1996 2.5L Timing Belt Change Questions

[wcb]

The Web is a wonderful source of info - but some of it is
contradictory, and some of it is just plain wrong. I don't want to
trust some wrong info as I prepare to change the timing belt on my 1996
Outback (2.5L) engine myself for the first time. With 218,000+ miles
on the engine, I think it's ready for a new belt (last one went on via
a dealership install at 110K miles). So, since this is a valve
interference design, I've gotta get it right the first time or nasty
consequences result. One of the things I've read online is that I need
to use some fancy Subie specific tools to hold the Intake and Exhaust
cams in place, especially on the left side, when I go to pull the belt,
or the valve spring pre-loading will rotate the cams into a postion
where the valves smack into each other and something either bends or
breaks. Is that really true in this engine, in the 1996 configuration?
The reason I ask is that I've found some additional info about the WRX
STi engine that makes no such claim - in fact it says that if you
rotate teh crankshaft until all the cams line up to their reference
marks, that is a valve neutral position and there's no spring loading.
Which is true??? The STi is the same 2.5L block, right?

Help to clear up my confusion, please? Thanks!!

 

[Carl 1 Lucky Texan]

The Web is a wonderful source of info - but some of it is
contradictory, and some of it is just plain wrong. I don't want to
trust some wrong info as I prepare to change the timing belt on my 1996
Outback (2.5L) engine myself for the first time. With 218,000+ miles
on the engine, I think it's ready for a new belt (last one went on via
a dealership install at 110K miles). So, since this is a valve
interference design, I've gotta get it right the first time or nasty
consequences result. One of the things I've read online is that I need
to use some fancy Subie specific tools to hold the Intake and Exhaust
cams in place, especially on the left side, when I go to pull the belt,
or the valve spring pre-loading will rotate the cams into a postion
where the valves smack into each other and something either bends or
breaks. Is that really true in this engine, in the 1996 configuration?
The reason I ask is that I've found some additional info about the WRX
STi engine that makes no such claim - in fact it says that if you
rotate teh crankshaft until all the cams line up to their reference
marks, that is a valve neutral position and there's no spring loading.
Which is true??? The STi is the same 2.5L block, right?

Help to clear up my confusion, please? Thanks!!

If no satisfactory answers arrive here, please search/post at the Forums
on www.usmb.net

It may very well be that the practice of creating the marks has changed
and older engines may still be a concern as to cams shifting. There also
are books with incorrect torque value for the crank pulley as well as
some possibly confusing timing marks. There may also be a very good
reason to check/replace several other items in that area including the
water pump, maybe rebuilding the oil pump, etc.

carl

 

[Edward Hayes]

Look to www.endwrench.com for your answers and pictures.

 

[Michael Pardee]

The Web is a wonderful source of info - but some of it is
contradictory, and some of it is just plain wrong. I don't want to
trust some wrong info as I prepare to change the timing belt on my 1996
Outback (2.5L) engine myself for the first time. With 218,000+ miles
on the engine, I think it's ready for a new belt (last one went on via
a dealership install at 110K miles). So, since this is a valve
interference design, I've gotta get it right the first time or nasty
consequences result. One of the things I've read online is that I need
to use some fancy Subie specific tools to hold the Intake and Exhaust
cams in place, especially on the left side, when I go to pull the belt,
or the valve spring pre-loading will rotate the cams into a postion
where the valves smack into each other and something either bends or
breaks. Is that really true in this engine, in the 1996 configuration?
The reason I ask is that I've found some additional info about the WRX
STi engine that makes no such claim - in fact it says that if you
rotate teh crankshaft until all the cams line up to their reference
marks, that is a valve neutral position and there's no spring loading.
Which is true??? The STi is the same 2.5L block, right?

Help to clear up my confusion, please? Thanks!!

Haven't had the pleasure (?) on a Subie engine, but normally the TDC
position puts at least one valve on the flank of a lobe, which means the
cams don't normally want to settle there. It really isn't a problem with
single cams because the cam will tweak the crankshaft a bit so the cam is
happy, but DOHC nearly always settles off a bit.

I've never used a special tool, though. Usually I can get the cam sprocket
to stay in place with strategically placed wood blocks or similar "tools." A
popular trick is to make marks on the side of the original belt and onto the
sprockets to create match marks, using white paint or similar. When you
remove the old belt you transfer the marks to the new belt and make sure the
marks line up when it all goes back together.

Mike

 

[wcb]

Thanks Mike, Ed and Carl!

I found the EndWrench site shortly after posting my question earlier
today, and they have a great service article loaded with high
resolution pictures about changing the timing belt on the 2.5L engine,
telling me that indeed the left side (driver's side) cam is loaded by
partially open valves when in the cam belt alignment position. So I
will fashion a tool to do the job, either a block of something
relatively soft to wedge between the teeth of intake and exhaust cams
or something (such as a pair of sockets which I will bolt to a steel
plate) that can capture the hex bolts on each sprocket. Looks like
that should make the cam rotation a non-issue!

Carl, I am taking your advice, too. I am actually changing the belt
along with the water pump, since I can hear the bearing making noise
and I suspect it is only a matter of time before it starts to leak. I
had all the seals done with the last belt change, but I will definitely
inspect them and replace as needed. This car's gonna get to 300K
miles; of that I'm certain!

I appreciate the help, guys!

Wayne

 

[jerryeveretts]

I made the tool myself when I did mine, very easy. I hope this mental
picture works for you. I took two pieces of flat steel about 5" long
and 1" wide, and around 1/16" thick, welded them in an 'X" shape, then
I welded a nut right in the center, the size of the nut doesnt matter,
I used one around 15mm, then on the opposite side of the nut I welded 4
small (1/4") hex head bolts, these were welded sticking straight out,
in other words the heads were welded to the flat steel. now you have a
X with a nut on one side, and 4 pins if you will sticking out on the
other side, the pins (bolts) need to be welded so they will slip into
the holes on the cam pulley. then you stick a socket on the bolt and
you can torque the belt tension or whatever else you need to do.
Just remember you have to turn the crank 360 degrees after you do the
one side, I had a friend who just lined up all the marks, they will
line up even though one bank is 180 degrees out of phase!

Hope that helps!

Jerry

 

[Edward Hayes]

When the new belt is installed and the tensioner activated be sure to
turn the engine over by hand several revolutions and recheck to
alignment marks. That will confirm that all the belt/engine marks are
aligned. I found some marks appeared to be off about 1/2 a tooth so
inspect carefully while looking at the belt at right angles. The
factory belt comes with alignment white lines to assist. Ed

 

[Mickey]

The Web is a wonderful source of info - but some of it is
contradictory, and some of it is just plain wrong. I don't want to
trust some wrong info as I prepare to change the timing belt on my 1996
Outback (2.5L) engine myself for the first time. With 218,000+ miles
on the engine, I think it's ready for a new belt (last one went on via
a dealership install at 110K miles). So, since this is a valve
interference design, I've gotta get it right the first time or nasty
consequences result. One of the things I've read online is that I need
to use some fancy Subie specific tools to hold the Intake and Exhaust
cams in place, especially on the left side, when I go to pull the belt,
or the valve spring pre-loading will rotate the cams into a postion
where the valves smack into each other and something either bends or
breaks. Is that really true in this engine, in the 1996 configuration?
The reason I ask is that I've found some additional info about the WRX
STi engine that makes no such claim - in fact it says that if you
rotate teh crankshaft until all the cams line up to their reference
marks, that is a valve neutral position and there's no spring loading.
Which is true??? The STi is the same 2.5L block, right?

Help to clear up my confusion, please? Thanks!!

Never had a DOHC engine but on my SOHC when I changed the belt, the
replacement had timing marks that coincided with the timing marks on
the crank and cams. If you find a belt like this it could be of help
to insure proper timing.

Mickey

 

[Remco]

The Web is a wonderful source of info - but some of it is
contradictory, and some of it is just plain wrong. I don't want to
trust some wrong info as I prepare to change the timing belt on my 1996
Outback (2.5L) engine myself for the first time. With 218,000+ miles
on the engine, I think it's ready for a new belt (last one went on via
a dealership install at 110K miles). So, since this is a valve
interference design, I've gotta get it right the first time or nasty
consequences result. One of the things I've read online is that I need
to use some fancy Subie specific tools to hold the Intake and Exhaust
cams in place, especially on the left side, when I go to pull the belt,
or the valve spring pre-loading will rotate the cams into a postion
where the valves smack into each other and something either bends or
breaks. Is that really true in this engine, in the 1996 configuration?
The reason I ask is that I've found some additional info about the WRX
STi engine that makes no such claim - in fact it says that if you
rotate teh crankshaft until all the cams line up to their reference
marks, that is a valve neutral position and there's no spring loading.
Which is true??? The STi is the same 2.5L block, right?

Help to clear up my confusion, please? Thanks!!

I just did my daughter's a month or so ago.
This procedure may come in
handy:http://endwrench.com/pdf/engine/FtTimingBeltReplaceF00.pdf

Remco