'75 - Yamaha - 650XS / < 21.00 K
.....'87 - G20 Sportvan / > 206.00 K
......'85 - 4WINNS 160 I.O. / 140hp
.......'74 - Honda CT70 / Real 125
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“I didn’t really say everything I said.”
. . . . . . . . . . . . . . . . . . ~ Yogi Berra ~