Sync Carbs

[Justin Case]

When I syncronize my carbs, my gauge reads 18 kg/h on both carbs at around 900 rpm. I have checked and replaced the intake manifold gaskets, the crossover hose, and looked for cracks on the manifold. I rebuilt both carb with all new gaskets. Adjusted the valves and rechecked them again, and did a compression check and had 150 on all clyinders. The carbs balance out, and it runs smooth. I have sprayed either on the shafts with no effect. Any suggestions ?

[Jimm391730]

While I guess that they had to put some sort of scale on the syncronizer, I don't even look at the value beyond matching both carbs for the same flow. As long as it idles well (and that is all the syncronizer is good for, idle conditions) and both carbs draw the same then you should be in good shape.

[edzz]

From what you have written it sounds like I’d drive it and enjoy it. I’m not quite grasping what you think is a problem.

[Justin Case]

I was just curious what other owners thought, because most of the desired reading posted are around 9.

[krick3tt]

I'm happy if they match...to me that is balanced.

[Roverchef]

So what ya'll are saying is that the #'s on the sync meter don't really matter as long as you can get the carbs the same on the meter? Why we're on it...would you sync the carbs 1st and then mess with the mixture screws 2nd in order to get the rpms that you want?

[Jimm391730]

The carbs are sync'd to ensure that all four cylinders are pulling equally at idle; then the mixture screws are ajusted for a certain RPM change. These are slightly interactive, but if they are performed in the proper order then the effect of the second adjustment has less effect on the first.

For example, changing the points dwell will change the timing, but changing the timing does not affect the dwell.

Follow the order in the manuals and adjustments will go easier.

[Jim LaGuardia]

Make sure the rubber part of the sync tool is not covering the side vents or you will see high numbers(rotate rubber to adjust). The air holes on the side of the sync tool must be fully open.
And yes, sync first, then fine adjust idle screws and re check.

[Roverchef]

Oh...I read the manual. Only reason I asked the ???'s is that I sync'd the carbs and then adjusted the mixture screws to get the rpms @ the # that I wanted. It idles perfect @ around 900-925RPMS with the carbs sync'd @ 9 and the timing @ 10BTDC and and whines-up super smooth. I am just not sure if it is running too lean. I'm trying to get the 5-gas analyzer up and running but it may not happen for awhile so in the mean time I was looking for answers to the white/blue smoke I get on start-up and then it disappears after about a minute. It only does it when it's cold! I thought maybe the chokes were stuck on and after investigation and a new cable I noticed that they don't retract without help from my assistance and I even put a stronger spring on them. Without the cable attached the levers seem to be sticky and tough to turn. They were like this before the rebuilds too. Should they be this tight? OPPS...Sorry 'bout the hi-jack!!!

[krick3tt]

I am sure they are out there but, I have not seen a pinz not smoke on start-up...especially when cold.

[pcolette]

My Pinz has always smoked at start-up in the cold for the first 1-3 minutes. I believe it's just the nature of the beast and its particular choke mechanism. The chokes on all 3 I've owned have been stiff and required constant assistance to close. Even brand new choke cables are stiff. I've found it's just a matter of getting used to the particular quirks of your truck.

[Roverchef]

GREAT!!! I thought all of ya'll had figured out how to make a 30+yr old rig not smoke on start-up! Don't get me wrong...I know about quirks on rigs. I was more interested in the sticky choke mechanisms and wondering if this was normal. Thanks for all the input/answers and making me feel like part of the "club"! I guess if it didn't smoke I would be outta place.

[Stekay]

Not sure if you've noticed but about half way down the choke cable, there's a fitting on the sheath to lubricate the cable. I shot some Kroil down it and it helped a bit.

[pcolette]

Yes, that fitting is one of the regular maintenance lube points but I've tried (at various times) Kroil, Military petroleum jelly, Militec gun oil, etc. and like you said it "helped a bit". It always feels dry even after removing the cable from the sheath and lubing it completely.

Anyone else have a magic formula? :?:

[krick3tt]

I use 3 in 1 oil...it's a very light oil that flows easily.