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Discussion Starter #1
Hi all,

I'm in the process of putting back the timing-belt and crank pulley after replacing the oil pump gasket, and I have question on the positions of crankshaft, crank pulley, and TDC. (see attached pictures)

After removing the crank pulley bolt and crank pulley (note: at this point I didn’t pay attention the white marking on the crank pulley), but prior to removing the timing belt,
• I turned the crankshaft aligning
o the front camshaft pulley to #1
o back camshaft pulley With Pointer
o TDC Mark On Tooth Of Timing Belt Drive Gear With Pointer (note: the gear’s key aligns perfectly with the TDC marking)​
• I marked the timing belt with a white marker on these marking so that I could transfer these marking to the new timing belt ensuring that nothing shifted.

Now putting them back, the marking of the timing belt matches the marking on the front camshaft pulley, on the back camshaft pulley and on the timing belt time gear.

However, when I try to install the crankshaft pulley, the white marking and the TDC marking are not lining up (i.e. the key groove and the white marking on the pulley are not aligned) (??).

Did I miss something?

Thanks!
 

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1. Smart to use the "mark the old belt and transfer method" as a double check. HOWEVER, if the belt has been replaced improperly before, you will end up with an error. Before I do a belt job, I always confirm the ignition timing is correct with a timing light or use a TDC finder tool in the #1 cylinder. Through the years, I found a few engines running one tooth off with no drastic performance problems. Of course, this won't help you now.

2. At this point, I would suggest that you install the damper/pulley snugly enough to allow you to rock the crankshaft back-and-forth while you confirm that TDC on the pulley matches the piston position.

3. I don't recall any Honda engine design with timing belt pulley marks offset from TDC, but some brands use them. This means that the cam pulley marks will line up at other than #1 TDC. I had a Subaru 4 cam motor freak me out that way.

Good luck.
 

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Discussion Starter #3
1. Smart to use the "mark the old belt and transfer method" as a double check. HOWEVER, if the belt has been replaced improperly before, you will end up with an error. Before I do a belt job, I always confirm the ignition timing is correct with a timing light or use a TDC finder tool in the #1 cylinder. Through the years, I found a few engines running one tooth off with no drastic performance problems. Of course, this won't help you now..

Yes - unfortunately, I have to make an assumption that the dealer did that. So, using my method, nothing should change.

2. At this point, I would suggest that you install the damper/pulley snugly enough to allow you to rock the crankshaft back-and-forth while you confirm that TDC on the pulley matches the piston position.

I have confirmed the TDC of front camshafts pulley, back camshaft, pulley, and the crankshaft (i.e. the key and the marking are lined up). My question is why on the crankshaft pulley the key is not lining up with the white marking. If I install the crankshaft pulley, the white marking will not be at the TDC position.
 

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Discussion Starter #4
Before I do a belt job, I always confirm the ignition timing is correct with a timing light or use a TDC finder tool in the #1 cylinder.

I've been thinking on your statement about timing lighting and the TDC marking on the crankshaft pulley (i.e. the white marking). My guess is that it is not exactly align with the key because it takes into account the delay of when the #1 cylinder reached the TDC, the timing light to be lit, and human eyes to see. If I'm right, it makes sense why the key is not lining up with the white marking but a few degrees to the left of the key as the crankshaft pulley turns clockwise.
 

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The white mark on pulley lines up with a raised line on lower timing belt cover. Once assembled look down to rear of lower cover and they’ll align.
 

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With everything set at zero degrees, TDC of #1, (like it shows in your pictures) if you temporarily place your lower, plastic belt cover on and slip the pulley on, the single white notch on the pulley should line up with a v-shaped tab on the cover. The tab is at about 11 o’clock. (The other 3 notches are your timing advance limits which can be checked against the V with a timing light with the engine running. Not necessary to do but it’s one way to check if the belt is off a tooth or more.)

Before you cover up the belt, good check is to rotate the crank by hand a couple times (with the pulley bolt) to make sure you have no interference between pistons and valves. All 3 timing marks should line back up when you get back to TDC of #1.
 

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Discussion Starter #7
With everything set at zero degrees, TDC of #1, (like it shows in your pictures) if you temporarily place your lower, plastic belt cover on and slip the pulley on, the single white notch on the pulley should line up with a v-shaped tab on the cover. The tab is at about 11 o’clock. (The other 3 notches are your timing advance limits which can be checked against the V with a timing light with the engine running. Not necessary to do but it’s one way to check if the belt is off a tooth or more.)

Before you cover up the belt, good check is to rotate the crank by hand a couple times (with the pulley bolt) to make sure you have no interference between pistons and valves. All 3 timing marks should line back up when you get back to TDC of #1.

Thanks for the input. Do you have any picture on this V-shape tab on the cover?
 

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Discussion Starter #11
I turned the crankshaft 2 rotations and all markings line up correctly. I also confirmed that V-shape tab on the cover does line up with the white marking on the crank pulley.

I think I'm good and ready to close up.

I learned that the crank bolt TQ spec is 181 ft-lbs. What is the best way to do this without turning the crank pulley?
Should I put the serpentine belt to hold the crank pulley and use the impact driver?

Thanks again!
 

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Discussion Starter #13
The crankshaft is very brittle, and is more prone to impact breakage than, for example, lug nuts and studs.[/url]
Thanks for the advice. I'm getting the tool. However, it is interesting that the crankshaft is very brittle as I loosen the crank bolt using the impact driver. Do you think the damage has already been done?
 

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I wouldn't get my knickers in a twist over it - let's face it, that crank survives thousands of explosion-driven "hammers" spinning it for hundreds of thousands of miles. Yes, I agree that an impact wrench might not be the right way to remove / install the crank bolt, but the torque (even the instantaneous impact) is MUCH lower than what the crank experiences normally. Also, I think it would take a HUGE impact wrench to generate the amount of force needed to get the typical Honda / Acura crank bolt loose. I took mine off by leveraging the "fixed" breaker bar against (IIRC) the lower control arm, and turned the "inside" breaker bar with a floor jack (so much easier than trying to find a place to get enough umph on the breaker bar). I'd bet there was 1000 foot/pounds of torque on the bolt before it started to move.


Tightening the bolt is kind of the opposite, only of course, at a much more "human scale" of torque required. I really don't remember, but am 90% sure I just used the crank bolt tool again, in reverse (it will effectively keep the crank pulley from moving in either direction, after all).
 

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RE: Crankshaft hardness. Removing the bolt with impact should not be a problem. The potential problem is on installation. The repeated impact blows transmit shock to the threads, and that is where damage might occur. Certainly the main body of the crankshaft would not be damaged with anything less than Industrial/HD Truck air tools.
 

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Bluepill, I agree entirely. With "only" 181 foot/pounds needed, there's no need to use an impact wrench (though of course, lots of folks will use 'em, including some "professionals" putting lug nuts back on... sigh).
 

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Re tools, if you’re close to an Autozone or Oreillys, they have loaner tools for the hex and 250lb torque wrenches.

I’m sure it depends on year but you might want to double check the torque spec. I’m not near my manual but for an 06, I recall it was something like torque to 20 or 45lbs, then mark the hex and turn an additional 60 degrees (1 hex flat). The threads and both sides of the washer were also supposed to be oiled so that the torque is applied correctly. I recall having to use the hex and my 5ft cheater bar to get the last 10-20 degrees. Anyways, don’t quote me - best to double check.
 

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The factory manual says to torque the crank pulley bolt to 47 foot/pounds, then turn it an additional 60°. No idea what the torque to do that would be, though I'm sure it's "quite a bit". ;-) I don't recall even doing it (though I'm certain I did), so I'm thinking it wasn't a really big issue (probably just did it with a regular breaker bar or torque wrench).
 

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No idea where this degree torque is from. The J series is 181 ft-lbs torque and drop engine oil on threads and between washer and crank bolt head.
 

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Torque spec looks like it depends on year.

FWIW, link shows the factory manual and torque specs/instructions. Same as Habby quotes and just confirmed my factory manual shows the same pages.

Haynes 01–07 MDX manual shows 181 ft-lbs for 01/02 Acura. For all others, the 47/60 procedure above. (Manual covers 01-07).

I don’t recall the OP’s year. I think it was in another post.

https://www.google.com/amp/s/www.mdxers.org/forums/74-second-generation-mdx-2007-2013/128810-timing-belt-torque-specs.html?amp=1
 
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