Real Time Help.......timing belt question?

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So....put my timing belt on yesterday, everything lined up (lines at both cam sprockets and at crank) see pics below.


Belt2.jpg

Belt3.jpg



Had little trouble getting the crank trigger and balancer on as both went on quite tight was fairly certain I got the balancer on fully seated. Went two full revolutions to check the timing belt alignment and all looked good.

Alignment after two revolutions:

Belt4.jpg


I had left it there last night and went to put the final torque on the balancer bolt this morning. I attached the holding tool to the balancer and started to tighten the bolt and the balancer looked like it moved. So I got off of the bolt and just tried to turn the balancer to see if it was in fact turning. Indeed it moved about 3/8" before the belt and Cam Sprockets moved! So I pulled it off.

I don't see how the belt itself could have gone anywhere but I want to check that relationship before trying to re-seat the balancer.

Question: If I turn the crank a few revolutions will the belt and corresponding marks ever reach a point where they are all lined up again so I can be sure the belt didn't somehow slip?
 
So....put my timing belt on yesterday, everything lined up (lines at both cam sprockets and at crank) see pics below.


View attachment 2499275
View attachment 2499277


Had little trouble getting the crank trigger and balancer on as both went on quite tight was fairly certain I got the balancer on fully seated. Went two full revolutions to check the timing belt alignment and all looked good.

Alignment after two revolutions:

View attachment 2499280


I had left it there last night and went to put the final torque on the balancer bolt this morning. I attached the holding tool to the balancer and started to tighten the bolt and the balancer looked like it moved. So I got off of the bolt and just tried to turn the balancer to see if it was in fact turning. Indeed it moved about 3/8" before the belt and Cam Sprockets moved! So I pulled it off.

I don't see how the belt itself could have gone anywhere but I want to check that relationship before trying to re-seat the balancer.

Question: If I turn the crank a few revolutions will the belt and corresponding marks ever reach a point where they are all lined up again so I can be sure the belt didn't somehow slip?
The marks on the belt are irrelevant except when first installing the belt. What matters is when the crank is at 0, both cams are at their marks. The belt marks probably line up again eventually, but I’d guess that’s like looking for a needle in a haystack.

I’m not sure what you mean by the “crank trigger”. Also, I assume your reference to the “balancer” = crank pulley?
 
Question: If I turn the crank a few revolutions will the belt and corresponding marks ever reach a point where they are all lined up again so I can be sure the belt didn't somehow slip?
Answer is Yes you can re-align them (the marks) again like how it looked like when you installed the belt. The answer as to ‘how many revolutions’ before you get it all lined up again is definitely more than 2 full revolutions on the crankshaft.

Looking at the picture you posted you are in the right track 👍🏼
 
The marks on the belt are irrelevant except when first installing the belt. What matters is when the crank is at 0, both cams are at their marks. The belt marks probably line up again eventually, but I’d guess that’s like looking for a needle in a haystack.

I’m not sure what you mean by the “crank trigger”. Also, I assume your reference to the “balancer” = crank pulley?

Crank Trigger/Crank Angle Sensor......................Balancer/Crank Pulley.

Yes when I first checked....the Crank 'Pulley' was on Zero and both marks on the Cam Sprockets were aligned with the marks on the housing (as per the pics).

I installed a new tensioner and the belt is quite tight so I don't see how it would have slipped. When I go the crank pulley installed yesterday it looked to be fully seated but the pulley only engages about 1-3/8" of the crank shaft and a mere 3/8" of the woodruff key.

I gave the bolt a quick 'blip' with my impact yesterday before making the two revolutions. Then was going to bring it to full torque this morning. It definitely moved before turning the timing belt so maybe I wasn't fully on the keyway?
 
Answer is Yes you can re-align them (the marks) again like how it looked like when you installed the belt. The answer as to ‘how many revolutions’ before you get it all lined up again is definitely more than 2 full revolutions on the crankshaft.

Looking at the picture you posted you are in the right track 👍🏼

Going to get to turning it then just to check and see that the belt didn't slip. If it checks out....then I guess I'll revisit why the crank pulley moved.
 
Going to get to turning it then just to check and see that the belt didn't slip. If it checks out....then I guess I'll revisit why the crank pulley moved.
I did the same thing just for insurance before the final assembly of all the components, I just forgot the exact revolution count before getting it all lined up again. But it did lined up again in respect to the belt getting tension from the hydraulic tensioner bearing post-pin removal.
 
Well l've rotated the engine probably 40 times now and the belt to pulleys alignment is constantly changing (as expected) but I've yet to get it all like it was before. The two marks on the Cam Pulleys will line up where they were before I pulled the old belt (advanced 50°) and the cogged pulley on the crank will go back the same position (I had made a witness mark). Those three things match up and I can achieve that over and over so I'm guessing its still in time.

When I removed the crank pulley....the keyway on it and the woodruff key on the crank were both at about the 3 O'Clock position and that is where it is right now with the cam pulley marks both back where they were before.

So any thoughts what to do from here? I'd love to see the belt and all other marks line up again, but I'm getting mighty tired of turning that engine.

Belt2.jpg


keyway.jpg
 
As long as the cams and the crank show TDC together every 2 revolutions of the crank, then you are good. Install like you have but once you start turning things over, forget the belt. I like to put the lower timing cover on, put the pulley on, tighten the crank pulley bolt and then check timing for the final time.

- In your photos, orange marks match up on your cams and the housing behind at TDC. (1 revolution here)
- The tick mark on the balancer/crank pulley matches the 0 degree mark on the lower timing cover like below. (equals two revolutions here)

IMG_6558.jpg
 
I remember worrying about this when I did mine. I hand cranked quite a few times expecting the belt markings to line up again with the timing marks. Never happened, but the crank and cams lined up so I sent it. Just more affirmation that you should be good.
 
I remember worrying about this when I did mine. I hand cranked quite a few times expecting the belt markings to line up again with the timing marks. Never happened, but the crank and cams lined up so I sent it. Just more affirmation that you should be good.

That's what I'm going with. Double checked and cams and 0 mark on the cover/crank pulley are all aligned as they should be.

I think it was just the movement of the crank pulley this morning that had me concerned. But....the crank has to turn twice for each revolution of a camshaft so the movement I saw before the cams began to move made me think it was slipping. I reinstalled the crank pulley and looked to see that it lined up with the pulley on the A/C compressor so I'd know it was fully seated (having to tap my pulley on). Got it torqued down and then moved the pulley back and forwards about 90° each direction and everything matched up fine each time.

Putting the other items back on now.

Thanks to all for quelling my fears. When you get to be my age....you have days where you doubt yourself sometimes (and that's unusual for me). ;)


Edit to add: It's a fool's errand to rotate the engine looking for the belt marks to ever line up again. No doubt it would happen sometime before Halley's Comet returns and it makes for a good workout, but DON'T DO IT.
 
Edit to add: It's a fool's errand to rotate the engine looking for the belt marks to ever line up again. No doubt it would happen sometime before Halley's Comet returns and it makes for a good workout, but DON'T DO IT.
Yeah, which is why said so above!
 
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Glad you got it- so easy to overthink it when one small mistake can cause big problema’s.

The 50degree after TDC method is prone to cause confusion- The 04 FSM and My 05 FSM doesnt have that procedure listed. Getting it right isn't an exact process either vs setting crank at 0 and cams set to hash mark for tdc. Lock in the cams in that position and your good to go.
 
Glad you got it- so easy to overthink it when one small mistake can cause big problema’s.

The 50degree after TDC method is prone to cause confusion- The 04 FSM and My 05 FSM doesnt have that procedure listed. Getting it right isn't an exact process either vs setting crank at 0 and cams set to hash mark for tdc. Lock in the cams in that position and your good to go.

The 50° degree advancement (for my vehicle, different for others) was not a stumbling block for me. I understood the reason for that (positions valves such that they are less likely to move the cams because of spring pressure) and that the only thing matters is to correctly line up and route the belt.

I did that and then rotated the crank two revolutions and all the 'match marks' were correct. But the next morning when I went to put the final torque on the crank bolt.....I swear I thought I saw the crank pulley move what looked like 10° or more with NO movement from the cam pulleys. This made me think I hadn't fully seated the pulley on the crankshaft and engaged the woodruff key. I had trouble getting crank pulley off to begin with (had to pull it the whole way) so lining it back up when I couldn't just put it on by hand was tricky.

So...with THAT doubt in my mind, I optioned to pull it and check everything. I knew in my mind that the only relationship that matters is that of the timing mark on the crank pulley being at 0 degrees TDC and the cams at their respective marks, which they were. But I really wanted to see the initial alignment marks on the belt be correct as well just to satisfy my stubborn self.

I had used my impact to 'blip' the bolt slightly tight and feared maybe I had jumped a tooth or two on the belt....which turned out not to be the case and confirmation of that was staring me in the face each time I brought the crank around twice and looked at the cam positions.

Already down the rabbit hole (wondering if the belt would EVER line back up with all the marks) I began turning the crank. The belt marks and cam pulley lines are constantly changing and I made other marks on it to watch the advancement. But you'll die of old age before you get them to all align again....and it's all for naught anyway.

So for anyone still reading this: Don't second guess yourself, line everything up correctly, double check, install tensioner, rotate twice, check your marks and if good, go with it.

Or...keep after it like a fool, and when your biceps swell to about 18" and you can no longer use them because of Lactic Acid build up, quit....! :rolleyes:
 
Well guys, got it buttoned up, fired up, runs fine, no leaks BUT:

I've got a 'mystery bolt' left over and for the life of me can not see where it goes!

Any ideas?


Mystery Bolt.jpg
 
^^is that a 12mm head bolt? it can possibly be for either the water pump or fan bracket. What makes me curious is that its color black, usually the bolts in these area are galvanized finish (grey).
 
^^is that a 12mm head bolt? it can possibly be for either the water pump or fan bracket. What makes me curious is that its color black, usually the bolts in these area are galvanized finish (grey).

Yes. 12mm head, I had cleaned it up and painted it along with some other bolts. It's not for the water pump....I double checked all the holes in it. Pretty sure I didn't miss any on the fan bracket either. But's its too long to be for a cover of any type.
 
engine oil pump cover capscrew? not required to remove it for the timing belt job, but IIRC, I had the same one left over- likely to have it left over if not needed for reassembly. have a look for missing capscrews on the oil pump housing:
1605832148874.png
 

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