Introducing Mike Corbin’s Blog!
July 21, 2009
Hello all and welcome to the Smart Service blog. I’m Mike Corbin, the owner of Smart Service. I’ll be writing this blog to provide you with friendly helpful information about your Subaru as well as other interesting things. Whether it’s the latest about Subaru head gasket solutions or local happenings in the Shoreline and Mukilteo community, check back, I’m sure you’ll find it interesting and enjoyable.
Keep up to date on Subaru related topics by checking back frequently.
Thank you,
Mike Corbin
Hi Mike,
We have for years seen subaru head gaskets fail not unlike you I’m sure. The last 19 that we’ve replaced, had one thing in common. A change was made in the design of the thermostat housing. The waterpumps were also changed. We found in all cases of gasket failure that when combusted gases make it into the coolant, the gases are trapped in the t-stat housing. The waterpump actually pulls coolant away from the thermostat and the temp sender is out of the coolant flow at that time. To remedy the cavitation of t-stat housing we replace the thermostat with one that has a bleeder. If aftermarket t-stats are used, for the most part they have no bleeder. This accounts for the lack of customer complaint of overheating since the sender is telling the gauge that the engine temperature is fine.
IAM AN OLD MECHANIC, OR JUST OLD ALL OF HEAD GSKT HOW TO`S DONT SAY HOW OR IF YOU OIL THE NEW HEAD BOLTS DURING HEAD REINSTALL` WHATS YOUR TAKE ON THIS` I HAVE FEAR OF OIL SQUEEZING OUT NEW HEAD GSKTS BUT DONT WANT TO STRIP THREADS THANKS FOR INPUT
Subaru recommends oiling the threads on the bolts prior to torquing. We agree with this recommendation. We also encourage you run a tap down in the holes to insure they threads are in as good of shape as possible. Based on our experience at Smart Service, we’ve never had a problem with oil squeezing out onto the head gaskets.
Goos luck,
Mike Corbin
Smart Service
Independent Subaru Expert
Mike,
I’ve enjoyed much of your advice on head gasket replacement. Been doing my own work for 35 years on different cars over the years. Not new to subaru engines, for my son had a 1990 1.8 that we did head gaskets on. Now I’m working on a 2001 Outback 2.5L, car has 116K miles on it, no blown head gasket, but with my daughter going off to grad school in Cheney I feel that for preventative maintenance I do the head gaskets. Ya know it’s all about me! If anything were fail on the car, I’ll get the call. I did purchase the new Phase II Six Star gasket for this job a couple weeks ago.
I’ve got the heads off now. But as I was taking the driver side cams off the sprocket spun forward a bit more than 180 degrees. I was following the Haynes procedure which mentioned that was the next step. I should’ve paid attention to some of the practical experiences others have recommended not taking the sprocket and cam rocker arms off.
What do I need to to in this case? Please advise
Jim
Hi Jim,
It seems now all you need to do is remove the heads and inspect that particular head for any bent valves or valve leakage. It’s probably OK but you’d rather find out about it now than when the heads are off than later when you can’t figure out why it’s running bad.
On a side note, I’ m not sure I’d put my faith in a Haynes book for that extensive a repair on a Subaru. I would recommend obtaining a genuine Subaru manual or purchasing an online Alldata subscription for that vehicle. (they use Subaru manuals for their info). I’ve just seen too many mistakes made from a DIY using Haynes or Chiltons.
Good luck,
Mike Corbin
Independent Subaru Expert
Hi Mike,
Just replaced the right side head gasket in my 2001 Legacy with a Six-Star which I ordered from your shop. This was after my shop here on the west coast said the problem I had with coolant loss and fluctuating temperature gauge was due to bad gasket. My car had 155,500 miles at the time and that head gasket was original. The left side gasket they replaced at 74,500 miles and they say it’s fine. Problem is, if I drive a number of highway miles at higher speeds, I end up with a reservoir full of coolant, not as much in the radiator, and a temperature gauge which is once again going into the red. If I drive locally (slower speeds), the coolant level remains normal in the radiator. I had my local Subaru dealer remove any air from the cooling system, but that hasn’t helped. Have you ever seen this problem with any cars in your shop?
Hi Chuck,
I have seen this problem and unfortunately it appears the Subaru wasn’t properly repaired or something was overlooked somewhere along the way. I bet you will find hydrocarbons in the radiator if you were to have it tested.
My theory is that you have exhaust pushing into the cooling system from the combustion chambers. A helpful test may be to remove all the spark plugs, apply a pressure testor to the radiator then after a few minutes of having the (topped off) cooling system under pressure, crank over the engine. If it’s a big leak you’ll have coolant shoot out of one of the plug holes. The reverse method of this is to pull the plugs, bring each cylinder up to TDC and apply air pressure with a leakdown tester to that particular cylinder. If you see bubbles coming out of the radiator then you’ve narrowed it down to that cylinder.
Now, the question is why did this happen. Was the head gasket that was replaced at 74k bad also? Was there a crack in the head or block that went un-noticed? Was there imperfections in the head or block that prevented proper sealing?
There’s a myriad of reasons it may have happened but without seeing the car it’s difficult to tell.
Good luck,
Mike Corbin
Seattle Subaru Expert
Thanks Mike. Looks like a tough thing to diagnose. Also, meant to say I am on the east coast, not west, or else I would bring my car to you. Do you know of any good Subaru mechanics near Philly?
Chuck
Sorry Chuck,
I don’t have any referrals for Philly. Just do your research on the different review sites.
Take care,
Mike