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Old 11-16-2004, 12:14 PM
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Sean79 5spd
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Default Failed Lifters

I will be taking the engine out to seal many leaks, replace motor mounts, etc. I will also want to replace one or more lifters that fairly often make a fair bit of noise.

The question is : how do I tell which lifters are bad. At the fairly high replacement cost I do not want to replace all of them nor do I want to miss replacing the bad ones.

Thanks
Sean
Old 11-16-2004, 12:36 PM
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Chris
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When I had the 87 apart I found I was able to depress a few of the lifters by hand, I left them soaking in oil for a few days but the same. I replaced these and the replacements were firm.

This is just my v limited experience.

Chris
Old 11-16-2004, 12:51 PM
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GlenL
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Use a piece of hose or other mechanics stethoscope to home in on the bad lifters. Then replace the ones that are noisy. May not be able to home in on individual pieces and need to replace a few extras. Don't mix up the parts. I'd get new sleves for the lifters that were replaced.
Old 11-16-2004, 01:09 PM
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BC
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Sleeves? Where are the sleeves?
Old 11-16-2004, 01:11 PM
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Sean79 5spd
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The sleeves are a bit like a valve guide. I believe they are pressed into the cam tower.
Old 11-16-2004, 01:12 PM
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I see no sleeves on the cam towers I have within reach?
Old 11-16-2004, 01:12 PM
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Chris
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No sleeves on my 87

Chris
Old 11-16-2004, 01:15 PM
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Sean79 5spd
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Don't think they are used on the four valve system. They are referred to as a bushing in PET or a sleeve in the WSM.
Old 11-16-2004, 02:14 PM
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Garth S
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Sean,
I have a double fistfull of lifters from a '79: The guy that owned it snapped the nose off the LH cam in '79 or '80 - and having more coin than prudent judgment, had the entire eng rebuilt at < 3000 miles; therefore, I suspect most/all are still OK.
I rescued them for the parts bin, never checked PET5 for an '80 fit - but as you may be in need, drop me a PM when the diagnosis is made ....
Old 11-16-2004, 02:33 PM
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PorKen
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Sleeves were 78-79, only. Later cam towers are all aluminum.

Also of note:
~All the 16V camshafts will supposedly fit in either style tower.

~Early towers have a taller cam bore cap, with a flat for a pressure tap.

~Early towers have rubber bolt hole plugs, later have threaded aluminum.

~Early cams use Woodruff (halfmoon) keys to locate the cam and distributor gears, 80-up use parallel (flat) keys.
Old 11-16-2004, 03:06 PM
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Does you cam advance thing work on the early early cams?
Old 11-16-2004, 04:29 PM
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PorKen
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Originally Posted by BrendanC
Does you cam advance thing work on the early early cams?
Whew! You had me worried for a sec. I have some '79 cams to put in my '81 engine, and I hadn't checked the length of the Woodruff key.

Modified 32V timing gear hub on '79 cam:

click pic for thread


It fits, with about the same amount of key used as on the later parallel key.

Years W x H x L* Type
78-79 4 x 6.5 x 16 Woodruff
80-84 4 x 4 x 16 Parallel
85-95 4 x 4 x 22 Parallel
*(actual sizes are slightly smaller)

Last edited by PorKen; 11-16-2004 at 11:53 PM.
Old 11-16-2004, 05:46 PM
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GlenL
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Originally Posted by PorKen
Sleeves were 78-79, only. Later cam towers are all aluminum.
That's what the PET says. My '80 Euro does have them. A Sept '79 build date but an 80MY nonetheless. Just Porsche getting the inventory turned.
Old 11-16-2004, 10:26 PM
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Earl Gillstrom
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Sean,
Back to your original question, I found the bad lifters on my '88 to be soft when you try to depress them like Chris described. The good ones were hard like you would expect as oil is not compressable. This car had a belt failure with "no damage" that may have caused the lifters to fail without bending valves.
Old 11-16-2004, 11:49 PM
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hupp
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Sean,

The sleeves are not pressed in. They can be easily removed once the cam tower is off and the lifters are removed. Just pull out with two fingers. Once the sleeves are removed you can inspect the gaskets sandwiched between the sleeve flange and cam tower--replace these during your project. I found that some on my engine were torn. Each sleeve has two oil ports and each lifter has a small oil groove around the circumferance. Its concievable that some sludge/varnish has plugged these oil paths and this may be why some lifters are tapping.

The sleeve to lifter fit should have almost no play. I found it impressive how close the tolerances were. Do not mismatch the sleeves and lifters when removing. Keep each pair together install at the location from which they were removed. If you have to replace some lifters buy new sleeves for these lifters as well.

Helpful tip: If you remove the front cam bearings to replace the o-rings, etc., don't forget reinstall before mounting the cam tower on the head. The cam will otherwise be loaded by the valve springs and the bearing will be tough to get back in. I learned this the hard way.


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