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Doing '01 H6 head gaskets, parts advice appreciated

Featured Replies

 

On 8/6/2022 at 11:39 PM, jonathan909 said:

As they say out east, Lord Tunderin' Christ.  I get now why GD says "replace it". ...

Holy smokes - 150 (sounds like some specific) screws.  A respectable job so far. Everything is now disassembled? 

I guess the 'H6 head gaskets never go bad' thought isn't true. Still, the fact it's not as often and the engine has a timing chain is appealing. 

Edited by Stelcom66

  • 2 weeks later...
  • Author

Well, here's the coda:  I was deeply apprehensive about this assembly because I was suffering severe creak on most of the head bolts during the torquing.  Some of them had spots of pitting on the threads and I should have replaced them, but simply didn't have the time, given this summer's circumstances.  So I cleaned them up as best I could, degreased and blew out the block holes, lubed 'em up and forged ahead.  Probably should have chased the block threads as well.  Anyway, the torquing was all my best SWAG, as I figured that if I could get anywhere close to the final ft-lb spec, the creaking probably wouldn't matter as I did the final angles.  We finished slapping it together last Monday and ran it around town, putting on 200km in 30C weather with the AC blasting.  When it held, I figured it was worth trying on a more serious trip.

So last night we got back from MT - 1800km since the rebuild, and most of the trip in 30-35C ambient.  Unfortunately, the AC stopped blowing cold when we got down there, but the clutch is still engaging, so I figure it's a hard O-ring and some lost refrigerant.  And an O2 sensor decided to pack it up an hour or so from home, but that didn't cause any problems.  And with the four of us, all our kit, and towing a trailer carrying both a Sea-Doo and a sailboat, the a$$ was nearly on the ground (I'd bought new shocks for it last summer, just hadn't gotten to them in yet, and am doing them now).  But the engine temp was rock-steady-eddy throughout the trip, so it looks like I dodged a bullet.

And now I'm going to dive into our other '01 H6 - the one I bought about a month before the initial COVID lockdown, $500 because it too needs HGs and the PO was clearly in way over his head when he thought he could change them in his back yard (not only no garage, but on his lawn).  Sadly not the all mod cons of this one (i.e no VDC or McIntosh - sniff), but body in better overall shape.  It'll be a first if we can actually go into this winter with every car running...

Edited by jonathan909

8 hours ago, jonathan909 said:

Well, here's the coda:  I was deeply apprehensive about this assembly because I was suffering severe creak on most of the head bolts during the torquing.  Some of them had spots of pitting on the threads and I should have replaced them, but simply didn't have the time, given this summer's circumstances.  So I cleaned them up as best I could, degreased and blew out the block holes, lubed 'em up and forged ahead.  Probably should have chased the block threads as well.  Anyway, the torquing was all my best SWAG, as I figured that if I could get anywhere close to the final ft-lb spec, the creaking probably wouldn't matter as I did the final angles.  We finished slapping it together last Monday and ran it around town, putting on 200km in 30C weather with the AC blasting.  When it held, I figured it was worth trying on a more serious trip.

So last night we got back from MT - 1800km since the rebuild, and most of the trip in 30-35C ambient.  Unfortunately, the AC stopped blowing cold when we got down there, but the clutch is still engaging, so I figure it's a hard O-ring and some lost refrigerant.  And an O2 sensor decided to pack it up an hour or so from home, but that didn't cause any problems.  And with the four of us, all our kit, and towing a trailer carrying both a Sea-Doo and a sailboat, the a$$ was nearly on the ground (I'd bought new shocks for it last summer, just hadn't gotten to them in yet, and am doing them now).  But the engine temp was rock-steady-eddy throughout the trip, so it looks like I dodged a bullet.

And now I'm going to dive into our other '01 H6 - the one I bought about a month before the initial COVID lockdown, $500 because it too needs HGs and the PO was clearly in way over his head when he thought he could change them in his back yard (not only no garage, but on his lawn).  Sadly not the all mod cons of this one (i.e no VDC or McIntosh - sniff), but body in better overall shape.  It'll be a first if we can actually go into this winter with every car running...

Lubing the threads should avoid creaking. Maybe higher quality or ensuring it’s getting all the way down the thread bores.

I too have towed huge boats and other things over the weight limit and had them sagging.  Replace the rear springs while you’re doing struts. I’ve done H6 struts only to have to do the springs shortly afterwards due to horrid ghost jumping from warm springs. Car rear “jumps” randomly sideways a little while driving over bridge joints. Not a very good feeling at highway speeds. Feels like driving in winter..in the summer 

  • Author
1 hour ago, idosubaru said:

Lubing the threads should avoid creaking. Maybe higher quality or ensuring it’s getting all the way down the thread bores.

"Should" is the keyword there.  I always lube anything that needs to be torqued - in this case I used the Amsoil assembly lube since I used it (at GD's suggestion) on the '06 H4 I did in the spring (it worked great on that one).  On this one, even with it they creaked like crazy, so I cleaned and re-lubed with regular oil - no change.

1 hour ago, idosubaru said:

I too have towed huge boats and other things over the weight limit and had them sagging.  Replace the rear springs while you’re doing struts. I’ve done H6 struts only to have to do the springs shortly afterwards due to horrid ghost jumping from warm springs. Car rear “jumps” randomly sideways a little while driving over bridge joints. Not a very good feeling at highway speeds. Feels like driving in winter..in the summer 

This was a greater-than-usual load, but by no means "huge".  I could check, but I think the TriFoiler, Sea-Doo, and trailer itself are around 500lb. each, and those are highball guesses.  This just had to do with the old shocks being flat.  Since I first noticed they were low last summer when I started driving the car and I was getting weird VDC errors through relatively gentle corners, I made a point of getting the recommended KYBs.  We'll see how it does.

Interesting on the creaking. Subaru springs generally last the life of the vehicle fairly well so reuse is the norm. Just my preference to replace on anything that's pulling weight and headed for 200K+ miles. Probably more because I hate compressing struts any more than I have to.....none of the compressors work well for Subaru struts. lol

  • Author

Fortunately, not struts on the rear of this car, just shocks within springs.  So no compression/assembly required, just "put the floor jack under the shock to compress the spring enough to get the knuckle bolt to line up".

2 hours ago, jonathan909 said:

Fortunately, not struts on the rear of this car, just shocks within springs.  So no compression/assembly required, just "put the floor jack under the shock to compress the spring enough to get the knuckle bolt to line up".

All Subarus front and rear since the 80s are the same (except early 90s leg and late 80s XT/EA air suspension) configuration and require compressing springs to swap the strut only. Subaru calls them struts:

https://www.subaruparts.com/oem-parts/subaru-strut-20365ae15a?c=Zz1yZWFyLXN1c3BlbnNpb24mcz1zdHJ1dHMtYW5kLWNvbXBvbmVudHMmbD0xJm49QXNzZW1ibGllcyBQYWdlJmE9c3ViYXJ1Jm89b3V0YmFjayZ5PTIwMDMmdD12ZGMmZT0zLTBsLWg2LWdhcw%3D%3D

 

  • Author

Sure, but this is nitpicking.  It's not a "strut" in the sense that the fronts are, with the tophat and taking the form of a single assembly in which a compressor is needed to swap an old spring onto a new shock.  It's just a shock with a support for the bottom of the spring, as the top of the spring presses up against the body, not a tophat.

36 minutes ago, idosubaru said:

All Subarus front and rear since the 80s are the same (except early 90s leg and late 80s XT/EA air suspension) configuration and require compressing springs to swap the strut only.

sorry, but they are NOT the same

I can not put rear shock/strut from the other half's outback on my forester, and vice versa.. they are completely different beasts

his are small and look like an old school shock absorber with only one bolt at the bottom... mine are the larger struts that bolt to the hub with 2 bolts

Call them whatever you like, they are not the same for "all" Subaru's since the 80s

  • Author

Well, since I've never formally studied the matter... https://en.wikipedia.org/wiki/MacPherson_strut

According to this, a MacPherson strut is a steering component, so it applies only to the front end.

What Subaru's doing in the rear is another question.  Does it qualify as a Chapman strut or similar?  Not sure. https://en.wikipedia.org/wiki/Chapman_strut 

Are there others?  Dunno.  I'd just call it a coilover shock unless someone can point to something more definitive.

16 hours ago, heartless said:

sorry, but they are NOT the same

I can not put

That’s not what I said. I said same ***configuration** meaning requires compressing a spring to replace. I didn’t say they’re interchangeable and no one would assume that since that’s not the context of this discussion.

whatever it’s called - the spring needs compressed to replace it.  He said there’s no spring to compress, that’s not the case  


 

 

17 hours ago, jonathan909 said:

  It's just a shock with a support for the bottom of the spring, as the top of the spring presses up against the body, not a tophat.

It does have a top strut mount. The spring does not press up against the top of the body. Maybe you leave the mount in and press the spring in place via the jack but you have to compress a spring to replace.

You originally said - no compression needed.  That’s what I was trying to make sense of, not word choices.  because a spring does need compressed.  I’ll blame this on semantics or limitations of a keyboard, I was thinking at first maybe you had never done rears before.

Edited by idosubaru

  • Author
1 hour ago, idosubaru said:

whatever it’s called - the spring needs compressed to replace it.  He said there’s no spring to compress, that’s not the case 

Please.  We're going in circles - and you're misquoting me.  What I actually said was "just 'put the floor jack under the shock to compress the spring enough to get the knuckle bolt to line up'. "  Yes, there actually is a top hat there (I mispoke when I said that the top of the spring is in contact with the body), but it's a "passive" part (i.e. no bearings) and its replacement is optional.

A MacPherson strut is a self-contained assembly in which the spring is captive to the shock portion, and special tooling (a spring compressor) and a separate operation are needed to assemble the two parts into a single component prior to installation in the car.

This is completely different from replacing the rear shock (as I just did with this pair of KYBs, which did not come with new tophats), in which the new shock is poked up into the spring from beneath, and a floor jack is used to slightly compress the spring (i.e. a inch or two) in order to align the shock's bottom mount with the knuckle, not to significantly compress the spring.  Yes, some come with new tophats and are replaced as a (slightly) precompressed unit, but again, that does not significantly alter the fundamental difference, which is that in the case of the MacPherson strut the spring is seriously compressed and the tophat bearings form part of the steering gear.

So we should now be clear that the rears are not MacPherson struts.  If you still want to claim that they are a different type of strut (e.g. Chapman), perhaps you can offer a citation or reference clearly indicating what type it is.

Otherwise, can we please kill this thread?

  • Author

Though there is one other thing I wanted to mention - on the subject line's advertised topic.

As I said, I ordered the Mahle head gaskets (which turned out to be Subaru OEM) and the Fel-Pro kit for the other bits.  The other choice for a kit was the Ultra-Power - $15 more than the Fel-Pro, and a lot more parts (except, strangely, the spark plug cover seals).  I went for the Fel-Pro.  But what I received was the Ultra-Power (though they charged me for the cheaper Fel-Pro), and when I looked back at Rock, I discovered that the two different kits have the same part number.  No point in asking Rock about it; their "customer service" is "what you see on the site is what we have, if you don't like what you got send it back".  In balance, it was probably better that I received the Ultra-Power kit because that gave me the water pump, oil pump, and crankshaft seals that aren't in the Fel-Pro.  But it had me scrambling around to find some good used EJ25D spark plug seals around my garage, as I wasn't about to pay the dealer $13 each for them.  Still, though, kinda weird.

Edited by jonathan909

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