1978 280Z 2+2 Cylinder Head Removal

[MillerTime802]

I could use a bit of advice here.

History: My daughter just purchased this Z, reported to have only 40,000 original miles, really good condition with tons of original parts, interior and exterior. It has fuel injection. She's no mechanic, graduated college, and loves old Zs.

Problem She had a water leak, repaired the loose hose clamp (losing most all the water) and drove the car to Auto Zone to get coolant. Here in lies the problem, the car overheated (duh), she said she'd stop when the temp gauge got hot, let it cool, and resumed her trip. Apparently she blew a head gasket (warped the head?), and water is now in the crank case (white oil on the dipstick). She reports that when she adds water, it disappears, but not on the ground. The engine still runs good (I told her not to start it again), but blew white smoke out the tail pipe when she ran it.

Assistance Appreciated I'm 60 yrs old now and have been a back yard mechanic all my life, but for years, I just pay someone to fix my stuff. I volunteered to "mechanic" on this thing to save her dollars.

Does anyone have any good advice for removing the head on this thing. You Tube videos, on-line service manuals, helpful hints??????? I have my Haynes from the 1971 240 Z I owned, but it doesn't show fuel injection.

Thanks for any advice you have, except the obvious......pay a real mechanic, ha.

Edited April 11, 2013 by MillerTime802

[EuroDat]

Hi Millertime, Welcome to the club and forum.

You can download the FSM (factory service manual) from Xenon30 XenonS30. If you scroll down you willalso find a handy Fuel Injection Troubleshooting manual in the "Other Guides" section.

Lookslike you will have to take the head off. If you are lucky its just a head gasket, but I would be preparedfor more problems.

Goodluck

Chas

[MillerTime802]

Thanks your quick reply, Chas. I'll visit the site.

[siteunseen]

Here you go, step by step with pictures...http://www.classiczcars.com/forums/articles-our-members/42420-77-280z-head-removal-%5Bstep-step-photos%5D.html

[LeonV]

STOP! Do a compression test first. Let us know the results.

[71Nissan240Z]

Yeah. You should do a compression test. Leakdown would actually be better. Because it will steer u to where and what cylinder is having problems sealing.

[MillerTime802]

Yeah. You should do a compression test. Leakdown would actually be better. Because it will steer u to where and what cylinder is having problems sealing.

Thanks for the input guys. I'll do a compression check tomorrow evening and post my findings this Saturday.

[MillerTime802]

@ SiteUnseen: Great guide. Thank you very much. I printed it out, 3 ring binder, compression test coming, and then, I'm sure, head removal. I'll post updates if I can figure out how to insert photos. Brad

P.S. Thanks for the addendum's offered by others, and the humor (Monty Python's Lumberjack:....I work all night and sleep all day!)

Here you go, step by step with pictures...http://www.classiczcars.com/forums/articles-our-members/42420-77-280z-head-removal-%5Bstep-step-photos%5D.html

Edited April 12, 2013 by MillerTime802

[MillerTime802]

Update:

#4 cylinder low compression. Pulled the head (N-47). Crack in the combustion chamber thru the valve seat......darn. It's obvious the top end has been worked on in the past. The pistons and block look good, but has a lot of carbon build up on the piston tops.

Daughter purchased a used complete head (P-79), it looks identical except it has a closed chamber in lieu of the open chamber head I removed from the block.

Are these 2 heads interchangable?

I'm planning on attaching some photos tomorrow, if I can figure out how to do it.

Anyone have any opinions or info to share.

Edited April 15, 2013 by MillerTime802

[EuroDat]

Thats bad luck with the crack in nr. 4.

You didnt mention which head codes you have? 280Z will have a N42 or a N47. They are not the same, the N47 has round exhaust ports, emmision liners in the exhaust ports and an internal oiled cam. The N42 is considered the better of the two.

The N47 is known to have problems of cracking around the vavle seats.

Dont scrape the carbon of the pistons, it can get down in the rings are scratch the bore. Best left alone

Chas

[MillerTime802]

Chas: I updated my post to include the head codes. But they are as follows: N-47 (head removed from block) and P-79 (the used head my daughter purchased). Do you know if these are interchangeable? Thanks, Brad.

PS: the block is an N-42.

Edited April 15, 2013 by MillerTime802

[Captain Obvious]

So, you've got a 280 that came to you with an N-42 block and a N-47 head and you're wondering if you can replace your cracked N-47 head with a P-79 off a 280ZX?

Is that right?