Timing Belt Alignment Marks?

[codfizzle]

OK so I know this area has been covered quite well here, but I haven't seen somebody ask this particular question yet, so here it goes.

I'm putting a new timing belt on my car and here's the issue I'm having: I put my new belt on just like the manual says to do it, lining up all 3 marks on the belt with the marks on the sprockets and the sprocket housings, respectively. Then I rotated the engine by hand about 6 or 7 full cycles (by cycles I mean cranking until all 4 cylinders go thru the up and down strokes), but at no point did the marks all line back up the way they were.

All the manuals I could find say to rotate the engine so the #1 piston is at top dead center of its compression stroke before the job, right? And they also say to align the notch on the rear of the crank shaft sprocket (not the arrow stamped into the face of the crank shaft sprocket, which is 90 deg. to the right of the timing alignment notch) with the crank sensor boss so it is at the 12 o'clock position, right? So I pulled the plug on the No 1 cylinder and looked down the hole with a mag light while slowly cranking the engine by hand and was very conused by what I saw. When the No 1 piston is at top dead center of its compression stroke, it's the arrow stamped into the face of the crank shaft sprocket that's aligned with the crank sensor boss at 12 o'clock, not the proper timing mark at the rear! So the manuals say rotate to top dead center, but they also say to align the rear notch with the sensor boss, so which is it- because they are NOT the same!

Also a mechanic friend of mine told me that on every Subaru he's ever worked on, you can pull that rubber plug out of the engine side of the bell housing on top (so you can see the flywheel) and there's 3 hash marks stamped into the edge of the fly wheel; of which the middle mark is supposed to line up with a mark on the bell housing when the No 1 piston is at top dead center. I searched and searched and searched and never found any marks of any kind on the bell housing or the flywheel, so now what?

I think that you're supposed to start at top dead center, but when it comes time to align the belt marks, the crankshaft sprocket needs to be rotated 90 deg to the right so that the notch on the rear of the tooth aligns with the sensor boss. I think they just have you start at top dead center as a reference point when the shafts have been turned without the belt on; this way you're sure that you're within 90 deg or less of the proper timing marks. I'll try this and post results.

[juice91si]

what manual are you using?
i followed the steps in my hayes and had no trouble at all. it was actually pretty straight forward. line up marks on pulleys, timing covers, and proper belt teeth spacing and then put it back together. ran perfect.

your paragraph was so confusing to read so it makes understanding your problem difficult. i may just not have the patience to go back and read it over and over.

[kimokalihi]

He's right that was slightly confusing. Next time write in paragraphs not just a big block of text. Makes it much easier to read.

The unfortunate thing about message boards is that the least you write, the most responses you recieve and the more you write the less, if any. Which sucks because most of the time I need to ask a question is because I can't find it searching or it's complicated and a rare problem that needs a lot of explaining but nobody wants to read it all.

I am trying to figure out how to do the timing belt on my JDM EJ20 DOHC motor and it's baffleing me because I have a USDM haynes manual and it's showing a timing mark on the crank pulley yet there is none on this pulley and there is no mark on the GroupA lightweight pulley I bought. Also I don't know which cylinder is which and none of them seem to be at Top Dead Center when the cam marks are lined up!

[Legacy777]

The timing marks are not really going to line back up after you rotate things.

If you lined everything up correctly, you should be good.

[codfizzle]

Yeah sorry guys, sometimes I type like one of those long winded british poets where one sentence is a whole paragraph long.

kimokalihi: The middle timing mark is on the crank shaft sprocket itself,not the pully (there is a mark on the pully, but it is not used in lining up the timing belt marks). And don't confuse the arrow stamped into the front of the sprocket with the timing notch (which is on one of the bumps on the rear side of the sprocket)- these marks are 90 deg away from each other.

The No 1 piston is the one on the front passenger side of the engine, No 2 is on the front driver's side of engine, No 3 is on the rear passenger side, No 4 is on the rear driver's side.

I have also found that the timing marks don't line up when the No 1 piston is at top dead center, so I'm going to try a couple of different things right now, and I will post the results this afternoon.

P.S. Thank you Josh for that tidbit. I've never done a timing belt on a Subie before. Thanks!

[codfizzle]

OK so the job is done. Here's what I did:

Pulled the plug on the No 1 piston and looked down the hole with a flashlight so I could see the piston moving back and forth as I cranked the crankshaft by hand. Stopped when piston was at TDC. This aligns the arrow stamped into the front of the crankshaft sprocket with the alignment mark on the crank sensor boss. From there, I rotated the crank an additional 90 deg clockwise, which aligns the actual timing mark on the rear of the crankshaft sprocket with the alignment mark on the rear nub of the crank sprocket.

From there, install the belt making sure that all 3 lines match. Check your lines again once you've installed the tensioner and put tension on the belt. If you're still lined up at this point, you're golden. You can put your timing belt covers back on and install your crank pully and your accessory drive belts. MAKE SURE TO TIGHTEN YOUR CRANK PULLY BOLT TO AT LEAST 110 FT LBS, IF NOT MORE!

Changing this belt made a huge difference. I think the last person to do a timing belt job on my car lined the belt marks up with the wrong mark on the crank sprocket.

Before I changed the belt, the engine just felt gutless. I've driven other Legacies before, and I knew they're supposed to have more balls to them than that. Also, when I would be warming up my car before, it would get to running temp and then when it would idle itself down (to about 400 rpm) the engine sounded rough and there was a very noticable wobble to the whole car whenever the engine was below 500 rpm.

Now, ALL of that 2.2 litres of power is being utilized. Also, now when the car gets warm and idles itself down to 400 rpm, there is no wobble whatsoever and you can barely even tell that the engine is running.

[Fkyx]

Idle speed should be 750RPM, if I recall.

Thanks for the write up! I need to change my timing belt soon, also.

[kimokalihi]

90 degrees retarded I didn't think it would run if it was that far off! I thought the computer advances or retards timing as much as like 8 degrees or something.

I'm about to go out and start taking everything off. The timing belt, tensioner, idlers, oil and water pump and replace it all. I'm worried about the crankshafts turning independantly after I get the belt off. If they do turn somehow, how do I get them all where they need to be when I put the new belt on, which could be in a week or two weeks or in a couple days? Does it matter? Do I just line up the marks and it's good to go?

I did replace the belt on my last legacy but that was over 2 years ago and I don't remember it that well. Plus this is a DOHC motor.

[codfizzle]

The 2 cam shafts (1 on each side) can turn however much with the belt off, it will have no ill effects as long as you line up the notches properly during reassembley. The crank shaft in the middle is a little more picky. Refer to my above post about how to get the No. 1 piston to TDC and align the crankshaft notch from there.

[kimokalihi]

Alright, gotcha that's what I was thinking but I wasn't sure. For some reason I had it in my head that the cam shafts turn 720 degrees to get all the way back to the same point again. I got confused with the cam shaft turns 2 rotations when the crank makes 1 rotation. OK that makes me feel much more confident, almost 100% sure I know what I'm doing now.

Now I'm going out in the garage to tear into this thing. Then once I've got it all off I'm going to order all the cam seals, oil seperator plate, thermostat and gasket, intake gaskets, subaru key, and that damn water pump gasket that they don't supply you with when you buy the pump! GRRR! Why would they not give you the water pump gasket with the pump!?

[93Leg-c]

The No 1 piston is the one on the front passenger side of the engine, No 2 is on the passenger rear of engine, No 3 is on the front driver's side, No 4 is on the rear driver's side.

#1 cylinder is front passenger side
#2 cylinder is front driver side
#3 cylinder is rear passenger side
#4 cylinder is rear driver side

[codfizzle]

The No 1 piston is the one on the front passenger side of the engine, No 2 is on the passenger rear of engine, No 3 is on the front driver's side, No 4 is on the rear driver's side.

#1 cylinder is front passenger side
#2 cylinder is front driver side
#3 cylinder is rear passenger side
#4 cylinder is rear driver side

Yeah sorry, I got confused thinking about the firing order because the firing order is 1-3-2-4, but you're definitely right about the piston numbers. Thanks!

[93Leg-c]

YW!

[Fkyx]

Okay so I started tearing into the front of my engine today to replace the timing belt. I have a few questions after a quick look at the situation.

So I put the #1 piston at TDC, as per the manual's instructions. When I took the timing belt cover off, I noticed the arrow on the crank sprocket wasn't pointing straight up. It was a few degrees clockwise from straight up.

I then proceeded to turn the crank CLOCKWISE until the white marks on my camshaft sprockets and crank sprocket humps "lined" up with their respective notches. I stopped there. Firstly, is this correct?

Secondly, here's a drawing of what I saw:


The camshaft sprocket marks are lined up with their notches, but it appears the crank sprocket isn't. What do I do about this?

In case this means something... I decided to change my timing belt because of a pretty bad "piston slap" that turned up after driving my car pretty hard. I figured the timing may be off a tad.

Any help is greatly appreciated.

[RJ93SS]

that's why you got piston slap i'd assume, all three lines should be lined tdc, clean your crank sprocket so you can properly see the lines

[Fkyx]

I can see everything on the sprocket. But as I understand, you're supposed to line the "hump" on the plate behind the sprocket with the notch on the oil pump. Is this not correct?

[kimokalihi]

That is correct. I had a similar problem when I lined mine up. I had the crank sprocket lined up. The piston was not all the way up to TDC for some reason. The driver side cams were lined up and the passenger side cams were off probably a tooth.

Does this mean there was cam damage or any other damage? Should I take the heads off and inspect them? This worries me.

This is on a JDM 2.0 EJ20H twin turbo DOHC motor.

[Fkyx]

Could definitely use some help on this subject. lol

[Legacy777]

You don't need to do squat for TDC. Just align the marks and put the belt on.

Here are pics of how things should look.

www.main.experiencetherave.com/subaru/images/timingbelt

[ultrasonic]

For EJ22t...

[SemperGuard]

Also a mechanic friend of mine told me that on every Subaru he's ever worked on, you can pull that rubber plug out of the engine side of the bell housing on top (so you can see the flywheel) and there's 3 hash marks stamped into the edge of the fly wheel; of which the middle mark is supposed to line up with a mark on the bell housing when the No 1 piston is at top dead center. I searched and searched and searched and never found any marks of any kind on the bell housing or the flywheel, so now what?

Your friend has only worked on Subarus with distributors.

[codfizzle]

That makes sense. Thanks for clearing that up.