KA-T 2.4 need to re-torque head

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scoobydo
Driving Mom's Station Wagon
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Joined: Tue Oct 13, 2015 4:12 am

KA-T 2.4 need to re-torque head

Post by scoobydo »

Loose water every 300 miles or so. On investigation no external leaks found. Pressurerised the coolant system to 1.4 bar via expansion outlet and left for 1 week with no drop of pressure or external water leak. on Starting the van, some white smoke present :-( So put the pressure back into the system and left for 5 days once again no loss of pressure on gauge. Took out plugs and found less than 5ml of water sitting on top of piston 3.

How would you guys go about tightening the head down. Not an exact science but when I look at the ARPS on cylinder 3 and 4 there is less thread showing so maybe it is as simple as a tighten required? Have took the front upper cover off and the engine has JWT sprockets on the cams. Going to be tight to get the socket and breaker bar on the cams bolt but hopefully can rig something up. So I need to have the cams opposing each other on number 1 cylinder (valves closed) crank on or around TDC or at least on a reference point on the front timing mark (I dont have the 6 timing marks on the crank pulley) but do have a couple that I can use near TDC. Zip tie the upper chain to the sprockets and compress upper chain tensioner (is there something about using a nail or something to keep it compressed). Use 1 inch AF spanner on front of cam to hold that steady and get the bolt out the cams then undo all the journals on the cam and tighten ARPS to 77ft lbs? I plan to then re-commision water system before putting cams back in and pressure test again to see if any water in cylinder. Anything I have missed or any tips?

Tks
scoobydo
Driving Mom's Station Wagon
Posts: 35
Joined: Tue Oct 13, 2015 4:12 am

Re: KA-T 2.4 need to re-torque head

Post by scoobydo »

Well cams out and the nuts were less than 55lbs with the most "loose" being the ones next to the cylinder that shows slight coolant leak. Have re-torqued to 86lbs and system under test at 1.2 bar and so far no pressure loss in 20hrs. It is on ARP's and cometic HG. Would you guys loosen say 1/4 turn and re torque in one smooth movement each nut individually after it has settled (been bolted down at 86lbs for 4 days). Or leave alone? BTW running 25psi
scoobydo
Driving Mom's Station Wagon
Posts: 35
Joined: Tue Oct 13, 2015 4:12 am

Re: KA-T 2.4 need to re-torque head

Post by scoobydo »

Put everything back together and have run the car so far so good but need to put some mileage on it. Will put another post on about something else I noticed.
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p00t
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Re: KA-T 2.4 need to re-torque head

Post by p00t »

If your headstud nuts are getting loose it is probably because the bottom of the threads in the block are full of crap or the last few threads need to be tapped.

Next time you are in there get a bottoming tap in 10mmx1.5 and chase the threads all the way down. Clean out the holes with carb clean and blasts from an airgun from an air compressor. Then you will hold the torque and not need to re-tighten. It's good practice on a composite gasket but there is no reason to retorque on the metal ones.

Also I give a thin even coat of copper gasket spray to the HG. It will fill in any tiny scratches on the head or block surface when you torque down.

Also use the stock washers or better ARP ones that someone found on here (search). The standard ARPs are too small and will sink into the aluminum also doing the same thing.
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JustAlex
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Re: KA-T 2.4 need to re-torque head

Post by JustAlex »

p00t wrote:If your headstud nuts are getting loose it is probably because the bottom of the threads in the block are full of crap or the last few threads need to be tapped.

Next time you are in there get a bottoming tap in 10mmx1.5 and chase the threads all the way down. Clean out the holes with carb clean and blasts from an airgun from an air compressor. Then you will hold the torque and not need to re-tighten. It's good practice on a composite gasket but there is no reason to retorque on the metal ones.

Also I give a thin even coat of copper gasket spray to the HG. It will fill in any tiny scratches on the head or block surface when you torque down.

Also use the stock washers or better ARP ones that someone found on here (search). The standard ARPs are too small and will sink into the aluminum also doing the same thing.
Was just thinking this. I was surprised when I chased the threads on my last KA, definitely would've caused some problems with how dirty they were.. And good info on the washers.
scoobydo
Driving Mom's Station Wagon
Posts: 35
Joined: Tue Oct 13, 2015 4:12 am

Re: KA-T 2.4 need to re-torque head

Post by scoobydo »

I like to keep things updated. The gasket/head was no good in the end. Had to do the right thing and get it skimmed and I put a felpro on and so far so good.
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