what the hell is the big deal! (for those wrenchers) (1 Viewer)

[Riley]

Rick, funny you should bring this up. As I read all these HG paranoia threads, I've been thinking about doing mine as PM.

Problem is that I'm not sure I trust myself. I have actually considered planning a family vacation to Golden CO area and have Robbie replace it. It's going to need to be done at some point.

 

[Junk]

How about with the hood off? Cant remember if the back of the head tucks under the firewall or not.

Guess you didn't read all the posts in this thread did you?

 

[Lars]

Guess you didn't read all the posts in this thread did you?

is right.

 

[landtank]

Personally I'd put setting the preload on a set of wheel bearings higher than anything on a HG replacement.

Dan so nicely eluded to the fact that I broke a timing guide. Yes that happened and it did open a can of worms for me. I had scheduled a weeks vacation and got the job done within that time frame.

Admittedly I was apprehensive when I got started but the job was really quite easy. Your basic unbolt, clean and reassemble.

I've been contacted about working with another forum member on a HG job and putting out a DVD on it. I think I should do this.

 

[LoveTractor]

I've been contacted about working with another forum member on a HG job and putting out a DVD on it. I think I should do this.

What's your address? I'll send you my order and money right now.

 

[tucker74]

Problem is that I'm not sure I trust myself.

It's really not any harder than an F or 2F other than all the accessories - the hardest part IMO was separating the intake manifold (fawking bottom bolts) ... which a lot of guys do to replace the silly valve under there. You can do this -

Tucker

<-- Looky there - I'm officially and addict ... err, sort of I guess

 

[whodat]

I've been contacted about working with another forum member on a HG job and putting out a DVD on it. I think I should do this.

More 80 porn, me likes.
wd

 

[Cobra Jet]

I personally do not see why it's such a huge deal to change a head gasket...

Sure, if it's a daily driver and your ONLY vehicle and you don't have the desire, skills, drive, tools (or lack of) to do it, then definitely take it to a mechanic. Any such R&R as this, one SHOULD HAVE an original Shop Manual on hand, not a Haynes and not just relying on internet tech - this way you can follow all steps exactly as outlined in the book. If following a shop manual, there really should not be any questions because it's like assembling or disassembling any other piece of equipment by the book - only on a larger scale.

I've replaced head gaskets before on Mustangs - which of course are quite different in design and much easier to replace over any European or Asian product. However, just this past weekend, a friend and I removed the head off of his BMW 535i because it blew a head gasket... Removing that BMW head is really no different than removing a Toyota LC head - sure, there are a lot of things to remove, throttle cables, wire harnesses, intakes, air box assembly, exhaust manifolds, sensors, cam sprocket, timing chain, etc.... I mean, the job is not "hard" per se, but, it IS time consuming. If one does NOT have the time, I would never recommend such a job for an "amateur" wrencher, or one who has NEVER removed any piece off the top side of an engine...

The BEST advice I can offer for first timers for this type of job is this:

1) EXPECT to run into issues - regardless of when you start the job

2) Have original shop manual on hand (regardless of vehicle)

3) Have all of the proper tools needed to do the job BEFORE you decide to take things apart

4) Have all of the proper replacement parts, gaskets, bolts, nuts, fluids, etc to do the job BEFORE you decide to take things apart

5) Get yourself a box of ZipLoc baggies and a Sharpie marker. When you remove certain nuts/bolts insert those into a single bag and LABEL it. The same holds true for when removing small parts, put the parts into separate baggies and LABEL THEM. This way, when it's time to reassemble, you will know EXACTLY what those parts are for and WHERE they need to go when putting everything back together. Even if following a Shop Manual, do this, because it will greatly aid you in the reassembly process and avoid lost/damaged pieces and parts.

6) Check things TWICE before reinstalling - torque specs, proper bolts going to the proper parts (that's when labeled baggies help!), fluid capacities, timing marks, etc

I've had multiple engines apart, installed exhausts, installed many aftermarket parts, replaced gear sets, converted drum brakes to discs, etc... I mean, sure, I'm not the "average" weekend garage mechanic, as I do have many years experience (and different apttitudes/knowledge due to the number of vehicles owned), but I DO KNOW what I am doing when it comes to mechanical issues...

Replacing a HG on a Toyota is no different than replacing it on any other vehicle - the only differences being how the parts come off and the number of parts having to be removed (or moved out of the way). After the head is off - it's all the same as far as repair and/or replacing the gasket...

Like I said, having the original Shop Manual on hand and the proper tools - ANYTHING can be done by a non-certified mechanic, trust me. It only takes time and patience - if one lacks either, then trying to tackle a job such as a head gasket replacement can be quite an experience in itself.

If a HG blows and one does not drive miles and miles KNOWING they have a blown headgasket - meaning, if the HG blows and you immediately shut down the vehicle (preventing extreme overheating), then all that is really needed is a gasket replacement. IF one drives for miles on end with white smoke billowing out of the back of the vehicle, sure, the job is no longer just replacing the HG. Driving distance after blowing a HG is definitely a "no-no", especially if the temp gauge sky rockets, is only overheating the vehicle which will cause MORE damages to other surrounding components...

Eh, maybe the above was helpful to some, but for those of you who are mechanically inclined such as myself, it's just a matter of taking precautions, knowing WHY your vehicle is reacting or acting the way it is beyond the "norm" and having the time to replace such parts.

 

[Rainy Day FZJ]

I did mine as a PM and it was not really a big deal at all, I figured out some short cuts. Like when seperating the intakes and leaving the wiring harness in the upper half, just slide the intake up onto the passenger side and use a bunge chord to hold it. Use 3 zipties to hold the timing gear and chain together, keeping it in time. Place a piece of cardboard in back of the radiator to protect it from bumps and scrapes. I used the baggie method and it worked for me. I also used 2-12 packs of egg crates to hold the valve tappets well labled, and check the clearance after reassembly to compare before and after that should be exactly the same. Use 2 people to lift the head off is a must if you don't want to break the chain guides. I borrowed a great torque wrench as a must have. Leave the down pipe for the exhaust connected to the cats and just remove the bolts that hold the hangers to the frame to give that needed little slack in the exhaust to remove the manifolds. Have the injectors cleaned as you are taking the rest of the head apart. Just do it if you can, it really is not hard compared to other HG that I have done. Think of it as a really expensive puzzle that you take apart and reassemble in the same d@mn order......

 

[Gumby]

You didn't replace the timing chain when you had the head off? I could see if it were an emergency and you had to get it done, or it was a premature HG failure, but you did the HG as a PM and didn't replace the timing chain?

 

[cary]

This discussion reminds me of how complicated things have become. I could pull the head on my dad's 20r Toyota truck in about 20 minutes, and put it back on in about 45. Had to do it twice because the machine shop didn't find the warp the first time.

 

[cruiserdan]

You didn't replace the timing chain when you had the head off? I could see if it were an emergency and you had to get it done, or it was a premature HG failure, but you did the HG as a PM and didn't replace the timing chain?

You have to lift the engine up off the front mounts and pull the oil pans in order to get the timimg cover off.......

 

[semlin]

can you fix the famous chain slip tensioner thingy doodad with the head off if it is broken, or do you have to lift the motor off the mounts? Should you have that part handy in advance?

 

[cruiserdan]

The timing cover has to come off to do it. I replaced mine when I had the front of the motor apart. It looked OK but it was only one bolt away from comming out because of the other work I was doing and I was not about to leave to there.

 

[Gumby]

You have to lift the engine up off the front mounts and pull the oil pans in order to get the timimg cover off.......

Where do you stop? Do you just pull the head and slap it back on? Do you figure a couple of weeks for machine work and injector cleaning?

I would have a very hard time not doing a bunch of stuff while I was in there.

 

[cruiserdan]

That's exactly right. I tend to suffer from "While it's apart" and things get way out of hand. I think that if you intended to take both the top and the bottom off you would be better off pulling the engine and since it's out of the frame with the top and bottom off you might as well ring it and replace the bearings and then you might as well.......... never mind......

 

[Gumby]

Exactly, I'd be out of a couple of grand in a big hurry.

 

[semlin]

why not throw in a diesel and a 5 speed whiile you are in there?

 

[landtank]

If I had an engine that had the old stile tensioner than I'd do that as well especially with an upper arch seal leak.

These engines where designed for something like 300k per rebuild. If your somewhere around 130k why stress over all that "while I'm in there crap'. You replace the 1 item that will likely be the cause of your first engine problem and then drive the thing comfortably for the next 170k. We could be talking another 10 years or so, you could be dead or the truck stolen, crashed or what ever in that length of time.


$175.00 for another 10 years of solid performance, THAT'S a bargain!

 

[Gumby]

Just got back from the machine shop. More to think about when thinking about a headgasket PM

The MINIMUM machine work necessary for a head gasket job

List prices

78 2F head. A magnaflux would not work on a 1FZ, you would want a pressure test instead.

Clean 31.50
Magnaflux 24.50
Resurface 59.50
toxic waste surcharge 10.50

Took 2 days at the machine shop.

i will do the valves myself. On a good running 80, maybe I wouldn't take out the valves, but that would be a hard choice to make assuming the motor has 100,000 miles on it. I would be sorely tempted to swap out the oil seals and lap the valves at least.

Head gasket - $160
Valve stem seals - $9 each (for a 2F, dunno about a 1FZ, gotta hope it's less for 24 valves)
intake gaskets
exhaust gaskets
v/c gasket
t-body gasket

To be fair, the valve grind kit was much cheaper than the parts. About $200.

don't forget 2 gallons of antifreeze and 8 quarts of oil
you'll need a couple cans of carb clean while your intake is out

If, and it's a big if, everything goes OK, I can't see it being done for less than $400.