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| | | | Joined: Jan 2010 Posts: 4,263 Shop Shark | | Shop Shark Joined: Jan 2010 Posts: 4,263 | 1954 235 z TDC question
This may sound elementary
If my pointer is on the ball and rotor pointing to number 1 wire
and both my pushrods are loose on # 1
Would that mean that #1 is on the compression stroke.
Or does that happen again in the cycle?
Second
Last time I did a compression check I only removed the spark plug on the cylinder I was testing. Is that correct or should I have them all removed ?
Thanks | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | If my pointer is on the ball and rotor pointing to number 1 wire
and both my pushrods are loose on # 1
Would that mean that #1 is on the compression stroke. Yes - regarding compression stroke (move flywheel/crankshaft until both push rods are loose) | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | Last time I did a compression check I only removed the spark plug on the cylinder I was testing. Is that correct or should I have them all removed ? "Disconnect the main wire to the coil and spark plug wires; remove spark plugs." Remove all spark plugs - 1954 Truck Shop Manual | | | | | Joined: Jan 2014 Posts: 3,677 'Bolter | | 'Bolter Joined: Jan 2014 Posts: 3,677 | I guess "plugs in" would work for compression issues related to rings or valve seating (cylinder specific issues), but might not be so good at accurately diagnosing bad head gasket/ cracked head (compression loss between two cylinders).
Am I thinking of that correctly?
1951 3100
| | | | | Joined: Nov 2006 Posts: 2,544 Shop Shark | | Shop Shark Joined: Nov 2006 Posts: 2,544 | This shows the 4 stroke engine. Intake, compression, combustion and exhaust. This should help you identify where your at when bringing an engine to TDC for installing a distributor. http://en.wikipedia.org/wiki/Four-stroke_engine | | | | | Joined: Sep 2014 Posts: 385 Shop Shark | | Shop Shark Joined: Sep 2014 Posts: 385 | Remember the ball is not actually tdc. It should be 5deg before with all the info I have found over the years. | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | Remember the ball is not actually tdc. It should be 5deg before with all the info I have found over the years. That is correct for most year flywheels, but the timing mark could be before or after TDC depending on year and engine (216/235/261) flywheel. To complicate this, people often changed flywheels for various reasons. | | | | | Joined: Jan 2010 Posts: 4,263 Shop Shark | | Shop Shark Joined: Jan 2010 Posts: 4,263 | Yes
I'm not referring to true TDC
But for starting and timing purposes.
Thanks for the information
| | | | | Joined: Jan 2014 Posts: 3,677 'Bolter | | 'Bolter Joined: Jan 2014 Posts: 3,677 | Remember the ball is not actually tdc. It should be 5deg before with all the info I have found over the years. That is correct for most year flywheels, but the timing mark could be before or after TDC depending on year and engine (216/235/261) flywheel. To complicate this, people often changed flywheels for various reasons. My head just exploded. Can I at least assume that the timing mark is close enough to TDC for initial timing/ startup purposes? Or can the mark be way off and meaningless if the flywheel was replaced?
1951 3100
| | | | | Joined: Sep 2014 Posts: 385 Shop Shark | | Shop Shark Joined: Sep 2014 Posts: 385 | If the wrong or different flywheel is used on another engine setting the timing to the ball can cause a black hole..... everything as we know it will end.
The ball mark will get the engine running fine. Then adjust from there after your running. | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 |
As wolffcub posted, any timing mark/ball will get you close enough to get it started.
After getting the carburetor adjusted to idle speed, I use a vacuum gauge to adjust timing and carburetor mixture to obtain maximum vacuum reading.
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