Jump to content
LegacyGT.com

Head Gasket Replacement Question(s)


Recommended Posts

Greetings everyone!

As long as everything goes as planned I’m going to replace my head gaskets next spring.

I will be using OEM MLS gaskets but I will be going aftermarket for any other gaskets needed. I just have a few questions.

Is it necessary to machine the heads? I only have an external oil leak and no coolant leak, so I would assume there is no warping?

Also what else should I replace while I’m at it? I will be removing the engine to do this job. I will be replacing the oil pan and gasket as well, because I have a rather large dent in the oil pan.

All help and advice is greatly appreciated.

 

 

Sent from my iPhone using Tapatalk

Link to comment
Share on other sites

Take a straight edge to your heads and measure warpage. All engines/heads have warpage, it just depends how in/out of spec it is. Typically Boxer motors have a 0.05mm warp limit for both heads and deck. Any more than that and it's going to need to be machined. Machining the heads isn't typically too bad. Depending on if you have the machine shop disassemble and reassemble the head means the difference between $ and $$$. If the block needs to be machined, expect for $$$$ if you don't tear it down yourself.

 

In terms of other items to replace while the engine is out, my advice is EVERYTHING. Every gasket, wear item, belt, and hose. Get a good complete gasket kit while you're at it.

 

Clean every nook and cranny of the block and heads then apply a fresh coat of high heat paint to it. Clean the engine cradle too, top and bottom. Trust me, it'll make things easier when you are trying to track potential leaks later.

 

Last, do not forget the rear main seal and the oil separator plate. You don't want to get everything back together and find that you didn't take 5 minutes to reseal the separator plate and rear seal and now you have to take the engine out again.

Link to comment
Share on other sites

You should measure the heads for flatness when they are removed and replaced. A good way to do it is using a machinists straight edge and a set of feeler gauges. If the gap exceeds specs in the FSM anywhere on the mating surface, the heads should be resurfaced. If not resurfacing, the heads need to cleaned and prepared to meet a spec for RA surface roughness.

 

While the engine is out, it would be good to replace the rear main oil seal. Also if your engine has the plastic cover plate (aka oil separator plate), replace with the metal version P/N 11831AA210 (may want to check that is correct) and fasteners. There are some o-rings on the wrist pin access holes on the rear of the engine. Intake manifold gaskets, exhaust header gaskets, valve cover gaskets.

 

If you are close to due on the timing belt service, do that with the engine out. You can replace cam and crank seals, reseal oil pump and water pump at the same time.

Link to comment
Share on other sites

You can buy a OEM master gasket kit for 300$+ probably the best option as it will come with everything you could ever need. https://parts.bestbuysubaru.com/ has some of the best prices. During the holidays they have 5% off and free shipping. My local dealer even prices matches them for me on 90% of items.

 

-Send the heads out to get check it is totally worth it. Most machine shops don't charge much.

-If it's manual it's a good time to do a clutch.

-The oil pan doesn't have a gasket. It's just rtv.

-Motor mounts are worth looking into also. a lot easier to take off with it on the engine stand.

Link to comment
Share on other sites

Thanks for the advice on the kit, I will look into it. My car is auto, I only wish it was standard. I was thinking about the motor mounts as well. They’ve been covered in oil for years I’m sure they could stand being replaced.

 

 

Sent from my iPhone using Tapatalk

Link to comment
Share on other sites

  • 3 weeks later...

Hey everyone, so new evidence has come to light. I am leaking coolant from my head gaskets as well as oil. I’m really considering just investing in the jdm 2.0. I can get it for $750 shipped on eBay. They provide pictures of the actual engines you receive and they look very clean, and are said to have less than 50k on them.

I really don’t need the extra power that the 2.5 has. I would prefer a reliable car over a slightly more powerful car. If I do go that direction, what are some things you guys would recommend? Will the oil separator plate also work on the 2.0?

 

 

Sent from my iPhone using Tapatalk

Link to comment
Share on other sites

The JDM 2.0 is pretty weak. Don't you live in the mountains, passing on 2-lane roads, etc.?

 

If you use the good head gaskets and do the job right you should not have to do that job again. The gaskets are the problem. Parts will be a few hundred dollars, so less than a JDM engine.

Link to comment
Share on other sites

I do live in the mountains, but it’s not like you think lol. Its not all up hill or anything. The roads are mostly flat, and there are very few places you can pass on a two lane.

Besides I don’t really have a reason to pass other cars lol. I drive fairly restricted, I barely ever go above the speed limit and my car always seems to have power to spare because I do not utilize it, if that makes any sense.

Also I’m not sure what the condition of the engine really is. It’s been leaking oil for probably 10 years or better, I’m sure it’s been run short a few times.

If I just replace all the gaskets I’ve still got heads and a block with 200k on them. By the time I add the cost of resurfacing the heads and block, I think I can easily exceed the cost of the new engine. I appreciate the input very much, I’ve not made up my mind yet and I’ll still listen to opinions and take everything into consideration.

 

 

Sent from my iPhone using Tapatalk

Link to comment
Share on other sites

Like I said, I haven’t made up my mind yet, I may not even keep the car.

However, $500 to $750 near me for a 2.5 is unheard of. There is a local junk yard that can get them shipped in from PA, but they are $1,000 a pop and have above 150,000 miles on them. There are a few junkyards in PA selling them for $700, but still above 150k. And I have no way to haul an engine really and I’m not sure I would trust the Subie that far.

As for the JDM 2.0 I know they have less power and less torque, I’m not really concerned about it. Before this Subaru I had a ‘99 Taurus which produced only 145 hp in a boat of a car. It was slow as hell. It could barely pass a tractor, but it didn’t bother me at all. I loved the car and the only reason I got rid of it is because my grandmother said I could come get this Subie and pay her when I get the money.

Also the body on my Car is in pretty bad shape, so I was actually hoping to put the JDM engine in, maintain it well and eventually put it in another Subaru, perhaps a 1st or 2nd gen Legacy or an Impreza Outback Sport or something like that, using my car for parts.

 

 

Sent from my iPhone using Tapatalk

Link to comment
Share on other sites

Wow I'm going to stop complaining that my local yard jacked up the price $75 and $40 more for a core on complete motors. I can get any motor from my local yard for $350 + $85 core charge. I can get short blocks for $150 out the door including the $25 core and long blocks for $223 + $45 core.
Link to comment
Share on other sites

  • 3 weeks later...

Hey guys, I’ve been experiencing an intermittent burning smell, mixed with a puff of blue smoke on cold start ups.

Seems to be happening one or twice a week, but it is a very strong burning smell and seems to be there as soon as I start my car. I don’t always pay attention but I’ve noticed a small puff of blue smoke occasionally too.

Any ideas? Piston rings?

 

 

Sent from my iPhone using Tapatalk

Link to comment
Share on other sites

1. do it right and send your heads off to a shop that deals with Subaru heads

2. make sure you don't pull your block threads out with your head holts

3. I would use new head bolts and lubricate them before install

4. use the latest gasket Subaru offers, do not use aftermarket

5. Follow Subaru's tightening sequence to the letter

6. might as well replace anything that is wearable that you can tale off the motor like crank seals, timing belt, water pump, etc

Link to comment
Share on other sites

  • 4 weeks later...

Hey everyone, I haven’t updated in a while but I’ve developed an external coolant leak(not sure if I’ve already mentioned that) and also this burning smell/blue smoke has progressed a lot. It now happens on every cold start and blue smoke comes from the exhaust for about 2 minuets. I’m no longer going to put any work in this car, I’ve got a couple grand in it already and the body is shot. Both quarters are rusted the rockers are starting to rust and the driver door is beyond fixing. So I will be buying something else soon and selling this pretty cheap. I was thinking about looking for a relatively clean 1st or 2nd Gen Legacy, but not certain yet.

 

 

Sent from my iPhone using Tapatalk

Link to comment
Share on other sites

  • 2 weeks later...

Got another update for everyone. I sold the Subie to some fellow for $500 yesterday. Sadly, I was unable to find another Subaru in the time frame I was given. I ended up buying an Explorer.

I want to thank everyone so much for all the help and advice. I will eventually own another Subaru, probably not a 3rd Gen though.

 

 

Sent from my iPhone using Tapatalk

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.



×
×
  • Create New...

Important Information

Terms of Use