Valve spring shifting around in head, Has anyone else seen this happen? New pics added |
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Valve spring shifting around in head, Has anyone else seen this happen? New pics added |
reharvey |
Jun 20 2012, 08:42 AM
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#1
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Senior Member Group: Members Posts: 573 Joined: 16-July 08 From: N. E. Ohio Member No.: 9,308 Region Association: North East States |
Was looking for a rebuildable 2.0 head in my pile of stuff and I came across this one with an issue I've never seen before. It looks like the base on the valve spring has been moving back a forth in the head. If you look at the first pic you can see the metal has been pushed up to make a ridge at one side. The second pick shows that the valve guide boss as been repaired and is smaller then normal. So--has anyone seen this happen before? What needs done to repair the damage to the head? Thanks, Ray
Attached thumbnail(s) |
ldsgeek |
Jun 20 2012, 08:52 AM
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#2
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Member Group: Members Posts: 155 Joined: 27-June 10 From: New Hampshire Member No.: 11,885 Region Association: None |
I'm not sure, but shouldn't there be a steel washer under the spring? When I worked at an auto machine shop (too many years ago) every aluminum head I touched had steel between the spring and the head to protect the softer head.
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reharvey |
Jun 20 2012, 10:10 AM
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#3
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Senior Member Group: Members Posts: 573 Joined: 16-July 08 From: N. E. Ohio Member No.: 9,308 Region Association: North East States |
These heads never came with washers under the valve spring
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ldsgeek |
Jun 20 2012, 10:41 AM
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#4
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Member Group: Members Posts: 155 Joined: 27-June 10 From: New Hampshire Member No.: 11,885 Region Association: None |
Ok, I was wrong about these. Sorry. It does make sense but I guess VW/Porsche tested and found they weren't needed.
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wingnut86 |
Jun 20 2012, 01:35 PM
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#5
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...boola la boo boola boo... Group: Members Posts: 1,053 Joined: 22-April 10 From: South Carolina Member No.: 11,645 Region Association: South East States |
Send it off to Len at Hoffman Machine or find a "Type 4" head specialist close by.
Valve guides that start to wear can cause this, add in the possibility of valve seats that have come loose or are wearing unevenly and you have this. Experts can weigh in but this has been my experience in aluminum heads so far. A rebuilder can build up that surface and machine to spec if not to "wallered out" Jake, Cap'n, McMark, Chris or Len?? |
Katmanken |
Jun 20 2012, 01:46 PM
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#6
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You haven't seen me if anybody asks... Group: Members Posts: 4,738 Joined: 14-June 03 From: USA Member No.: 819 Region Association: Upper MidWest |
I'm almost thinkin the spring and valve are at a different angle than stock. One way to get that effect is to weld up the exhaust guide boss and mis-drill the hole for the guide at an angle. Then when you put the spring on, it's off center and tipped. Measure with calipers and compare to your other head.
What does the combustion chamber look like? Specifically look at the valve seat to see if it's canted, or if the valve seat cuts are cut at an angle to "accomodate" a mis-angled valve. |
McMark |
Jun 20 2012, 02:16 PM
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#7
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
The seats could have been recut too far and allowed the valve to seat farther in the head. This would make more clearance for the valve spring, and with enough cutting the spring could ride relatively freely and spin.
Pics of the valve head / combustion chamber please. |
reharvey |
Jun 20 2012, 03:02 PM
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#8
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Senior Member Group: Members Posts: 573 Joined: 16-July 08 From: N. E. Ohio Member No.: 9,308 Region Association: North East States |
The valve seat looks original and is in good condition. No other visable damage on the combustion chamber side.
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reharvey |
Jun 21 2012, 08:40 AM
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#9
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Senior Member Group: Members Posts: 573 Joined: 16-July 08 From: N. E. Ohio Member No.: 9,308 Region Association: North East States |
I added two more photos of my valve spring problem. Anyone else have any ideas? Thanks, Ray
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McMark |
Jun 21 2012, 09:36 AM
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#10
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
Perhaps that spring lost tension...
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