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Removing head bolts

Featured Replies

I am trying to remove the head bolts. I have a 3/8" drive breaker with 2' 3/4" blk pipe cheater with a 14mm 12 pt socket. Using a lot of torque to remove, feels like the bolts are frozen. Don't want to snap them. Any idea's for help would be appreciated.

They are tough.

 

Helps to have someone hold the engine stand if possible. I jamb it against my lift so it can't move.

 

Those puppies will creak when coming out (and some will going in it seems no matter how well lubed).

 

Read the Endwrench procedure for the order. I have a hunk of cardboard for each head to keep track of their positions. On some heads they say that isn't necessary. I figure it can't hurt anything.

 

I use a 1/2 longer breaker bar. I'm not a guy who works out but I'm 6'2" and about 235 and not a couch potato. Them puppies are on there - as they should be. Often they are tight for a few revolutions. I ALWAYS run the bolts in and out with no air tools. I want to feel any resistance. Again a personal preference - there are a lot of threads.

 

Don't forget you'll be re-installing them to the same torque and trying to pay attention to partial revolutions in the long installation sequence.

  • Author

Advice and experience much appreciated, thanks.

 

Are those torque to yield type bolts? One local auto parts mechanic said they are, the guy at the dealer said they are not.

  • Author

Man alive those are on there. With that much torque, wonder why Subaru used a 12pt instead of a 6 point. The darn points are getting worn, the socket keeps coming off the end of the bolt. I may be in trouble here.

First - use a good quality socket.

 

Second - I use a long breaker bar. This lets me keep one hand on the socket/breaker bar head and the other on the handle. You may need a cheater bar in order to get the needed leverage with one hand on the handle.

 

I always have the head I'm working on at the top position on the engine stand.

 

I've never had an issue with the socket coming off. But if you look at the bolt head's shape, add in the torque you need to apply, you can see a potential problem that's why I put a hand there. When installing the new HG's and torqueing then down in certain steps it's tough since for most torque wrenches to be accurate you're supposed to have both hands at the end of the handle. When you get to the loosening and tightening by fractions of a turn I go back to one hand on the head of the breaker bar(since the torque wrench is no longer used - atleast by me). Things are getting pretty tight by then.

 

Why a 12 point? Why else would anyone buy a quality 12 point set I guess.

 

VW does the same on some things. Like the 2.0 Crank bolts. Hey - atleast it's not a "specialty tool" - read $$$

 

Good luck.

Edited by davebugs

OK, here it goes in the best order I can. (assuming a single cam?)

front:

radiator fans, and belts (tip) Take a 22 mm socket 1/2 inch- on a

breaker bar, put it on the crank bolt and tuck the breaker bar on the

car frame by the battery. turn key, listen for thump. check to see if

crank bolt is loose. timing belt and pulleys, remove covers from rear

of pullies. 1 10mm bolt for the dipstick tube and 3 14mm bolts holding

the lower ac bracket to the head-

drain rad.

Mostly bottom:

unplug o2 sensor by rt ft axle, unbolt the exhaust manifold from the

head, cover both with baggies. Unbolt aft exhaust bolt and drop out of

the way- you may elect to remove the exhaust pipe at this time -2 more

bolts by the transmission. remove two bolts on the engine mount.

Top:

air filter and all boxes, battery, washer tank. rear support rod.

Remove the two 10mm bolts on the right intake manifold that hold the

power steering lines down, bend the lines up about 1/2 an inch or so-

create room. unbolt the 8 bolts holding the intake manifold down,

also, remove the egr tube from the left head and intake.manifold (on

some cars) Pull up in the intake manifold and use something (we use

2x2's) to hold it "up"

Jack engine and somehow push it to one side, I suggest to the drivers

side first- and pull the pass side head first. put some wood under the

eng mounts, safety. In the shop we can get it high enough to clear the

mount studs from the frame, and pushed over so that sometimes the

bolts isn't even over the holes- not as easy to do on a auto trans.

Rt head:

There is a ground wire on the rear of the pass head, un-plug it.

Valve covers, 6 head bolts. You will need a 13mm 12 point socket,

preferably a 3/8 adapted to a 1/2 breaker bar; loosen the head bolts.

some may not be able to remove from the head because they will hit the

frame, but remove the ones you can. wiggle the head and remove it from

the bottom. coolant will come out, this is why you covered the exhaust

manifolds if you did not remove them.

now shift the eng to the pass side as far as it can go.

left head:

unplug the cam sensor and unbolt the oil fill tube. two 10mm bolts

hold the transmission lines to the bottom of the head, remove the

bolts. this is why you have it safetied up.

it helps to undo the rubber hoses, but it will leak trans fluid.

there is a hose clamp by the t-stat. it points toward the tire; pinch

it and turn it forward, it may be in the way when you wiggle the head

out.

unbolt the valve cover and remove the head bolts. this side is a bit

harder to squeeze out, but it can be done.

 

Unless I forgot something, hour heads are now on the ground.

Edited by Qman

If this is a 2.2, then the bolts can be broken. If it is a 2.5, I've never broken one. They are in there tight and you will have a hard time with a 3/8 bar. Spent the money and buy a 1/2" bar and get a good socket. You will be spendingsome real money if you mess up the bolt heads.

 

The bolts are not, I repeat NOT torque to yeild. They do not have to be replaced. Many parts guys will tell you they are because the torqueing procedure is a torque to yeild procedure. Subaru dose not use replaceable bolts.

 

Above all, make sure you use the specified torquing procedure. If you do not, you will be doing a HG job again. Not fun.

 

Good Luck

  • Author

Sorry if I didn't explain better, this is a Outback 2.5L DOHC phase 1 interference engine.

 

I actually already have it all taken apart with the engine on the stand, my current dilemma is removing the head bolts. Everything has been been removed from the engine, I am trying to get the head bolts off. Davebugs summation is pretty accurate. So far I have used a 3/8" drive breaker bar with 30" cheater bar, impact (250ft lbs), 1/2 drive ratchet with 30" cheater. The only thing I got so far is the ends of the star head on the bolt are getting stripped from the socket slipping.

 

I only had bolts this stubborn once before separating a v8 from a c4 tranny, but that was 28 years ago.

make sure you are using a high quality socket. I use a craftsman socket and have never had one slip off. If you are keeping the engine flat, I would suggest that you turn the side that you are working on up so that the socket is pointing down. you may have to have someone hold the engine steady and then I use one hand on the socket to keep it down and one pulling at the end of the bar. They should come out as these don't get corroded like the 2.2's do. I wonder if someone else did the HG's before and used locktite on the threads. If so, you may be screwed.

 

Never use an impact on the head bolts.

make sure you are using a high quality socket. I use a craftsman socket and have never had one slip off. If you are keeping the engine flat, I would suggest that you turn the side that you are working on up so that the socket is pointing down. you may have to have someone hold the engine steady and then I use one hand on the socket to keep it down and one pulling at the end of the bar. They should come out as these don't get corroded like the 2.2's do. I wonder if someone else did the HG's before and used locktite on the threads. If so, you may be screwed.

 

Never use an impact on the head bolts.

 

Mike - see my post#5 in this thread.

Good call dave. Maybe two of us telling him will help him out. I had seen your post, but I guess by the time I wrote that I had forgotten what you had said.

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