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Fri Nov 11, 2016 8:22 am

I had replaced my Ghia's 017 distributor with my 009 distributor the other day and noticed that I had a low-end hesitation again, which is why I installed the 017 in the first place. I did not have any hesitation issues with the 017, but adjusting timing with the vacuum can was difficult.

After I had engaged the bottom of the 009 with the distributor drive shaft, I noticed that I had a lot of rotational slop (~22 degrees). I have another 009 in the 40HP in my ragtop (no hesitation) and I measured the rotational slop to be ~11 degrees.

To figure out if the slop in my Ghia was due to that particular 009 or some internal engine issue, I swapped distributors. Odd thing was that now both distributors had the same rotational slop (~11 degrees) and I could not isolate the issue, but I'll take the solution anyway.

In addition, all hesitation is now gone and the Ghia engine performs smoothly now.

I bring this up because this may explain unsolved low end hesitation issues...

Best,
Thom

Fri Nov 11, 2016 9:13 am

Go to the 009 take the little cap off the side and spray in some light machine oil. What you are probably seeing is a lack of lubrication under the centrifugal advance weights.

With years of grime the nylon sliders get sticky so the advance jams either at idle setting (stumblel) or full load (back lash and too fast idle..) The springs are not strong enough to pull it back to zero.

And setting up the idle timing and full advance onthe SVDA you take the vacuum hose and block it off. Should not be sucking at idle bt if it sucks your carburettor throttle plate is set wrong. Then go for the 28-30 degrees at 3k rpm.

Fri Nov 11, 2016 9:20 am

mikedjames wrote: Go to the 009 take the little cap off the side and spray in some light machine oil. What you are probably seeing is a lack of lubrication under the centrifugal advance weights.

With years of grime the nylon sliders get sticky so the advance jams either at idle setting (stumblel) or full load (back lash and too fast idle..) The springs are not strong enough to pull it back to zero.

And setting up the idle timing and full advance onthe SVDA you take the vacuum hose and block it off. Should not be sucking at idle bt if it sucks your carburettor throttle plate is set wrong. Then go for the 28-30 degrees at 3k rpm. I agree...although I dont understand the slop your refering to. you could recurve it so it has a smoother addvance.

Fri Nov 11, 2016 3:32 pm

The slop I'm referring to is that even with the distributor fully engaged with the distributor driveshaft, you can still turn the rotor ~11 degrees until it stops and then returns to place after being released, as opposed to being rigid and not being turnable at all WRT the position of the distributor driveshaft...

Best,
Thom

Fri Nov 11, 2016 4:16 pm

Quote: degrees until it stops and then returns to place after being released,

I thought this is how a mechanical advance behaved. :?

A mechanical advance distributor engine has to have a larger accelerator pump squirt.

Fri Nov 11, 2016 5:47 pm

The "slop" you describe is supposed to be there. The one with the 22* "slop" is about right. The one with only 11* "slop"
has something wrong with it, since 009 distributors are supposed to have about 20-23 degrees of mechanical advance.

Fri Nov 11, 2016 6:08 pm

I'm aware of how mechanical advance distributors work and that the slop that I have described is supposed to be there.

I'm just describing my methodology and observations, in that the 009 with the 22-degree slop (with twice that of the 009 with the 11-degree slop) appeared to be causing the hesitation, as a possibly rare cause of hesitation that might be overlooked when other Sambanistas are trying to trouble-shoot a non-smooth running engine.

The 009 with the 11-degree slop did not cause any hesitation at all...

Fri Nov 11, 2016 6:45 pm

Having to compensate for the hesitation is why the 009 is disliked.