Engine runs only when choked...

[240Zdragon72]

I have to choke the carbs in order to get the engine to run. After letting the choke off, 10 sec. later, the engine will sputter then die. What is causing this? Could the carbs be durty? I haven't touched anything on the carbs when doing the engine swap. I am very upset. :tapemouth

[seerex]

check to be sure that the choke is releasing fully , sounds like they might be sticking

[Daniel]

Have you run the engine to "normal temp"? When mines been down for awhile its Grumpy. You may have an air leak on the intake .What was the Swap you did?

[240Zdragon72]

Daniel, I took the engine out of "Orange '72" and put it in "Jennie '73." (untill I can get the Turbo engine fixed) I did have to pull the intake and exhaust manifolds off, though. It seems like the engine is getting little to no gas. The electric fuel pump I installed today works and feeds the clear fuel filter in the engine bay. (so I know it is getting fuel.) Should I clean them anyway? It has only been 15 months scence the last time I cleaned them.

What do you think?

Edit: I should also mention that there is a little box on the passenger side of the fire wall, next to where the choke cables come out, that was smoking. What was this and could it be part of my problem (I don't think so, but it is worth knowing what it was)?

Thanks

[Daniel]

So you changed motors that the carbs were on without resyncing them?

[240Zdragon72]

No, same motor, different car. I don't understand it.

[Ed]

Edit: I should also mention that there is a little box on the passenger side of the fire wall, next to where the choke cables come out, that was smoking. What was this and could it be part of my problem (I don't think so, but it is worth knowing what it was)?

Thanks

This little box is called a "Throttle control relay" it came only on the 73's and from what I understand it controls the throttle emission stuff that is on the balance tube of a 73. It keeps the throttle open until the engine warms up. If you have removed the emmision stuff from your 73 balance tube then that relay does nothing (besides smoke, ).

[Gav240z]

Sounds to me you need to readjust your carbs. if anything when changes things like this over often they will need readjusting.

[Zs-ondabrain]

This one is way out there, but my 70' would also only run or stay running at a crappy idle if I had the choke on.

It turns out that I had real crappy spark and with the choke dumping more fuel into the chamber, it had a chance to keep running. sounds weird but the solution to my problem was the E12-80/D6K8 distributor swap ( from points to electronic)

Now that there is decent spark and the throttle has been re-adjusted properly, It idles like a dream (a stage 2 cam, header, rumbling, blub blub blub blub dream) but none the less, very smooth.

Not every Z is alike but what the hell, It could'nt hurt to check.

Dave.

[240Zdragon72]

I have the E12-80 modual on the distributor and it is hooked up right. As for the smoking box, it will no longer be there in the morning. I will try to change the spark plugs to the Bosch ones I have from the parts motor. They still look in good shape. I will also buy a new intake/exhaust manifold gasket for good measure.

Thanks everyone.

[Zs-ondabrain]

For your sanity and mine (ours), stick with the NGK's. They are the Supierior plug when it comes to the L-series. I've had nothing but dissapointment with all other plugs. With the exception of the 4-bridge rotory engine plug with the (MSD 6A) as a back-up.

Then again I could be babling :stupid:

Let us know how you end up fixing it,

Dave.

[240Zdragon72]

Hey, Zs-ondabrain, I took your advice and got some NGK plugs #BPR6ES, new intake/exhaust, carb, and exhaust manifold to pipe gaskets. I will have to put them all on in the morning (have to work the midshift :tapemouth ), hopefully I can isolate the problem soon. I tossed the Bosch plugs. By the way, how do you sync the carbs? I've never had to do it before.

Thanks