How to check that a crank and cam shaft are good to use? |
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How to check that a crank and cam shaft are good to use? |
Tdskip |
Jun 15 2020, 03:48 PM
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#1
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Advanced Member Group: Members Posts: 3,686 Joined: 1-December 17 From: soCal Member No.: 21,666 Region Association: None |
Hello gentlemen-hope everybody had a good weekend and is staying safe.
Like many of you I’m trying to use the extra time at home to sort through parts, and I’ve got two 2.0L cranks and camshafts that have been wrapped up in newspaper in stored for anywhere from 10 to 20 years. Beyond looking for nicks or signs of heat and any corrosion, could you guys educate me on what I should be looking at to determine if these things are any good? Imagine getting a micrometer on the crank to determine size it would be a good step? Thanks |
porschetub |
Jun 15 2020, 04:45 PM
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#2
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Advanced Member Group: Members Posts: 4,704 Joined: 25-July 15 From: New Zealand Member No.: 18,995 Region Association: None |
Hello gentlemen-hope everybody had a good weekend and is staying safe. Like many of you I’m trying to use the extra time at home to sort through parts, and I’ve got two 2.0L cranks and camshafts that have been wrapped up in newspaper in stored for anywhere from 10 to 20 years. Beyond looking for nicks or signs of heat and any corrosion, could you guys educate me on what I should be looking at to determine if these things are any good? Imagine getting a micrometer on the crank to determine size it would be a good step? Thanks Tom send the cranks out for checking and if the pass muster get them polished. Stock cams are known for wear on the lobes so if they aren't replacements there will be wear,this is also caused when the lifters go flat or even worse go slightly hollow on the running faces. Post pics of the cams,cheers. |
Mueller |
Jun 15 2020, 04:47 PM
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#3
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914 Freak! Group: Members Posts: 17,146 Joined: 4-January 03 From: Antioch, CA Member No.: 87 Region Association: None |
Hello gentlemen-hope everybody had a good weekend and is staying safe. Like many of you I’m trying to use the extra time at home to sort through parts, and I’ve got two 2.0L cranks and camshafts that have been wrapped up in newspaper in stored for anywhere from 10 to 20 years. Beyond looking for nicks or signs of heat and any corrosion, could you guys educate me on what I should be looking at to determine if these things are any good? Imagine getting a micrometer on the crank to determine size it would be a good step? Thanks The Haynes manual gives you numbers that you could check with a mic. You could also check some measurements or straightness with some v-blocks and an indicator. Or send to a shop that deals with these motors and have them inspect it. You can also hang the crank by a rope and hit it and listen for a nice ring. If a dual thud there is a crack someplace usually. (sure there are some youtube videos explaining it better) |
Tdskip |
Jun 15 2020, 05:01 PM
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#4
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Advanced Member Group: Members Posts: 3,686 Joined: 1-December 17 From: soCal Member No.: 21,666 Region Association: None |
Thanks for the responses.
If the cams look new / no wear then that suggests they haven’t been run I suppose? Will get some pictures posted. Thanks! |
Mark Henry |
Jun 15 2020, 07:10 PM
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#5
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
Check the lifters, not the cam. Lifter faces are slightly convex, if they're flat or concave I'd replace the cam and lifters. Easy to see if you hold two lifters face to face up to a light.
Back in the day you could stick new lifters on an ok used cam, but I wouldn't try that now. In the mid 2000's the T4 had huge lifter/cam supply and quality issues. Long story short it's why you now have to go with known combo's of cams and lifters. |
Tdskip |
Jun 15 2020, 07:12 PM
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#6
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Advanced Member Group: Members Posts: 3,686 Joined: 1-December 17 From: soCal Member No.: 21,666 Region Association: None |
Check the lifters, not the cam. Lifter faces are slightly convex, if they're flat or concave I'd replace the cam and lifters. Easy to see if you hold two lifters face to face up to a light. Back in the day you could stick new lifters on an ok used cam, but I wouldn't try that now. In the mid 2000's the T4 had huge lifter/cam supply and quality issues. Hi Mark - I don't have lifter in the parts bin, just the cranks and cams.' Great tip however, will look at those when I take apart the Type 4 with a smoking problem. |
Valy |
Jun 16 2020, 09:05 PM
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#7
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Senior Member Group: Members Posts: 1,677 Joined: 6-April 10 From: Sunnyvale, CA Member No.: 11,573 Region Association: Northern California |
Measure the crank. If not in spec, it can be grounded down a bit for reuse.
For the camshaft, look at the lobes. If you see any depressions on the lobes, it is a good paperweight. |
Mark Henry |
Jun 17 2020, 11:33 AM
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#8
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
Hillbilly magnaflux. (IMG:style_emoticons/default/shades.gif)
Hold the crank in your hand by the nose and rap one of the webs with a ball peen hammer, if it rings like a bell it's likely good. If it just thuds then it's likely cracked. This doesn't replace magnaflux inspection, but I've never had a ringing crank fail magnaflux. |
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