2.6 Head Gasket Replacement

Gasoline-specific topics only.

Moderators: Paul, puttputtinpup, How-to Authors

Post Reply
Regular Member
Posts: 2080
Joined: Thu May 01, 2008 8:18 pm
Location: VA

2.6 Head Gasket Replacement

Post by edwright »

JoeIsuzu wrote:By popular demand, I've copied Ed's instructions here.


So you think you might have a blown head gasket.... truck runs pretty good, except you look back and see tons of white smoke coming out of the tailpipe. Open the radiator after running it for 10 seconds and it sprays out cold water all over you.

Thats only one of several ways these can blow head gaskets. Sometimes you just hear an occasional backfire because the head gasket has opened up between two cylinders.

Other times you have oil in your antifreeze

Other times you have antifreeze in your oil making for a muddy brown sludge

and lastly, you may have oil in your antifreeze, and antifreeze in your oil AND blowing white smoke out your tailpipe.

But any one of these make it pretty certain that the head gasket needs to be replaced. Theres a book way and then theres the quicker way. I've detailed it out below since I did it self taught the first time, then consulted the manual the second time.. Went back to my way on the third one.

Ok, yes, so you have the classic blown 2.6 head gasket. The thing this motor is most famous for and fortunately usually a somewhat easy fix. Plan for your truck or trooper to be down a few days, not because its that much work, but its because you have to depend on the head shop to get you in and out. Thats the hurry up and wait part.

I've done 4 of these so far and the procedure I have down pat.. I believe.

1st. take pictures of your hoses. Print the pictures and make sure you can see them. 2nd, get out the masking tape. Mark each and every hose. (a simple number will do) This one step will save you countless hours of pain and trouble. Also mark where they go. If you do nothing else I recommend.... do this step.. please.

If it has AC, take it loose and pull the compressor out of the way.

There is a mounting bracket that holds the AC.. There is a nut on this bracket that you must remove, the one that goes into the head... If, at this time you can figure out a way to get that stud out of the head, do so. I have a stud remover that works quite well in this situation and I just chase the threads out before I put it all back together. That one bolt is a pain in the rear if you dont take care of it. It take some real fun tugging to get the head off if you cant get this one stinking stud out now, and you take a chance of denting either the head or block if you dont.

Just to let you know, my method is not the book method, but I have used it successfully 4 times now and it does work.

Remove #4 spark plug. Take off the hose to the plenum and MAF, and remove the valve cover. Remove the top plastic cover on the timing belt. Bring up the timing marks and make sure cylinder 4 is at top dead center. Get out your little orange or yellow paint marker and mark both the top timing belt cog, and the timing belt cover so you can see at a glance where you need to stay to be lined up. MARK THE BELT TOO. Make note of where your half moon pin is that holds the top cog to the cam. Remove the cover to the distributor. Use your marker to mark exactly where the rotor is pointing right now. you can go ahead and remove the distributor at any time, you might wait til later after you get the plenum off to do this... but mark it now.

Remove the bolt in the cam holding the front cog on. Remove said cog and DO NOT drop the half moon pin that aligns the cam to the cog. It will fall all the way down under the main crank and if you do that you might as well just start taking off the radiator now... because it ALL has to come apart now. Just let the timing belt hang loose here.. but dont jiggle it or cram it down out of the way, work around it.

Remove all exhaust manifold bolts. Go out right now and spray them down with PBlaster... spray em again the day of or the day before you get ready to do this.

Remove all head bolts. USE THE REMOVAL PATTERN in the book!!! Make sure you use the right tool here, go buy the right metric allen wrench on a socket deal... go ahead and get the half inch version so you can use it on your torque wrench. It's a 7mm metric allen head. If you cant find the half inch, get the 3/8's version and use a 1/2 inch adapter unless for some reason you have a 3/8 torque wrench...

Remove the 6 bolts that hold the top part of the plenum to the intake. Pull the plenum up partially and mark the hoses that keep you from seperating the two pieces. Now, grab a 22 mm open ended wrench. From the passenger side, at the rear of the plenum, there is a brass hose with a large fitting. Break this loose and unscrew the brass hose. You may not find this to be the easiest task in the world.. I have since cut one of my 22 mm wrenches in half so I could get to this nut holding the hose and I use a cheater bar to turn the wrench with. Remove the upper half of the plenum. Mark and remove the ground wire on the intake. Mark and remove the temp sender wire under the bottom of the intake. Mark and remove whatever else I missed. This is a good point to drain the radiator. Open the petcock and catch the fluid or remove the bottom hose. There is a hose on the back of the plenum that must come off now and it will drain your antifreeze.

Now I do this with a lift, so that I dont damage anything and I take my time here... hook up the lift to the head and slowly start cranking it up to remove head and intake... Once you get it off, you can do bench work now

Remove the 8 nuts from the studs holding on the intake. 4 on the bottom easy to get to, 4 on the top, not so easy to get to, especially that third one from the front.

You should now be able to pull off the intake and you got nothing but head and some studs.

In order to get it to the speed shop, and or head shop, save yourself lots of money and do these steps yourself.

Take the head outside and spray it down with engine cleaner. Wash the bajeesus out of it.

If you dont have a head spring compressor, go buy one from advance, they are less than 10 bucks or so. Get the small one that grabs the spring and screws down with your hand.. that thing that screws to the valve train bolts and works like a lever is worthless on this head. Get that stud remover tool to I told you about, you are going to need it now if you dont already have one.

Now, go find a cardboard box... I always try to find a box the shape of the head.. or just close... You'll understand in a minute.

As you remove pieces to get your head ready to go... put them ON and STAB them into this box. Remove the cam bolts and remove the valve train. Lay that on top of your box. Start removing valve springs. Use a strong magnet tool to remove the small keepers. You may need to put a socket under each valve so that it doesnt slide back down in the head while you fish out the keepers. **NOTE - be VERY careful not to lose a keeper. They dont have them at NAPA, except fo fit a chevy and they dont have them at any parts store. IF you lose one, forget trying to even look for it.. When you lose it under spring power it rocketed off so far you will never find it... Your only remedy now is to go to the junkyard and start pulling a valve cover just for ONE LITTLE KEEPER. Remove the wear washers under the valve springs.. throw all that in a bag. As you remove each valve, stab it into the box into exactly the same place you got it OUT of the head from. Mark the box front and rear with a marker. If it needs cleaning now, go wash it some more. The cleaner it is, the less they will charge you for cleaning labor... Remove ALL the studs from the head and stab them into the box too. **Note, the studs are slick and it takes a little trick to get them . Grab a pair of vice grips and set them pretty tight, and clamp them once in the clear part of the stud to make little ridges in it for the stud remover to grab ahold of... THEN use the stud remover on them and it will grab fine. Remove the valve seals, and check them for squishiness... if they are pliable.. reuse them. If you really feel the need to replace them now, please do so. but know the difference between a head set and head gasket and intake set are about a hundred bucks. Low budget - reuse the valve seals if they are ok, and reuse the exhaust gasket.

You should now be ready to go to the head shop. Ask them to mill it and check it for leaks. Dont let them out of the "check it for leaks part" These heads are notorious for cracking. The price I have been paying is $175.

Now, what I use to prep the block, is to use what I call a "whiz wheel". Please dont gouge up your head with a wood chisel or a screwdriver... Pull out the alignment pins now with a pair of needle nose pliers and put them in a ziploc bag and mark the bag. The whiz wheel is the little round thing you stick in a drill or air grinder that looks like its got a very gritty piece of sponge on it. I use the small 1 1/2 inch ones. Clean the top block surface and polish it, remove any carbon deposits from the tops of your pistons now, and follow up with first a stainless cup brush on a drill, then a brass brush on a drill and really polish the top of the block. Keep everything clean as a pin, very important. Use a straight edge and check the top of the block, to make sure you dont have warpage. look real close with bright light to watch out for pitting. If the pitting is too bad we got a problem... you may need to pull the block here and go for a whole rebuild... It's doubtful but please study this good before you put any more time and money into it.

Now that you have the head back from the head shop, I use the copper spray gasket and spray the block down with a good, good thick coat. put on the head gasket and stop for now. (put your alignment pins back in now too)

Now, put all the head parts back on the head including plenum and intake. Now that you have everything marked, everything will go back together very nicely now. Use your stud remover and torque down the valve train studs and might as well torque the intake studs too. Put your springs and valves together. put the valve train back together and be sure to put in some gasket sealer on that little half moon seal on the back of the head. Valve springs go blue end down. When you put the intake back on the head MAKE SURE YOU PUT THE INTAKE GASKET WITH THE WATER OUTLET SEAL ON THE RIGHT SIDE. I'll be happy if nobody asks me why I say that, or why I put it in caps... Its just a very good thing to check right now ok?

Now, grab your lift again and line up the head and get ready to start dropping things back together. optional: I spray the top of the head gasket now again with the copper spray, just to make sure it seals... I do it wet, so that if there is flow needed, it flows into any gaps now.

Be VERY careful when you lower the head. If you oops and drop it, you will cut the head gasket in half and ruin it. It's too heavy to try by yourself without a lift.. If you dont have a lift, get a buddy to help you slowly drop it down and line it up.

Start hooking everything up.. and be thankful that you marked EVERYTHING. Button everything up including the exhaust manifold. I use a little copper spray here too.

Once you get to the top cog for the cam, remember where it was when you start this. Put the cog back to the same position it was when you started. you should be able to hold the cog up to the cam and line everything up manually right now.

Now, when you put the cog back on, you might be lucky enough to be able to strong arm it back onto the cog and get the timing belt back on there. but if not, you need to use a pry bar and push the tensioner to give you a little slack. (SEE THE ATTACHMENT.. you can take loose the top two bolts and the plastic cover will allow you to get a wrench down in there to loosen bolt B. Make sure all marks line up and then button everything else back up... TIGHTEN bolt B. replace timing belt cover and oh.. um I forgot way back there somewhere.. that last stud that holds the AC? NOW is the time to put the stud back in, THROUGH the AC bracket. You wont be able to torque it down, but thats not really important in my opinion, its just a bracket. tighten the bolt on it right and it willl be turned into head far enough it doesnt matter. But just get the stud in as far as it will go before putting on the last nut.

Add your antifreeze now.

Okay, I think thats it. Cross your fingers, crank her up and hope for the best...

Here are lots of nice helpful pictures for you.

edit: The allen metric is not a 7 mm like I listed above... I actually ended up using a T55, which is a torx bit, but you should get your metric wrenches and make sure you know what size Allen Socket you should buy. I would have done it tonight but I got busy and forgot to do it... besides It's temporarily dissapeared somewhere in my shop... :lol:
Torque Specs.gif
Torque Specs.gif (2.86 KiB) Viewed 20348 times
head tightening sequence.gif
head tightening sequence.gif (7.95 KiB) Viewed 20346 times
head removal sequence.gif
head removal sequence.gif (8.01 KiB) Viewed 20349 times
camtensioner.gif (6.26 KiB) Viewed 20352 times
Last edited by edwright on Thu Jan 29, 2009 8:55 pm, edited 4 times in total.
1986 Trooper Turbo Diesel LS Red
1986 Trooper Turbo Diesel White
1986 Trooper Turbo Diesel LS Blue

"If by "drag machine" you mean a little truck to transport cross dressers then it should work out just fabulous" VeggieNate
User avatar
Regular Member
Posts: 239
Joined: Wed Mar 05, 2008 7:36 pm
Location: Atlanta, GA

Re: 2.6 Head Gasket Replacement

Post by dunkel »

Awesome, thanks.

Hope I never need to use this info, but I'm glad it's available if I ever do.
'88 Pickup 4wd Standard Cab 2.6 Gasser 2" suspension lift
Official member of Jeep Recovery Team
Post Reply