Tapping on cold startups

[Jake59]

First the back story, about 2 1/2 years ago I pulled my 87 Westy 2.1 WBX with 220K on it (I had a oil water milkshake) and had it rebuilt by Jerry at NWCR. The build was up to a 2.2 and I paid the additional fee to have the crank, connecting rods and pistons balanced (seemed like a small cost for the added insurance) I was very happy with Jerry's work and support. Along with the rebuild I replaced OEM exhaust with 10 Cent’s tuned S/S exhaust from RMW. I put the whole thing back together and proceeded with the prescribed “break-in” 500 miles with varying RPM then changed oil etc. Since the motor rebuild I have placed over 20k on her and the power (cruses easy at 70 mph) and performance (18-20 mpg) are just as I would expect. No this was not a swap with 2X HP, but the same WBX I have come to know (very well) and love (low rpm torque).
Now here is my issue, every time the van sits for even a few days I get knocking/tapping until she is fully warmed up i.e. water temp gauge running at 9 o’clock. The tap is on very fire (not from one head or the other) at first quite loud and then slowly fades away. I have tried higher octane but she still taps on cold startups maybe not as loud (?) but still annoying after such an investment. It is as if the hydraulic lifters bleed just a little very time she sits a day or two. I even drove back down to NWCR but by the time I got there she was quiet like a mouse.

So is it the lifters or the octane or something else like the exhust up grade? And my biggest question, with this tapping am I risking the engine’s longevity?
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Curent ride: 87 2WD Westy, 2012 Jetta Sportwagon 2.5S

Past Rides: 62 (23 window) Bus, 64 Ghai convertable, 68 single cab, 72 Super Bettle, 78 Bay window Bus, 84 GTI.

[86scotty]

I had a BMW that did this the whole 5 or so years I owned it. Same symptom. The advice I got from a few mechanics and friends was that one of the oil passages in the valve train was plugged up so it was metal to metal until it heated up enough to circulate the oil and quieten down. The advice was also not to take it apart, as it would certainly get louder/longer if it was getting worse. It never got worse. I'll bet that car still does it every time it's cold.

I havent had a 2.1 apart but I would suspect if you can't live with the noise it will be an expensive problem to fix.
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86 Vanagon Westfalia 87k
1998 Ford E350 4x4 camper build
Vans flip flops

[pablum]

Them's yer tappets, sir.
They will drain if they are allowed to sit for awhile.
And tap until they refill with oil.

Somewhere on theSamba is/are discussion about changing the weight of the oil to reduce this.
Can't remember if it was to raise or lower the weight.
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The wise man learns from history, the fool from experience.
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I see [a cat] in the street and i aim for the pest with my car. -- bluebus86

[0to60in6min]

what grade of oil are you using?
did you replace all the lifters at rebuild?
(http://www.van-cafe.com/home/van/page_1683_706/lifter-new.html)

[Terry Kay]

Toss a guart of MMO in it, go drive it likr you just stole it.

It'll all iron out.
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T.K.

[Jake59]

I have always used 20-50 weight oil with a MANN filter. Jerry recommended Valvoline VR1 because it still had a zinc component for extra lubrication, not always good for your CAT, but helps with high revs and tight engine builds. I have moved to Castrol 20-50 (my preferred brand) and add a zinc oil supplement .

Maybe this is oil/additive mix that is the source of my tapping issue. I may try to go back to the VR1 and see if things quiet down.

I know about the hydraulic lifters that if engine is not run regularly they can/will bleed and then tap until recharged, I just never had it happen in such a short interval. I expect it for not running the van for a month or 2, but never from one weekend to another.

So how long should lifter stay full? Should they not be better on a fresh rebuild? (Yes lifters were replaced)
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Curent ride: 87 2WD Westy, 2012 Jetta Sportwagon 2.5S

Past Rides: 62 (23 window) Bus, 64 Ghai convertable, 68 single cab, 72 Super Bettle, 78 Bay window Bus, 84 GTI.

[0to60in6min]

oil bleeds faster from worn lifters than new ones... my mechanic put new ones without asking me when he rebuild the heads..

I's say about 2 to 3 weeks

[pablum]

If you have a really tight rebuild (and you know this because you have an oil pressure sender/gauge) you can back off on the oil weight. Your lifters could rattle longer if the oil has a hard time getting through.
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The wise man learns from history, the fool from experience.
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I see [a cat] in the street and i aim for the pest with my car. -- bluebus86

[davlance01]

The 20_50 vr1 is how I got rid of the cold start tapping. I'm moving to Mobil 1 synthetic 20/50 and Mobil 1 filter on the next oil change.

I'll let you know if the tapping comes back.
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Life is short and the road is long so if you want to see it all you have to drive fast!