new head gasket

[87quest']

i need to change the head gasket in my 87 conquest i was wondering what i all need to take off...got it off but maybe its a cracked block...read my last post Edited October 28, 2009 by 87quest'

[newquest86]

you set up the engine at top dead center first turn the engine clockwise only ! from the crank bolt if you didnt download the factory service manual from the faqs section go get it and read it and follow it carefully its easier to remove and install it with the exhaust manifold and intake manifolds on it install the intake manifold and gasket on the head before you install it ! the exhaust doesnt matter install after is ok and easy you can do this without removing the timing cover provided the cam gear shelf is there to rest the cam gear on when you remove the rocker cover line up the timing marks remove the cam gear and set it on the shelf under it look in the fsm it shows you this step if its not there like my engine you gotta remove the timing cover ! and dont just change the head gasket without checking the head to see if it is warped the specs are only .002 thousands if it is warped more than that it will only blow again and you should buy new head bolts use a good felpro gasket too . while it is off you should change the heater hoses from heater core to the intake

[BrokenquestTSI]

if you just start disconnecting stuff, its all really self explanatory. Everything that connects to the manis pretty much.

 

And make sure the heads not cracked either man.

Edited October 26, 2009 by BrokenquestTSI

[vbrad511]

Like has been said, leave the intake and exhaust on it. It'll be heavier, but well worth it. Felpro, either 8770 or 9116(the later model gasket), and absolutely retorque the head bolts after a couple heating/cooling cycles, and no boost until you do. Our head bolts are not torque to yield, so you don't need new ones, but ARP studs are always nice.

And drain off a fair amount of your antifreeze. It'll save you from a big mess on the floor.

[87quest']

i already have the intake and exaughst manifolds off and im able to pull both of them off of the studs so that should clear. i was just wondering if i had to take the timing chain cover off to adjust the timing gear and im pretty sure you do i just wanted to make sure that there wasnt an eaiser way. another problem is that my engine was not at TDC when i did this how big of a proble is this?

[Indiana]

You just put a socket on the crank pulley bolt and turn it over. Go clockwise until the dowel pin in the cam gear is at the top that lines up the notch on the crank pulley to the T mark on the timing cover. Will turn easy with the spark plugs out maybe by hand. Does this motor have balance shafts still? Be a good time to adjust the guide. There are some things be aware of after you get the head off. The bolt holes can't have oil or coolant in them, both surfaces must be completely clean and you need to inspect the head to see if its cracked.

[mikec]

You don't have to remove the timing chain case cover to do the cyl head gasket. When you remove the valve cover, and the half-moon shaped rubber bit at the front of the cyl head, you'll be able to remove the bolt holding the timing chain sprocket to the camshaft. Take the bolt out (may need an impact gun) and then pull the sprocket off the camshaft. There is supposed to be a little metal shelf bolted to the engine block just below the sprocket... the sprocket will get pulled by the timing chain tensioner onto this shelf. It'll sit there as you lift the cyl head over the chain + sprocket.

 

Ideally you'd have rotated the crankshaft pully/sprocket to put the engine at #1 cyl top dead center before starting the job. But if you didn't, don't worry. Just don't let slack get into the timing chain while the sprocket sits on that shelf. When re-installing, you'll have to line up the camshaft to the sprocket. THEN turn the engine to #1 cyl top dead center. The index pin (roll/shear pin) that connects the sprocket, camshaft, and that stubby shaft going to the distributor, will be pretty much at 12 o'clock when the engine is at #1 top dead center. Now you can install the distributor, adjusting how it meshes with the drive gear, so that the distributor rotor lines up with the #1 spark plug wire on the distributor cap. You may have to remove/install the distributor a few times to get this right... when correct, the stud poking out from the cyl head will be pretty close to centered in the banana shaped slot on the distributor. Finish assembling the engine, start it, and let it warm up a bit. Use a timing light to fine-tune the ignition timing to 10 deg BTDC. I posted details on setting the timing recently in a thread started by killtodie.

 

When removing the cyl head, you need to back out the cyl head bolts a little bit each, in a specific sequence, to minimize stresses on the cyl head... otherwise the head can be warped. The factory service manual shows the details - and you can download a PDF version of the whole thing from several sites. You'll also see two small 10mm headed bolts in the timing chain "hole" at the front of the cyl head; these connect the cyl head to the timing case cover so they have to be removed as well. With the cyl head off, I STRONGLY recommend taking it to a machine shop and letting them check it. I'll bet it isn't flat any more and will need to be surfaced. Otherwise it won't seal properly to that new head gasket. Typically the exhaust valve guides will be worn too. You can check the block for flatness - get a good straight edge and some feeler gauges. The factory service manual shows you how. The manual will also show you the proper head bolt tightening sequence.

 

As for the vac hoses and all that "stuff" that's gotta come out to remove the cyl heads: it's not as bad as it looks. If you examine the vac hoses carefully, you'll see most of them go from the injection mixer assembly to the intake manifold - which you'll be removing as one big piece so you don't need to undo those hoses.

 

mike c.

[87quest']

ok well i have the head off and the gasket looks fine....no good. there is oil on my fire wall soo does this mean a cracked block? also oil and antifreeze in the cylindars

[Indiana]

Oil and coolant ran into the cylinders and bolt holes when you pulled the head off all you have to do is wipe it up. You can't have any oil or coolant in the bolt holes or when you put the bolt back in two things happen, one that liquid partially may come out and contaminate the gasket and the block/head surfaces and the other is that if there is enough liquid in there the bolt seals on the threads and you can build up hydraulic pressure that gives false torque reading and if you tighten enough you can cause cracks in the block. You'll have to use a small brush and some solvent or cleaner on the head in between the intake and exhaust valves and look for a hairline crack. A crack leaks coolant or will eventually so if a crack is there don't put that head back on. The block and head must be 100% cleaned of all old gasket material. The torque sequence tightens the middle of the head first and moves out to each end, its so the surfaces don't cause the gasket to slip. You've pushed something across a loose carpet before, how it can roll up in front of you from the pressure and in front of you there isn't any? That's why you start in the middle and work outward so that isn't happening, its the opposite for removal. Just wipe oil on the bolt threads when you reassemble, if oil is dripping it can contaminate the gasket when you put the bolt in, as you tighten it down and the head is just laying there as the threads go down the oil is wiped off and it just oozes right under the headgasket and you might as well take it all back off and start over. I don't know what others use to clean the block and head surfaces when they don't have air tools its been along time since I had to do that by hand but its very important that all the old material be removed and all you see is bare metal.

 

The issue of a warped head you can check with a straight edge or have a shop do that for you and the same is true for the block. If its a block that appears to have never been out or been milled down you can bet its low in the middle and may not seal a gasket well enough for anything more than stock boost. Even then it may not. Its up to you to check this.

 

You could also get coolant in the oil from the intake manifold and the throttlebody gaskets.