My 125 is driving me insane.

[ironman]

Originally Posted by Gfann

Yea I did that.
I reset the spring on one side. Looks better. I reassembled everything. Then I tried "starting" it. Did the same thing as before. Right now I'm looking at the S/G. I took it apart going through the manual about cleaning it and testing it for shorts. The interior was covered in black dust from the brushes. They are worn down. They are still about 3/4 of an inch. long. Not sure how long they should be when new or in good shape.

OK...LET'S REVISIT.....
The purpose of the ACR is to reduce compression when starting the engine to allow the starter to not have to fight the compression when spinning the engine.
The ACR does this by SLIGHTLY opening the exhaust valve. This REDUCES compression, it does not eliminate it, therefore when you had your thumb over the hole you would still feel some compression, and a compression guage would show some compression also, just not normal (say 120 lbs).
The ACR are weights attached to the cam gear and one of them has a metal tab on it that at slow speed (let's call it cranking speed) is in position to slightly lift the exhaust valve open during the compression stroke, thus you give the starter an easier job of cranking. When the engine fires, engine RPM increases beyond cranking speed, the cam gear spins faster and centrifugal force slings the weights outward so that the metal tab on the weight no longer messes with the exhaust valve and you have normal compression and a running engine.

You see the tiny spring in j-mech's picture???

That spring is almost hair like and not very strong, but it is strong enough to hold the ACR weights inward when the engine is turned by hand (or at cranking speed).

Your video clearly shows one weight flopping around when you are turning the engine by hand. THIS SHOULD NOT HAPPEN. You then say you "reset the spring on one side and it looks better". DUH, what does "looks better" mean?? Was it still flopping, or just not as much?? Did you crank the engine with the cam cover off to see if the spring stayed in place??? You discovered that something was clearly wrong, and instead of following that issue you are chasing other windmills by tearing S/Gs apart.

The spring is either broken or weak. If it is not broken you may be able to tenderly bend it through the cam cover hole to restore tension.

You gotta fix the big problem first instead of shotgunning the whole tractor!

[ironman]

Just a follow up to my previous post,,,,
I went back an watched the video of cam with cover off.
I went to full screen mode and by bumping through pause and forward you can easily see that the spring is in place on the weight that stays inward. I can't say 100 per cent, but I can't make it out on the weight that flops down as the cam rotates. Both weights should stay in place if the spring is doing it's job. This (in my opinion) was the trouble right from the get-go.

[Gfann]

Originally Posted by ironman

Just a follow up to my previous post,,,,
I went back an watched the video of cam with cover off.
I went to full screen mode and by bumping through pause and forward you can easily see that the spring is in place on the weight that stays inward. I can't say 100 per cent, but I can't make it out on the weight that flops down as the cam rotates. Both weights should stay in place if the spring is doing it's job. This (in my opinion) was the trouble right from the get-go.

The spring had fallen off, some how. I did put it back on and the two weights did hold in place like you mentioned. I could still feel heavy compression though and starter still had some drag. I was going to look to see if the tab on the weights had broken off, possibly; because it still seems as though the ACR isn't working. I might be able to see if the ACR tab is gone by peeking in the opening. I didn't think to look at it when I had it open. I'm kind of taking this situation on for the first time. no experience with this problem type so, its a slow step by step process. Also I was going to see if the exhaust valve opens at all.

[dvogtvpe]

here's a pic of the tab.

[ironman]

Originally Posted by Gfann

The spring had fallen off, some how. I did put it back on and the two weights did hold in place like you mentioned. I could still feel heavy compression though and starter still had some drag. I was going to look to see if the tab on the weights had broken off, possibly; because it still seems as though the ACR isn't working. I might be able to see if the ACR tab is gone by peeking in the opening. I didn't think to look at it when I had it open. I'm kind of taking this situation on for the first time. no experience with this problem type so, its a slow step by step process. Also I was going to see if the exhaust valve opens at all.

If you have the valves adjusted properly, then then it should be opening. But that would be the exhaust stroke. Like I said, the point of the ACR is to hold it slightly open on the compression stroke. Peeking inside, I don't know if you can see the tab or not, but I would still take another look at the spring. I think the only way to know for sure is to take the head off and watch the exhaust valve as you rotate the engine by hand. Not sure if you could tell by using the starter, might be too fast to see, but maybe.

[Gfann]

Originally Posted by ironman

If you have the valves adjusted properly, then then it should be opening. But that would be the exhaust stroke. Like I said, the point of the ACR is to hold it slightly open on the compression stroke. Peeking inside, I don't know if you can see the tab or not, but I would still take another look at the spring. I think the only way to know for sure is to take the head off and watch the exhaust valve as you rotate the engine by hand. Not sure if you could tell by using the starter, might be too fast to see, but maybe.

Currently I'm not using the s/g I'm just turning by hand to spot stuff. I'm not sure either if i'll be able to see the tab but I think if I get a bright light on it I might. Next time I look into it, I'll take off the Cam cover and breather and see what happens with the exhaust valve. I have to work outside though, its raining today not sure that I'll get out to it today.

[ironman]

Here are a couple more views of the ACR weights. This is the positions of the weights with the engine at rest or turning slowly. You can see that the tab on the one weight sits slightly higher than the low spot on the cam. During cranking the lifter is riding on the tab instead of the low spot of the cam, therefore the exhaust valve never fully closes. When the engine starts, the weights fling outward and the tab is no longer in play so the lifter can ride as it should on the cam lobe. Hope this is helping you understand.

[Gfann]

Originally Posted by ironman

Here are a couple more views of the ACR weights. This is the positions of the weights with the engine at rest or turning slowly. You can see that the tab on the one weight sits slightly higher than the low spot on the cam. During cranking the lifter is riding on the tab instead of the low spot of the cam, therefore the exhaust valve never fully closes. When the engine starts, the weights fling outward and the tab is no longer in play so the lifter can ride as it should on the cam lobe. Hope this is helping you understand.

It is, I appreciate it.

[ironman]

[QUOTE=Gfann;265881]It is, I appreciate it. [/QUOTE
I/we (all the other contributors/readers) of this long and seemingly never ending thread hope that you will not drop us when you either 'git er goin' or find some other outcome. Too many posters ask for help and disappear. Keep us up to date.

"Inquiring minds have the need to know" (go figuire?)

[Gfann]

OK. I Looked a the Cam and ACR again and the valves. The tab was there the weight looked good. as far as I can tell. I had to do some adjusting on the Valves. Got everything so it works like it should, at least to me understanding.

The ACR tab lightly bumps the Exhaust valve open, just a hair. Then the exhaust opens fully. Then the intake opens fully.

I put everything back together, tried to start it and the engine turns like it should and tries to fire, which in it of its self is pretty exiting to me, BUT I get what I would describe as exhaust through the carb throat and the coil gets real hot, so I halted my activities to review my situation here.