Well, John, glad to hear it has improved, and you still have your license!

Otay, back to the timing chain thought.
When you're driving down the road, there is tension on the timing chain on one side of the timing gear. When you let off the gas, the tension goes away. Now...if there is a lot of play in the chain, as in worn out, when you let off the gas, the crank speed slows up instantly, but it takes a second for the timing gear to slow, due to the slop in the chain. Then you gas it again...the crank moves forward in it's rotation, but that dang chain has let the cam gear lag behind a second or so, retarding the valve timing, as well as the distributor timing, since the dist. is geared to the cam. What happens? Well...you get a bit of hesitation, until everything catches back up to crank speed.
(I'm sure there's a better, more technical way to put this, but...I'm just a dumb ol' farm boy, and that 's the best I can do!)

This is one of the main reasons I caution folks about using the engine as a brake for the car. When you do that, it creates a lot of stress on the timing chain by forcing it to take the force of the rotation of the cam gear in one direction("pulling"), and change it("pushing").

Dang...where's the Zen-master when ya need him? Adams' Apple2007-12-21 20:16:08

So what is the easiest way to check the timing chain?

There were 2 questions in that last post....lol

John,

Dave, no it didnt do it out of a turn anymore.

if your parts store has it, you may want to try lucas gas treatment. have had really good experiences with it cleaning out the insides of the carb while you drive. 

Thank you.

John, Gumout makes an inline carb cleaner as well that can be poured into the tank.

So, I am guessing that you are ruling out the timing chain at this point due to the improvements to date.

If you get to a point where you think you might replace the Q-jet I have a wayward home for Q-jets in my garage and would be interested in yours joining they current attendees.(at my cost of course)

Hmmmnnn, I guess my last option of my 1st post won't materialize..... an I was thinking how nice that red vert would look in my garage against black & white vettes .....    

[QUOTE=jt's73] So what is the easiest way to check the timing chain?[/QUOTE]

For anyone who wants to check it for whatever reason, here's the only way I know of, short of pulling the front cover...

Remove the distributer cap first. Then, you need some way to turn the engine back/forth, by hand. This is always much easier to do with all of the sparkle-plugs out, but it ain't absolutely necessary.

Turn the engine one way, until the rotor on the dist moves, and then mark the position of the rotor tip, AND the position of the balancer. You can use a marker, or white chalk, or whatever to mark the balancer, as long as you line the mark with a stationary object, like the timing mark on the front cover, or just a bolt...

Now, while watching the ROTOR on the dist., turn the engine back the other direction. Notice when the rotor starts to move, then stop turning the engine. Look at the mark on the balancer. If your mark has moved more than 1/16th of an inch, the timing chain/gears are worn. I've seen some that moved over 2 INCHES before the rotor turned.

All chain/gear set-ups will have SOME slack...what we are looking for is excessive slack. When new, full roller chains will have the most slop in them, while the normal, rocker/pin types will have almost none.
If your engine happens to have the nylon covered timing gear on the cam, the nylon will eventually break off, leaving the chain with an extraordinary amount of slack, causing the chain to "jump" over the gear teeth, resulting in a cam/crank out-of-time scenario. This usually leads to an engine that won't start, or might start, but won't stay running. Think of it as a really loose bicycle chain, that keeps slinging off of the sprockets...

Hope this info is of some use.


another thought on timing chain slop...IF you have an engine that has been "align-bored", you now have another problem. When align-boring an engine, what they are doing is removing metal from the main bearing saddles of the engine, in an effort to make the main bearing bores as straight(frt/rear-up/down) as possible. The problem is, when this is done, the crankshaft centerline has now been moved closer to the camshaft centerline, which means the two items are now closer than normal. Now, if you install a timing chain, the chain is loose to start with, because the two gears on the crank and cam are closer. Now what?

Some machinists say it ain't all that much difference, but I happen to diskagree. This is where running a gear drive is best....Adams' Apple2007-12-23 09:25:39

Seems like you've gotten a LOT of good info here. However, EVERY TIME I've had an accelleration hesitation problem on a Q-Jet equipped car it's turned out to be the dang accellerator pump. The gumout might indicate something else UNLESS you sprayed some on the top of the accellerator pump seal itself(If you did that might have temporarily swollen the accelerator pump seal and resulted in your current improvement).  Replacing the pump itself is cheap and easy and becomes only a little more expensive if you go with a complete rebuilt carb.