Starting an OLD L24

[SmogSUX]

After assessing my funds at the moment, I've come to the grim realization that an RB motorswap is out of the question for me at this time. I think I can try and get the L24 running and do the swap later down the road when I have more money at hand.

I was reading through a black dragon auto booklet and noticed that the 70 and 71 240z had the L24 with 150 hp, whereas the 72+ started to go down in power with new emissions requirements and such.

I looked up and it said the early 280z with the L28 didn't have much more power than my L24 (I don't have the figure on me since I lost the magazine.) So it wouldn't be a worthwhile upgrade from my L24 for the time being.

 

Anyways...

My question is this:

If I'm going to try and get this L24 running that's been sitting since roughly 1986, what should I do?

 

I know for a fact I'm going to have to try and clean out the gas tank as it has to be filled with crap by now. And as an extra safeguard I saw someone recommended installing an additional fuel filter.

 

I figured I should change the plugs, oil, flush the coolant, but what else?

 

Should I not even try starting it up without taking the motor apart?

Do the carbs need to be cleaned out or adjusted? And input is greatly appreciated.

 

Thanks

-Nick

[Hrududu]

I've got similar plans to try and fire up an L28ET i've been considering buying. Its only been sitting about 4 years (or so I'm told) so not quite as long as yours. I made a list of things to take with me to the salvage yard to try and get it going.

 

1. 2 gallons of gasoline

 

2. 6 quarts of cheap oil

 

3. Car Battery

 

4. Sea Foam

 

5. Set of sparkplugs

 

6. Carburetor Cleaner

 

7. Work rags

 

8. Water for the radiator

 

9. Gloves

 

10. Tool box (screwdrivers, sockets, etc.)

 

Since I've never actually done this, I am sure there is plenty more that can be/should be taken along. Just thought I'd share my ideas.

[m4xwellmurd3r]

I think it really comes down to how well it was stored. go with all of Hrududu's advice. there really isn't much more you can do haha. I'd say just make sure you go over everything thoroughly and it'll be fine.

[Z24O]

the biggest hurdle is i doubt that the carbies will be functional,the fuel would have evaporated years ago and the seals/jets/diaphrams would have suffered....you may be able to try firing it up by spraying aerostart into the venturis while you turn the engine over...you may be lucky as the fuel is drawn through the carbies by the engine vacuum and they start running

the fuel pump(manual or electric)is also likely to be US or leak!!!....i would buy a cheap electric fuel pump and plumb it up with a temporary fuel tank(like a gallon can with a fitting for the fuel line),put some aligator clips on longer wiring that you can clip to the battery to power up the pump with adequate,clean fuel(taking sensible precautions to avoid endangering yourself with the petrol in the can igniting....check the system for leaks before trying the ignition)

the other thing i would do is pull all the spark plugs out(opportune time to put new ones in,correctly gapped)and spray WD40 or CRC(spray pack lubricants)into all the cylinders....leave it for 24 hours then repeat before trying to turn the engine over,manually if you can otherwise with the starter motor......then put the plugs in,check adequate oil and water and try firing it up

[madkaw]

Nick,

I just went thru this same scenerio with a 71 that hadn't been started since 88. I was doing this for a customer and I didn't promise anything. Fortunately, the prior owner to this guy thought enough to shoot some oil in the cylinders and turned it over every once in a while(so he said). The guy did drain the fuel out if the tank whih was great! I sprayed the cylinders as suggested and turned it over by hand first, then by starter, then eventually put fuel and fire to it. When I first started it I had 2 dead cylinders-valves stuck open slightly which causes the lash pads to turn sideways and not allow the valve to close all the way. Do a compression check when using starter to turn it over. If you have 0 on a cylinder that is probably what happened. Compression levels after starting were all over the place 90psi to 150 psi. Now that I have 30 minutes on the engine the compression levels are all up around 175, not bad for a old engine that sat around for 20 years. It smoked and still smokes a little, but seems to get better all the time, I need to get some highway miles on her. The original fuel pump still was good but the rubber diaphram was starting to dry rot. Have several fuel filters handy to replace after running the first couple of times. You will have to pull fuel tank and clean it or you will have a lot of problems. I had to replace filters AFTER cleaning the tank because the lines produce crap too! You might want to try some Marvel Mystery oil in the oil with your oil change to help break in the old motor.

By the way, the little 2.4 still has it, lot's of power, she still wants to go after all these years:razz:

[SmogSUX]

Hah, thanks for all the suggestions guys. I'll definitely for spray a ton of wd40 in the spark plug holes since I have plenty of that on hand. Then tomorrow with repeat and then manually crank the engine a bit.

 

Anyone use PB Buster for this? The can says it drives out moisture and acts as lube too, so I figured that would be good?

 

Also has anyone thought of putting a little bit of 2 stroke in the fuel for the initial startup? I use 2 stroke with my rx7 since I removed the stock combustion chamber lubrication system. (Long story...reliability mod ) Would the 2 stroke hurt anything on a piston engine?

[MatMan]

When I bought my car, it had been sitting for 12 years. If you are planning on driving this thing, you will need to consider replacing all the coolant hoses, soft, fuel lines, and soft brake lines. The carbs will have to both be either rebuilt or at LEAST refreshed/cleaned. As Madkaw stated, Marvel mystery oil is your friend. The choke line may be gummed up in the assembly. After the motor runs for a while, you may want to change the filter and oil AGAIN. Good luck!

[SmogSUX]

Damn....I'm thinking a l28 swap would be easier lol...$300 whole running 280z's pop up from time to time...

[Guest Henry]

My 77 z car was sitting for 15 years, Got the engine started with steps similar as listed, but my clutch oil was all gunked up. Clutch went right to the floor. Took me a weekend to get it flushed out correctly. Good luck.

[2savage]

Before an engine that has been laid up for so long is started it is essential to remove the head and observe the bores and valves. There is every chance that one or more valves were in the open position and if so, the cylinder will be exposed to moisture ingress and could have rust on the bore. Further, the valve itself may have rust on the stem that could cause it to stick. Either one of these scenarios will result in your engine grenading when you start it.

[ihatejoefitz]

If you've got power to the car and it still wont turn over, remember to try tapping the starter with a hammer. You may also want to try to jump the terminals on the starter if that tapping doesn't help.