Head gaskets and the 1FZ

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Mighty690

Mighty690

10 Year
Joined
Feb 8, 2014
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86
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1,108
Location
Julian, CA
When I first got into the petrol 80 Series I was lucky to learn about the PHH and more importantly the propensity for HG eventualities before buying one. My eyes were open.
We've read the various reasons: supposedly Toyota changed gasket materials (no more asbestos), people mixing red and green coolants, etc.
Here's my thought after having done a HG job on my 80: that big 'ol iron block is LONG. The aluminum head is long too and relatively light. That 4 valve head design leans toward the higher performance end of things (for a Land Cruiser of the period), and the block... not so much. Hey, they needed more power. Way different rates of expansion, with shear going on as well. Add a little overheating, and things start to get leaky. My engine, for example, didn't "blow" its head gasket, it just got weepy (like the radiator at around the same time). Blackstone said I was getting coolant in the oil, but with oil changes it could continue to operate.
My theory is that the 1FZ does a very good job at doing something that is fairly unreasonable to ask of such an engine design. Whoa. I know that's going to fire a few of you up. I'm not an engineer or a professional mechanic/tech, so I propose this question to those of you who are:
What other in-line 6 of this (or greater) displacement and torque figures, with a 24 valve aluminum head and a cast iron block is more reliable when it comes to head gaskets?
I don't know much about BMWs, but I know they developed their in-line 6's to the nth degree. And I know about the Supra...
 
From another thread: "This is why I keep advocate getting a Blackstone sample before buying an 80 - or just assume there is a head job in the near future. The more I hear about "recently purchased" 80's, the more I think a case of overheating, and the following suspicious HG issues, are pretty much the primary reasons people put their 80's up for sale. (Mudders excluded of course!) I mean, unless a person is facing a multi-thousand dollar repair bill why in the world would they sell a good Land Cruiser - particularly with current gas prices?"

This ought to promote some good discussion.
 
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The composite gaskets will always fail eventually no matter which coolant you use or which fastener you compress it with, using the good stuff simply prolongs the inevitable.

I've been down this road so many times I bought a plot of land and built a house on it.

It doesn't matter if you have a 7M(Turbo or not), 2JZ (turbo or not), 4G63 (turbo or not), or 4AGE (even 4A-C). They all kill head gaskets no matter how well taken care of.

Supra and Mitsu owners for years swore up and down to only use the factory gaskets, till slowly they started using MLS (Multiple Layer Steel) gaskets then all of a sudden they stopped eating gaskets.

There are a plethora of reasons why we (or toyota) shouldn't use composite gaskets but here are the ones that stand out to me.

1. US has the lowest oil quality standards making most of our oils caustic to gaskets.

2. Coolant contaminated by non-pure water, and internal corrosion/wear of engine and other components (Happens even in red coolant, have you checked your grounds lately? )

3. Factory fasteners stretch over time (well all fasteners do but it's the rate of stretch that is important)

We need a quality (aka not Cometic) MLS gasket with a stock or thinner compressed thickness. Until we have it the countdown timer keeps ticking.
 
Nice, Chi-man. But, what about my premise, that the fundamental issue is more fundamental than HG material?
 
The difference in the thermal coefficient of expansion of iron and aluminum is going to impart a difference of about 0.8 mm in the lenght of a 1FZE head compared to the block over a change of temperature of 100 degrees C or 180 degrees F, so that would cause a significant stress at the interface. A multilayer gasket would be able to handle this better than any composite gasket.
 
Thanks, Mr. Pin. Now we're cooking with gas!
 
Mighty690 said:
Nice, Chi-man. But, what about my premise, that the fundamental issue is more fundamental than HG material?
Click to expand...

Sorry, the issue is the material plain and simple.
 

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Interesting dicussion fellas, I just did mine a while back, I got all my parts from cdan so I'm sure they are the latest and greatest in Mr. T's eyes
 
If you make sure your mating surfaces are flat, and your bolts are within spec, a new OEM gasket should get you another 20 years. That's pretty good amount of time to be on the road. It may be that the original HG's on these trucks were prone to failure, but, these trucks have also been on the road for a long time. I would suspect the HG on any vehicle I purchased that was this old and had this many miles. Now would I use an MLS gasket if there were a good option for one, definitely.
 
Lots of discussions about this on here but-IDK if you caught that OEM gaskets were upgraded later-not aware of how other than the water passages at the end closed down somewhat to add more material. Of all the parts that people on here rave about OEM on this is the one that I'd use for a STOCK engine. Havent really searched specifically, but curious if any of those are going bad yet WITHOUT any abuse like overheating,etc. I'm sure any gasket will last a while but I don't want to be the quality tester.
 
I have had two headgaskets go. First went and the entire motor was replaced by Toyota. Second one went and it had the "new design" toyota head gasket in it. As far as I know I'm the only person who has blown a head gasket with the new design one. With my last rebuild I went with a new head and Cometic with ARPs and haven't looked back. 35k on the rebuild so far.
 
Kernal said:
Anyone familiar with Victor-Reinz MLS gaskets? Looks like they recently added the 1FZFE MLS gasket, appears to be 1.4mm thick, or about 0.055".

Last listing on page 37 in the file below:

http://www.victorreinz.com/img_cpm/002/files/Kataloge/2014/PKW/VICTOR-REINZ_PKW_TOYOTA.pdf

http://www.victorreinz.com/EN/Servi...ti-layer-Steel-MLS-Cylinder-Head-Gaskets.aspx

This is a good read about head gasket tips including failure analysis. FWIW.
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Stop the press! This could be really cool. Any opinions on this one? It seems the consensus has been the new Toyota gasket is good, and the cosmetic is great IF both mating surfaces (surfi?) are machined smoother. Could this be the missing link for those of me who want a new head gasket job on a boosted truck but don't want to pull the engine? Or just chill out and use the Toyota gasket?
 
Well, I did some searching and found a bunch of posts on victor reinz head gasket failures. No thanks
 
Just use the stock HG. I doubt you will run more than 16-17psi.

dogfishlake said:
Stop the press! This could be really cool. Any opinions on this one? It seems the consensus has been the new Toyota gasket is good, and the cosmetic is great IF both mating surfaces (surfi?) are machined smoother. Could this be the missing link for those of me who want a new head gasket job on a boosted truck but don't want to pull the engine? Or just chill out and use the Toyota gasket?
Click to expand...
 
I believe that is going to be the plan, it helps a lot to hear it works on your LX. I'm nowhere near that boost- yet
 
ChiTown said:
...
We need a quality (aka not Cometic) MLS gasket with a stock or thinner compressed thickness.
...
Click to expand...

Can you please expand on this thought? Are you saying Cometic isn't quality? I'd like to know as I'm running one. I'm pretty sure I'm running the 051 thick as Robbie said the slight increase in compression wouldn't make much difference here.
I did have my block and head machined to what Robbie recommended by a shop he uses in the Denver area.

Thanks man! :beer::wrench:
 
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