The AUSubaru.com.au Forums

Hi, new to this and hoping to get some advice on a problem. My Forester X (MY06, bought new end of '05) has 155,000 on it and has been faultless (I look after it very well). However, last weekend it started misfiring and I took it to the mechanic the next day (sube specialists). They identified a misfire in cylinder 4 and took the head off to find a bent exhaust valve and small dent on piston. They thought I must have been flogging it and that caused the damage but when investigated further it was found the valve guide had dropped. It was the right size, but they said the hole for it was too big. 3 of the 4 valves, on that side of the motor, had a similar problem. They said the fault probably occurred during the production of the motor (ie, the machine that bored the holes for the valve guides made them slightly too big). They are going to fit bigger valve guides but asked me if I wanted the other side checked too. I said yes because I still plan to keep the car. I could not find any other instance of this occuring on this forum (but did find one on a Nth American forum) and the mechanic said he'd never seen it in 28 years working on Subarus. I'm hoping it's a one off bit of bad luck but wanted to get some other opinions on this,

John

That shouldnt have happened, but if you're planning on keeping it for a while then its worth getting whole heads checked (left and right sides)...
Keep records of the job that has been done..
Is it under warranty?
Cheers
AP

Thanks AP, no it's not under warranty...so it's going to cost me a bit (they were getting prices on parts yesterday). They said they'd give me 6 months/ 10,000 km warranty on the work. The mechanic is worried because his daughter has the same model, but less km's on it. I think it's just a rare quality control issue at the factory. The only symptoms I noticed prior was a couple of splutters going up hill, this was over the last couple of months, but apart from that, the car seemed bullet proof.

I'll write a letter to Subaru and see if they'll cover part of the cost, but I don't see why they would. Nothing to lose though..maybe ask for a rebate on the next Subaru I buy off them,

John

Evergreen wrote:Thanks AP, no it's not under warranty...so it's going to cost me a bit (they were getting prices on parts yesterday). They said they'd give me 6 months/ 10,000 km warranty on the work. The mechanic is worried because his daughter has the same model, but less km's on it. I think it's just a rare quality control issue at the factory. The only symptoms I noticed prior was a couple of splutters going up hill, this was over the last couple of months, but apart from that, the car seemed bullet proof.

I'll write a letter to Subaru and see if they'll cover part of the cost, but I don't see why they would. Nothing to lose though..maybe ask for a rebate on the next Subaru I buy off them,

John

Fair enough
Cant hurt to try with Subaru - Good Luck!
Cheers
AP

Evergreen wrote: I'll write a letter to Subaru and see if they'll cover part of the cost, but I don't see why they would. Nothing to lose though..maybe ask for a rebate on the next Subaru I buy off them,

John

A bloke that I used to work with had head issues with his 4 runner which was about 5 years out of warranty and second hand, But had toyota approved servicing from day one and took it in to toyota where they discovered it had lead to minor damage to the block and pistons, So all was replaced as it was proven to be a toyota defect. In the end all he had to pay for in a brand new engine was the con rods and the bearings!

Must have had it sideways something serious for a valve guide to 'drop' on a boxer

It would be interesting to know the service history of the car. Oil changes intervals and oil grade and quality are becoming issues.Spoke to a meckanic who was doing a Jag that was only 6 years old went a bit too long between oil changes on mineral rather than synthetic and spun a bearing. No undersize bearings available so new $4k crank had to be included in the $15k bill for the AWD monster

Thanks for comments guys. I only just picked the car up a couple of hours ago. $2622 in total (plus I had to rent a car whilst it was in the shop). The car has a perfect service history but I can only trust the mechanics on the quality of the oil (all reputable, subaru specialists). The motor's had an easy life too, very little stop/start for the km's and I am the only driver. I drive like an old woman (haven't had a ticket in 20 years).

The valve guides on the other side of the motor (cylinders 1 & 2) hadn't dropped...but the guys who pressed them said they came out easier than they should have. Interesting story about Toyota, I'll see if I get any acknowledgement from Subaru....

John

Evergreen, I would have tried to do without your subi (hard I know) and discussed it with subaru before any work was done, I doubt they'll come to the table on this one - you may be lucky if the work was done at a subaru dealership...

steptoe wrote:It would be interesting to know the service history of the car. Oil changes intervals and oil grade and quality are becoming issues.Spoke to a meckanic who was doing a Jag that was only 6 years old went a bit too long between oil changes on mineral rather than synthetic and spun a bearing. No undersize bearings available so new $4k crank had to be included in the $15k bill for the AWD monster

I highly doubt oil changes or quality would be the culprit here - valve guides are pressed into the head and the oil only lubricates the stem of the valve against the valve guide, basically the valve guide should remain static its whole life - they should defenetly not be touring around!

Tough luck on picking that up with a pre purchase check of the vehicle! At least now you'll know its all back in good order. Did they do anything about the "dent" in the piston? Hopefully not, but that could possibly lead to other issues down the track if the face of the piston has been weakened.

All the best with it!

Cheers

Bennie

Thanks for the reply Bennie. They didn't do anything about the piston, the mechanic said the valve just "kissed" the piston. I saw it and it looked horrible to me, I wouldn't put up with a dent like that it if it was the outside of the car, but I trust the mechanics advice.

I've got a letter in with Subaru, but am not hopeful. When something like this happens you begin to find a lot of people with unsuccessful complaints, so I think Subaru will just throw my one on the pile. I agree with you, I might have had a shot if I'd stuck with dealer servicing.

The car's going great now...I rented a Suzuki Swift for a couple of weeks and am very happy to have the Forester back..more power, more comfort.

John

Just wanted to update the valve guide situation in case it of use to anyone. My car now has 210,000km on it and hasn't had any other problems since the valve guides were replaced. I still get around 8ltr/100km (premium) and the engine feels as strong as ever.
Subaru replied to my letter back in Jan 2010 and said there were no other reports of this problem so they didn't feel it was their fault. Fair enough I thought, plus the car was out of warranty anyway. Just had a check and doesn't look like anyone else has had this problem since, so it must have been a one-off.

John

I wonder if mineral oil had been used the residue would have filled any gap or clearance created/manufactured buy say valve guide being in min OD and valve guide bore on max OD.