Engine shakes excessively at idle

[Donewright]

greetings oprn,

Thanks for the reply!

Unfortunately I am the third owner. The man I purchased it from was unable to elaborate on the exact build of the engine. So I'm trying to figure it all out.

The buggy has a lot going for it and the rough Idle with a slight hesitation entering each gear are the only obvious symptoms.

The hesitation seems to be overcome by giving it more gas. Samba Members have indicated that this is a result of the 009 mechanical advance distributor and the 34PIC T-3 Carburetor being mostly incompatible.

As for the rough idle, you can see I'm still troubleshooting that one.

Would you mind sharing what you would change? I am open to any and all ideas and comments. I don't have a machine shop, but if it is just changing out parts, I can do that.

The next step I will try after work will be adjusting the carb.

[EVfun]

With no heat riser for the intake manifold I would bump the idle up to a full 1000 rpm. It is going to have a tendency to be a bit of a cranky pants at low rpm with low throttle opening.

You might have better luck in a open (and generally cold running) buggy to bump the full advance timing up to around 30-32 degrees.

One last thought is to do a quick test of the distributor. Pull off the cap and rotor and try to wiggle the shaft side to side. A loose distributor shaft can cause timing scatter. You mentioned it was jumping around at idle. That can worsen idle quality.
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[Donewright]

awesome, I'll add that to my todo list

ToDo:

Reset and adjust the idle mixture and idle speed screws on the carburetor
Increase idle RPM to 1000
Increase full advance from 28 to 30-32 degrees
Check for play in the distributer shaft

[chrisflstf]

You may have bad trans mounts also

[Donewright]

chrisflstf, thanks, I did give the transaxle mounts a visual inspection, they do not appear to be torn up, separated or damaged.

[Dusty1]

There are too many variables here to simply point at the carb and the distributor. I see no mention of a compression test. You bet it's gonna run rough if you have something like 125 (psi), 125, 85 and whatever. Or good compression on one side of the engine, loose heads on the other.

It's worth a visual inspection to verify that case savers have been installed during the long, long life of that "H" case.

I'd pop the valve covers off and see what I had for heads. 040 or 043 prefix... maybe cause for celebration. 111 or 113... they may have as many laps around the block as the case.


I'd be tempted to tear that thing all the way down. I like taking things apart. Doesn't everyone?!


Looking at the engine specs, 88mm P&Cs, 76mm crank it's a good bet it has a hi- po cam as well.

You may be able to keep your 009, add a set of Kadrons and achieve the "magical" combination someone thought this would be.

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[Donewright]

UPDATE:

I reset the Volume Screw and the Bypass screw on the carb.

I also adjust the Bypass screw and got the rpm's set to 1000.

The SHAKE disappeared!

I am also now getting readings with my Timing Light, but they alarm me;

Idle - 28 degrees
3000 rpms - 42 degrees

I think my next step is to rotate the distributor to bring the 3000 rpm value down to 32 degrees

UPDATE #2: I was able to slightly turn the distributor and the 3000 rpm value dropped down to a steady 32 and at idle is was down to 16-18

I had to adjust the Bypass screw just a little after that and it's idling at 1000 rpms with just a tiny shake, so tiny I think it's normal!!!

It idled smoothly for over 15 minutes without dying!