Hello! I have a 2.5 2007 WRX (hawkeye) and the headgasket has just gone. I'm going to get it fixed however I'd like some advice on which route to go down as I'm not overly clued up on certain things! I understand the heads may need to be skimmed which may produce problems further down the line, so my question is, would it be worth going forged and if so how much roughly does something like that cost? Bear in mind this is only a WRX so would it even be worth it . Or would it be better to just get the engine repaired and hope it doesn't start throwing problems at me again in a few months. I have a guy who is going to do it for me (I'd love do to it myself but sadly don't have the space or the tools), and he is pricing me up a worst case quote for me. When the HG goes what typically are the other things that would need to be replaced? A few people have said to me pistons and bearings as if the head needs to be shaved it will ever so slightly alter compression. If it doesn't need to be shaved would a HG replacement suffice?

Sorry for the long post!! I'm just after any and all information people have on this really

 

Skimming the head is good practise if you’ve suffered a head gasket failure as overheating can warp the heads, but skimming doesn’t cause any issues as thicker head gaskets are used to make the difference back up, thus not altering compression.

Many people go down the forged route when head gaskets fail as it’s often half the cost of a rebuild just to get the head gaskets replaced. With it being a WRX it can still be built to a good spec that will handle lots more power and increase reliability. A lot will come down to the budget you have to work with. Who is doing the head gaskets for you? A known specialist?

 

Ahhhh okay that makes sense, I wasn't aware thicker gaskets were a thing lol! A guy near Colchester Essex is doing it for me - Yanman Racing(Watkin's & Sons) I don't think he is very well known but he deals with a lot of Subarus and has done work on my car before so I trust him with it! Ideally 3-4k would be how much I'd like to spend (again no idea if this is reasonable), however if when he takes the engine out there is worse damage than we thought I could spend up to 7k if I really needed to. My car only overheated the once that I saw, there wasn't any nasty knocking's, just the muddy radiator and my hot air blowing cold every so often. It only happened twice before I went to get it tested so I'm hoping it's not too bad

 

7k on an engine with 5 speed oem turbo ecu etc ,think i will not spend that on wrx.
on the other hand i spent 5k for coilovers, clutch and some paint on my sti ,more paint plus engine,turbo followed by underside job. its never ending story

 

If it was me I'd buy this, skim the heads and job done, these are supposed to be able to handle 400bhp. You won't have to mess with engine builders.
https://www.importcarparts.co.uk/par...ck&searchPart=

 

Is this just a daily driver or a high performance track car? If it's the former, then be mindful of Subaru's own advisory and put some of their additive in the coolant system (turns out it's Holts Radweld) and before you scoff, consider this:the reason the hg fails is 'cos its the errosion of the graphite that's sandwiched between the laminations of the gasket. Seen the youtube vids?

Remember, this is a Subaru advisory!
On a personal note. It worked for me on a 20+ year old Impreza, 7k miles and 3 years later, its still working and it regularly enjoys high-speed runs., with the temp gauge needle staying rock solid at half way. So, don't be be like Pavlovs dogs; hg gone therefore must spend £7k on engine reubuild...... look at those youtube vids and read the comments. It really does work and will save your Subaru.

 

this is very interesting and the first time I’ve heard about it. Makes sense if you think about it. Interested to know if anyone else is doing / using it ?

 

Worth a go i'd say, will keep this thread in kind if ever happens to me.

 

LOL I've only just heard about this!

Well no I haven't. This is EXACTLY what Jaguar did in the 70's and 80's during the British Leyland era; Adding one or two sachets of "Bars Leak" (same as Radweld), after every coolant change.

See attached pic of XJ workshop manual

Problem is what happens after doing this for 20+ years? Well, everything plugs up, especially if the cooling system gets a bit of air in there. And partly why Jag V12's got a bad rep for cooling system problems...what would happen is one half of the radiator would plug up, problem is one half of the radiator does one cylinder bank, so the cylinder head that gets flow from that part of the radiator overheated. Made worse if was the cylinder head on the opposite side to the temperature gauge sender, which would read normal. Overheated cylinder heads had a nasty habit of dropping valve seats causing piston/valve contact.

So in mind of that, I'd avoid letting that stuff touch any of my engines; I still get the odd "clump" of gunk out tge Jag when I flush it...a relic of its main dealer servicing during its first 15years, so potentially had ten sachets of the stuff put in there.

Usually gasket erosion is simply due to lack of regular coolant changes (5yrs max) and/or wrong antifreeze. If it turns acidic it'll actually cause more corrosion rather than prevent it.

 

Also interesting , but providing you had no leaks in system then does it work by plugging small cracks / channels starting to form on heads and thus preventing big failure or just delaying the inevitable and maybe adding to it ?

 

Subaru head gaskets of the laminated variety (with the graphite sandwich) start to erode nearing 90k miles, (or so) so it's a preventative measure..... Thats my understanding anyway..... but it fixed mine after it failed, so that's good. AND it means you can keep an old model going, after all, who's going to shell out £7k* to rebuild an engine on a car worth, what, £2k...?
*is that how much it costs? *

 

To answer the OP's question: 1stly I'd use the Radweld/coolant conditioner to get me back on the road, then plan on changing the head gaskets at some future date, but NOT faff with engine rebuild stuff, just replace the faulty hgs. Plenty of guides on youtube.... all US ones, get it done in a day! Get the oil seals in the sparkplug tubes replaced while you're at it.

 

So my engine has been taken to bits and the heads sent off to be tested…
my mechanic has informed me that my engine has definitely been in bits before as there are some bolts missing, and that it might even have a forester bottom end on it!! Wtf!!!! This would explain why the Hawkeye CV joint he tried to fit a couple years ago couldn’t fit, but he had to order a forester one instead. Quite odd. I bought the car in 2020 and there is no paper work to suggest it’s had an engine swap / rebuild in the past.

maybe anyone here knows who owned it before?, original reg is YX07 JZO.

 

Interesting fact the CV joint is on the driveshaft which connects to the gearbox not the engine.
We are talking about a Hawkeye WRX ? and if you are talking about a rear CV joint they are common with the MY03-08 X & XT Forester; MY08> R & WRX models and various B13 Legacy models.
He was probably trying to fit an STI version which is different.

http://opposedforces.com/parts/info/28492AG010/

Similarly the EJ255 short block is common between many models

http://opposedforces.com/parts/info/10103AB630/

 

Oh yeah duh.. brain fart moment! My car is an 07 Hawk WRX yes, it was a front CV joint.

That is interesting, I'll find out more info when I go to see it soon, just trying to get my head around it at the moment, still learning how it all works anyways, so this is just a mind boggle 😂 I'm trying to find the prev owner to see if I can get some light shed on what it's actually had done to it.

 

Front CV joint common with some legacy's.

http://opposedforces.com/parts/info/28392AG000/

 

CV joint isn't an issue now, more confused with actually what's been done to my engine hahah!