Head gasket issue?

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scoobydo
Driving Mom's Station Wagon
Posts: 26
Joined: Tue Oct 13, 2015 4:12 am

Head gasket issue?

Post by scoobydo » Sat Jul 13, 2019 1:55 pm

Seems like I have a HG issue. Water was being pushed into the expansion tanks (non pressurised catch can). Car is on a cometic MLS GH, and ARP studs. Just done a leaddown test and on cylinder 3 it is pushing into the water (radiator level rises slowly). Car has never been right since purchasing it but now have some time to try and sort it. Orignal seller reckon air lock or leak but I proved this was not the case and now have performed some more tests and have proven the issue without doubt. As we know on these heads it is cams out to get at the head studs. Anyone think a slacken off and 3 stage torque up could resolve the minor breach? Note got no steam out the exhaust compression on number 3 is 8 percent down to the other 3 cylinders. Maybe clutching at straws but worth a go?

BTW if I do need to take the head off, would I expect to be able to see the part number of the current gasket?

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p00t
Encyclopedia-Nissan
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Location: Detroit

Re: Head gasket issue?

Post by p00t » Tue Jul 16, 2019 12:22 pm

I don't see any way around taking the head off. Make note of any headstud nut that feels looser than it should. If you find some take the studs out then clean and tap the threads with an m10 bottoming tap.

You need to see the condition of the gasket and cylinder before making any decisions and the head needs to come off to clean the threads in the block. Good luck.
Current Experiment: APS SR56, Methanol Injection, & Built Block

scoobydo
Driving Mom's Station Wagon
Posts: 26
Joined: Tue Oct 13, 2015 4:12 am

Re: Head gasket issue?

Post by scoobydo » Wed Jul 17, 2019 1:33 pm

Head is off. nothing too obvious on the gasket or valves. TBH witness marks around the cylinder were not even do cometic have sealing rings as not evidence. I did try and re torque head but still leakage under leak down test. All bolts torque to 74 foot lbs. Going to post another thread about the FEL-PRO 26171PT assume that is the one that i popular on here?

scoobydo
Driving Mom's Station Wagon
Posts: 26
Joined: Tue Oct 13, 2015 4:12 am

Re: Head gasket issue?

Post by scoobydo » Wed Jul 17, 2019 1:33 pm

Head is off. nothing too obvious on the gasket or valves. TBH witness marks around the cylinder were not even do cometic have sealing rings as not evidence. I did try and re torque head but still leakage under leak down test. All bolts torque to 74 foot lbs. Going to post another thread about the FEL-PRO 26171PT assume that is the one that i popular on here?

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p00t
Encyclopedia-Nissan
Posts: 1080
Joined: Sun Aug 28, 2005 10:27 pm
Location: Detroit

Re: Head gasket issue?

Post by p00t » Wed Jul 17, 2019 9:15 pm

Sounds like the head may be warped and need resurfacing. Check the block (usually okay) and head with a straight edge. Also check for any marks from "aggressive" sanding/cleaning on the head surface.

I would give the the cometic one last try after addressing the head. Many people are able to reuse them. Spray a thin coat of copper gasket (aerosol type can) onto the gasket before reinstalling.

I've had my cometic off once and no issue with the reinstall.
Current Experiment: APS SR56, Methanol Injection, & Built Block

scoobydo
Driving Mom's Station Wagon
Posts: 26
Joined: Tue Oct 13, 2015 4:12 am

Re: Head gasket issue?

Post by scoobydo » Wed Aug 28, 2019 1:03 pm

So felpro installed and no issues :-) Whilst in there checked valve lash and it was all over the place and didnt match the clearances given on the cam card so was badly shimmed at stock values. Once reshimmed then moved onto the timing and the inlet cam is 9.5 degrees out should be 12 ATDC and got 21.5 ATDC so can get that by retarding on the JWT cam sprocket. Exhaust open at 40.1 BBDC and should be 47 BBDC so can advance that on the sprocket.

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