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Discussion Starter #1
Got an zetec that the head is shaved .040 put it together and checked compression and it shows 145 across the cylinders. I did do a check on it before head was shaved thought my gauge read 170. Checked it with another focus that has no been shaved and my gauge reads 115 to 120.
 

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Old Phart
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Either two engines aren't working well, or the gauge is off.

Did you happen to change the shraeder valve in the gauge between the earlier test and these? Wrong type, like an old car tire one, will give low readings.
 

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C2H5OH
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I would say the gauge is damaged. Buy or borrow another to verify.

Also, if the engine has not been run and it's a MLS gasket, odds are it's leaking a bit. They require a good heat cycle to seal up well.
 

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Discussion Starter #5
Will try a different gauge tomorrow. Does anyone know where to set cam timming? Checked it a couple different times. Used the tools and set it then started playing with it went one tooth on the crank counterclockwise and gained 10 psi on compression.
 

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Old Phart
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How did you set it to begin with? Only one way for spot on stock.

Confirm 1/4 pistons at TDC and the cam bar straight in the slots for perfect.
 

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Discussion Starter #7
Used the crankshaft peg to lock in tdc and used the flat bar. Routed belt from crank and work couner clockwise while routing belt do there was no slack on the idler side.
 

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Old Phart
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Actual full process includes loosening the cam gears to relock them in position AFTER the cam belt is installed & tensioned.

Feeler rod in the #1 plug hole to see TDC helps to confirm the right crank position, lock peg can be in wrong to throw things off.

After it's done, need to rotate it a couple times and bring back to TDC #1 to recheck cams are aligned right.
 

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Discussion Starter #9
I've never listened the can gear because I thought they were keyed with the peg so loosening them I didn't think they would move or get any adjustment. I also usually never use the crankshaft peg use a fail indicator to find tdc or if I'm in a hurry just put the key way at 12. Just didn't know if anyone has ever played with engine timing. My thinking on it is if you take away from the head isn't it going to change timing?
 

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C2H5OH
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6* IIRC

Divide the number of teeth by 360.
 

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C2H5OH
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I've never listened the can gear because I thought they were keyed with the peg so loosening them I didn't think they would move or get any adjustment. I also usually never use the crankshaft peg use a fail indicator to find tdc or if I'm in a hurry just put the key way at 12. Just didn't know if anyone has ever played with engine timing. My thinking on it is if you take away from the head isn't it going to change timing?

Shaving the head doesn't play into timing at all.



Easiest way to set TDC is by setting BDC.

Valves closed, apply air pressure to 2/3. That will force the piston to true BDC and 1/4 to true TDC. No pins of fancy measuring tools needed.
 

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Yes changes timing (cams retard)...............you have to loosen sprockets and make changes for it. The tensioner must have enough swing to tighten the belt back up too.

You can't just go willy-nilly jumping a tooth to get what you want, you'll blow engine doing that.

Stock 9/1 compression with good seal should be around 170 psi compression or so. Gauges for measuring it are notoriously unreliable and why you take multiple readings and don't even think about doing it until you have a quality gauge in hand.
 

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Discussion Starter #15
Little late on this but thought i would say My gauge was messed up thanks for the help that was bugging me
 
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