Gasket Replacement to fix Oil Leak

So I have had a small, but constant oil leak on my 06 2.5i non turbo (129K mileage) for awhile now, but recently it has seemingly gotten worse. I have replaced the the passenger side valve cover gasket (cause that is what I originally thought was the origin), but have continued to see some leaking oil. Never had a puddle under the car, but the oil does tend to hit the exhaust and burn off.

 

Now I took the car to a mechanic to track the leak origin. They told me it was the rear lower corner of the driver side head gasket (they used oil dye and a UV light to check, I will be double checking at a friends garage) and wanted to charge me $1500 bucks for the job and included a timing belt. I understand this is a normal price in my area, but is still high for me and I am looking to do the work myself.

 

Now to the actual questions....

1) How huge is the difference (performance, durability) between a Felpro complete gasket swap and an OEM gasket replacement set? I have found a slight price difference favoring the Felpro ($50 cheaper)

 

2) While in there should I change the water pump?

 

3) People have told me to also change over the timing belt and pulleys while in there as well. but I had to change out a cracked timing belt cover a little while ago and checked the belt, it seemed fine (had been replaced by previous owner) but I am unsure as too when it was done. Is this a recommendation to change (pulleys and belt?)

 

Thanks for the help guys.

You may want to PM Nrw, ask him if he can help you out.

 

I'm not up on 2.5i's.

 

 

If the belt was replaced at 105K like GT's are all those pieces should be fine.

 

GTTuner, may be someone else to PM.

I've always heard/read/been told to use OEM gaskets (For head and VCG)

That's all I've got to contribute.

Given a broken timing belt = bent valves 95% of the time, it's worth throwing a new one on there while you're in there.

 

If I'm going into a 100k mile Subie engine I plan on keeping on the road for another 100k, it gets the following:

 

Headgaskets (OEM or Six star, although Felpro has supposedly figured out how to build them for the 2.5's now)

Cam & crank seals

Oil pump o-ring

Oil cooler gasket (if applicable. . . it's a turbo/H6 thing mostly)

Timing belt (OEM)

Timing component set (everything the timing belt touches that isn't a cam or crank pulley--I'm ok with aftermarket stuff here)

Water pump (OEM)

Tstat (OEM)

Valve cover gaskets (OEM)

 

You can do HG's in the car but it's not any faster or really less effort IMO. Engine out.

Just double-verify that it actually is the head gasket and not something else. The valve cover gaskets and the spark plug seals are two rather common items for oil leaks on an older engine, as are the cam seals.

 

Easiest way to find the leak is to clean the area completely, then jack up the front end of the car, start the engine and let it run for a minute or two, then stop, get under and look. Use a paper towel to close in on the problem.

 

Looking at the picture below - the item circled in red is the oil feed to the cylinder head, which is under pressure, and therefore more likely to leak. The items circled in green are the returns from the head to the block and sump. If the leak is where they claim it's at the rear end at the green part under the oil feed. However that means that you should have experienced other problems with the engine than just an oil leak. The most likely place for a cylinder head oil leak is at the oil feed.

 

From my understanding you have a SOHC 2.5i engine (I maybe wrong), and that has what's called a camshaft cap which is holding the camshaft on to the head. This also has a seal which is using liquid gasket to seal against the cylinder head. It's possible that the mechanics has mistaken this seal for the cylinder head seal (for some obscure reason). In any case - if that seal leaks it may have been caused by a clogged PCV or other crankcase ventilation problem so you may want to check that too.

 

Other items that may leak are the camshaft seals.

 

Personally I think that the workshop was trying to rip you a new one, so you should look out for someone that's trustworthy and knows what's up with Subies.

 

http://www.bedug.com/pics/Subaru/headoil.jpg

Actually the older 2.5's (pre 2004) are notorious for leaking right where the green circles are. Headgaskets are comically thin and the graphite coating erodes away, then you get oil leaking externally.

Thanks for the information guys, it has been very helpful thus far. I am going to be double checking the leak myself. I have a friend who has the UV light to check the dye that the mechanic put in (even it is spread everywhere now, should still have a concentration point at the leak). I have heard that the valve cover gaskets and spark seals are notorious for leaking on my car and I have started the process of replacing those (did the passenger side, have the driver side parts haven't had time). I am pretty certain the leak is not from the oil feed though, there is barely any (if any) oil on the top side of the valve cover/head area. any oil that I am seeing is on the underside of everything.

 

I have priced out the parts for a full engine gasket set for the motor along with the timing belt and water pump and it comes to around $600, which is nothing compared to $1500. I am thinking it might just be worth going through everything with a fine tooth comb, especially since the motor is approaching 130K and I do not know what the previous owners did to it. Would probably wise to go ahead an replace everything while in there? (once I confirm that it is indeed the head gasket)

You can do HG's in the car but it's not any faster or really less effort IMO. Engine out.

 

I am planning on just pulling the motor to do the work. I replaced the valve cover with everything still tight down and it was a pain. So with that type of engine work I want to at least be comfortable doing the work haha

Sounds about right for parts prices, and yes, it's worth doing everything if you're not sure it's ever had the timing belt or tensioner/idlers replaced. I don't buy gasket sets for these as they usually come with a bunch of junk you either don't need, don't have, or won't be removing. I just piecemeal everything, usually from OEM sources. Headgaskets, intake gaskets, cam & crank seals (don't bother with the rear main, they rarely leak), oil pump o-rings, valve cover gaskets with spark plug grommets, maybe a donut gasket for the y-pipe if I remove that (usually don't). Exhaust manifold gaskets are reusable.

 

Timing component kits I usually get aftermarket as bearings are generally just as good as OEM. . . and they're hella cheaper. OEM idlers are $100 each sometimes, you can get a complete component set with tensioner for not much more. I do run OEM timing belts tho. . . just because.