Dan Sarandrea (Phila)
Waitin' On Parts...
[Continued from Valve Adjustment, Part One http://xwebforums.com/forum/index.php?threads/25490/ ]
In Part One we removed the cam top cover, measured our existing clearances, and recorded them. Now we are ready to remove and measure our shims. The new forum software allows 10 pics per post, so I had to break Part Two into Part Two-A and Part Two-B.
In Part 3, we'll, calculate if thinner or thicker shims are needed, select the needed shim, and install.
OK, here we go with Part Two-A.
When adjusting valve clearances, you have to know two measurements:
1. What is the existing clearance?
2. What thickness is the currently installed shim?
The only way to find out #2 is to remove the existing shim and either (a) measure it or (b) look for the marking printed on it.This is probably the second-most time consuming and "fiddly" task on our cars, because removing the valve adjustment discs (aka shims) can be a royal pain in the ass.
OK here goes.
You'll need an assortment of pick tools, small screwdrivers, a magnetic stick, shop rags, a little clean engine oil, and of course a drop light to see what you are doing. You will also need the FIAT special tool to depress the shim buckets. I have seen many nicknames here on XWeb for the tool; some call it a valve adjusting tool, a shim tool, bucket tool, bucket depression tool, etc. I can recommend XWeb Member Brian Pimm's custom designed SOHC shim tool. Contact Brian here: http://xwebforums.org/member.php?u=1198 I imagine a very experienced and confident shadetree FIAT guy could do this job with big pry tools, but for the rest of us, the real shim tool is essential and well worth the cost.
Starting at cylinder #1 like you did when measuring the existing clearances, rotate the engine clockwise using the right rear wheel until both cam lobes are positioned so that neither is in contact with its corresponding shim and bucket. You also want the lobe for the valve you are working on to be positioned to afford maximum gap between the cam lobe heel and the shim to give you as much room as possible to extract the shim.
Next, use your finger to dip into the pooled oil in the cambox and coat the business end of the shim tool with oil. Position the tip of the tool between the two cam lobes. Note how the two shoulders of the tool will bear on the two shim buckets and note how the center spine of the tool fits in between the buckets and works against the cam box casting. This is why your positioning of the cam lobes is important...the buckets must be at equal heights and not depressed by the cam lobe, or else the center spine of the tool will not be supported by the other bucket and the tool will slide off the non-depressed bucket and jam under the cam.
Now use the tool like a lever, pressing down on the handle while simultaneously pushing the tool toward the camshaft. The eccentric head on the tool will depress the pair of shim buckets. The shim buckets will rotate toward the tool about 90 degrees as the tool is depressed, so you will want to pre-position the notch so that it ends up at the 3 o'clock position as shown in the pic.
Positioning the cam properly and depressing the shim bucket with the tool is done to increase the gap between the shim bucket and the cam to where there's enough space to pull out the shim.
Now we attempt to remove the shim from the top of the shim bucket. Try a good stick magnet first, if you're lucky the shim will almost jump out of the bucket.
My experience was that the first two shims came out with just the magnet, the rest needed a LOT of prying and coaxing with picks. The best tool turned out to be the long skinny screwdriver with the tip bent at about a 30 degree angle.
Please follow this link to go to Part Two-B:
https://xwebforums.com/forum/index.php?threads/valve-adjustment-part-two-b.34270/
In Part One we removed the cam top cover, measured our existing clearances, and recorded them. Now we are ready to remove and measure our shims. The new forum software allows 10 pics per post, so I had to break Part Two into Part Two-A and Part Two-B.
In Part 3, we'll, calculate if thinner or thicker shims are needed, select the needed shim, and install.
OK, here we go with Part Two-A.
When adjusting valve clearances, you have to know two measurements:
1. What is the existing clearance?
2. What thickness is the currently installed shim?
The only way to find out #2 is to remove the existing shim and either (a) measure it or (b) look for the marking printed on it.This is probably the second-most time consuming and "fiddly" task on our cars, because removing the valve adjustment discs (aka shims) can be a royal pain in the ass.
OK here goes.
You'll need an assortment of pick tools, small screwdrivers, a magnetic stick, shop rags, a little clean engine oil, and of course a drop light to see what you are doing. You will also need the FIAT special tool to depress the shim buckets. I have seen many nicknames here on XWeb for the tool; some call it a valve adjusting tool, a shim tool, bucket tool, bucket depression tool, etc. I can recommend XWeb Member Brian Pimm's custom designed SOHC shim tool. Contact Brian here: http://xwebforums.org/member.php?u=1198 I imagine a very experienced and confident shadetree FIAT guy could do this job with big pry tools, but for the rest of us, the real shim tool is essential and well worth the cost.
Starting at cylinder #1 like you did when measuring the existing clearances, rotate the engine clockwise using the right rear wheel until both cam lobes are positioned so that neither is in contact with its corresponding shim and bucket. You also want the lobe for the valve you are working on to be positioned to afford maximum gap between the cam lobe heel and the shim to give you as much room as possible to extract the shim.
Next, use your finger to dip into the pooled oil in the cambox and coat the business end of the shim tool with oil. Position the tip of the tool between the two cam lobes. Note how the two shoulders of the tool will bear on the two shim buckets and note how the center spine of the tool fits in between the buckets and works against the cam box casting. This is why your positioning of the cam lobes is important...the buckets must be at equal heights and not depressed by the cam lobe, or else the center spine of the tool will not be supported by the other bucket and the tool will slide off the non-depressed bucket and jam under the cam.
Now use the tool like a lever, pressing down on the handle while simultaneously pushing the tool toward the camshaft. The eccentric head on the tool will depress the pair of shim buckets. The shim buckets will rotate toward the tool about 90 degrees as the tool is depressed, so you will want to pre-position the notch so that it ends up at the 3 o'clock position as shown in the pic.
Positioning the cam properly and depressing the shim bucket with the tool is done to increase the gap between the shim bucket and the cam to where there's enough space to pull out the shim.
Now we attempt to remove the shim from the top of the shim bucket. Try a good stick magnet first, if you're lucky the shim will almost jump out of the bucket.
My experience was that the first two shims came out with just the magnet, the rest needed a LOT of prying and coaxing with picks. The best tool turned out to be the long skinny screwdriver with the tip bent at about a 30 degree angle.
Please follow this link to go to Part Two-B:
https://xwebforums.com/forum/index.php?threads/valve-adjustment-part-two-b.34270/
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