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my 240 is very very sick......:(


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NEED HELP!!!

Took the '72 for it's first test drive on the open road the other day (finally got her to stay running), and let me tell you, it was some scary $^!#. Here's what I noticed in 6 miles of slow, slow, cautious/aggravating driving:

- The 3-sp automatic shifts hard and somewhat sparatic

- At about 30mph the car loses all power and takes its time getting past 30

- It bogs horribly on hills...to the point of stopping/stalling

- The carbs have an irritating tendency to load up and backfire "clap" another sign of running rich

- Of course exhaust fumes everywhere

- The water temp gauge apparently isn't hooked up

- Even scarier, the oil pressure gauge STAYED at 90+lb once I got her going

- And she's missing like mad while idle and/or load

- Other than that, steering was fine, brakes had a lil squeal, all the lights worked (tho the int. ones were weak and dim), and I didn't die from stalling out on the hill w/ a dualie behind me.

Ok my request is for some info I know some of you guys are teeming with...I already know adjusting the SU's to correct specs and tuning ignition timing will cure some of these problems...maybe upgrading to an electronic dizzy will fix the chronically rich issue but what about the shifting and dangerous oil pressure? Is it a fluid issue or sensor/pump? Any insight would be appreciated, this car has to be in top shape b4 August (college ride) and I have limited funds to fix her (otherwise I'd say 'here mechanic, cure all her ills") thanks in advance, peace

UPDATE: Yeah I fotgot to mention, I do have round tops (thank god) Rest of specs are '72 Series II, 3-spd auto (dammit) and probably all bone stock mechanically

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Hi Mak,

A carburettor backfire is lean, not rich.

The auto possibly needs a service. But first, is the vacuum modulator hooked up?

Check your cam & distributor timing - ask for details on how to this if you don't know/can't find out.

I expect that the oil guage isn't hooked up either - does it read max with the ignition on, but the engine off?

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I don't see how it's lean considering all 6 plugs were fouled in record time/ reek of gas ect....I'll have to get back to you on the vac. mod.

As for the oil gauge it idles in the dead middle but slides to 90 when accelerating or running at any speed over 20-25 period.

Feels like I have a geo metro 3-banger pulling the Z instead of the 6...total lack of power plus the above mentioned problems

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or thought you said was you had backfiring out of yoru carb, which would mean it is running lean.

make sure to check all your adjustments before going on and running the car again.

i would gap the plugs at at least .40, set your timing properly if you have a timing gun, get your carbs set properly or at least at a good base line.(you do have round top carbs im hoping)

also make sure that your ignition system is up and running properly. are you points gappd properly?, new cap, rotor button? new wires? coil in good condition?

on the tranny make sure that it is full of fluid and that its not dirty or brown looking or smells burnt. if your not sure of the last time it was serviced this may be in order. new filter and fluid.

one other thing i can think of is your fuel system, did you replace all filters and inspect the carbs as well for any signs of rust getting into anything.

good luck and i hope you get her running better

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I susspect the sender does not match the gauge. I took a sender from a 280 and installed it on my 240 and it read over 90 psi while revving and about half way during idle.

I bought a new sender from MSA. They sell the early R-1600 (roadster) sender for the 240. It's more accurate and lasts longer. But you've got to replace the "bullet" style connector with an "eyelet" style.

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hey man

ur car sounds how mine was around 18 months ago.. hehe

but now its all perfect

this is what i did

new plugs + wires

make sure your timing is good, around 12degrees, or something round there... - if you can't get any timing marks with a timing gun, get a new distrubuter imediatly, a electronic one with the module E12-80 will work no problems, just need to same mount as from the car your getting it from etc...

I changed my fuel pump, was very harsh, was running like 0.5psi and its supposed to run something like 4psi

for your carbs, hoping round tops.. take them off, take them apart, get some carb cleaner in the can, thats presurized, take ur carbs apart and spray the $^!# thou them with the card cleaner, i used 1 can on each card they were that bad, after that put them back together, making sure the needles are seated correctly, and the float levels are all set nice and sweet, so it does't overflow the bowl.. and not so hardly any fuel goes in there...

Alsooo, change your filters, fuel filter/ air filter etc...

with ur carbs, get a uni-flow meter, so its easy to adjust the air-flow, and also put new oil in your carbs, i usually put in automatic transmission fluid, but i often use this other stuff, that my dad gave me, not exactly sure what its called..

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Originally posted by Victor Laury

I bought a new sender from MSA. They sell the early R-1600 (roadster) sender for the 240. It's more accurate and lasts longer. But you've got to replace the "bullet" style connector with an "eyelet" style.

I'm not so sure that this one is "more accurate", as when I installed one in my 72 240Z, now; with the ignition turned on for one minute with the engine NOT RUNNING, the guage will read about 20 lbs oil pressure. When the engine is running it reads about mid point in the pressure range (appx. 60 psi). No way is there ANY oil pressure with the engine not running, but that guage seems to think that there is pressure! :stupid:

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As far as the oil pressure is concerned , get a nissan sender they work and are as accerate as these things can be. To really tell what the pressure is you need a mechanical gague, but the correct sender will tell you where you are. On the rich running , If you are at all aquainted with the SUs be sure the choke cables are adjusted so when t he lever is all the way forward the adjustment "knobs" for the mixture is all the way up. check the little hoses at the bottom of the carbs if they are stiff replace them as they will cause the choke adjustment to stick in a lower position and will dump fuel into the engine. If all of this stuff is ok and you still have the problen . Turn the mixture adjusters counter clock wise to the stop and back down , clock wise, 21/4 turns . that should get you close on the mixture . You MUST buy a uni-sun to ballance the air of the carbs . That is a must. Those fuel lines are small and the fuel lines at the parts store are too large and to stiff. DO NOT USE VACUME HOSE ! Z therapy has the hose. and you can try Nissan. Another place is a cycle shop. They may have a uni-sun also. I bought mine a the local parts store speed parts section. $25.00

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