Ignition timing issue

[95Compact]

BTW, does anyone have a good way of getting a wrench/socket on that crank bolt? IIRC, that thing is a major biotch!

[95Compact]

Will do - I'll remove the belts, timing belt, etc and try to take it all off the crank...

I was thinking that if I can at least get it tight so it doesn't shift while the engine is running, I could just 'adjust' the timing belt the correct number of teeth - at least it'll be a lot closer than it is now.

I'm not going to go through the expense/time of replacing the crank if its shot though...

[TominMO]

TominMO, did you look at the pics I posted earlier? Maybe I'm missing something, but all looks right to me... check out the dizzy pics - these are all taken at #1TDC.

I don't doubt that the PO's 'mechanic' did something completely wrong - the little thing was a wreck when I got it- valve timing off a tooth, valve lash horrendous, etc...

I like your idea about installing the rotor 120deg clockwise, but I'm pretty sure its where its supposed to be (as in the flat of the trigger wheel is positioned towards the cylinder it is firing).

Finally found my manual and double-checked everything there... I agree its all relative alignment, but I'm still stumped as to whats off...

I've got her warming up now for another ignition timing check, I forgot to also remove the LOWER vac advance hose when I checked it yesterday...

OK; I was concerned that the rotor pic was not taken at #1 TDC, but you confirmed that.

THATS it!

Sure enough, the timing belt is properly aligned between crank gear and cam gear, but the crank gear is about 4teeth off the TDC mark when cyl#1 is actually at TDC...

Not surprisingly, this amounts to about 25-35 degrees of rotation...

So, now what?

Pull spark plugs and timing belt covers
with car in gear, push car until crankshaft sprocket mark faces mark on block
loosen timing belt tensioner and pull timing belt off camshaft pulley
rotate camshaft pulley to proper position (12 and 3 marks)
reinstall belt, tighten tensioner
make sure crank sprocket is still aligned!
install spark plugs (timing belt covers optional)
check ignition timing and adjust disty as needed; probably will have to retard the ignition initially from the full-advance position you now have it in

To get a wrench on that crank bolt, you will probably need to drop the motor on that side--i.e. loosen pass. side motor mount bolts until motor comes down. You would also have to remove the little black plastic splash shield. BUT, if you rotate the motor to where the crankshaft sprocket mark is facing up, by putting the trans in gear and pushing the car (with spark plugs already out so there are no compression issues), you will not even need to touch the bolt. All adjustment should be doable at the camshaft end.

[95Compact]

Ok, crank pulley/gear assy out... wow!

I'll post some pics on a minute, the crank keyway is $%*ed (sorry, 'screwed'), but the 'gear' and main bolt are fine...

Hang tight

[95Compact]

Ok guys, its fixed!

Pulled the crank gear, pulleys, etc - the key was all mangled (I'll post some pics tomorrow)... anyways, I reinstalled and tightened everything and then set the valve timing AFTER running it for a few minutes to ensure that the slop in the crankshaft keyways had preloaded fully...

So, then I repositioned the crank to TDC using a wooden dowel in the #1 plug hole, and set the timing belt so the cam was correctly aligned (at the marks).

Reset the ignition timing (now near the middle of the disto adjustment range) and had a drive - wow! What a difference!

She's running great now and I really appreciate all of y'alls quick and thoughtful help.

Cheers

[TominMO]

Fantastic! Great to hear.

[kartracer46]

Ok I read all that, glad to hear it's fixed. Next time just get a hold of me, I live in Raleigh and would be glad to assist you.

Sorry I caught this thread so late.

[FestYboy]

wow, wouldn't have thought the crank keyway would have gone south... i knew that was an issue with the B6s.

now for some pix!

[95Compact]

Yeah, its quite amazing! I think the majority of the damage was from running the engine with the crank pulleys slightly loose for a long time... check out this key (its about 5mm square):

[95Compact]

Well, unfortunately after driving the Festy a few miles for well-deserved beer run (don't worry, guys I drank a few for you too!) the crank pulley is wobbling again... going to have to figure out a way to secure this...

The problem is definitely not limited to Mazda's - I recall an ex-GF's '88 Supra developed a similar problem - actually, the crankshaft bolt hole threads stripped on that one (probably a bad mechanic there).

At least on mine, the bolt and hole threads are good (as far as I can tell), so it leaves a little room for 'improvisation'

[TominMO]

Well, unfortunately after driving the Festy a few miles for well-deserved beer run (don't worry, guys I drank a few for you too!) the crank pulley is wobbling again... going to have to figure out a way to secure this...

The problem is definitely not limited to Mazda's - I recall an ex-GF's '88 Supra developed a similar problem - actually, the crankshaft bolt hole threads stripped on that one (probably a bad mechanic there).

At least on mine, the bolt and hole threads are good (as far as I can tell), so it leaves a little room for 'improvisation'

Someone mentioned JB welding it. If you are gonna do a swap anyway, that would be a way to go to maybe make it last until the swap.

[Festy46]

In the picture of the key, was the good square end toward the block or toward the outside when you removed it? I think the last guy that installed the key put it in backwards if the square end was toward the block. The crank keyway goes from full depth to no depth at the back end because of the type machining that was done. The key is tapered on one end to match this depth change when installed correctly.

[hotfordcat]

Loctite Blue on your crank bolt will stop the bolt from coming loose again.

[Movin]

From what I have seen JB did not fail, the ones who put it there
were not aware as you are the importance of having the gear
indexed correctly. Of course you know that if you do this only you
can remove and put it back, a repair shop will stop when they find that!!
If you use the JB clean and rough sand surfaces where possible. Warm
surfaces and keep them warm during cure time..then the beer

[95Compact]

"Festy46 In the picture of the key, was the good square end toward the block or toward the outside when you removed it? I think the last guy that installed the key put it in backwards if the square end was toward the block. The crank keyway goes from full depth to no depth at the back end because of the type machining that was done. The key is tapered on one end to match this depth change when installed correctly. "

- I don't know, because it fell out when I was wiggling the gear assy off the shaft...

One thing that concerns me is that when I've got the pulley back on the shaft, the outsides (end of shaft and bolt surface of pulley) do not line up - as in, the end of the shaft is still about 1/2" shy of (recessed) the outer surface of the pulley where the head of the crank bolt tightens... I wonder if this is right or something in the pulley assy is assembled incorrectly?

Basically what I'm getting at is that the key does not have full engagement in the pulley's keyway (the outer 1/2" or so).

"Movin From what I have seen JB did not fail, the ones who put it there
were not aware as you are the importance of having the gear
indexed correctly. Of course you know that if you do this only you
can remove and put it back, a repair shop will stop when they find that!!
If you use the JB clean and rough sand surfaces where possible. Warm
surfaces and keep them warm during cure time..then the beer "

- This comment has been ignored because of the 'THEN the beer' statement...

Just kidding, lol! I'm wondering if the JB Weld could 'reform' the crankshaft keyway so that there won't be any shifting to loosen the crank bolt again... On the other hand, I was thinking that since the engine only rotates in one direction - with the timing belt only pulling in one direction (trying to rotate the cam gear CCW on the shaft, that is) - I was figuring that once the 'slop' was taken out, it would just stay where it was and not want to wiggle back and forth... But I guess that was wrong

As far as a shop not working on it - no one touches my private parts :nonosorry, my cars I mean) except me, so this is not an issue!