z24 head waterways

[Jeno007]

I recently bought a 620 from a fellow, with a carbureted z24 (don't have the foggiest why the l20 got ditched) and the head gasket blew shortly after (exhaust in water and vice versa). After pulling the head, see that it blew between 3 and 4 (crack in gasket rings). But after looking at the gasket that came off and the new one, all of the waterways are blocked by the gasket between the head and block. Is this supposed to be so to improve cooling in some way or is there something amiss? Thanks in advance.

[datzenmike]

Surely not ALL the water ways are blocked.... Is the gasket upside down? Look for the tiny oil supply hole from block to head between #3 and #4 cylinders just above the oil pressure sender.

 

If you have a Z24 (8 spark plugs 2 coils) and you get a Z24 head gasket it should work just fine.

 

Post a picture of them???

[Lockleaf]

In general, yes many of the water pathways are blocked. This forces coolant to actually cycle all the way to the back of the block. They should be open toward the back of the motor.

[Jeno007]

All waterways, save one tiny hole in one. Will take a minute to figure out how to post pictures.

[Jeno007]

https://scontent-sea1-1.xx.fbcdn.net/v/t31.0-8/fr/cp0/e15/q65/18815301_10155426470042028_6532366969391282372_o.jpg?efg=eyJpIjoidCJ9&oh=914f01f399ea46ad3cdfa3f209fedcb5&oe=59B79E6F

[Jeno007]

Well that's not it, lol.

[Jeno007]

So, not seeing the button that the site tutorial says will allow me to share images. But the first link I posted is of the head, waterways at the bottom. Second I'm posting now is of the gasket in place, covering the waterways.

 

https://scontent-sea1-1.xx.fbcdn.net/v/t31.0-8/fr/cp0/e15/q65/18891614_10155426470552028_1967533611379561743_o.jpg?efg=eyJpIjoidCJ9&oh=0f7ffd5d4d51f1d0d2b2fbd2a10d6899&oe=59B77531

[Jeno007]

If anyone could even show a photo of the head gasket with the waterways that are clear that would be awesome. Cross referenced years and searching the net is coming up with nothing but the same gasket. And it's making zero sense as there has to be a way for water to exchange through the head, and it's seeming like this may have been some of the problem.

[Lockleaf]

There's nothing wrong with that gasket. A bunch of those holes are water passages. Some are oil but not all. Do not open those holes. Engine will cool LESS effectively.

[shacks510]

The Z24 has less water passages than the L series, if that's what you're asking.

 

I have an LZ hybrid motor and noticed when I was modifying a new headgasket that a water hole was missing at the front on the new gasket right behind the timing cover area.

[Jeno007]

Hmm, at the bottom of the head in the photo aren't supposed to flow? Top appears to be oil galleys, how is the head supposed to cool and what would the reason be for having matched waterways between the head and block if they're blocked by the gasket?

[datzenmike]

There is a very small oil supply up into the head to lube the cam located directly above the oil pressure sender. Usually it  has a copper seal. There is an oil drain back hole at the very back of the head and block, about the size of your thumb..

 

 

The L series have more holes on the left side because both manifolds are on that side. There is need for more coolant flow in the head in this area because the hot exhaust ports are right beside the intakes. On the Z series the intake is on the opposite side from the exhaust.

[Stoffregen Motorsports]

Hmm, at the bottom of the head in the photo aren't supposed to flow? Top appears to be oil galleys, how is the head supposed to cool and what would the reason be for having matched waterways between the head and block if they're blocked by the gasket?

 

In general, yes many of the water pathways are blocked. This forces coolant to actually cycle all the way to the back of the block. They should be open toward the back of the motor.

 

The question has already been answered.

[Jeno007]

Well, don't feel comfortable with it, but I'll put it together and see what happens. Thanks fellas.