1972 Float Adjustment ...

[psdenno]

In all the years, did.the Z ever run smoothly and with adequate power?  Not sure if that was ever mentioned or if it's had this problem the whole time since it got off the boat.

[siteunseen]

In my best one eyed Peter Falk voice, "Yes Sir I see where that could be a problem!"

[jalexquijano]

17 hours ago, Mark Maras said:

  Who knows? At this point in time, all I know is, he's got an engine with supposedly good compression, rebuilt carbs from ZTherapy and it's never run worth a damn. It should be easy to eliminate the carbs from the running crappy scenario and move on to the next problem. Hopefully the running crappy will be in the past and the fuel and engine overheating issue can be looked at. I can't believe that Panama heat is the sole problem either. There are Z's running in Arizona and other hot areas that have beat the overheating problem.

I must confess, I've have had kind of an uneasy feeling that Jalex would be better off with a stock engine due to the driving conditions in Panama. Used engines are still cheap and only take a few hours to install. That said, I'm not ready to tap out yet. We've got a way to go before a different engine is a possibility. Let's get back to the carbs and floats and cross those off the list.

I havent done a new compression test since 2 years ago. I do have noticed that if i pull the spark plug cable terminals out from each of the spark plugs when the engine is at idle there is an idle drop. The only one that does not affect the idle is spark plug number 4. Is this normal?

[Mark Maras]

 No, unfortunately it's not normal.All cylinders should act the same if all things are equal.  It may be a good idea to take another compression test. I would suggest readjusting the valves first. Have you ever done a compression test or adjusted the valves yourself? If not, do you want to try or take it to a mechanic. Neither task is terribly difficult. The compression test is very easy. Adjusting the valves is a bit more involved but not difficult.

[jalexquijano]

45 minutes ago, Mark Maras said:

 No, unfortunately it's not normal.All cylinders should act the same if all things are equal.  It may be a good idea to take another compression test. I would suggest readjusting the valves first. Have you ever done a compression test or adjusted the valves yourself? If not, do you want to try or take it to a mechanic. Neither task is terribly difficult. The compression test is very easy. Adjusting the valves is a bit more involved but not difficult.

Valves were adjusted a couple of years ago by a mechanic as per schneider spec sheet attached yesterday.

[Mark Maras]

 It's time to do it again. The problem with #4 cylinder could be low compression caused by a valve not closing all the way. Proper valve adjustment is one of the things that MUST be done before fine tuning the carbs.

[jalexquijano]

9 hours ago, Mark Maras said:

 It's time to do it again. The problem with #4 cylinder could be low compression caused by a valve not closing all the way. Proper valve adjustment is one of the things that MUST be done before fine tuning the carbs.

Okay. Took the car for a drive at 3.5 turns clockwise. No fuel starvation whatsoever. Good response. Rpm set at 1200 at idle maybe i should lower it to 1100rpm. I have attached pics of plugs 2, 5 and 4 for your opinion on the mixture. Should i lower it to 3?

[siteunseen]

You are confusing us, me for sure.

Turn them all the way up towards the passenger's fender then

2.5 turns down towards the driver's fender.

[Mark Maras]

Jalex. Glad to hear things are improving. Did you check the fuel level in the nozzles? The float level may be getting close. Is close good enough for you? Not for me when all it takes the removal of six screws to check both carbs but it's your call. If you're satisfied with the float level for now, go ahead and start adjusting the mixture screws. You're going to have to adjust the valves and possibly do a compression test when you're ready to address the problem in #4.

 Cliff, I've figured it out. Jalex's point of reference is from the top view. Visualizing the screw from that vantage point, the screw does turn clockwise to drop the nozzle. It really doesn't matter to me as long as we're all on the same page.

[siteunseen]

Yes good news from Jalex.

You say #4 is not interfering with the way it idles.

When you disable the rear carb will it continue to idle, very rough but still running?  If #4 is dead I don't think it possible to run on two cylinders, #5 & #6 and those are the three that run off the rear carb.

I'd swap that plug around and see if it's a bad plug or a dead wire.

They run good with fuel don't they. 

[jalexquijano]

At least you understand me and have patience. 

[Stanley]

I was going to post "righty-tighty, lefty-loosey" thinking that it might help. But after a little more thought, I guess that's only correct half the time. Visualizing a clock face, when tightening a fastener, you're turning the wrench to the right from 9 o'clock to 3 o'clock. Then you turn the wrench to the left from 3 o'clock to 9 o'clock. Refried confusion is making itself clear.

But the factory service manual, chilton, etc., will all say turn the mix nuts counterclockwise to richen the mix. They don't mean looking down from the top, since the mix nuts are on the bottom of the carb and screw in like any normal threaded fastener. They mean looking up from underneath. If you tune by the FSM etc. and make that mistake it will be impossible to set the mix.

Seems extremely simple, but I've done it wrong too.