New Zealand Datsun Club

Hi guys I'm new to this forum. Joined up to try get help about an issue I'm having with my 1995 Nissan datsun ute. It has an NA16 motor which I can't seem to find info for anywhere!

Anyways I bought it to take my dirt bike around and I've always wanted a ute. I love it though! Just need to know how to fix the issue I have so here goes:

My ute from day 1 has idled really high when cold. When it has warmed up, it struggles to idle!

The choke butterfly is partially open all the time from cold. Sits like this

When it sits like that, the ute idles high and is warming up.

I managed to simulate what happens when it's warm:
If I move the choke all the way to fully open with my finger, or putting my hand under the carby and using the lever, the engine still runs fine for a few seconds and then starts struggling to idle. Same way it does when I'm driving and come to a stop after the engine is warm. If I let go of the choke it'll pop back into place and everything is fine.

HOWEVER,
*If I hold the choke where it is
*then hold a bit of throttle
*then while holding throttle I let go of the choke and then let go of the throttle, the choke sticks in place at fully open and as I let go of the throttle the engine will struggle to idle.
If I give a good jerk on the throttle, the choke pops back into the partially shut position and the engine comes back up to idling high again.

So it appears when the choke is open as it should be when the engine is warm, the motor struggles to idle.

What's going on?

Thank you in advance and I hope to start a project thread as I tidy her up!

Get it warm and adjust the idle speed screw, it may just be set too low, it works totally separate from the high idle system on the choke. It will be near the base, and adjust the throttle shaft open.
Let us know how you get on, and post up a photo of your engine.

classicdat wrote:Get it warm and adjust the idle speed screw, it may just be set too low, it works totally separate from the high idle system on the choke. It will be near the base, and adjust the throttle shaft open.
Let us know how you get on, and post up a photo of your engine.

Thanks for the quick reply!

Is the idle speed screw the one I can see just under the carb from the drivers side fender? Idle goes up as I turn the screw in? If I do that, the idle is really high when the engine is cold though... There's also another screw below it that has a green spring, that's not the idle screw right?

Oh also just near that idle speed screw there is a little electrical plug. The top pin is horizontal, bottom pin is vertical. When I got the ute, the plug connected to hit was all melted. I cleaned up the connections and hooked it back up but it keeps sparking and even smokes. So I unplugged it and isolated it. Hasn't changed anything about how the motor behaves though.

I'll post up a pic of the engine tomorrow hopefully

Well here's some pics of the engine and also that plug I was talking about: http://imgur.com/a/Ps57z#0" onclick="window.open(this.href);return false;
Check out how tidy the interior is! Wish the exterior was the same but it's had a tough life. Many dents!

I seem to have sorted the idling issue by getting the engine warm and then turning the idle screw inwards. I dicked around with the idle mixture but it did nothing unless I turned it all the way in, the idle would increase. But I turned it back out to what it was again as everything seemed fine originally.

Haven't driven it yet. Will see how it goes.