ka24e Engine assembly

[alexg89]

So ive had the truck down for some time now and ive been gathering parts for the rebuild..

I have never put together my own engine so i gots a few questions.

first off, plastigauge, is this to be used?? i have the factory assembly manual and i skimmed it and it just looked like torque values.

second, balancing, i have some Arias 11:1s that are going in. Do i need to have everything rebalanced? or can i stick them in and run it?

 

[datzenmike]

Plasti-gauge is excellent for checking bearing clearances. You're looking for big whoops. It's not like having expensive measuring devices but well within 'good enough'.

 

Balancing? I don't think so. All Nissan reciprocating parts are balanced separately so that replacement pistons and rods and such can be bought and installed if needed. A Z22 can take KA24E pistons to make a 2.3 and I've never heard of balancing anything. You could check the pistons, pick out the lightest and grind down the others so they all weigh the exact same but I doubt this is necessary with Arias..

[alexg89]

With that being said looking for big whoops.. i know the crank and everything is still good and im going to have all new bearings.. how would a "whoops" show up?

IF everything is still functional and running it should all go together smoothly i would think.. but then again ive never done this lol

 

 

[Lockleaf]

Crank might be in good shape but that doesn't mean you can see thousandths of inch difference in diameters per journal.  Or identify a mismanufactured new bearing.  Plasigage tells you if things are in spec so you don't have to assume.

 

For $5 and a little extra work there is no good reason not to use and verify every bearing in its respective journal.

 

Torque values do not define bearing clearences.  You can't safely just change fastener torque to try to fix a clearance issue.

[alexg89]

3 minutes ago, Lockleaf said:

Torque values do not define bearing clearences.  You can't safely just change fastener torque to try to fix a clearance issue.

 

I understand that.. guess i need to take some lessons on how to use plastiguage

[datzenmike]

Rod and caps can go out of round.

 

Unbolt main or rod cap and clean surfaces. Put a length of Plasigage lengthwise on crank journal. lnstall cap and tighten to spec, remove cap and compare to the scale on the Plasigage package to find your clearance. Don't turn the crankshaft while doing this. It's just a cheap method to look for assurances that everything is ok.

[demo243]

Plasti Gauge is really simple to use- just as DatzenMike said - adds a step of assembly and reassembly, but doesnt take long. If all checks out then lube it up and torque it all properly. 

 

I was nervous about building my KA24DE, but the whole process is pretty simple. Just take your time, double check yourself and use a torque wrench. I picked up some bar style torque wrenches as they are supposed to be more accurate then the clickers... Idk... I did like that I could see the torque progressing instead of blindly waiting for a click, especially on the low torque alloy threads.

Edited June 12, 2020 by demo243

[Stoffregen Motorsports]

Making sure the rotating assembly is put together properly is super crucial. Bearing clearances are important, but just as important are checking and setting the thrust bearing, keeping the burrs on the block bearing saddles from scoring a bearing as you slip it in place, making sure the caps are knocked into place in a way that seats them but doesn't knock the bearing loose.

 

Before any engine build, I always "dress" the block. This means taking off all the sharp edges with emery cloth and a file, chamfering of all oil holes, bolt holes, any hole, and basically making sure that there are no burrs of any kind in the bottom end. The tops of the bores can be chamfered too, with emery cloth. This is done at the top edge of the bore, to make sure there are no sharp edges which could score a piston or break a ring when installing the pistons.

 

If you want to tap any holes or clean any galleys, now is the time to do it.

 

After the block is all prepped, it's best to do a thrust mock up. Install all the main bearings and a drop of oil on each one (no more), set the crank in place and before you install any main caps, measure the thrust of the crank (the fore-aft movement of the crank in the block). It should be around .006". Now set the center main bearing cap (with bearing) on the block, tap it in pace gently, tighten the bolts snug, then gently smack the back of the crank with a hammer. This aligns the two halves of the thrust bearing. Torque the center main cap bolts and check the thrust again. It should not have changed from your first measurement. I like to use a dial indicator on a magnetic base to measure the thrust, but it can be done with feeler gauges.

 

I've got a ton more to say, if you want to hear it...

[grannyknot]

Or, you could buy those expensive measuring tools once and use them for the rest of your life, you want to know what your clearance is, measure it.

[alexg89]

Wish one of yall were near central fl and I would pay you to teach me . Im 31 and I feel ashamed I don't know this lol

[datzenmike]

40 minutes ago, grannyknot said:

Or, you could buy those expensive measuring tools once and use them for the rest of your life, you want to know what your clearance is, measure it.

 

Rent or borrow maybe. Too expensive for the average guy rebuilding he engine. As I said definitely 'good enough' for piece of mind checking

[Stoffregen Motorsports]

$70 dial bore gauge for measuring installed bearings and cylinder bores - https://www.amazon.com/Extender-50-160MM-）Indicator-Resolution-Internal/dp/B07Z7MCBTJ/ref=zg_bs_401577011_7?_encoding=UTF8&psc=1&refRID=JKMN3PX9PWG9RXSB8BS9

 

$90 mic set covers rod journals, main journals and most piston sizes - https://www.amazon.com/Anytime-Tools-Micrometer-Precision-Machinist/dp/B0045UZGSC

 

$50 dial indicator on handy wobbly base for checking endplay, cam timing, etc - https://www.amazon.com/Steelman-60378-Brake-Runout-Indicator/dp/B07HJK7MN4/ref=sr_1_1?dchild=1&keywords=steelman+60378&qid=1592004548&s=automotive&sr=1-1

 

That's $210 worth of tools that have many uses. I use my wobbly base dial indicator all the time. On the lathe, checking R&P backlash, cam timing...

[Stoffregen Motorsports]

57 minutes ago, alexg89 said:

Wish one of yall were near central fl and I would pay you to teach me . Im 31 and I feel ashamed I don't know this lol

Teach a man to fish...

[grannyknot]

23 hours ago, datzenmike said:

 

Rent or borrow maybe. Too expensive for the average guy rebuilding he engine. As I said definitely 'good enough' for piece of mind checking

For me any excuse to buy another tool is a good thing but I also think about age of the Plasti Gauge, how long has it been on the shelf, how was it stored and how will that affect the accuracy of the reading?  Probably not a big deal.

[datzenmike]

Plastic, probably infinite shelf life.

[DanielC]

I believe plasti-gage is actually wax, any traces of it dissolves in the oil.

[datzenmike]

Waxi-Gauge then.

 

Had to look it up but, wax

[demo243]

On 6/12/2020 at 6:34 PM, alexg89 said:

Wish one of yall were near central fl and I would pay you to teach me . Im 31 and I feel ashamed I don't know this lol

 Don’t over think it. Built my KA at 28? Didn’t know about any of this shit... downloaded a factory service manual and got lucky found a build thread that still had pictures to walk through it.

 

overall it’s actually pretty simple stuff. Just turning wrenches essentially... just gotta do it all in the right order and to the right torque 

[alexg89]

23 hours ago, demo243 said:

 Don’t over think it. Built my KA at 28? Didn’t know about any of this shit... downloaded a factory service manual and got lucky found a build thread that still had pictures to walk through it.

 

overall it’s actually pretty simple stuff. Just turning wrenches essentially... just gotta do it all in the right order and to the right torque 

Yah i know just be more piece of mind. I can do just about anything on the truck but i just have not done engine assembly. Ive got a copy of the FSM. ill probably be ok but i just hate to trash something im putting together over something stupid you know..

 

[Stoffregen Motorsports]

There is a learning curve for sure. Mainly, just be aware of what you're doing. Pay attention to even the tiniest details to make sure you don't scratch a bearing while inserting it or hit the rods on the crank while installing the pistons. Oh yeah, buy yourself some rod bolt protectors too. They are cheap - https://www.summitracing.com/parts/cle-2800b1

[scooter]

Youll be okay. Just leave the oil pan off the bottom half and valve cover before you go to bed so when you wake up in the middle of the night wide eyed cause you forgot to check something you can run into the garage in your underwear to re-assure yourself. Dont be afraid to go back and check to make sure the bottom end is torqued up properly. 

 

If your file fitting the rings if you go a little on the loose side it wont be a catastrophe, well within reason. Dont cut the oil ring down just make sure the oil ring rails dont butt together in the bore. 

Make sure you deburr the edges you filed on the ring so it cant bite into the ring lands.

 

cleanliness is next to godliness.

 

if u glue any of the gaskets just do one side so if you need to back up a step you dont make a gnarly mess for yourself.

 

make sure your rods are in the correct way and your pistons arent backwards :)

rod oil squirter hole towards drivers side of block (thrust side) your pistons should have an arrow or a valve relief or something blatantly obvious.

 

for balance, inline 4 and 6’s are neutrally balanced and do not require a bobweight style balance job that v8’s do. To do rods properly you should make a fixture to weigh the small end and big end of the rods and match them that way. If your not revving it much more than the stock limit its probably good enough for your first one in my opinion though. 

[Lockleaf]

My best advice, don't install your main bearings upside down and thereby cover the oil galleys for all the bearings.  I most definitely did not destroy the first engine i ever rebuilt by doing exactly that...

[grannyknot]

4 hours ago, Lockleaf said:

My best advice, don't install your main bearings upside down and thereby cover the oil galleys for all the bearings

Oh you buggar, I finished assembly of my KA24DE a month or so ago and now you've got me second guessing myself.