Shake it up!

Somewhere under 1000 RPM, sitting at a stoplight, my Speedy gets the shakes. Now I could understand if I had some huge stroker motor that was throwing it's weight around, but a stock 1600 (dual Kadrons, VS exhaust and Compufire is about the extent of "custom") should idle smooth, dontchathink?

Is this an engine thing or a frame/suspension thing? I can't remember with my other VWs in history if I got that too - hard to tell with a bus. Does your car shake too?

you live in cali... it is called an earthquake dude!

"Somewhere under 1000 RPM" ? If goes much under say 750 RPM that would be it trying to stall out due to too low RPMs.

I HAD AN UNCLE LIKE THAT, then you gave him a GIN and TONIC and he was good again....

Yeah look at the idle, mixture. You should be able to get a relatively good 850-900 idle with minimal shakes.

I'll take a stab at it.

It's obviously in your engine- the frame/suspension isn't doing anything but being a big-'ol lump of metal when the car is sitting still.

I'm guessing the needle and seat valve in one or both of the Kads are leaking by and causing the bowls to overfill and flood one or more cylinders. Kadrons have notoriously bad needle valves (no rubber on the tip of the needle).

Does the car sputter and spit for a couple of seconds after the light changes, then smooths out as you get going? If so, you can try lowering the fuel pressure to give the needle and seat a fightin' chance. Don't expect much.....

Well I first checked the obvious to eliminate those ideas... USGS says no big earthquakes near me this week, and two gin & tonics in the tank didn't do the trick. (but I do appreciate the wise cracks!)

It seems to idle okay where it should (650 - 800) but anywhere under 1000 I get the shakes. I don't get any sputter when accelerating off the line. Technically speaking, is this an inbalance of fuel delivery that kicks every other cylinder a little harder/weaker?

I'll try the easy solution of carb cleaner in the tank a couple times before I go on to more exhaustive efforts like rebuilding the carbs, or securing the earth's tectonic plates.

I would check the idle balance on the carbs and the mixture screws. It sounds like one of the cylinders or perhaps one side is not matched to the other(s).

After getting it tuned in at the idle speed, don't forget to balance at 2500-3000 rpm.

I'd also bump the idle rpm up to 850-900 rpm.

Jarco,

I agree with the Dale, You need to balance both carbs so each is pulling the same amount of air. Also, you probably need to adjust the mixture setting so each is getting the same amount of fuel. To do this, you'll need a carb balancing tool and 2 different types are available. The Uni syn and the "snail" both work equally well but the snail is easier to use. If you have Kadrons, you may have to make an adapter to fit on top of the carb so the syncronizer will seat over the carb.

Try for 850 - 900 RPM's at idle.

Also, check your timing. It should be set when the engine is turning 3,500 RPM and should be set at 28 degree's before top dead center. If you have a Bosch 009 distributor, check the to see if the centrifugal advance plates are working smoothly. (Grab the rotor and twist, if it moves easily the you're OK but, if it has drag, you'll need to disassemble the distributor and lubricate the weights and springs. If you find old grease in the bottom of the distributor, clean it out and re-lubricate everything)

Jarco,

I was looking at your pics. One of them has your old engine, that has two round cut-outs on the side of your fan shroud.
What were they used for?

Bryan

So I guess it's just tuneup issues on the carb - makes the most sense. I have a SVDA distributor with electronic ignition and got the timing set like you said there - I think we're good there.

Those cutouts were a mystery to me - never seen anything like it. There were no cutouts or anything in the engine compartment. My guess is a previous Dune buggy app or something with some pipes or hardware up and around there. Not sure of the engine's history, but surely some kind of funky deal with that huh?

SVDA? Did you pull the vac. line off the distributor and plug it whilst setting timing?

Jarco, Did this problem just appear now? What is the last thing or adjustment/change you made prior to the problem?

I'm guessing your carbs are not matched and one carb throttle plate is almost closed and the other side is carrying the engine at idle.
Pop the air cleaners off, take a peak. Also have your pal sit in the car press the throttle to see if both carbs go to "full" open.

I can't recall if the problem "just appeared" as I haven't had the car for about 6 months in the shop. I suppose there's some varnish in there from sitting so long and it ran horribly at first. But after a few tanks with carb cleaner in it, we're back to smooth except for idle.

I'll try all the adjustments again at 900RPM and see if I can get a little better balance at idle - sounds like the answer.

Have you cleaned your idle jets and idle circuits?

Pull the idle jets out and blast them with carb cleaner, then remove the idle mixture screws (watch out for any o-rings on the screws, if they have them) and blow out the passages with 20 lbs. of compressed air. Shoot some more cleaner down the wells where the jets screw in and blow out the air mixture passages again, then put everything back together and re-set your idle mixture screws.

If that, and the carb cleaner you've been running through the gas tank, don't cure it you may have to pull the carbs apart and do a clean and rebuild on them, as they may have some varnish in there that won't come clean.

gn

Ever hear of STABIL?