Fixing the Heads

So in last weeks episode you may recall we broke a couple of studs in the heads and we were really hoping to not have to pull the heads to fix/get them out. Well, while that might have been nice for us, it wouldn't give us this great opportunity to generate more content. So as you may have guessed, that is what we're doing this week.

 

 

The next day I spend a couple of hours with a Milwuakee drill basically doing more harm than good and I finally gave up and decided we should "generate some blog content".

Removal

First pull the valve cover- This was especially easy since we were into the engine a bit already (see last post), also I did this before I knew we were going to pull the heads because I wanted to size up the situation. That's why there are no pictures, but if you're having trouble at this step you may not want to proceed anyway. You will need to pull the plugs and the three temp sensors (or at least disconnect them, along the drivers side). And you just as well pull the thermostat housing on the passenger side, since you'll need to access the timing chain tensioner anyway).

Big picture to remove you need to pull 14 large bolts along the over head cam and four baby bolts up front (including the one the holds the dizzy in place).

From the "diagram" above, you can see 1 and 2 are easy- 3 isn't too hard, for 4 you have to make a leap of faith of sorts since that cavity will probably be full of oil. So just feel around with your allen wrench and plan on doing that one by feel. 

Those 4 can be a bit snug so be prepared.

The timing chain can be a bit of a pill to have to work around as well. Undo the bolt which retains it- loosen the tensioner (see photo below) and hit it with a rubber mallet.

 

 

You may need to fenagle things a bit from here, but you should be free- there are  a few posts however that keep the head in place so you will need to lift directly off.

 

From here, you can replace head gasket, rebuild top end, mill out busted bolts. My head gasket appeared OK( you still need to replace it). Wes strongly urged me to rebuild the topend, but since the motor was fine, and I want to get home some day before X-mas I declined- we're just going to get the bolts out.

Milling Out Busted Bolts

If you're buddy doesn't have a drill press, lucky you- this step is easy just take the head to a machine shop and pick it up when it's done. Wes has one though so here we are. 

 

We had two studs that were broke off below the face, so none of the other tricks would work. (by other tricks, I mean welding a bolt head on, using an easy out or anything else as much as I love "well, actually...." comments, please know- we tried.

To the mill, we start small, use lots of cutting oil, and slowly work our way up.

Finally we use an endmill bit to fully drill out the hole.

 And then wetap new M10x1.5 holes.

And "just like that" (lol, it took a day or so) the head is done. 

Reinstall the head

maybe drop front bolt 4 into place before settting it- we lost it an an hour removing tensioner to fish it out

Cleaning up

So the first thing we didn't do was clean off the top of the block with an angle grinder but don't  let us stop you.

 

What we actually used was razor blades and scotch brite pads.

 

And chemicals.  Lots of brake cleaner. And we also lapped the bottom of the valves.

Getting close now, we set the head gasket.

Here we see the spec sheet that came with OUR head gasket. Don't go off of this unless you have an M130.929 engine. Use the sheet that comes with your head gasket, or for God's sake- get a Hayes Manual (ours showed up the day after we finished this project). 

Also you'll want to re lube everything with assemblers grease. And torque down the head bolts to the spec listed. A freindly note on those front bolts, you might want to set 4 in the head before you put the head on- we spend an afternoon trying to fish it out- if you lose one, pro-tip, pull the tensioner out and you can get it much easier.

And in just a few short days you'll be back to where you started except with fixed heads. Moral of the story- when you pull those studs, use lots of penetrating oil and take your time.