New Member

[jimvidmar]

Hello Everyone,

I just joined the Classic Zcar Club as a member. I have looked at this site in the past, but decided it would be best to become a member.

I have a '72 240Z that I have owned for maybe 10 years. I bought the car from a local owner (Cleveland, Ohio area) who bought it from Arizona. It was redone in about 1986 from what I can tell (a photo album came with the car). It is a solid car with some rust in the panels in front of the rear wheels, which I intend to replace over this winter.

The car is slightly modified for performance. It has the 240Z motor and 4 speed, but now runs with an N42 head and Motorsport 2-into-1 headers. It has Koni adjustable shocks and 15" aluminum wheels. I think it's pretty nice. I have always enjoyed the car, although I wish it had a bit more power so I could put down most of the newer sports cars that seem so abundant these days. (But I will race with any of those cars on curvy roads!)

I work on my car myself for the most part and have done some things like fix broken header bolts with helicoils, replaced headers, replaced master / slave clutch parts, etc.

The PROBLEM I hope to find help with on this site is that last night I took a ride and something went wrong that perplexes me.

I ran the car through an up-and-down winding road nearby where I live and pushed it pretty hard. At one point I missed a shift and the engine revved up toward redline (I think). When I finished my run, I slowed down but noticed that the engine was racing when I put the clutch in.

The engine was racing at about 3000 rpm with the clutch in. It would not idle down from about 3000 to 3500 rpm!

I nursed the car home (about 5-6 miles) by driving in 3rd and 2nd and rolling through stop signs on side streets to keep the rpms down. I shut the engine off and had to stall it finally because it wanted to keep on running with the ignition off, which was understandable under the circumstances.

So now I need to figure out what went wrong. The throttle linkage seems OK, the gas pedal seems OK, everything seems OK... but if I start the engine it races right up to 3000 and wants to go higher.

Any ideas on where to start figuring this out would be appreciated.

Is it possible the needle valve(s) are stuck open or something like that?

Hmmmm.

Thanks in advance.

Nice to be a part of this forum. Hope I can help someone along the way.

Best regards.

Jim

P.S. I will post the tech details and picture of my car as soon as I can.

[sblake01]

Possibly a piston in one of the carbs is stuck. That happened to me once in a Datsun 1600 Roadster I once owned.

[RolfSis]

I am a total novice, and no experience with your year car, and only learning about the '71 240Z. That said, found this article interesting and curious if it might not be of some help to you.

http://zhome.com/ZCMnL/tech/cooper.htm

Asta

[jimvidmar]

Thanks for the feedback, Stephen. I will take a look at the carbs. I was wondering if one or both of the carbs was stuck open.

Also appreciate the tech article from RolfSis.

Lots to learn.

Jim