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If your head is within spec for warpage (I think its about 0.002-0.003 "), someone confirm- do not have it shaved/resurfaced. You want to keep as much of your head as possible and not resurface for nothing.
 

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Good point, the scotch brite is the finishing step! If the head is flat and has never been touched I like to have a clean sealing surface only milling a couple of thou can give you. Your call for sure.
 

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Discussion Starter #45
So close...

I am putting everything back together and I found a red and black wire with a blade connector that came loose in the vicinity of the starter. I traced it back to the same bundle as the large black and red wires that connect to the starter. Can anyone tell me where it plugs in?
 

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The red/black wire should be the lead for the oil sending unit that is directly above the starter. Best to isolate it, turn the ignition to the 1 position and read voltage to ground - it should be zero. If it is, then ground it and see if the oil gauge moves - it should peg at full. If so, then you are safe to plug it into the oil sending unit.
 

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Red with black stripe is oil pressure sending unit. The wire that appears to be in your hand looks orange. There is an orange wire that goes to the brake line junction/manifold in that area as well. Opps, missed the above post
 

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Discussion Starter #49
Running rough

I finally finished putting everything back together. The mission creep as I found other things to do cost me several days. After filling up the oil and coolant, I started the ignition. It took several attempts, but my Spider finally started up.

My car is running rough. It sounds like something is knocking around under the cam cover. I neglected to push out the chain tensioner in addition to releasing the nut and letting the spring push it out. I'm hoping a loose chain threw off the timing. The engine also smokes after running about 5 minutes, coming from the exhaust side. I don't see smoke from the cam when I take off the oil cap.

Is there anything else I need to look for when I take the cam cover off?
 

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Discussion Starter #51
I took off the cam cover and saw that the chain was very loose. I reset the timing with a tight chain and now the car is running smoothly.

However, there is a distinct clattering noise from within the cam or head that coincides with the engine speed.

I took my car to Autozone since it was 8 PM and the guy said it sounds like a valve is hitting a piston.

The shop that repaired my cylinder head also changed the stem seals, set cam clearances, and cleaned the valves. They did not change any valves, guides, or springs.

Any suggestions on what to check next?
 

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Discussion Starter #52
Compression check

Here is one more bit of diagnostic information. The compression check before and after the work on the cylinder head and replacement of the head gasket is:

#1 150 before, 135 after
#2 175 before, 160 after
#3 160 before, 170 after
#4 120 before, 130 after

Does this indicate the valve clearances weren't adjusted properly? I will measure them next.
 

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Hmm, not sure what to make of that - two cylinders are worse, two better. Are you sure you ran compression the EXACT same way? Did you hold the throttle wide open? Compression testers are not the most precise of instruments. Regardless, the numbers aren't great but still road worthy. Ideally you'd like to see 140 to 160 with no more than a 10% spread. In that respect you are actually better off with the new numbers. If a valve was hitting a piston I think you would be reading zero as the valve would be quickly bent. You can squirt a little oil in each cylinder and repeat the test. If the compression increases it may indicate that you've got worn rings.

You might want to do a leak down test. It's pretty straight forward with these motors - pressurize the cylinder and see if it leaks. Perhaps Autozone can lend you the tool.

Valve clearance (lash) would have nothing to do with the compression or the clattering noise. Not to say that it should be ignored. It can be very serious (like broken motor serious) or very simple (like something hit the fan blade). I don't know that I would trust an Autozone salesperson's judgement. Find an old mechanic and have him give a listen. Until then I would be very cautious about driving it around.

A few more questions:
  • How is the oil pressure & level?
  • Any smoke out of the tailpipe? If so, what color?
  • Are you certain the cams are timed properly (timing marks lined up)?
  • What do the sparkplugs look like?
  • What does the oil look like?
 

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What Rich just said.

To that I will add that you really should stop where you are and go back and check everything. Something is wrong and you don't know what it is. So, the very first step is start over and make sure everything, timing, cam-timing, chain tension, etc., etc., is set to standard. That will give you a baseline that you can be confident with. Otherwise, you can end up chasing your tail while simultaneously overlooking something important. Ask me how I know . . . :001_smile:

The sudden loss of compression accompanied by the internal noise is troublesome. Definitely squirt oil in the cylinders and run your compression check. If the compression comes up = worn rings (unlikely). If it stays the same = damaged or poorly seated valves. Also, once everything is set to standard, run a leakdown test.

You really shouldn't drive the car until you've gotten a handle on what's going in in your motor.

Good luck. Keep us posted.
 

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As advised above, I'd re-do the compression test, first dry and then wet, but make sure you have a hot engine, all plugs out (so starter turns fast), and throttle held wide open.
 

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When I did the head gasket on my car I had the head looked at.

The thinnest of a skim cut on the head and valve seats cleaned up and clearances adjusted.

First start up and a loud clatter.

One of the shims got out of place under the tappet.
 

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Discussion Starter #57
Checking everything...

Thanks for all the suggestions.

Cam timing, TDC, and distributor timing look good. Chain is tight. Tensioner is locked in place. Sparkplugs are brown and dry. Oil looks good. Need to check oil pressure on next startup. Small amount of white smoke came out of exhaust when I first started up, but has since gone away.

I found that the intake camshaft covers 4 and 5 were in the wrong order and were turned 180 degrees around. I corrected them and torqued the nuts to 15 ft/lbs. I then checked the valve clearances and got:

Intake spec 0.40-0.45:
#1 0.31
#2 0.45
#3 0.66
#4 0.44

Exhaust spec 0.45-0.50:
#1 0.46
#2 0.40
#3 0.49
#4 0.54

Could the valve clearance be causing the noise? Should I remove the tappets and check for something loose?

I will do another compression test, dry and wet, after I put the cam cover back on.
 

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Intake spec 0.40-0.45:

Exhaust spec 0.45-0.50:
Just to be absolutely clear here: you are talking about millimeters right? The specs should be 0.017 inches for intake and 0.019 inches for exhaust which would be 0.43 and 0.48 mm respectively.
 

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Some of those wider ones could for sure cause a noise.
 
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