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curt
06-16-2005, 09:31 PM
I'm adjusting valves cold. May the adjustment be done on compression stroke in the exhaust cycle, or must the adjustment be done on the compression stroke in the compression cycle? Why would it make a difference? [?]:)[8D][:0][:I][?]

1949commander
06-17-2005, 08:44 AM
The manual says it must be done on TDC for each cylinders compression stroke. So start at # 1 and follow the sequence. Thiws way you are sure of having each valve lifter setting on the opposite side of the lobe any angle either before or after the opposite of the lobe starts to take the clearance out of the valve train. If you are doing a V-8 or Skybolt6 you need to recheck the clearance HOT as described in the manual. Side valve 6's only have Cold spec. If you don't have a serice manual get one there are worth every dollar.

Hope this helps.

:D

Restore it, don't replace it.Keep the Studebaker reproduction industry going

MarkC
06-17-2005, 02:01 PM
As 1949commander says, the manual specifies TDC on the compression stroke (point of ignition). The manual also has a method when adjusting the valves cold, of using a light connected to the distributor to located TDC. This was more complex than I cared for and relies on ignition timing (which is normally a few degrees advanced from crank timing). My car is a base 259 V8, which fires at 90 degree intervals, so this is what I did. (Standard Disclaimer #83854: This isn't necessarily a recommendation, just an example. I know there are many here with WAY more experience than me that have other methods. So, consider all the possibilities and do what works for you.)

First, I removed the spark plugs and rotated the crank (in the correct direction), lining up the TDC mark on the balancer with the timing pointer, which identifies TDC on cylinder #1. Then, I carefully wrapped a length of masking tape around the circumference of the balancer. (I removed the fan, pulley and belt to gain access. My car doesn't have AC or PS.) I then cut the tape where it overlapped, removed it and laid it out flat to measure it. It was exactly 25 inches, translating to the circumference of the balancer. I then laid out another length of tape, marked the beginning and ending points (at 0 and 25 inches) and made marks at 6.25 inch intervals, dividing the tape into four equal segments. Next, I wrapped the new tape around the balancer, making sure the beginning and ending marks met exactly at the factory TDC mark. Now, the balancer was marked at 90 degree intervals. (This sounds makeshift, but can be done quite accurately if your're careful. I made permanent marks on the balancer so I wouldn't have to do this again.) Starting out adjusting the valves, I adjusted those on cylinder #1, then rotated the crank to the next mark and did the next cylinder in the firing order (#8). From there, it was simple matter to continue rotating the crank to the next mark and adjusting the cylinders in firing order sequence, going through two rotations of the crank.

Of course it would be different for the 6's, but you could do something similar.

Take care.

Mark

MarkC, 64 Y8
Working in Spokane, WA

curt
06-17-2005, 05:44 PM
quote:Originally posted by MarkC

As 1949commander says, the manual specifies TDC on the compression stroke (point of ignition). The manual also has a method when adjusting the valves cold, of using a light connected to the distributor to located TDC. This was more complex than I cared for and relies on ignition timing (which is normally a few degrees advanced from crank timing). My car is a base 259 V8, which fires at 90 degree intervals, so this is what I did. (Standard Disclaimer #83854: This isn't necessarily a recommendation, just an example. I know there are many here with WAY more experience than me that have other methods. So, consider all the possibilities and do what works for you.)
Thank you for the reply.I have a 1955 Shop Manual, It does not say the valves are to be set hot. This is a hot topic, it says with the engine's # 1 cylinder in the compression strok and the UDC 1-6 Mark on the damper directly under the timing pointer set the #1 valve clearance.... Now UDC 1-6 is a new term to me . Is that TDC 1-6 degrees advanced,1-6 degrees retarted? What is UDC?? The tape is unique and sounds like a sound procrdure.
First, I removed the spark plugs and rotated the crank (in the correct direction), lining up the TDC mark on the balancer with the timing pointer, which identifies TDC on cylinder #1. Then, I carefully wrapped a length of masking tape around the circumference of the balancer. (I removed the fan, pulley and belt to gain access. My car doesn't have AC or PS.) I then cut the tape where it overlapped, removed it and laid it out flat to measure it. It was exactly 25 inches, translating to the circumference of the balancer. I then laid out another length of tape, marked the beginning and ending points (at 0 and 25 inches) and made marks at 6.25 inch intervals, dividing the tape into four equal segments. Next, I wrapped the new tape around the balancer, making sure the beginning and ending marks met exactly at the factory TDC mark. Now, the balancer was marked at 90 degree intervals. (This sounds makeshift, but can be done quite accurately if your're careful. I made permanent marks on the balancer so I wouldn't have to do this again.) Starting out adjusting the valves, I adjusted those on cylinder #1, then rotated the crank to the next mark and did the next cylinder in the firing order (#8). From there, it was simple matter to continue rotating the crank to the next mark and adjusting the cylinders in firing order sequence, going through two rotations of the crank.

Of course it would be different for the 6's, but you could do something similar.

Take care.

Mark

MarkC, 64 Y8
Working in Spokane, WA

curt
06-17-2005, 05:48 PM
My last reply is messed up. TRY AGAIN: What is UDC 1-6 mean? This is relateded to top dead center and the vibration damper markings. The term is in the 1955 Shop Manual, Engine Section page 49.

MarkC
06-20-2005, 10:21 AM
The UDC mark is actual top-dead-center. The IGN mark is 4 degrees BTDC (at least in the the 59 and up service manual).

MarkC, 64 Y8
Working in Spokane, WA