Complete starvation when cold

[IdahoKidd]

I've read posts until my eyes are burning searching for some sort of answer.

1972 240 3 screw SU's. Car hadn't been driven since 1992 (43K original miles). Cleaned the tank, new filter, flushed the lines, etc. When it is cold (not started) it will crank for an eternity and never fire. Nothing. Spray a little starting fluid into both carbs on the crank cycle it fires and does the lean pop thing. Do this several times and it will pick up slowly and then run along if you hold it above idle. Once it warms up, it runs very well, idles well, drives well and restarts well. But, once it goes cold again, no way to start it without starting fluid and coaxing it along. Once it is started, pulling the choke lever back raises the idle speed and it runs rich. Take the choke off, it works just fine. So, I am guessing the choke is working. (The levers move on the outside of the carb).

I know the carbs need a thorough cleaning and when my Obama bucks get here I will have Z therapy work them over. On the other hand, once it is warm there are no starting or diveability issues at all so they can't be all that bad. I am over looking something really simple with the fuel delivery somehow. Any suggestions?

Thanks,

Leonard

[kenz240z]

You mention that pulling the choke lever raises the idle speed, but have you verified that the fuel nozzles are also moving down when the choke lever is pulled? When the choke lever is pulled it does two things: pulls the fuel nozzles down about 1/4 inch for a richer mixture and also cracks the throttle valve.

My guess (from here at the computer in Berthoud, CO) is the fuel nozzles are stuck and not being pulled down with the choke applied. When the engine is warm, pulling the choke, even with stuck fuel nozzles, would raise the idle due to cracking the throttle open - just like stepping on the foot feed a little bit. So this is no proof that the choke is working properly. Take another look and let us know what you find.

[IdahoKidd]

I'm headed out to the garage a little later. I have read several posts about the nozzles moving but nothing about how to tell. Is it a visual thing while on the car, can I tell with a finger inserted? I do remember somewhere on a shelf (aka absolutely no idea where) I have another set of carbs. If I can find them I might have a better look.

As a foot note, never loan your manuals to a buddy............ "dude, I don't know where I put them........."

[Bruce Palmer]

Very easy to tell if the nozzles are dropping. Have someone pull the choke lever and feel under the carbs to determine (I was going to say "see") if they come down and return to the up position when the lever is off.

You can also remove the screw from the linkage to the nozzle and see if those bad boys move up and down easily. That would also facilitate taking them out and cleaning them and the tube they ride in of any old gas varnish that may be restricting their movement.....

[IdahoKidd]

Follow up:

It turns out both nozels were stuck so firmly I had no idea they were to be a moving part. 2nd set of carbs were exactly the same, but third set had one side that moved freely and that "turned the lights on". Cleaned them up, cleaned the float bowls and the pistons, put it all back together and cranked and cranked and cranked. Turns out the hot wire to the coil had gotten knocked off when removing the air cleaner. Ugh!

So now it did start but has that lean pop on acceleration. I have seafoam in the tank and in the carbs so will let it all cycle through before I get real excited. I also don't think I have the correct amount of oil in the carbs, it certainly didn't take much. The choke works like it should ( I think) and definately different than it did.

Thanks Bruce and Kenny!

Bruce, I'll be in contact shortly about a couple sets of SU's and a video.

Edited December 6, 2010 by IdahoKidd
spelling-the bowls really did look like bowels when I took it apart

[Bruce Palmer]

Leonard,

Trade ya two sets of carbs for that 444. A friend here has a volvo Duet panel he wants to trick out for a wine delivery rig for his winery. It has that front end and a two door wagon body. Cuter'n a bug.....

Let me know when you are ready to go.....

Run those nozzles down a half turn and see if that lean pop gets better. If not try another half turn. Of course with stock Z needles they may just run like crap with all the other potential issues the carbs may have.....

[IdahoKidd]

Bruce,

Probably won't part with the Volvo. I'm tickled someone else out there even knows what a duet is! I'll attach a couple of pics of the 3 car Volvo club we have. The Z car club here in town has 3 members but at least there are 6 cars. Notice the plate on my 57, it is the only plate in the US that has that. When I got it, I didn't have a clue that Viagra was a little blue pill, I just knew driving this car always gave me a woody.

As for my carbs; the ones on the car in question have a large star wheel assembly and a spring between it and the bottom of the carb (my other sets have a knurled knob and no visible spring). This was seized as well and I ended up finally getting it to back out when I cleaned them. The nozzle was so stuck in the carb that I actually pulled if out of the base it was pressed into. I guess I didn't fully understand how it worked when it was back together but am guessing it sets the richness in the run position. (I really need to go get my manual back......). I'll fool with it a little more today. I assume just adjust it to its best running position until I get my manuals? The temp is up to 30 today so it is much nicer to work on things than it has been.

Edited December 6, 2010 by IdahoKidd
spelling and photo

[Bruce Palmer]

Oh, that teardrop trailer doesn't add anything to the "cute" factor either.

On your info needs for the carbs, our JUST SUs dvd should be a big help. We hear from lots of guys that they prefer the dvd over manuals because it avtually shows whats going on. Just a thought.....