NcTwOfOuRtY

yea that exact same shiot happened to me goin to nopi lol ironic my sotry is about the same in detail also but my head is done, and as for where my coolant went when we were setting the timing to tdc to tear down the motor it spewed out the #3 spark plug hole like old faithful lol it sucks we found a ka w/ 70,000 for $300 so we're just throwin that in since we already done all the work for the e-de swap for the motor that just messed up, and as for the one in there we're putting it to the side and building it for turbo. good luck with whichever route you chose

LA_phantom_240

meh... you said your head is done? Whats that supposed to mean? Lucky find. What year KA? See if i had the skills to rebuild the motor the way i want it, i would have no problem using my KA. Did you tear down the motor and see what the culprit was? Id like to see a pic to show my dad if you have one. He doesnt believe me. He thinks i was negligent and let it get hot and didnt watch the temp gauge. He's an idiot at times.

LA_phantom_240

BigVin... how the hell did you know what went wrong with my motor? That was amazing are you a psychic or a psycho? Where do you live, ima send you a stripper. You hit the timing chain dead on the head AFAIK. I took off the upper timing cover, and low and behold, no guide left, and a few fragments on the slope tapering down from the top of the front cover, toward the water pump. Now i just need to figure out if it jumped time (likely with this much play in it. So now can you tell me if i can tell (without pulling the head) if i bent the valves? If not, then it should be a not-so-expensive thing to fix. Headwork = ho. SOHC pistons and rods here i come.

Oh and bigvin, what do you think about this setup im thinking of.
Okay, first order of business, SOHC rods and pistons and rings to bring compression up to approx the same as those expensive-*** arias pistons. New SOHC pistons ($124 from summit, "Sealed power" brand) and rods(???) Thats cheaper and arias pistons ($400+) and new rods (???), and a header (DC or Hotshot), along with re-doing my timing chain and water pump stuff. Later on i would have the TB bored, the itnake runners extrude honed, i would pull the head off and do the DIY port/polish, and get better cams, though not int hat order.

Heres some pics!
Chocolate milk, nature's lubricant!


Gotta check the Chocolate Milk level in my crankcase. Look, its full.


A wonderful thing to find on your upper timing cover....


And for my final trick, the amazing disappearing timing chain guide act!

Now you see it...


Presto Change-o!!!
Now its gone!



...noisy bastard

BigVinnie

iTrader: (2)

People say that I anylize things too much, I guess I'm pshyco.

Heres the conflict of using a SOHC piston over the arias piston. SOHC KA piston is raised above deck heith this means that there will be complications running high lift cams (JWT,Brian Crower,PDM). Arias pistons are designed to take higher valve lift than the SOHC pistons. There is another alternative that I don't like to give out since this is knowledge handed to me by some well respected Datsun/Nissan tuners at the dime. You can use the NAPSZ 24piston which was manufactured from 1986-1990 for the Z24 engines in the hardbody trucks.
Here are the differences in compression
KA SOHCS 1990 pistons yield 11.1:1
Arias pistons yield 10.5:1
NAPSZ24 pistons yield 10.5:1, (or so I think)
The NAPSZ pistons have fly cuts in the pistons that would allow for higher lift cams, 10.5:1 is pretty standard when you want to run higher lift cams and is much more beneficial. I don't really like 11.1:1 cr for streetable pump gas. 10.5:1 would be much better, and if you could look for a much higher head gasket, to possibly drop compression just a tad more, especially if you plan on using the stock ecu tune. Topline is where I would go to get the pistons they are the biggest bang for your buck. I would ask devious KA if he has a raised head gasket available.
The head will need to come off and I can't determine valve damage I have no idea what happened just the basic formalities.
Looking at those cams though I would put them in oil immediatly to prevent any more corrosion or rust from occuring.
I would order new bucket hydraulics, and springs.
The block should be torn down and checked for stress fractures around the cylinder walls, chances are you are fine, but I would take the block into a shop and have it checked before ordering the piston size in stock size,.010,.020, .030, or.040.....
Then I would have the crank journals checked, if all is well get new beaqring and all new seals.
Sohc rods are fine, compiling together this high compression OEM build should cost under $1000 in parts.
SOHC rods are fine to use.

LA_phantom_240

...okay, so i need the napsz z24 pistons that came out of the hardbody pickup? z24 is the motor code right? 11.1 CR is no problem here in the south, we have 93 octane. ha. Hey vin, on ebay i saw these pistons, what do you think about the price and stuff? good deal? http://cgi.ebay.com/ebaymotors/NISSA...QQcmdZViewItem
Also, what rods would i need for that? How much do you think it would cost to have the crank balanced or knife edged or whatever? Any opinions on the windage tray and crank scrapers that were discussed on the forums here? My dad knows a lot about motors, espeically nissans. he used to have so many of those damn little datsun trucks you wouldnt believe. Anyways, um in not sending the block anywhere. Period. I dont have the kind of money to have someone take a look at it and say "yup, she's good to go" and fork out a hundred bucks. Besides, thats what i have a machine shop at my disposal for =D. Instead of having higher comp pistons i COULD have the machine shop mill my head down a bit. How do i calculate how much milling my head will raise CR? Like so many .xx mm = xx:1 CR?

BigVinnie

iTrader: (2)

I would contact the seller. That looks like a pretty lowered dish and no flycut. The KA rods work. I use to take KA sohc pistons to the NAPSZ block to raise CR. See if the seller would have any info on compression specs for the NAPSZ engine then I can do some math.
It would be a great purchase if I knew it ran a high enough CR, I also haven't heard of the company that makes those pistons.
You can mill the head to about .015 clearance in order not to interfear with valve clearance, that is also dependant on the gasket that you use. Milled heads show good results if done right, I've also seen some hack work with warped heads from doing that as well, all depends on how good the machinist is.
You can also try cloverleaf welding the head to raise the CR and still use the stock dohc pistons and not mill the head. There are so many different ways to raise the CR of the engine.
Crank scraper and windage trays are great, HP increase, lower oil tempratures, better lubrication of engine parts. Your dad would know what I am talking about.....

LA_phantom_240

I Could try to cloverleaf weld on the head? lol. 1st off, i dont like ruining parts cuz i cant weld for crap. and 2nd, its aluminum.... a PITA to weld. Ill go to a couple sites for the pistons and see what they look like compared to the celvite pistons. Clevite has been around for a long time. Theyre not like a uberjdm performance company, just oem spec stuff for the most part.

BigVinnie

iTrader: (2)

I wasn't trying to insinuate that you should weld the head, I was insisting that a professional should do it. I can't weld a head worth a crap either....LOLS

LA_phantom_240

...though i could have the machinists weld it solid and have them use the mill to cut out what i dont want welded... of course i wouldnt have them weld over the valve openings lol.

Also, there are like 4 z24 engines.. which pistons am i looking for? z24, z24i, z24l, z24i/s?

LA_phantom_240

Alright, it looks as if those pistons on ebay ARE the correct z24 pistons. Looked on advanceautoparts.com and looked up pistons for an 89 d21 (hardbody) pickup. Heres what advace shows.

Im probably going to get the ebay pistons in this case. What do you think bigvin?
These are the ones on ebay:

BigVinnie

iTrader: (2)

[QUOTE]Originally posted by LA_phantom_240
Alright, it looks as if those pistons on ebay ARE the correct z24 pistons. Looked on advanceautoparts.com and looked up pistons for an 89 d21 (hardbody) pickup. Heres what advace shows.

Im probably going to get the ebay pistons in this case. What do you think bigvin?
These are the ones on ebay:
[/QUOTE

Don't purchase them yet. I am going to double check my refrences to make shure they are the right ones. For some reason I remeber the flycuts at the ends of the pistons being deeper and the dish was shallower. Let me make shure first, or if you can comtact the seller first that would be good too.

BigVinnie

iTrader: (2)

Those pistons on ebay are not the right ones. I will search for the right ones. I am leaving the clevit PDF of all the manufactured pistons that they make for NAPSZ engines TC2332 was not listed in there catalogue, but I can tell you that it isn't the right one.
There were 4 different piston types for the usdm's depending on model year and if it was for car or truck. If thye search becomes too hard just get 1990 KAE pistons. I didn't think the search would be difficult... Sorry.
http://engineparts.com/products/Piston%20Specs.pdf

LA_phantom_240

wait, about the KAE pistons... I was told that the early models didnt have releifs, and the newer models did... also that the older model pistons arent in production anymore. Also, about the 1990 KAE pistons... do they have the CORRECT reliefs? Will the 1990 models still rise too high and not let me use higher lift cams?

LA_phantom_240

Okay Bigvin, i got everything from the radiator to the water pump off of the motor. I have a question though. Do the alternator PS pump and A/C compressor have to come off too? If so, how should i go about doing it? I have a few more items to add to my list of parts i need.
A Radiator, cuz mine looks like this:

And also, i found that my lower tensioner ISNT bad...*sigh*... As i went to pull off the water pump pulley, i decided to try to turn the motor clockwise (facing the motor) and watch the tensioner... as i turned it, it came out and put tension on the chain. ****. So why did my chain eat through the guide? Have i run it so hard that the chain stretched THAT much? im really lost on this one.

LA_phantom_240

Also, i found a front cover from a 95... will it work? heres the auciton link. Let me know what you think... http://cgi.ebay.com/ebaymotors/240SX...QQcmdZViewItem



Upon second thought... looks like ima have to pull the motor to get it out. ****.