Im about to replace HG any tips?

[flyjum]

Any tips on replacing the HG? Do i need to take the engine out or what? Also what is the factory torqe spec and what do you recomend for the headbolts? Also what is a common area for cracking in the head I heard they crack alot? HG should be here tomarrow.

[SoobGoob]

they crack between the valves on the heads, ignore it unless its really bad. i think GD said tourq all of the bolts to 20 then 35 then 50. you dont have to take out the engine to do it but you will by bending over and laying down for a while

[idosubaru]

EA82's are a cake walk to replace headgaskets on. the turbo is the most annoying part of the whole deal. all that freaking piping and rusty bolts in the way.

 

if you have air tools, removing the engine is a complete waste of time. leave it in the car and go to town. i never remove them for just a head gasket job, even on the larger XT6 engine. but if you only had hand tools to work with they are much nicer to work on out of the car. if time is critical then leave it in the car you can have it done quicker if that's how you want to work.

 

clean all the bolt threads and holes (this is where air tools are super nice). i personally have all the valve seat cracks repaired at the shop. they use stitch pins specifically made for this (info already posted elsewhere). have the heads milled. the cam carrier o-ring is a metal reinforced joker, it must be bought from Subaru or http://www.thepartsbin.com, i haven't seen them sold anywhere else. make sure you don't use just a regular o-ring for it and make sure you replace it. you'll need some thick grease for hanging the rocker arms in place while you install the cam carrier if you're doing it with the engine in the car. be careful with intake manifold bolts, they like to seize and shear off. that's no fun.

[kayakertom]

First time: have a newspaper covered flat surface ready to put your removed parts on with several small containers for the fastners - keep the fastners with the parts you remove grouped together. Have a cleaning station set up - large shallow container with "Simple Green" or other grease dissolver, wire brush (small), old toothbrush, paintbrush and plenty of rags. Large mouth, shallow container to collect your coolant, funnel and another gallon container.

You will also need an rtv sealant for the cam tower

 

Tools needed: 10, 12, 14, 17 mm combo wrenches, metric socket set - deep ones are useful in several areas, breaker bar with 17mm and 22mm sockets, torque wrench, phillips and regular screwdriver, adjustable wrench, safety razer blade for scraping off old head gasket material, some fine wet/dry sandpaper, magnetic pick-up tool, mechanics mirror, grease for when you reinstall the lifters and rocker arms - holds the rockers from falling.

 

The head bolts have a tightening sequence that you should follow.

 

You should also replace the intake manifold gasket.

 

Rotate the engine until the center of the three marks on the flywheel is at the pointer.

 

Take your time and have fun. Don't curse too much if you are doing the drivers side and go to take the clutch fan off.

[PonchoCatalina]

A tip about removing that clutch fan: there are a couple of flats on the shaft IIRC that allows you to hold the fan still while turning out the four bolts that hold the fan to the shaft. It took me a while to figure that one out.

 

Another tip: don't worry about unhooking much if anything from the intake manifold. I had planned to unbolt mine and set it in the spare tire rack (don't know if you have one of those on an XT?), but discovered I'd have to undo fuel lines, etc. to even move it that far (this is on a 91 Loyale). It was sort of entwined with the A/C hoses. I simply unbolted it from the heads and left it where it sat and chocked it up with a couple of blocks to keep it out of my way.

 

Final tip (for now): My cam cases and heads were really difficult to break loose after removal of all bolts, despite whacking them with a rubber mallet and the like. Obviously, you don't want to pry between these things, so I finally braced a 2x2 about two feet long against the back of any protrusion I could find on the respective cases or heads and drove them loose by hammering on the end of the 2x2. For example, on the driver's cam case, I braced against the back of the distributor mounting point (disty already removed). Same with the heads: they have a little "corner" on them that sticks out that you can rest the end of 2x2 behind. Worked well and caused no damage - just make sure *all* bolts are out first.

 

- Ian

[nipper]

Work as clean as possible. If your doing a valve job make sure everything goes back from where it came from. Work clean. If you have a digital camera use it to take pics of connections and hoses and anything else. Work clean.

If you have to ask us for the torque specs, you dont have a manual, so get one firts then read up on doing the job.

 

nipper

[revbill]

If you can, I would have the heads pressure tested or pull the valves and check for cracks that extend into the ports. Especially if the gaskets look OK. It would suck to do all that work and have it turn out that one of the heads was cracked (ask me how I know this.)

 

The cracks between valves are very common, and usually not a problem, but there's really no way to tell unless you pressure test or inspect them. From what I have read, and my recent experience with my Loyale, the passenger side is more likey to crack in a bad way.

 

Other than that, just follow all the instructions carefully, and come here for advice when you need it. I've found everything I needed to know about my car by searching/browsing here, and people here are as helpful as they come.

[Ross]

Clean the mating surfaces of the head/block well, but dont sand it down to a smooth surface.... HGs hold a bit better with a rough(ish!!) surface...

[nipper]

Clean the mating surfaces of the head/block well, but dont sand it down to a smooth surface.... HGs hold a bit better with a rough(ish!!) surface...

 

NNONONONO

 

this should be machine smooth, no scratches. Scrtaches are extreemly bad. They make leak paths. this is bad bad idea.

 

nipper

[kayakertom]

Another thing: When you drop the exhaust manifold, put some plastic bags over the two manifold openings to avoid getting coolant down the pipes when the cylinder head is removed.

[ryry46d9]

Another thing: When you drop the exhaust manifold, put some plastic bags over the two manifold openings to avoid getting coolant down the pipes when the cylinder head is removed.

 

GOOD IDEA

:clap: :clap: :clap:

[Ross]

NNONONONO

 

this should be machine smooth, no scratches. Scrtaches are extreemly bad. They make leak paths. this is bad bad idea.

 

nipper

 

Machine smooth.... well, sort of..... smooth.... NOOO!!! If you've ever seen a freshly machined head/block you will notice that it is relatively rough to touch. Cleaning the surfaces down to a near mirror surface will almost certainly result in a HG with a short life.

[GeneralDisorder]

Machine smooth.... well, sort of..... smooth.... NOOO!!! If you've ever seen a freshly machined head/block you will notice that it is relatively rough to touch. Cleaning the surfaces down to a near mirror surface will almost certainly result in a HG with a short life.

 

Depends on the gasket type. Follow the gasket makers recomendations for surface finish.

 

GD

[nipper]

Machine smooth.... well, sort of..... smooth.... NOOO!!! If you've ever seen a freshly machined head/block you will notice that it is relatively rough to touch. Cleaning the surfaces down to a near mirror surface will almost certainly result in a HG with a short life.

 

http://www.aa1car.com/library/ic697.htm

 

 

do NOT tell somone he needs a rough surface if hes never done it before.

Thwey will usually make things worse. The surface must be smooth to a machined finish.

But hey waht do i know, pulling a wrench since i was 5 (45 now) and just an automotive engenieer.

 

 

nipper

[idosubaru]

Final tip (for now): My cam cases and heads were really difficult to break loose after removal of all bolts, despite whacking them with a rubber mallet and the like. Obviously, you don't want to pry between these things, so I finally braced a 2x2 about two feet long against the back of any protrusion I could find on the respective cases or heads and drove them loose by hammering on the end of the 2x2. .

this is the way to go. but first - leave two bolts still in place and only partially threaded in. you don't want the head/cam to come off and fall off the engine. leaving two bolts will allow you to break the head or cam free and they will catch it. otherwise they'll just fall off and onto the ground or bang around the engine bay. when removing the cams you want to attempt to keep the rocker arms in the same position, so it's best to knock the cam case loose and pull each rocker arm off by hand rather than knock it loose and have them all spill out all over the floor. on the cams i'll leave two bolts in and only leave them only 1/4" - 1/2" from all the way screwed in. this will give me 1/2" to break them free but doesn't allow the cam carrier to come out so far that the rocker arms fall off and all over the ground. with 1/2" clearance they'll stay in place but you can reach up there and pull them out individually and number or keep track of them however you like so they can be resinstalled on the same valve.

[idosubaru]

do NOT tell somone he needs a rough surface if hes never done it before.

Thwey will usually make things worse. The surface must be smooth to a machined finish.

i agree with nipper here. i'm not a machine shop expert but at the machine shop i deal with they always machine heads to a nearly perfectly smooth finish. well it looks and feels smooth to me anyway, i'm not sure what he means by "rough", i've never seen that done before. this machine shop i use is an aluminum head speciliast and i'm one of their very few customers, they mainly do reman'ed heads for NAPA. 'ive used a couple other machine shops in the past and they've all done the same. never heard of a "different" ways to do heads.

[Ross]

i agree with nipper here. i'm not a machine shop expert but at the machine shop i deal with they always machine heads to a nearly perfectly smooth finish. well it looks and feels smooth to me anyway, i'm not sure what he means by "rough", i've never seen that done before. this machine shop i use is an aluminum head speciliast and i'm one of their very few customers, they mainly do reman'ed heads for NAPA. 'ive used a couple other machine shops in the past and they've all done the same. never heard of a "different" ways to do heads.

 

Maybe why so many of you have HG probs with ea82t....... Unless you're using a metal HG, a smooth finish is not required - obviously it must be flat though, and when i say rough i dont mean pitted or corroded.

The head should be fine straight off a mill - no further machining required.

[GeneralDisorder]

The head should be fine straight off a mill - no further machining required.

 

Directly from Fel-Pro:

 

http://www.enjoythedrive.com/content/?id=25826

 

"The surface finish should be fairly uniform across the entire face of the head and block. In other words, the RA finish should not vary more than 20 percent from one area to another."

 

"Too rough a surface finish can also be hard on the gasket itself. A rough finish has more 'bite' and digs into the gasket more aggressively. This can increase the scuffing and shearing the gasket undergoes as the engine heats up and cools down."

 

"If the surface finish is too smooth [less than 54 RA], it may not provide enough bite to hold and seal a head gasket securely. There can also be movement between the gasket and metal, causing the gasket to abrade and leak."

 

"As a rule, the smoother the surface finish, the better. When the surface is rougher than about 113 RA (125 RMS), there are too many peaks and valleys on the metal's surface to seal properly. The gasket may not cold seal and could leak coolant and/or compression."

 

.....

 

Basically, you need a finish of about 60 to 80 RA for the conventional graphite gaskets. The MLS gaskets in the newer EJ's need a finish as smooth as 20 RA.

 

Herein lies the problem. A decent mill with a two blade cutter can produce RA as low as 10 or 12. Far TOO smooth in fact for a normal graphite gasket to "grip". Great if you are building up the new Ford engines that require RA of 15 or so, but bad for us older EA owners. A good shop needs to know that you need a ROUGHER surface than normal - belt sanding with an #80 grit silica carbide belt will land you in about the right RA range for an EA head.

 

You CANNOT see these differences. You need a meter for it - it's a tool that drags a diamond tipped stylus across the metal. Touch, feel, looking at it cross-eyed in the light of a full moon, etc are not viable options for testing this.

 

GD

[idosubaru]

something to ask the machine shop next time i have anything done. i've never had any problem blowing head gaskets but i've only done one turbo motor...haven't heard back from him yet?!

[flyjum]

Ok Thanks for all the info. The set I have i think has almost everygasket I need. Ill have more question when I start doing it. Do I have to unbolt the engine from the trans and rock it forward is that how you do it?

[idosubaru]

to remove the engine you have to unbolt it from the transmission. if it's an automatic you have to remove the flexplate bolts from the torque converter though the access hole in the bell housing (the little rubber plug under the intake/throttle body). if it's a manual, just separate them. gradually using a wedge, chisel, heavy duty screw driver, work your way around the bell housing and pry them apart. have the engine lift hooked up and take the pressure off the engine mounts as much as possible so the engine will come loose and float out ahead of the transmission.

 

and remember the head gaskets are easily done in the car. it'll take a good 2 hours at least to remove and reinstall the engine if everything goes smoothly (good luck). that's enough time to get the timing belts and cams off.

 

most gasket sets i don't think come with the cam carrier o-rings at the bottom corner. they are reinforced and have to be that way, a regular o-ring is not acceptable. the only place i know you can get them other than Subaru is http://www.thepartsbin.com. this is a must replace item when reassembling.

 

pretty sure you're a member there, but you know about xt6.net right?

[flyjum]

Yea I know xt6.net. I am a member. But do you have to unbolt the tranny to put the headgasket on with the engine in the car to like rock the engine forward? Also This set has alot of gaskets do you have a pic of this cam carrier o rings? Whats it called on the parts bin? Is it this? http://oem.thepartsbin.com/parts/thepartsbin/wizard.jsp?year=1986&make=SU&model=XT4-4WDT-001&category=A&part=Cam%20Support%20O-Ring&dp=false Mine kit came with those. My kit is the same as the Inshino kit has same parts but mine has a few more.

[GeneralDisorder]

You really should just get Fel-Pro HG's, and dealer for the other few you need - you are going to kick yourself later. Trust me.

 

GD

[flyjum]

The brand I got is eristic nobody has used them so I wanted to try them out and give a review.

[idosubaru]

you do not have to move the engine at all to do the headgaskets in the car. do not touch the transmission to engine bolts...no way. is there something that says to do that? we have the FSM Subaru Factory Service Manuals available at xt6.net that detail how to do this if you want some help.

 

those are NOT the cam orings i'm talking about. those are just the cam seals behind the timing belts, they don't require pulling the cam to replace. you need these...like i said, they don't come with gasket kits (or at least very rarely do), that's why you don' thave them:

http://oem.thepartsbin.com/parts/thepartsbin/wizard.jsp?year=1986&make=SU&model=XT4-4WDT-001&category=All&part=Cam%20Housing%20O-Ring&dp=false

 

here's the part number from thepartsbin.com if that links doesn't work:

#A4002-56062

 

more info on this o-ring at xt6.net including the subaru part. since it's common to all EA82 and EA82T and ER27 engines, i've found most dealers have these in stock. they're $2.15 at the dealers i use. they're located between the cam carrier and the heads.