2006 Tribeca HEAD GASKET JOB

[subarusaver]

HERE WE GO AGAIN...UGHHH

2006 Tribeca 3.0 H6

Just bought a 2006 Tribeca one owner with 149000 miles...seemed fine the day I got it....One week later ,top radiator hose on passenger side developed a small hole and made the engine overheat a little.All this time,I noticed the defroster only put out hot/warm air on the driver side and all the forums say that's a stopped up heater core...Every time I turned the defroster on , the engine temperature would immediately start to rise, then I could bleed the air out and/ or turn the defroster off and the engine temperature  would drop immediately .WELL ....maybe its the heater core for some people,  not me...So I made a loop and hooked the heater core supply lines together so coolant stays in the engine only..I placed a funnel in the radiator and filled it half way and after about fifteen minutes of idling I still get bubbles and when the engine revs they are even more pronounced...

1) Since I am doing the Head gasket job, are there any special odd things to consider for this engine?(Ive been through this process with my ea82, and with my ej22, and my 1.8 Nissan Sentra).

I just want to be prepared

2)Is there a best way to check the heater core while I have the engine out?

3)Since this one has a timing chain(and its really quiet btw) anything special things there to consider?

 

Thanks all for any insights!

 

[1 Lucky Texan]

If no, or limited info here, check over at subaruoutback.org

several posts about H6 work there.

[idosubaru]

For your message.  Thanks for posting then asking.

It’s a beast of a job. A JDM engine makes a lot of sense on these. 

It was sold because of bad headgaskets,  happens all the time, due to the intermittent way that engine fails they’re prone to get sold to an unsuspecting buyer.

Those heater cores do clog but they don’t cause overheating, they just cause cold heat. So yeah just clean them out to get your heat back. So you had two issues - headgaskets and clogged heater core.  They’re unrelated in this case  

The timing chains last the life of the vehicle, if there’s no noise and you plan on reasonable oil quality and changes there’s nothing to replace.  I’d replace the water pump because they’re only $100 but they really never fail either so take your pick. Use OEM.

theres a tub of orings you’ll need for the timing covers.

resurface the heads and use Subaru OEM gaskets. I don’t even think about checking for flatness any more, maybe I should but every Subaru head I’ve ever done has high and low spots but the H6s I’ve done are worse on average than the H4s.

other than Tribeca engine removal being a little harder and the dual H6 timing covers 100 annoying hex bolts and 3 miles of sealant it’s a standard Subaru headgaskets job.

on tribecas I’ve had to remove part of the upper radiator support (it’s bolted unlike every other Subaru that was welded), no big deal just a Tribeca thing to be mindful of. 

Edited October 21, 2018 by idosubaru

[subarusaver]

Thank you for the reply! I plan on Mobil1 Full Synthetic 5w30 and very regular oil changes, I like 3-4000 miles.Is there any special:

1) coolant brand/ type

2) rtv  brand/type( I really like the pressurized cans)

3) and where to download a good Field Service Manual

Thanks again for any help!

[Mike104]

Go here for manuals

https://sl-i.net/FORUM/showthread.php?18087-Subaru-Factory-Service-Manuals-

[idosubaru]

1. Get an owners manual for fluid specs and more, but that should be generic coolant like all older Subarus. 

2.  The Right Stuff is awesome if you mean timing covers. Permatex anaerobic is the perfect fit but pricey and two part. 

3.  He just answered that, google and you’ll find them too

 

[GeneralDisorder]

Throwing away full synthetic after only 3-4k is a waste of money. Go with longer intervals and spend the savings on proper synthetic like Amsoil. Mobile is consumer grade and OEM specified - not the best you can get.  

Don't even bother doing the HG's. Just get a JDM engine. Not worth the labor to do it. 

And I would highly recommend dumping the Tribeca and getting an Outback or similar after you "fix" it. Those were limited production and were not an economic success. They never worked out all the bugs and they discontinued the platform. It will not be a viable platform long term. 

GD