'72 240Z Rebuild

[siteunseen]

I'm about to tear this motor out and then apart.  It's kind of hard to do because it runs pretty good today but I can't trust a 43 year old motor's stamina, so here I go.

 

I think updating this thread with the progression of the build will save my butt from mistakes with the help of the forum.   

 

My plan is to remove the carbs first then the head and then block and transmission.  I know the basics, label and bag everything and clean, clean, clean.  I did my 280 a couple of years ago with step by step instructions from Tom Monroe.

 

I'm feeling a little sick knowing what I'm about to do but these beers are helping.

 

Thanks,

Cliff

 

[nix240z]

I still remember rebuilding my 240z motor 32 years ago when i was 16 and that motor still runs strong today.

 

good luck

 

Steve

[bvolken]

Please take advantage of my site. I tried to document as much as I have time for!  WoodWorkerB.com

I'd love to add links to your learnings!

[djwarner]

Cliff,

 

I'll watch this thread with interest as I will be doing a bottom end overall myself later this year on my 185K mile engine. My problem is bad oil consumption across the rings. My head was rebuilt in 2002 and pulls very good compression and vacuum, so I will be spared half an overhaul.

 

The only other problem is a worn timing chain and tensioner. I've been slowly accumulating parts and tools for the job, needing only engine block paint and main and rod bearings. Figured I'll have to wait until the crank is pulled to see whether I'll need a regrind and undersized bearings.

 

I took the advice of others on the forum and purchased Tom Monroe's book. My overhaul will be a little different than yours. I am leaving the automatic transmission in place and simply pulling the engine. 

 

One point from your post. Why are your removing the head before pulling the engine? I thought the aft-most exhaust manifold stud is the best point to attach the hoist chain.

[madkaw]

So Cliff, is this the motor that's hauling you to Zcon 2015? If so, we are in the same boat. I was thinking of documenting my 'redo' of my l24, but maybe just throw some comparisons in on your thread?

I'm a little further than you in that my block is sitting here cleaned and rehoned with my crank polished.

You are having a machine shop prep everything?(rods, crank, etc...)

[siteunseen]

65 degrees here yesterday.  I cleaned up and out my garage then drove the little car for the rest of the day.  Those new 15x7s with 205-50s make all the difference in the world.  Looks good and drives like it's on a rail.  Anyway, all I did last night was pull the hood off.  But today I'm filling up some boxes and baggies. 

 

DJ that book was crucial when I rebuilt my very 1st car engine, my '77 280.  I'd only took the top end off dirt bikes then in the early 90s I learned how to work on outboard motors by working with a mechanic while I was healing after an ankle fusion surgery.  He turned out to be a good friend that I'm still in touch with today, Dr Brown we call him.  I had a 2.5 liter Mercury V6 with OMC carburetors that would turn 9,200 RPMs with a 24 pitch prop.  8,000 with a 26 or 28 prop (can't remember) was 102 MPH on a handheld GPS I had in a pouch on back of the driver's seat.  1,200 lb boat and motor I raced 1/4 mile side by side "run what you brung".  It was a '83 Hydrostream Vector. 

 

Sorry about that, great memories from then.  Anyway I have to do everything by myself and taking the engine apart piece by piece is the easiest way for me without banging the car up.  After getting the top off I put 2 head bolts in the block and lifted it out with a hoist.  It may take a little longer but I tend to make mistakes when I try to do too much at once.  I let the 280 motor worry me to death, not going to happen with the 240.  I've learned enough with Tom's book and the helpful members on here to have some confidence now, plus the 240 is so basic and simple I can hardly wait to tear into it.

 

I'm going to take the block and head to the machinist in North Georgia.  They're going to set up the valve train and notch my block for the exhaust valves.  Port match and anything else I can afford.

When I take it apart, if there's anything that looks suspect I'll have it checked out by my local machine shop.  

[Patcon]

Very good. Enjoy the pretty weather. 102 mph on the water is "hauling the mail"!

Charles

[rossiz]

my eyes will also be on this thread... my f54/p79 build will progress sloooooowly, as it is being "trickle-funded" so i will have plenty of time to watch and learn.

thanks for posting up for the benefit of us all.

[siteunseen]

Finally getting down to the motor.  Hood is under one bed, radiator under another.  Carbs are on an extra intake mounted to a wall.  Everything is coming off pretty easy so far, exhaust manifold is going to be a booger.  I'm getting a friend to come by today and suck the R12 out of my A/C, don't know if I'll be putting all that mess back on.  

 

MSA's got a free shipping deal through the 16th so I'll order my exhaust in the next couple of days.  

 

Oh my aching back!

[rossiz]

progress seems to come with an aching back.

it's the one downside to these low-slung sports coupes - serious 'bend-over factor' when working under the hood. i find myself taking a 'wide stance' to get lower and keeping one palm on the hood latch bracket otherwise just changing the plugs is enough to get me feeling much older than i am...

 

the exhaust manifold is a pita, but once it's off you're just about done. i wrapped my u-joint socket adaptor w/some electrical tape to keep it from flopping around when trying to reach some of those hidden stud nuts, this was a great help.

[Zed Head]

Saw this on zcar.  They're standard bore so if you go over not much use.  But might be useful if the bores are good but pistons not.

 

http://www.zcar.com/forum/19-sale-parts-accessories/367049-nos-piston-wrist-pin-set-l24-flat-top-240z.html

 

 

 

Tried to learn what "Ttt" means but all the internet came up with is "third tier toilet".  Not sure why he says that...

 

Also, just because it's interesting - http://www.art-piston.co.jp/en/profile.htm

[Captain Obvious]

I'm no expert on popular forum lingo, but I believe ttt means "To the top".

 

Used to refresh and bump threads to the top of the display.