I have the cover off to examine the ACR system...how should the spring look?

[three4rd]

Hi,

When I crank my 129 without the spark plug in the cylinder, it cranks much faster and constant speed. With the spark plug in, however, it goes really slowly. Someone here awhile back told me that this is indicative of an ACR problem. So I have that cover off and have been examining the spring, but I don't know quite how it should look, having no familiarity with this. I see that the one side of the spring appears to be attached to the side of the flyweight, but the other side of the spring seems to be sort of on the inside part of a weight. Shouldn't both parts of the spring be engaged on the outer edge of the weights?

Thanks,
Keith

[darkminion_17]

here a pic of one

[J-Mech]

Even if the ACR is working properly, an engine will ALWAYS crank faster with the spark plug out. That is not an indication of a bad ACR. For future reference: You really didn't need to pull the cover. A quick check with a compression gauge would have told you.

[three4rd]

Hi,

Thanks for the replies in both recent threads. The one spring was not attached to the flyweight - I didn't think it should be on the other side which is where it was. I moved it over and around the weight so it looked the same as the other one. Removing and replacing the access cover was easier than I thought it would be - being that the bottom 2 bolts are not the easiest ones to get to. What was the worst was putting the points cover back on. There is that hole in the frame to get to the bottom screw, which is great, but the trick is to get the screw in the hole first. So glad it runs again. It starts much smoother than before. If it starts acting up the same way again, now I know what to do.

Keith

[three4rd]

Darkminion,

Thanks so much for these pics! I'm pretty sure in the one I can see the two springs and how both go on the outer edge of the weights. I assumed that was the right way and so went with my instinct on it.

[macman81]

J-mech, do you know what that the cranking psi should read if ACR is working? I have a hard cranking k341 I need to diagnose

[Cubcrazy]

Originally Posted by three4rd

Hi,

Thanks for the replies in both recent threads. The one spring was not attached to the flyweight - I didn't think it should be on the other side which is where it was. I moved it over and around the weight so it looked the same as the other one. Removing and replacing the access cover was easier than I thought it would be - being that the bottom 2 bolts are not the easiest ones to get to. What was the worst was putting the points cover back on. There is that hole in the frame to get to the bottom screw, which is great, but the trick is to get the screw in the hole first. So glad it runs again. It starts much smoother than before. If it starts acting up the same way again, now I know what to do.

Keith

Glad to hear you fixed it!

[sawdustdad]

Originally Posted by macman81

J-mech, do you know what that the cranking psi should read if ACR is working? I have a hard cranking k341 I need to diagnose

I put a gauge on a couple engines and cranked them--got about 50psi. presumably with the ACR working. I think it would be over 100psi without the ACR.

[J-Mech]

Originally Posted by sawdustdad

I put a gauge on a couple engines and cranked them--got about 50psi. presumably with the ACR working. I think it would be over 100psi without the ACR.

That sounds right. It had been a while since I had checked compression on one, and since there is no spec, I couldn't remember. I would say anywhere from 45PSI to 60PSI should indicate a good working ACR. Less than 45 I'd say the motor is getting weak, over 60 and the ACR isn't working right. Yes, Frank you are right on. I don't like to see less than 100PSI on a good engine. They should still start and run down to 90PSI but that is getting really weak.

[ACecil]

Glad you fixed your cub!