Bringing a 1977 Z back life

[Av8ferg]

I found this on the Zcar forum.  Seems to pertain to my issue.  Sounds like I need to pull the oil pump and make some alignment adjustments.   Not sure how to do this but I’m looking now how in the FSM.  

http://www.zcar.com/forum/10-70-83-tech-discussion-forum/285669-distributor-rotation-timing.html

[Zed Head]

2 hours ago, siteunseen said:

Another thing ive read of on here is to be sure the driver's side of the chain stays tight. Don't roll it back. If it gets slack it messes it all up.

I rolled mine 42 miles 4 feet at a time.

 

I was thinking of that this morning but my brain was locking up on it.  You're right, that could be the cam timing problem, why the notch and groove are off.  The way to tighten the chain, to check, would be to put a wrench on the timing chain sprocket and turn it back (counterclockwise, standing in front of the car) until the chain is tight on the driver's side, but not far enough to move the timing mark on the pulley.  Try to move the notch back under the groove.  Don't worry about the bright marks on the chain, they are only for the first installation.  The notch and groove are all that matter now.  I would confirm that the chain is tight on the driver's side, and see where the marks are, before worrying about resetting the sprocket.

Captain Obvious @Captain Obvious wrote up a simple way to get the pump and dist shaft right, using a method to hold the distributor drive shaft up in the hole so that you only have to match it with the oil pump.  I think that there were rubber bands involved.  I've used the small skinny nose Vise-Grips before.  Your plug wires were set  to match the oil pump being in the wrong spot.  Seems like the PO might have mis-adjusted a lot of things.

Since you're in there, and there's so much gunk under the valve cover, I would remove the spray bar and clean it out with carb cleaner.  Make sure that all of the holes are clear.  One for each lobe.  Maybe turn the engine over and make sure oil comes out of the supply hole.  Cover it with a rag first.  With the plugs out and the motor spinning you should get plenty of oil.  When you have the pump off to adjust the shaft, check condition of the pump parts.  You don't want to ruin a cam lobe because of low oil flow.

Sorry, if you're not a wrench now, you soon will be.  Checking the cam timing, wiggling the rocker arms, cleaning the spray bar, and dropping the oil pump and resetting the distributor shaft aren't that hard.  You have the right pictures of the tang.  Notice how it's not 180 off?  More like 115 or 120.  Somebody goofed up when they reinstalled the oil pump.

 

[Captain Obvious]

I used needle nosed vice-grips stabilized with masking tape:

The rubber bands must have been someone else. 

[siteunseen]

13 hours ago, Captain Obvious said:

The rubber bands must have been someone else. 

RossiZ

I put new oil pump bolts in a month or so ago.  You'll need a new gasket.

When I jack mine up and leave the wheels hanging it's a lot harder dropping that front sway bar enough to get thos e two front bolts out of the oil pump.  I've done it before and it was much easier, I must have had the car up using ramps with the weight on the front end.  That's all I can figure, maybe someone will chime in and clarify that for you?  When you go to bolt that sway bar back up you're gonna need a small bottle jack to push the bar up against the frame and get the bolts started.

Something I thought about too.  If he gets all the TDC marks like the FSM and Blue's site shows do you all think the rotor button may be at #1?  I hate for him to do all that for naught.

There's so many ways to get TDC it's funny but I'll add my way to make it even funnier.  I used stacked feeler gauges to get the bottom of rockers #1 and #2 to be the exact distance from the top of the head.  Wanted to make one out a spark plug but I never knew how hard it is to cut a spark plug. 

Same distance where the circles are...

 

[siteunseen]

 

[Zed Head]

Lots of rounded bolt head edges on that head, and the cam lobes look painfully dry and crudded up.  The valve seals and stems can't be better.  wouldn't be a surprise if a valve was sticking a little, delayed closing maybe.  Or a cam lobe is on its way out.

A picture of the whole head would be interesting and some close ups of the other cam lobes.

[siteunseen]

54 minutes ago, siteunseen said:

Something I thought about too.  If he gets all the TDC marks like the FSM and Blue's site shows do you all think the rotor button may be at #1?  I hate for him to do all that for naught.

Here's a thought from Beer Man Pete on the pulley notch and the timing pointer.

 

[Zed Head]

I built a piston stop from an old spark plug.  Checked my mark once, for fun, the engine already ran fine.  It was on.  

Considering all, and how close it seems to be, I'd spent some extra time with the valve cover off, setting lash, confirming cam timing, confirming TDC, cleaning up the spray bar, etc.  It would be a shame to get it running then blow it up.  It seems like the PO might have just thrown parts together, or tried to fix a few things, and didn't do the greatest job.

[Zed Head]

On 3/16/2018 at 1:29 PM, Av8ferg said:

ZH, I’ll check all that and see what I find.  The sound almost leads me to think a intake valve might not be on the closing and on the compression stroke th I’m getting blow back.  Is this possible?  I guess the fact that my compression checks were good other that #4 @ 145 Psi.  If a valve were stuck i guess it would be close to zero. 

Plus this.  A valve might be bent or hanging in the guide, closing slowly.  Or lash might be too tight, leaving it partly open.  There's a time factor involved when you measure cylinder pressure, the speed of the piston generates the pressure.  If it moved real slow all of the pressure leaks past the rings.  And the pressure gauges have a valve on them to hold the highest pressure, so you can't tell how well the cylinder is really sealing.  A good battery and a fast starter probably gives a higher number than a slow starter.

[Av8ferg]

Thanks for all the advice.  I got called out for work but willl hit the ground running on all these recommendations when I get back a report my findings.  

1. I’ll get more photos of my dirty head.

2. Clean the oil spray bars.

3. Pull the oil pump and reset the spindle position.

4. Check slack on timing chain using a wrench and see it it effects timing markings when tight on drivers side. 

I guess I need to buy some jack stands to do the oil pump.  

My oil pan area is nasty and caked oil crud everywhere under the engine.  They company that rebuilt my alternator said the oil probably killed it.  I don’t want to keep investing in this engine only to discover it’s trashed.  Is it hard to pull the pan and replace the gasket on jack stands.  I’m sure it’s easy on an engine stand.  

Im starting to think finding a rebuilt engine might be a good idea.  

Gas tank is done and will install that too.  

Of note my fuel sending unit looked like crap when I pulled the gas tank.  Totally covered with rust, but still moved.  Companies online wanted around $200 to rebuild it, so I did it myself.  Check out the before and after photos.  I checked the resistance and it went from around 17 to 85 ohms from empty to full.  I let it sit is a bath of muriatic acid mixed 5 to 1 with water for about 30 mins.  Then hit it with WD-40 and plastic brush. Looks great now. 

[Dave WM]

make very sure the muriatic acid is fully neutralized, it will corrode horribly if not. I have used muriatic acid to remove rust before on steel, the  problem is it seems to get into the very pores of the metal, and stays trapped there, causing the corrosion. Keep an eye on that sending unit. See if it looks ok after a day or two. I would have recommended using a less aggressive approach (after what happened to me) but since you have already done it, maybe soaking in a baking soda bath overnight may be something to consider.

I just re read your post, I don't recall the mix I used that had the problem, perhaps your 20% solution will not have the same effects I battled.

Edited March 27, 2018 by Dave WM

[rcb280z]

I would still neutralize it with baking soda to be sure. Wont hurt.