THE PORTAL HUB - Pinzgauers, Haflingers, Volvo 303s and more!

I changed my valve cover gaskets this weekend, and while I had everything apart I used the synchronizer on the carbs. I have the BK STE unit, you can Google it to get more information and prices. The linkage is connected because I was already done when the pictures were taken.
The carbs weren't far off initially, and it idled better afterward. I have no hesitation whatsoever on acceleration, which was something that always bothered me before the new ignition system was installed and the carbs were synchronized. Anyone can do this, it isn't rocket science!
I have the Zenith carbs with the big idle mixture screws, and discovered the sweet spot is exactly one turn out. I set all 4 like this and it doesn't vibrate, very smooth. I wish I had a gas analyzer to tell me how close the setting really is to optimum.
I painted the carbs with Eastwood carburetor paint, but am going to try yellow chromate on another pair of carbs to see how well it works. I'm thinking the finish would be more like the factory finish with that.
https://plus.google.com/u/0/photos/1082 ... 3688794480

Nice work. Glad you are pleased with the outcome.

Carbs look good in the pictures
The chromate would be a lot harder as you would need to take everything apart and prep for dip
But if already apart then will be neat to see difference!

Can't wait to install my SSI too.

10 kg/h is to high idle you need to be about 8 kg/h if the carb is set properly

How do you lower it to 8? Reduce the idle speed or change the mixture? Or both? I'm not an expert by any means with carbs, but I don't mind attempting to learn.

you idle it down and best seating is 7.5-8

I can do that, but the idle speed will be too slow. Recommended idle is around 800, I can't get vacuum that low at that RPM. Balancing is easy, but it's up around 13 or so to maintain correct RPM. Opinions??

Per repair manual, set idle between 850-950 rpm warm, 800 is too low

I can't resist tinkering with the Pinzgauer, even when it is running good. It's just too much fun. Can anyone else relate?

oh I can relate! Especially when, despite the engine running very well, I don't get the combination of settings the manual and knowledgeable mechanics say you should have. Drives me nuts as I ask myself - why? What am I missing (probably a lot given my troubleshooting experience). My carbs are currently synched at 4.5. That's right, 4.5. Idle screws are turned all the way out to the point where they do not touch the plate they are supposed to touch. Mixture screws are at 1.5 turns out. RPM is low 910s-900. The only way to lower the RPMs that little bit more is to lean out the mixture. When I do that, the carb synch setting goes even lower. If I increase the idle or increase the mixture to increase the carb synch setting, the idle RPM is way too high. So I've left it as is not knowing what else to check/do yet it runs well. FYI - I have the SSI and have replaced to the 2 big gaskets in each carb (the one on the engine mount and the middle one). Plugs are relatively new (less than 1k miles). Fuel filter is new.

Harry,
I think if mine were running as well as yours seems to be, I would be quite content.

I have been curious for some time about carb syncing...if they are both equal and your idle is smooth and the RPM is 900 plus or minus a few, why is not that a good thing?

Having to attempt settings per the manual, and we are dealing with a 40 plus year old machine with some wear on it, how can one be expected to have the expectation of settings for a new vehicle?

I have read and heard various opinions for carb settings and the most reasonable seemed to be about 6 to 9 for a balance, and I try to achieve that as best as I can. If I get them the same I am content that I have done a fair job.

My biggest reason to keep the thing running well and not having things fall off is that I don't want to be that guy holding up everyone on the trail. Mostly I spend time with Jeep, LR and Toyota folks as I am the only one with a pinz in virtually any group or club I am in. We (pinz owners) are so few, as a rule, and there is a lot of..." What the hell is that?" Got to keep up the performance and the idea that just cause it is not a fancy new thing with tons of bells and whistles it is still viable for ownership. Mostly I really don't care much about the newer vehicles and I would rather have the pinz anytime.

Happy trails

edit: what Edzz says and besides the tool is plastic (see below)

There seems to be an assumption that all carburetor sync tools are well calibrated. I have found it more reasonable to use the sync tools to compare flow and take the number shown on the gauge with a grain of salt as I have no means to check the gauges calibration.

YMMV

Throttle plates/shafts/worn bases, or vac leak under the engine tin.

Carburetor - Synchronizer adapter

I bought a Weber Dellorto Mikuni SU EMPI Carburetor Synchronizer from eurocarpartsguy on evil-bay and I mistakenly ordered the SK instead of the larger BK model. I contacted the seller about an exchange. After 2 weeks I have not heard from him so I decided to make an adapter. I found out that a piece of 2" sch 40 plastic pipe fits snugly in the carburetor bore. The pipe ID fits the meter cone with a good seal so for a few cents worth of plastic pipe and a few minutes on the lathe I'm in business.

Once I tightened up the numerous loose fasteners on the rear carburetor I was able to set the idle at around 950 (VDO tach) with mass flow at 8.5 on both devices. I did not adjust the valves or re-time the engine. That will be the next iteration and then i will rebuild the carburetors and do it all again. My approach is backwards I know but that is not unusual for me.