Z24 timing chain, dizzy, oil pump and head.

[Hillbillybuddha]

I know all these parts work together set timing. The PO had changed the head gasket and I think he got the timing wrong, either with the chain or the oil pump. So I'm starting from scratch here.

I pulled the head and took it into the machine shop (the gallery was blown again and there was water in my oil) had the shop magnaflux, pressure test and resurface the head. The head was warped But that's fixed now.

The timing chain slipped while I was removing the head and the dizzy wasn't marked because I couldn't spin it far enough to set the timing correctly anyway. So I'm starting from zero here.

I have the original 1983 720 shop manual but I seem to be missing something. I've rebuilt a fair share of old Ford and Mopar engines, a few transmissions and a bunch of motorcycles But everything I've read so far on doing the timing chain requires having another part set properly, like the distributor.

Is there a good write-up on this or where should I start?

 

Thanks.

[datzenmike]

The oil pump and distributor drive have nothing to do with the timing chain or setting the cam timing. Two separate things driven separately from the crankshaft.

 

If your chain wasn't secured the tensioner probably fell out when the cam sprocket was removed getting ready to take the head off. If so, the timing cover must come off to set everything right.

 

So can I assume the head is still off? and the timing cover as well?

[Hillbillybuddha]

The head is still off, I'll be removing the timing chain cover on my next day off. I'll pick up a new timing chain while I'm at it.

To get the timing chain cover off, does the radiator come out first to make room or will I have enough room as it sits?

 

And thanks for clearing up the dizzy / oil pump thing. I was under the impression that in order to set the timing chain, you had to get the oil pump set to fit the dizzy at 1 on TDC. Or some such thing

[ggzilla]

Remove the radiator. It will make it much easier but even more importantly it'll help prevent damage to the radiator.

[datzenmike]

The distributor, oil and water pump have to come off the timing cover to get it off. You also have to see the front of the block to see what you're doing. Having the rad out is a good idea. Usually removing the front and a couple on the side, and loosening the other oil pan bolts will allow the timing cover to slip forward off it's dowels.

[Hillbillybuddha]

Awesome suggestion. I'll make sure to do that.

 

I'm sure I'll have some questions come Monday when I finally get a chance to get into it.

[Doctor510]

ASK ASK ASK  there is at least 300 years combined experience here, we've all made mistakes and can tell you what NOT to do.

Don't let yourself cut corners, it will bite you in the a$$ down the road.

[Hillbillybuddha]

Yeah, you guys are always great. I don't get to come to this forum very often because I'm usually tooling on my old TBird or my Plymouth Scamp but when I've got a question about my lady's 720 this is the first place go too. Truth is my girl (IvyRacer on here) is doing most of the work herself and I'm just there to make sure she doesn't mess it up to bad and brake a nut loose when I need too. And offer guidance but I needed guidance myself with the timing chain, but I guess that was mostly because I came in with a misconception about the oil pump and dizzy.

 

Thanks again.

[Hillbillybuddha]

Yesterday was so nice my girl decided we needed to spend some time at the river, as usual, she was right.

 

But that means I didn't get a chance to pull the timing cover yesterday but just got to it today. And, as anticipated, I'm back with a question. I've tried a quick Google without results, so,

 

How do you get that 27mm crankshaft bolt off? My impact wrench isn't budging it.

 

Thanks.

[Lockleaf]

I use an 18" breaker bar and a cheater pipe slid over it. I do it from the top of the engine bay. I take the fan off usually but it can be done with the fan there.

[84720FourWheel]

Fifth gear, some cinder blocks, a breaker bar and a cheater pipe.

 

Or breaker bar and tap the starter with the bar against the frame.

[datzenmike]

Set the arm of the 'cheater bar' against the passenger side frame, get it snug and then hit the starter. Naturally have the coil wires off.

[Hillbillybuddha]

Is the crankshaft bolt reverse thread? If I start the truck with the breakerbar, won't it tighten the bolt? Or have I been tightening the boule bolt this whole time :/

[datsunaholic]

No, it is not reverse threaded.

[datzenmike]

Is the crankshaft bolt reverse thread? If I start the truck with the breakerbar, won't it tighten the bolt? Or have I been tightening the boule bolt this whole time :/

 

Lefty lucy... Righty tighty

[Hillbillybuddha]

Ha. Of course. I was thinking of the breaker bar spinning when I should have been thinking of the bar as stationary and the bolt spinning.

[Hillbillybuddha]

Tried the thing with turning over the motor. Didn't work. Finally put my shop jack handle (3ft) over my cheater bar (2ft) over my breaker bar (22 inches) for probably 5 ft of leverage. Still took me hanging from it but it broke free.

I have to get to work now but I might have time to finish pulling it apart tomorrow before work. If not, it'll be Monday.

[Lockleaf]

That's usually how I do it. Jack handle over breaker bar, works like a charm.

[Hillbillybuddha]

Yeah, my normal cheater bar is a 2 ft long piece of lead pipe. That's usually enough. Not this time, took another 3 ft of Jack handle. That was one stubborn bolt.

[datzenmike]

I have removed over a dozen L and Z crank bolts by simply kicking the ratchet handle sideways. Pulling steadily you might require 200 ft lbs to break them loose but a sudden impact can easily exceed that for a shorter time. That's all it takes. I easily removed a crank bolt from an engine laying on the ground with nothing holding it in place. A cheater bar would have just flipped the engine over. A good solid fast kick, 'snap' and it was loose.

[Hillbillybuddha]

The first thing I did was use my impact; didn't budge. Then I tried the breaker bar and a big rubber mallet,still nothing. Tried that trick with the breaker bar and turning over the motor, couldn't believe it but still didn't budge. Finally took 190# of me hanging from 5 ft of cheater bar. Granted, I didn't try laying on the ground and kicking but at that point I'm just glad you guys were around with suggestions and I would have tried that kicking method had I thought of it. Regardless, I'm sure I'll have other questions soon enough.

[Hillbillybuddha]

Before I pulled the head, I got it to TDC but with all the trouble I had with removing the 27mm crank bolt, the 1st piston is no longer at TDC. The heads were pressure tested by the machine shop and are no longer set to TDC either.

 

How do I go about installing the head? How do I set TDC with the head removed?

 

Thanks

[datzenmike]

I loosen the crank bolt and the cam sprocket bolt before setting TDC.

 

 

How do I go about installing the head? How do I set TDC with the head removed?

Thanks

 

If you marked the chain to sprocket location, it won't matter if not on TDC. It will just go back together properly.

[Hillbillybuddha]

And if I didn't mark the chain to sprocket location? I didn't bother because I'm pretty sure it wasn't installed right the last time (PO did it and couldn't get it to time correctly- I couldn't get it to time correctly either)

 

Side note:Datzenmike, wish I could buy you a 12 pack for all the help.

[Hillbillybuddha]

So here's what I've done. I think this will work but I'd really like a second opinion before I start putting things back together.

 

Bottom end; I don't think is that big of a deal. I think that the piston is either up or down so I just have to make sure that the first piston is at the top of it's stroke. Right?

 

Top End: I reinstalled the cam sprocket bolt and turned the cam until the intake valve has opened and closed but the exhaust has not yet opened.

 

The intake cam lobe is at 5 o'clock and the exhaust cam lobe is at 7 o'clock. The "2" in the center of the gear is pointing up at 12 o'clock and the "2" on the outer rim of the gear is around 2 or 2:30.

 

I should be able to just put it back together now? Does this seem right?

 

I should mention that the cam locating pin is in the sprocket hole marked "2"