Headgasket thread (1 Viewer)

[grant5127]

What frustrates me is that he acknowledged that he didn't check over his mechanic's work-

Checking over someones work on something like this would be standing over a body watching the whole process...

That would be time consuming as hell! Supervisor might as well do the the work himself....

These thing aren't rocket science you know, the Japs just copied the old Chevy....

Competent people are hard to find....

 

[taro]

The shop owner has done several restorations. He is the one with the fj experience. The guy who replaced the hg is one of the younger guys...

 

[taro]

What I meant by check over is at least check the compression after the work was finished. I would have liked for the valve clearances to be double checked before the valve cover was replaced also :/

 

[Pighead]

You'll be wanting to do your own valve adjustments after the HG and the re-torquings anyway...no need to take up your mechanics valuable time and you can do a more careful job of it.

 

[Fuzzy Logic]

The guy who replaced the hg is one of the younger guys...

BINGO!

 

[Fuzzy Logic]

You'll be wanting to do your own valve adjustments after the HG and the re-torquings anyway...no need to take up your mechanics valuable time and you can do a more careful job of it.

You gotta be kidding, are you really serious?

 

[taro]

You'll be wanting to do your own valve adjustments after the HG and the re-torquings anyway...no need to take up your mechanics valuable time and you can do a more careful job of it.

Actually, before I lost my garage, this is something I would want to do. Trying to do a tune-up on my motorcycle today sucked. I took off the fairings and gas tank, drained the coolant and oil, spilled the oil as I was trying to dump the oil in my oil container, then had to take my son to baseball practice, so I had to put all my tools away, put the fairings, etc. somewhat back together, come back, coolant tube bolt is stripped and therefore can't get the valve cover off and therefore ended up just changing the oil and coolant and putting it back together :-/

 

[bsevans]

It has already been mentioned a couple of times, but I feel you need to understand the impact of not chasing the threads in the block. When you run a tap you will be amazed at the resistant rust and crude have on the process. I also recommend that you use ARP Ultra Torque Assembly Lubricant. It has been proven to be the best method of achieving true bolt torque. Excessive resistance at the thread contact zone between the head bolt and the threads in the block reduce the compression between the head and the block which means the head gasket is not compressed enough to form the expected seal. The head gasket only goes on one way. When installed properly, the rear oil passage is aligned and the excess head gasket sticks out the back of the head not the front.
The M13x1.75 tap is off the shelf at MSC Direct Metric Taps for $25.61. It is listed on page 293.

 

[taro]

bsevans, thanks for the explanation. I'm always wanting to learn new things.

I spoke to the mechanic this morning who said that the threads were chased and that the bolts were tightened with a new torque wrench. He added that the bolts were at the correct torque specs when they began removing the head this last time. Thoughts? Thanks, Taro

Ps-hg should arrive tomorrow or Wednesday.

 

[grant5127]

He added that the bolts were at the correct torque specs when they began removing the head this last time.

And that was what ft·lbf # ?

 

[two10wagon]

This may sound crazy, but are you sure it was the gasket that failed??? Did you magnaflux the head and have it cleaned??? Your head may actually be cracked. If its not and the mechanic is being truthful....either the block isn't milled flat or the head is warped.

 

[taro]

grant5127, I'm not sure what figure he used.

two10wagon, I forgot that I posted that information in another thread. The head was machined by another shop when they fixed the hg the first time. When it blew, they sent if off to the same shop to have the head magnafluxed and no cracks were found.

 

[Pighead]

He added that the bolts were at the correct torque specs when they began removing the head this last time. Thoughts?

Well, I almost always (I have blown one or two) re-torque my headbolts...a lot, before I run it hard. And I'm used to getting a good quarter-turn out of each headbolt the first couple times.
And I'm not sure how your mechanic knew the torque of the bolts he unbolted...
Did he re-torque after the fact or break them loose with the torquewrench?
This should be really easy. Gazillions of LandCruiser headgaskets have been changed successfully. If your block and head are indeed straight, it should work just fine.
It's just cast iron, we can out-think it.
I know you will insist upon spotless preparation this time. And numerous re-torques, as it should be.

 

[grant5127]

Hey taro... when you wake up check this one out I pulled out yesterday....

Its made by http://www.google.com/url?sa=t&rct=...ezqYw5&usg=AFQjCNF8RXqFRU1WapOQ63STh7v7g9Hm1w it is a safety gasket, asbestos free ( I feel better now knowing my mesothelioma risk has been reduced).....

Anyway, it lasted for 16k miles and 13 months.....
That ended up being 4k miles and 1 month out of warranty.....

Just FYI, entertainment purposes only & a bump for your thread....

HAVE NICE DAY....

 

[taro]

Pighead, I'm assuming that he re-torqued the bolts because that was the first thing he was wondering about when the gasket blew. Re: prep and re-torquing, yes of course

grant5127, thanks for posting up the image--misery loves company That's where mine blew x2 now--between #3 and #4. Did #5 get damaged during removal or was it 5 that went and the area between 3 and 4 that got damaged during removal, or both, or...

Also, I'm assuming that a warranty on a gasket is kinda worthless relatively speaking, no? I mean even if it were covered under warranty, they are not going to cover the labor are they?

Thanks, Taro

 

[taro]

grant5127, you got me curious, what happened? Inquiring minds want to know!

 

[grant5127]

Permatorque...

Truth came out: road hard and put up wet,(melt down) to say the least...

# 5 blew to the outside and 3 & 4 swapping compression was just the start.. crack between valves on #2 and deck warped......

Donor located.... going to try this new Felpro gasket... I really like the looks of it, has a strange texture and a somewhat tacky feel....

Bummer, instruction state use no adhesive as I was planning on a good dose of copper coat for extra insurance as the block deck doesn't look all that great... can't do anything about that because the situation funds have dried up....

We shall see..........

 

[xtremitys]

If u want get anal bout things , i am aware of engine blueprinting shall we say , torque wrenchs arent that accurate as u may think , theres other ways that are more accurate , they dont indicate load on thread , but bolt stretch as the head rebounds when its tighten . Othr ways too ( degree gauge ).
& it pays to sequence the bolts down in min 3 stages . Some head gaskets i wouldnt retighten as they can only be torqued once , then buy new one . If have.probs with felprobe one , give felpro a phonecall ir ask how to torque that model hq .

Also if u have problems with sealing ,have the tops sleeves/block machined for O or W rings & run a full copper head gasket ,most performace diesels builders do that .

 

[MicahMan]

Just read the thread sorry about the headaches. Same sort of issue on my carb. The "Youg Guy" got a shot at it.

Good luck with the HG from what everyone says they seem to work well for everyone here.

 

[taro]

grant5127, good luck on it. Please keep us updated.

xtremitys, thanks for the info. I am still waiting for the hg to show up

MicahMan, sorry about your carb issues. We'll get this stuff straightened out eventually ...