Timing flywheel lock pin

Glsons · #1 04-21-2020, 04:46 PM

I could use some help. I have all four cams locked into tdc position. (All cam marks pointed in the upright position) Timing marks on timing chain cover matches crank dampener/pulley perfectly. Trying to remove the "Jesus bolt" and there's a small amount of play before the crank stops turning. Is there a possibility of the locking hole in the flywheel being "stripped" elongated? Sorry in advance for not being able to search through gads of pages, I can only use my phone currently and it's a pain to navigate the site on it.

Thank you, any help would be greatly appreciated.

TriX5 · #2 04-21-2020, 05:33 PM

To remove the "jesus bolt" I'd recommend getting the tool that bolts on to the vibration damper hub. To get the JB off I used that tool and a 3/4" breaker bar 24" long, even then had to stand with both feet and bounce for a bit to get it to move. To put that much torque through the crank shaft I am not sure is a good idea.

When I pin the flywheel there is no movement, odd if there is play.

Glsons · #3 04-21-2020, 06:07 PM

I just seen the hub tool that you mentioned. I may have messed something up. I have to now wait for the rain to stop before I can double check it. Need to see if I can get a look at the flywheel through the inspection hole near the lock tool. The lock pin itself is perfect though and sits flush in there. Can easily be removed and reinserted. I just figured that that part would take damage before the flywheel would. I'll have to check and invest in that other tool you mentioned. I didn't even know that existed till you mentioned it. Thanks TriX5

oldskewel · #4 04-21-2020, 08:03 PM

If you can get the pulley locking tool, that would be best. Or some people have rigged / welded up a substitute.

But on the flywheel locking pin ... when I did this on my M54 (different vs. yours, of course), I found that when I first thought I was properly inserting the locking pin, I still had about 10 degrees of movement of the crank pulley. So it seemed I could rotate the crank +/- 5 degrees before it would hit a stop.

Knowing that did not make sense, I removed the pin, etc., cleaned things and re-inserted it and it went in another level deeper somehow. At this point, the free motion in the crank was less than one degree. Very weird.

I would not have thought it to be possible to get it incorrectly locked like that. Should either lock in solid, or not at all, but that's what happened.

But anyway, hopefully this quantitative (10 degrees vs. less than one degree) explanation lets you know whether your "small amount of play" may indicate a problem.

Luckily for me, I was working very slow and careful and did not apply torque when it was not securely locked.

I ended up using my torque multiplier to get the bolt off. Worked great for me. Here's the thread on that:
https://xoutpost.com/bmw-sav-forums/...t-removal.html

^^^ and there are some pics in there for a V8

andrewwynn · #5 04-23-2020, 01:20 PM

Quote:

Originally Posted by oldskewel

But on the flywheel locking pin ... when I did this on my M54 (different vs. yours, of course), I found that when I first thought I was properly inserting the locking pin, I still had about 10 degrees of movement of the crank pulley. So it seemed I could rotate the crank +/- 5 degrees before it would hit a stop.

Knowing that did not make sense, I removed the pin, etc., cleaned things and re-inserted it and it went in another level deeper somehow. At this point, the free motion in the crank was less than one degree. Very weird.

I would not have thought it to be possible to get it incorrectly locked like that. Should either lock in solid, or not at all, but that's what happened.

If the flywheel is similar to the M62 there are spokes with holes and plenty of places the pin could go through that aren't the right place.

I used a fiber optic inspection cam to pre align the flywheel and the pin dropped right in.

oldskewel · #6 04-23-2020, 03:22 PM

Quote:

Originally Posted by andrewwynn

If the flywheel is similar to the M62 there are spokes with holes and plenty of places the pin could go through that aren't the right place.

I used a fiber optic inspection cam to pre align the flywheel and the pin dropped right in.

Yes, agreed. Nice pic.

I do assume it is similar for the M62 vs. my M54. And the main point I was making there was that it might happen that you think the pin is in there solid and aligned, and for some reason the crank is moving +/- 5* before hitting firm stops. .... And if that happens, then do not proceed, because you are not IN properly.

Once you are in, there is hardly any motion at all of the crank, as you'd expect. Less than one degree total. Just a wiggle.

Luckily for me, I figured out early on that the main thing to aim for when doing the head gasket / top end rebuild was to not screw anything up. It's not that anything is hard to do, it's that there are so many things that are easy to screw up, with bad consequences.

So my doubt led me to re-try, etc., but it was not obvious at first. Could have been a real problem if I had torqued hard with it in wrong.

Glsons · #7 04-21-2020, 08:23 PM

Thanks oldskewel, that's about how much mine rotates before hitting the stop as well. Unfortunately, it can not go in any further for sure. The handle on the lock tool is butted right up against the housing so I know it's inserted as far as possible. I've used it once before and had no issues. I'll have a look at it ASAP and hopefully nothing is damaged. Waiting for my Vanos gears which are being sent out for a rebuild because I don't have the tools or the patience for that haha thanks guys. I guess I need to inspect it more. Mostly wasn't sure if a flywheel could/would strip or bend with that kind of pressure.

TriX5 · #8 04-21-2020, 10:32 PM

Stating the obvious but just in case: you are aware the TDC mark on the distribution cover is about 45 degr CCW from "dead north"? Furthermore, there is only one hole in the flywheel that matches the locking pin. Once it inserted there is practically no movement on the crankshaft. The pin fits the hole in the flywheel with only .1 or .2 mm of play. So it is nice and tight. If you can move the crank by "degrees" then something is incorrect.

EDIT: Checked this morning and there is a nice big square hole directly below where the pin inserted. Visible only if you take the stiffening plate off.

It is a good while back that I obtained the hub holding tool off ebay from a source in NJ for $130 I think. I know that with time and tools it can be fabbed but in the grand scheme it is not that much, given that it helps avoid a repair bill of several thousand. Maybe a member in the Southwest has one you can buy or borrow?

Below a picture of the tool.

andrewwynn · #9 04-22-2020, 09:38 PM

I made the crank holding tool out of two angle irons cut a notch so I could fit four bolts from the harmonic balancer. Cost: about $6.

TriX5 · #10 04-22-2020, 10:34 PM

Andrew, I agree, not difficult to make, in the 80s I made a tool like that from a flat steel bar for a 323i or a Golf, too long ago now to remember. I carried it in my toolbox for years until it wound up part of another project :-) When I started to work on the M62 motor I was commuting to Asia. Time was precious and buying a tool the better option.

For the M62 the torque required to undo the bolt from the crankshaft is unbelievable. At least in my case it was, the size of the tool I bought bears witness to what the expectation is......unlikely I will ever get to use it again.