Mark Maras

You're right, Fred was cool.

Excellent. The coughing you're describing is a too rich mixture caused by too much choke. You've figured out that the choke can and should be adjusted to suit the conditions, ambient and engine temperatures. While I'm thinking about it, should you ever want to see if the fuel mixture is too lean (when the engine is warmed up) gradually pull the choke while you're SLOWLY accelerating. If you feel the power increase the mixture needs to be a bit richer. Drive it for a few days or until a new question arises. Oh yeah, have you driven by your old mechanic's shop yet?

There are a few things that would cause dark plugs at 2 1/2 turns. Nozzle?s are sticking in the down (choke on) position. You can manually push up the nozzles with the choke off to see if they're sticking. They should be all the way up with the choke off. Choke cable?s mis-adjusted and not allowing the nozzles?s to go all the up. Readjust choke cable clamps at carbs. Float?s adjusted too high. Easy way to tell is remove the tops and pistons. With the choke off, there should be no fuel above the small hole in the nozzle that the needle fits into. The fuel level should be below the hole. I've also seen nozzles stick down because of the little flat bar linkage that attaches to the nozzle on the bottom. If both mating surface on the ends of the linkage aren't exactly parallel to the other mating surfaces, the linkage will bind. It's easy to fix with a slight twist after careful scrutiny.

Earth to Cliff. Earth to Cliff. Come in please.

@jalexquijano "choke on for 10 to 12 mins", did you leave it pulled all the way on until the engine was warmed up (presumably temp at half) or did you gradually push the choke forward as the engine warmed?

@7tooZWell said. @jalexquijano You can get a "feel" for the choke location during warm-up (while driving) by gradually easing the choke off while you're GRADUALLY accelerating. As you slowly push the choke knob forward, you'll feel the engine lose power, at that point give it a little more choke and you'll feel the power increase. Too much choke when the engine is warm will make the engine run a little rough with a decrease in power and could increase the possibility of backfire from the exhaust due to the rich fuel-air mixture. Yes, do all street tests with the air filter installed.

Tribbles are green in the Pacific Northwest.

Hmmm, I think you may be on to something there. 160` is kinda low. @jalexquijano Is it still overheating in traffic?

I just figured he wanted to keep it original, grey and wrinkly.

I don't blame Jalex for pushing it. EXCEPT WHEN THE ENGINE IS STILL COLD. One has to push "IT" (submit your own definition) every now and then to see if it's worth keeping. Who want's to baby something forever. Especially a Z or a girl.

A full tank of gas or just accelerating?

My favorite line. Captain, I'm attempting to build a pneumonic memory circuit using little more than stone knives and axes. I've felt that same way on many projects.

Cara Mia, Querida, Querida Mia, Tish, Cara Bella and Bubala, Mon Cherie, Querido

If anyone wants to know more about welding hazards, Google "Fume Fever". Been there, done that.

@siteunseen Possibly, but I've seen crappy, worn out engines run strong. I'm still going on the assumption that the engine is good. The compression is good, the valve train isn't shedding parts, even at six grand. If we get the spark and fuel right, I think it'll be good to go. At least I'm hoping so.

@jalexquijano Looking good. Let's assume that the mixture screws are close for now. Am I correct that the gremlin we're working on is the sputtering before it's warmed up? Next time you're out and the engine is warming up and sputtering, note the temp on your gauge and push the choke knob slowly forward. I'm trying to figure out if the sputtering WHEN COLD is caused by a rich or lean condition. If the sputtering improves when you pull the choke it means the the mixture is lean. If you push the choke forward and the sputtering improves the mixture is too rich. Please note, I'm not talking about adjusting the mixture screws at this point. I'm trying to get a feeling as to what the engine wants when it's cold. This problem could be just choke related. Not being in Panama and being able to drive your Z, I'm guessing that the sputtering is caused by too much choke. Too little choke on a cold engine will cause it to fall on it's face when a load is added. I'm betting that the sputtering will improve with a little less choke. Try it. Remember tho, it's not good for your engine to be pushing it HARD when it's not fully warmed up.

"Tish, you spoke French!

@siteunseen The fact that the engine seems to run fine when it's warmed up makes me think that the chokes are fully closing. I'm sure we're not done but the only problem I see at this time is the engine runs a bit crappy if it's pushed when it's cold. Which is totally understandable. I'm the same way.

So many good ones. "I Mudd" was another memorable one. Harcourt Fenton Mudd, Norman, and the Stella's.

Thanks. One of my favorite episodes. Don't know why I wrote Vulcan. Chalk it up to "brain fade".

@jalexquijano Are you operating the choke in either full on or full off mode? Or are gradually easing the choke off as the engine warms? Either way, I'm not surprised that the engine didn't run optimally until it was fully warmed up. In the future, let's concentrate on symptoms that occur when the engine is fully warmed up. Any complaints when it's warm. Idling for a few minutes? # 4 plug looked the same as the others. We're making progress. @siteunseen Tick tock, tick tock.

With the threat of the tribbles multiplying and filling the Enterprise, Scotty beamed them to the Klingon mother ship. Who knew?

Thanks for the pics. Those plugs look very good. Was the engine fully warmed up when you started on the test run at what rpm did it start to misfire?

@jalexquijano Don't clean the plugs. Take a pic and post it. You could clean the plugs (after the pic) but if the mis-fire continues, you still won't know if it's caused by the plugs. Bite the bullet and buy new plugs.

@jalexquijano I've experienced lack of fuel in my Z. It had a partially blocked fuel filter at the time. There wasn't any cutting out, missing, spitting etc. It just wouldn't go any faster than 45 mph no matter what gear it was in. It would free rev to 6000 rpms but under power, in any gear, just 45 mph. The only time I've experienced high rpm misfire in mine, it turned out to be ignition related. I changed spark plugs and the misfire went away. Try installing a new set of plugs and see if it improves. I'd still like to see a pic of all six plugs.