Timing belt installed backwards

[mp_cude]

So, I’m doing my timing belt, and it has become obvious to me that I installed it backwards. I haven’t started it and only have it partially back together. It’s not my first time, however it has been a long time. Will it run better, worse or inconsequential? Thank you!

 

[GVegasG]

Why not fix it since it is not too late?

 

[97 AZ LC]

Why not fix it since it is not too late?

Indeed, you should fix it. The peace of mind gained will be worth it.

 

[GTV]

X3. The process is fresh in your mind, shouldn't take long at all to correct it.

 

[mp_cude]

Why not fix it since it is not too late?

That’s a fair and understandable question. If it’s inconsequential, and there no need to fix it, I’m an extremely busy person. Without going into details, fixing it will set me back two days as I’m chipping away at it. I have about 30 minutes free a day to work on it…my thinking is this, I remember having cars in HS and a simple mild performance tune was to advance the timing. If that’s the case here (which I doubt), I’ll leave it. I already know I have to correct it, I’m in the grasping at straws phase

 

[bigredmachine]

im impressed that you were able to get the timing marks lined up with it backwards, with that being said i would redo it correctly. it may not run with the belt timed backwards so theres that as well

 

[Rhetoric]

Sorry you are busy, but fix it. You will be busier if you have to re-do it down the road as who knows what else it could lead to.

 

[beatle_bayly]

The fact you've used the marks on the belt to align it would mean (in my mind at least) that it is OUT OF ALIGNMENT! i.e. the engine valve timing is way out.

If, on the other hand you had ignored the marks on the belt and aligned the cams to the crankshaft via other methods, then it would be fine. The belts aren't 'directional' per-se.

So think of it this way; if the belt had no marks and the crank and cam marks align as per the book, then it's all OK (though might confuse a subsequent repairer)

 

[AlpineAccess]

Definitely flip it. You can get the tensioner pin back in by pushing down on the tensioner pulley

 

[medtro]

I remember reading someone on his forum did the same thing a while back. I don't recall anything bad happened. I would crank it a few turns manually and check the marking on crank and cam pulleys. If the pulleys stop at the right position for a few times, then I would just drive like that. If not, prepare to figure out the crank and cam positions and redo it again.

 

[2001LC]

Your engine will likely run, but will not be happy

It's always faster the second time. If your pictures, are point you stopped. It's only about 1 hour back in & out, to time correctly.

I'd set cams on the marks as you now have them. Remove tension, place in vice and re pin. Remove idler pulley. Set crank on hard mark. replace belt. Then replace idler pulley,. Then replace tensioner and pull pin.

Spin crank 720 degrees and recheck, that all 3 hard timing marks dead on.

BTW: If you forgot to seal the tensioner pulley bolt threads, now is your chance.

 

[white_lx]

The "Car Wizard" installs them backwards too!

 

[97 AZ LC]

To reset the tensioner - if you don't have a big vice you can use an 8 inch C-clamp (Harbor Freight $9) and a six inch long piece of 1 inch inside diameter PVC pipe (Home Depot). If you misplaced the pin you can use a 2 mm hex wrench.

 

[medtro]

So, I’m doing my timing belt, and it has become obvious to me that I installed it backwards. I haven’t started it and only have it partially back together. It’s not my first time, however it has been a long time. Will it run better, worse or inconsequential? Thank you!

Not sure I like the crank position in this picture.

 

[beatle_bayly]

Not sure I like the crank position in this picture.

And ultimately this is why I NEVER rely on markings on a belt for any engine. They are a sucker punch in the making.

 

[mp_cude]

I bit the bullet and corrected it this evening. It only cost me 45 minutes. I don’t have fancy tools, so I need the markings. Also, the belt markings are off 1.5-2 teeth when installed backwards. I’m thinking to compensate for any stretch of the belt? I can’t imagine the belt would stretch though.

 

[2001LC]

I bit the bullet and corrected it this evening. It only cost me 45 minutes. I don’t have fancy tools, so I need the markings. Also, the belt markings are off 1.5-2 teeth when installed backwards. I’m thinking to compensate for any stretch of the belt? I can’t imagine the belt would stretch though.

View attachment 3317355

View attachment 3317356

View attachment 3317358

Also, the belt markings "are" off 1.5-2 teeth when installed backwards. I’m thinking to compensate for any stretch of the belt?

You did not stretch the belt. I assume you meant "were" not "are"

The Toyota belt and Aisin kit belt marks. Always line up perfectly, with the 3 hard marks. But not always will the crank pulley mark, lined up with plastic #1 timing cover mark Which is one of the reasons, I use hard mark on crank sprocket, lined up with oil pump housing hard mark. I also test for proper timing, with hard marks. Before installing #1 plastic cover.

Looking at your picture, which is obviously before spinning crank to test. Its crank sprocket to belt marks, "should" be dead on as I pictured in above post #11 for you. But I can't see that with No. 1 belt cover on. So can't see if your off a tooth or not. The test is spinning crankshaft clockwise, 720 degrees. At which point, the 3 hard marks line back up. But the belt marks will not line up again, once crank turned 720 degrees. So you've not tested bases on your last picture. But you look okay.

I don't see the Timing belt cover spacer ("mouse door") or its gasket in. Make sure to install these, before install fan bracket.

If you did not seal ((precoated parts, (yellow circles)) threads of tensioner pulley (No. 1 Timing belt idler sub-assembly) bolt. You will have an oil leak. We also sometimes get and oil leak. If idler (No. 2 Timing belt idler sub-assembly) bolt not sealed. No 2 threads should not leak oil. But if oil pump has ever been removed, it may.

Make very sure, the wire loom housing the crank sensor and oil pressure sending unit wires. Is tucked behind fan bracket, before installing fan bracket.

This wire loom, is routed wrong in below picture. Wire housing loom should be routed behind fan bracket.

If routed wrong, as seen in above picture. Very high risk of cutting wires on serpentine (drive) belt.