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Old 06-24-2008, 08:20 PM
MB, love..hate..love..
 
Join Date: Apr 2003
Location: NB Canada
Posts: 1,173
Ticking lifter Herr Fuchs goes digital

I did my timing chain last winter, and guides, and oil rail fittings. The oil rail (over the camshaft) plastic fittings broke into a hundred tiny pieces when I tried to pry them out, on the passenger side. It took me hours to pick them out and vacuum, wash with solvent, a magnifying glass to hope nothing got missed
.
OK, so the car is finally ready for the road, summers here, so off we go on a nice short 200 mile trip to my buddies place. Everything runs great, until the week before last, when the dreaded 'tick tick tick' starts, for this car, for the first time since I had it (Oct 2007). My thoughts were, naturally, omigod, a piece of oil fitting got into the cam bearing and the cam lobe is toast.....but no, that would do more than one, and I'm sure it's only one lifter, on the passenger side....maybe a stray piece in the lifter?

Only one way to know for sure, so I ordered 2 rockers, 2 lifters (ball studs/HLC's) and 1 oil rail fitting set. My stethescope told me that the problem was in either cylinder 3 or 4, very hard to tell. Parts arrive, so off with the valve cover and I try to understand the Herr Fuchs finger test, gleaned from a thread here (thanks ctaylor738 down this thread a bit http://www.peachparts.com/shopforum/showthread.php?t=119298&highlight=herr+fuchs).

I'm terrible at touchy-feely mechanics, so I tried a variation of this test, which I gather is to see if there is a significant difference in the height of the lifter ball when the cam is point down and heel up, indicating that there is little hydraulic pressure compensating for the slack when the cam lobe is up.

I used a digital caliper, measuring between the bottom of the rocker and the flat on the rim of the lifter, at the center point of the rocker. I had tried the hammer handle test, with no appreciable results, too. My readings produced differences across the 4 lifters I was concentrating on of .44 - .65 mm. As far as I could see, there were no lifters that really changed much in height between cam lobe up and down.

Hmmmm....so all I could try now was change the lifters and/or rockers, starting on cylinder 4, button it up and see what changed. With new lifters in cylinder 4, and the rocker arms re-installed as they were not worn at all, after about 5 minutes idling, again with the 'tick tick tick'. OK, open it up again, reinstall the original lifters in #4, and lets see if it's #3. So I change the first one, and move on to the second....expecting the resistance of a properly torqued down lifter (60 nm), I push on the socket handle and...nothing, no resistance...THE LIFTER WASN'T SCREWED IN TIGHT, ALLOWING THE OIL TO ESCAPE INSTEAD OF PUMPING IT UP!

I bought $100.00 worth of parts I didn't need, thankfully didn't waste time and money on 'flushing additives', and worked 5 hours in 85 degree heat swapping and testing lifters (well, I also put in 8 new plugs while I was all dirty and sweaty). Worth it? You bet it was, I HATE A TICKING LIFTER.

I researched this subject here to death, and no one mentioned this possibility, so FWIW, it might save someone else a bit of time and money.

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Old 06-24-2008, 09:09 PM
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Join Date: Oct 2004
Posts: 4,177
Argh, loose lifter, bloddy hell. I had one where the threaded section of the lifter cracked away from the lifter body. Only found that by running the engine with the valve cover off. Once I saw the oil pouring out from under the lifter did I get a good daignosis.

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