240 runs out of power under load, i.e. going up hills

[Don East]

Well I've gone completely through the fuel system including having the tank redone. No change. Tomorrow its dizzy time.

Don

[madkaw]

Don,

So are you running SU's ?

Have you or do you know how to set float levels?

You stated that the car feels like it is running out of gas- maybe it is! Float level is very important , and revving it up in the garage tells you nothing about loading float level.

[Don East]

I took the dizzy out and there was some rust on the thin metal plates also one ball bearing is missing. I've been trying to find a rebuilt or replacement. and the only think I can find is from Mallory. Does anyone have any other suggests?

Thanks Don

[Don East]

Another question: When I had this car and it was new, I was able to tune the car to a point when the tail pipe was gray inside. At this condition the car was tuned perfectly. For many years I have not been able to achieve this level of tune. I've begin to think that the gray came from the fact that I was running 100 octane gas. Remember it was available in 1972. Anyone have thoughts on this idea?

Thanks Don

[Wade Nelson]

What is a dizzy?

Either a distributor or a blonde date you KNOW you're going to get lucky with.

[Wade Nelson]

Lack of power is often due to problems breathing. Restricted air intake or plugged exhaust.

Put a vacuum gauge on it and see what's going on.

http://www.secondchancegarage.com/public/186.cfm

[madkaw]

Pertronix on your dizzy or an e12 80 from a zx . I would recommend the zx dizzy and don't look back. Search it and you will find all the info

[EScanlon]

Check with the dealer, some of these parts are still available from them.

I'll check for the part number later so you can call them with it, but maybe someone will beat me to it.

Additionally, the ZX dizzy is a simple swap system and those CAN be obtained through auto parts stores. You want the 79 280 ZX with the E12-80 module.

E

[Don East]

Thanks Wade, I needed that!

Don

[altabow]

I've been through very similar problems that you describe. I felt foolish for making the situation more complex than it was. The car was fine on flat roads but climbing a big hill and accelerating hard would show the power loss right away. I ASSUMED that it had to be something out of the ordinary. I was wrong. It simply needed a fresh fuel filter.

[Don East]

I've been through very similar problems that you describe. I felt foolish for making the situation more complex than it was. The car was fine on flat roads but climbing a big hill and accelerating hard would show the power loss right away. I ASSUMED that it had to be something out of the ordinary. I was wrong. It simply needed a fresh fuel filter.

Altabow, thanks for the input. I started out with the same idea. I have changed filters, cleaned all of the gas lines and even had the tank reconditioned. I'm now working on the dizzy approach to the problem. The thin gun metal metal plates in the dizzy were rusted and the shaft on the updated dizzy had begun to sizes up. Finding a replacement has been a bit of a challenge. I have found an original single point dizzy for my car and I'm looking for rebuild with electronic interior parts. If anyone has suggestions I'm open for ideas.

Thanks Don

[Captain_Zeros]

I had a very similar problem on my car, my 73 has an electric fuel pump by the tank and a brand new mechanical pump on the engine. The car would run fine up to about 50 mph, rev in neutral, etc, but if I tried to cruise at freeway speed or go up a steep hill it'd bog and die. I monkeyed with the distributor for weeks to no avail. The electric fuel pump's wiring was out of whack and it wasn't running and the disabled electric pump in the way was just enough of a restriction to flow that it caused cavitation and basically vapor lock as soon as the nose went much higher than the tail-end of the car, it's gotta suck the fuel against gravity. I disconnected the electric pump and ran a fuel line straight from the tank to the body hardline (to the mechanical pump) and no more problem.

A help in that diagnosis was throwing an inexpensive fuel pressure gauge on by the carbs, with the non-functional electric pump in place my fuel pressure was low-ish and fluctuated quite a lot between around 2 and 3.5 psi at 1000 rpm, but with it removed from the equation my fuel pressure was rock solid around 4 psi which is right where it ought to be.

Also, when it comes to the electronic distributor, I have one out of a 280zx and it had the same smashed plastic ball bearing carrier that is oh so common with those, I sourced a pair of sintered bronze oil impregnated bushings and replaced the whole ball-bearing assembly with bushings. Vac pulls it just fine as far as I can tell. I took the unit off my car though because the vacuum advance curve wasn't to my liking and I was trying to revert all the changes I made to my car trying to hunt down the aforementioned problem caused by a nonfunctional fuel pump.

Edited October 26, 2012 by Captain_Zeros