Author Topic: Cam Degreeing Procedure  (Read 380 times)

Offline Ronno6

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Cam Degreeing Procedure
« on: December 11, 2018, 08:58:37 AM »
I am getting ready to degree the cam in my 350 build.
I am a cam degreeing virgin.........
I have watched several videos on the procedure and curious as to the
lack of attention regarding crankshaft rotation direction
I would have to believe that ALL measurements would HAVE to be taken
with the crank rotating clockwise in order to assure the timing chain tension
on the right side.
This may not be of concern if there is absolutely ZERO play in the timing chain.
Timing set is a new Cloyes double roller setup.

Am being overly pedantic here?
 
You can lead a man to water, but yoiu can't keep him from pissing in it.

Offline 75gmck25

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Re: Cam Degreeing Procedure
« Reply #1 on: December 11, 2018, 09:07:53 PM »
Once you verify TDC and line up your pointer with the zero point on the degree wheel, then you do all the degree measurements while turning clockwise.

A few challenges I had when degreeing the cam:
- I bought a degree wheel from Jegs that did not have simple 360 degree markings.  However, every video I looked at showed a wheel with just 0-360 tick marks.  I had to just count ticks on the wheel instead of looking a simple numbers from 0-360. 
- The degree wheel did not come with a crankshaft turning tool, and the hole in the wheel was only big enough to bolt the wheel itself on the end of the crankshaft.  There was no way to install a turning tool on the crankshaft snout after the wheel was mounted.  Trying to use the flywheel would not have worked well, since the engine was still in the truck.  Other manufacturers do sell a degree wheel/crankshaft tool combination that would work better. Those wheels have a hole that is big enough to let you slip the wheel on first, and then add the turning tool.
- I had the heads off, and the pin on the dial indicator was either very short or very long (it came with an extension).  This made it harder to keep it aligned and vertical all the time.
- Finding the base circle and exact .050 lift points was challenging, mostly because it was hard to turn the engine over smoothly.  In the videos they usually had a very large turning tool on the back of the engine and it was easy to turn very small amounts.  I had a fairly short wrench around the crankshaft snout trying to also turn small amounts, and I couldn't do more than about 90 degrees without moving the wrench because I was hitting obstructions in the engine compartment or losing my leverage.  It took several tries to get decent measurements. 

Bruce

Offline Ronno6

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Re: Cam Degreeing Procedure
« Reply #2 on: December 11, 2018, 10:36:00 PM »
Fortunately I am working with a block w/crank,#1 piston/rod,cam,timing set and lifter as needed, all mounted on the engine stand.
I should be able to turn with the flex plate and turning the indicator so I can see it from the rear.

I would still have to believe that establishing TDC MUST be done whole turning the crank clockwise in order
to keep any chain slack out of the equation.
You can lead a man to water, but yoiu can't keep him from pissing in it.

Offline VileZambonie

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Re: Cam Degreeing Procedure
« Reply #3 on: December 12, 2018, 04:17:28 AM »
Correct, you turn the crankshaft clockwise. A crank turning nut makes this a lot smoother and accurate.
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