1HZ Head Gasket

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New head came in from Toyota today. I have all the parts to get it back together minus the port for the ACSD. I can find this part # anywhere or in my FSM. Can anyone give a hand? I’m thinking this port is on a number of engines?

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This is a good time to delete the ACSD....


But if you do want to keep it, the port PN: 90406-10014 and 90561-09014
 
Thanks - I was under the impression you still keep that port, run the hose and splice it into the other hose that joined the IP. I'll look more then.
 
The process of lapping valves has begun but I cannot locate one of the freeze plug heater pipe outlets to get back in the head. Looks like it’s out of stock everywhere - none at Toyota or partsouq, Amayama, etc. I can’t find one to save my life. If anyone knows, let me know.

PIPE, WATER BY-PASS, NO.3​

Genuine Toyota, Genuine Hino (1627917010)​

 
After too long waiting to receive everything I need and have the head back on, it’s mated back up. Let me just say how fun it was getting the head back up and over the front end of a lifted truck by myself. I got creative and had a 6”x14”, laid it on over the radiator so it pivoted over the engine bay on to the ground, lifted the head on the board, slid it down over the block, the weight of the head dropped the board down over the block and then finally lifted it on the block. White trash work. I sat in bed last night with a tens machine shocking my back for 2 hours from the aftermath.

New head is thankfully on. Next up is torquing and fitting it all back.

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I got most everything put back together. Upon turning the engine over via the crank, the TB seems awfully loose on the compression stroke; meaning there seems to be a lot of slack. It tightens up as you rotate, but doesn’t feel right. I marked everything, including the old TB just to be safe and put it all back just how it was. Not sure what’s going on there?

Timing belt was done about 6 years ago. Just to be safe, I ordered a new spring and tensioner to see if that helps. The one on there looks fine, but figured it’s fine to be insured.

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Waiting for the new tensioner and spring to come in. After watching a few videos and going over it again, I’m not sure why there is slack on the “top side” of the belt from the cam to the pump on the stroke. Maybe the tensioner will help.
 
After putting it all back the way the book demanded, pumping the fuel primer around 9,000 times, bleeding the lines and cranking it once, it started right. The first time it cranked right up. Sounds really good too. The only thing I need to figure out is when this all started and I was flushing the radiator with the hose, I got water in somewhere and the AT temp, filter and charge light are staying on. Something is still not dry.

And so it ends. Now I get to drive the cheapest and rustiest 70 I’ve ever owned. Thanks all for the advice and solidarity. Special thanks to Onur who responded to my mid-wit questions.

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Maybe the saga is not over.

After putting head back on I’ve driven this truck short stints (around 20 mins or less) and noticed that the upper rad hose is getting firm. Not like it was for sure, but still has some pressure. It’s not rock-hard. With the cap off, and idling for 10 mins or so, the coolant will slowly rise - not much, but it has flowed over and out of the radiator a small amount. I’m wondering if I have not bled the system enough or if at all.

Truck doesn’t run hot at all. I have not put a temp gauge on it, but it hasn’t reached half way point letting it fast idle or driving it. Stays cool. Also, there is no blow-by at with the upside-down oil cap or hand. Pretty great. Power is less that to be desired, but it’s an automatic 1HZ.

I’m obviously hoping this is not the alternative with the HG. I’m tracing a electrical issue in another thread, and have the alternator off, so can’t do a exhaust gas test yet.

Thoughts? Talk me off the ledge?
 
Yes, I did. It has rear heat as well.

With the heat on, it has never got up to temp.
 
What's the issue? The radiator cap has an opening pressure of something like 0.9 bar (gague) so some pressurisation is normal. Thermal expansion of the coolant leading to overflow of an open radiator cap is also normal. A big diesel will not get up to temp for a long time when idling.

I assume you have as a matter of course replaced tha radiator cap and either tested or renewed the thermostat.
 
Yeah, new thermostat on it when I was in there with the WP. I put a .9 bar cap on it.

I’m hoping no issue at all with this.
 
Maybe the saga is not over.

After putting head back on I’ve driven this truck short stints (around 20 mins or less) and noticed that the upper rad hose is getting firm. Not like it was for sure, but still has some pressure. It’s not rock-hard. With the cap off, and idling for 10 mins or so, the coolant will slowly rise - not much, but it has flowed over and out of the radiator a small amount. I’m wondering if I have not bled the system enough or if at all.

Truck doesn’t run hot at all. I have not put a temp gauge on it, but it hasn’t reached half way point letting it fast idle or driving it. Stays cool. Also, there is no blow-by at with the upside-down oil cap or hand. Pretty great. Power is less that to be desired, but it’s an automatic 1HZ.

I’m obviously hoping this is not the alternative with the HG. I’m tracing a electrical issue in another thread, and have the alternator off, so can’t do a exhaust gas test yet.

Thoughts? Talk me off the ledge?
I have noticed this with several 1HZ's where I couldn't find anything else wrong with it . It is just one engine vs another and these 1HZ's pretty much all drive and feel different which I think has something to do with the previous decades of use and in particular how they where driven and maintained . Best test is to get it out on the highway at 75 mph for a bit and if anything is wrong it will show you .
 
I started another thread as I’m having some electrical issues now. The new rectifier/regulator supposed to show up today so I should have the alternator back on and driving this weekend. Nasty burnt electrical smells coming from the voltage regulator…

I’ve never seen anything like it although my Tacoma has a .9 bar radiator cap and usually has a soft upper rad hose. I swapped it with the 1HZ and now it’s firm on the Tacoma upon a short time running. Who knows, maybe it’s that simple.
 
Just an update here: I’m on my second oil change since the new head, etc. and no issues thus far. I don’t think I flushed the rad enough as I’m getting some crap in the overflow, but other than that it’s doing great after 1500 miles or so. I need to get rid of the auto box so if anyone has a 5-speed spare in SC, GA or NC, I would be open.
 
First off, this is loads of fun pulling a head off a block by yourself. I’m taking a break as I think I threw my back out. I haven’t got the head all the way out yet so i don’t know about cracks yet. My wife refuses to help.

Time for a liquid reward.

Looks like some nice coolant there…

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Next time channel your inner redneck, set up your own franken-hoist and save your back....money well spent

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