Headgasket and getting head machined? (1 Viewer)

[bbb18c1]

I have read through the numerous posts about headgasket replacement, and the differing opinions about doing it as PM.

Since I am the worrying type and not the rich type, I plan to do it myself soon as PM on my 95 TLC.

Nothing wrong with it right now, but at 157,000 miles, I think I better do it before it needs to be done.

My question is, is machining the head a must when doing the headgasket, or only done if it isn't within specs?

I read posts about people sending head out to be machined while doing the headgasket, but I want to check if this is necessary if I am doing it as PM and not to a motor with a blown HG.

I don't have a FSM right now, but It is on my list to get one, so I don't know what the FSM recommends.

thanks for any thought on this.

 

[mainemike]

You'll get mixed opinions... in my case, the head was within spec; the head gasket was PM at 150,000 miles (so no overheat abuse) and I did not get it milled.

Some mechanic friends felt that was a mistake, they advised me to get it milled regardless. But the shop who did it said why send out a head that is perfectly flat to be milled perfectly flat? I figure I'll save task that for the 350,000 mile rebuild.

 

[brwnj60]

Yup, depends on damage i think, it is worth the small fee to have them pressure test and check for warpage, dont want to put it all back together to find out you should have shaved it a couple thou.

 

[jamisobe]

ck it at least

 

[powderpig]

If I remember correctly, .003" is the max warp. The FSM will show you where to measure this. A true bar is the tool to use to have a true flat surface.
The places on the head I would really look at is where the sealing rings for compression are. If there is any pitting or low spots, I would have the head milled. The Toyota FSM does not reccommend Milling the head, but replacing. This has been discussed in a couple of threads.
The block is getting to be a interesting thing to me as I do more of these. It seems that the coolant has been sitting on the surface(between the gasket and the block) and etching or pitting the block to the point that the block needs to be surfaced or milled. This means that the block needs to come out and in the most drastic cases the block need to be stripped( as Ali may speak up on this if he wants). So a choice at this point is to do a full rebuild or just new rings or what is needed.
Good luck on your choices.

 

[elhombre]

Just did mine and I entered into it with the same ideas. I recommend to send the injectors off to be cleaned. Cost me $168 which included shipping both ways. My head was not warpped at all but the fire rings from the old HG left small indentions which were milled out with .007. My valve seals were toast as my car started smoking at start-up. 170K miles means tired valve seals. They are some of the last rubber pieces INSIDE the engine which should be replaced if you are there.

The unexpected thing that happened on reassembly is that the timing chain guide snapped when the tensioner was installed. It was quite brittle after that may miles. The timing chain cover had to come off so I was into the oil pan, front crank pulley, and engine being lifted to complete the job. My point is that once you get in there, things should be adressed. You can do it all as long as you stay organized. Use plastic bags to put parts in, keep a journal of each part coming off, and expect spending some extra money on parts.

Send the head out to be checked, minimum.

 

[SBFJ60FIG]

I say not necessary to send the head out...done plenty of 3VZE rebuilds, 22R(E) rebuilds/head gaskets and 1FZ-Es.

Never sent a head to a machine shop....never had to redo the job...always kept tabs on my work, i.e., sold the cars to friends, family, people that then became friends. Check it, and go from there.

However, if it doesn't cost too much wouldn't be bad to replace the stem seals! You could at least pull one out and see if it's brittle. I've pulled out Toyota rear main seals with 100k plus on them that did not leak but were about as pliable as glass!

 

[bbb18c1]

Thanks for all the input guys!

I guess I will take it apart and go from there.

Would the snap on straight edge be okay to use for checking warpage?

The 24" one?
GA438A, Straight Edge, Precision, 24"

or the 36" one?
GA535, Straight Edge, Precision, 35" (889mm)

the head is fricken long, so I don't know if the 24" will be long enough to measure the diagonal of the head.

And one more quick question: approximately how heavy is the head?
I will probably be doing it myself (everyone I know works regular hours, i'll be doing it when they are at work and I am off work), and I don't want to find out it is too heavy to lift out. I did a headgasket on a nissan 1.6 before and the head was maybe half as long, and it had some good weight to it.

Just worried that it will be awkward to lift out myself.

 

[OGBeno]

And one more quick question: approximately how heavy is the head?

If you can pick up a heavy big dog, you can pick up a 1FZ head....

IIRC, about 65-70 pounds or so...

 

[OGBeno]

( as Ali may speak up on this if he wants).

He's on the road brother....



That said, I would endorse what Robbie is saying here....

 

[IdahoDoug]

Just checked the tips on my Head Gasket DVD (blatant plug), and the straight edge must be at least 30" long to check the block for flatness. Ditto the head.

Personally, I'd take the head to a shop and have them replace the stem seals, which come in the head gasket kit that Cdan sells us here for cheap. The shop will also fully clean it for you and they can also do a valve adjustment at that time as well. To me, it's money well spent because you basically just buttoned up the engine for another 200,000 miles of reliable operation. Don't do it and it may start smoking a year from now and you'll perhaps be wishing you had spent the $150 or so on these items.

DougM

 

[cpg]

Thanks for all the input guys!

And one more quick question: approximately how heavy is the head?

Just worried that it will be awkward to lift out myself.

Without the intake attached it did not seem to weigh more than 50 pounds and was fairly easy to remove and replace solo.

 

[bbb18c1]

Which reminds me I better get myself one of the dvd's and a fsm.

what exactly is involved in replacing the stem seals?

Just checked the tips on my Head Gasket DVD (blatant plug), and the straight edge must be at least 30" long to check the block for flatness. Ditto the head.

Personally, I'd take the head to a shop and have them replace the stem seals, which come in the head gasket kit that Cdan sells us here for cheap. The shop will also fully clean it for you and they can also do a valve adjustment at that time as well. To me, it's money well spent because you basically just buttoned up the engine for another 200,000 miles of reliable operation. Don't do it and it may start smoking a year from now and you'll perhaps be wishing you had spent the $150 or so on these items.

DougM

 

[IdahoDoug]

The stem seals, or valve seals require the valves be removed. When you remove the head, there are no additional steps to remove the valves as the cams are out of the head and it's just the shims and valves left for the shop to deal with. I'm told these valve stem seals are tricky for some reason and require either a shop trick or a special tool but don't know for sure. I had them done as I wanted them done right. The nice thing with doing what I suggest is that your valves and valve seats are also cleaned and re-mated for nice tight compression and good airflow characteristics like new.

Definitely get the FSM - I think Cdan can get a good price on them.

DougM

 

[Jason YY]

I have a complete engine from a 94, with unknow service history. I purchased a 93 to drive, I have been calling around for a shop to service the head off the 94 so I could continue to drive the 93.

The first quote for me pulling the head and delivering it to the shop. They service it, make sure its within spec. $600.00

This was a phone quote, with nothing specified. As far as, what exactly they would do.

Seems spendy to me,

 

[FrankTorres]

The first quote for me pulling the head and delivering it to the shop. They service it, make sure its within spec. $600.00

Seems spendy to me,

This sounds like a price for a complete valve job with adjustment, pressure check, resurfacing, and complete cleaning.
For $600 the turn around time should be 1 day.

In my area, this job is about $500 with a 1 week turn around...

 

[91Cruizer]

I would definatly send it off to the machine shop for a inspection/ valve job. Just to check if it is flat should be only around $100. I found out my head was cracked and would have been pretty angry if I got it all together before I found that out.