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Tightmopedman9

The VAST Wagon Build

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Rule of thumb, is normally, loose valves cause noise (as the tappet comes off the cam/rocker arm).

However, I have had personal experience with tight valves causing noise (though, not on a Volvo engine).

With that, I'll give you some maybe-not-so-necessary advice. 

Try to get your hands on a stethoscope.  You will use it now, and forever, when attempting to diagnose a noise.

 

When I'm hunting a noise, one thing that I observe is the pace of the noise.  The faster pace (because camshafts turn faster than crankshafts) points in one direction, and vice versa.

Since you're into the top-end of your engine, I'll assume you've heard what a loose valve sounds like.  Is the noise similar?  Usually, when my ears hear a top-end noise, I would describe it as a clank.  When I hear a bottom-end failure, I would use the word clunk - there's more metal behind the noise.

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I picked up 9 shorter tappets based on the measurements I took, and by shuffling around the tappets I already had I was able to get all but two of the valves within spec. I'm about an hour away from startup now. 

I visually checked all the keepers after install and then used the valve compressor tool to depress each valve. I also hammered on the tip of each valve with a plastic dowel.

I have a stethoscope, the problem is that I didn't want to leave the car running for an extended amount of time when it sounded like that, in case there was something rattling around that might cause more damage. Now that I know there is no foreign material, if the noise comes back I'll be able to trace the sound more thoroughly. 

My first thought when I heard the noise was bottom end. It had the characteritic noise of a spun bearing or some other crank ailment. However, the noise was definitely coming from the top end. 

 

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Now you're onto it! There's nothing like measurement to help know where you stand.

re: bottom end

With the cams out and plugs out, did you rotate by hand to feel for any resistance?
With the pan off it wouldn't hurt to take a look at the rod bearings.

Probably not necessary, and probably too late at this point anyways.

Keep us posted!
 

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...observe is the pace of the noise.  The faster pace (because camshafts turn faster than crankshafts) points in one direction, and vice versa.

Just to be AR, and FYI, the cams turn at half speed of the crank; not 2x (i.e. faster).  But your point about listening for the cadence of the noise is still valid..  :closedeyes:

Edited by gdog
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With the cams out and plugs out, did you rotate by hand to feel for any resistance?
With the pan off it wouldn't hurt to take a look at the rod bearings.

First thing I did was take the pan off and inspect. That's when I took the picture of the keeper on top of the oil pan.

I rotated the crank plenty of times. Never ran into any resistance.

I got her all back together, started her up and the noise was still there. :angry: Kicked some things around the garage, cleaned up a bit and started it again without any noise. After 5 minutes of idling she's silent. I'm gonna clean the engine bay tomorrow and take her for a spin. I'll post some pictures of new additions shortly. 

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Just to be AR, and FYI, the cams turn at half speed of the crank; not 2x (i.e. faster).  But your point about listening for the cadence of the noise is still valid..  :closedeyes:

Yes, you are correct.

 

I don't know how I was mixed up with that...

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I'm curious. Did the noise only occur during combustion or also during cranking w/out fuel or spark? ...probably didn't think to go so far as to test that?

You have an odd problem. I'm stumped.

and you're SURE that it's not VVT hubs? I don't know what they sound like, so forgive me if I'm off base here, but a long time ago on a completely different platform we had an awful clank clank clank noise happen out of nowhere and we were convinced that the bottom end was done. It turned out to be a loose adjustable cam gear that was slapping back and forth with cam/valve operation. ....we didn't catch that until after we decided to part out the car. haha

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I had motivation to drop the pan because I bought Hussein's crank scraper, Focus RS oil cooler and S60R baffled oil pan.

E8kR

0ofU

The inlet coolant port on the Focus RS oil is rotated vs the stock cooler. Hussein elected to bend his stock coolant pipes. I decided to cut and re-weld the inlet.

Stock configuration:

 jpY1

Hussein's setup:

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Re-weld:

Jmnd

 

I also redid the catch can setup, before it vented to atmosphere via two large filters. This allowed for a lot of in cabin smell and made me and my passengers quite nauseous after a short drive. I added a E-vac scavenger from Vibrant into the downpipe.

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I then added a checkvalve in line (NAPA 2-29000) to prevent backfires from pressurizing the crankcase.

yVn3

Since the Vibrant is only a 10AN fitting and I have two 10AN and one 12AN into my breather box I wanted to add an additional outlet. I welded a 3/4NPT pipe nipple to the intake tube and placed another check valve in line. This check valve will prevent negative pressure from the venturi in the exhaust from sucking intake air in, instead of crankcase gases. However, it will open up as soon as there is any positive pressure in the crankcase.

r-BX

With this setup I get -.3psi above 1000RPM until redline at 24psi. Not exactly an insane amount of vacuum, but at least there is no positive pressure, and I don't have to smell crank case gasses.

Some overdue pictures of the torque rod I re-purposed from an EVO and my Mercedes projector retrofits into C70 jewels.

Nr5b

AbtU

VGCw

Edited by Tightmopedman9
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Nice! So, do you think the noise was just a lifter - or are yours solid - I lost track there.

Front end will look better when the big package gets to you :)

 

 

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I think it may have been an oil pressure related issue and the VVT hubs were clacking until an adequate oil pressure had been built up. Although that doesn't really explain the noise going away and then popping back up a few minutes later. I just didn't feel comfortable leaving the car running long enough with the thought that there might be some foreign chunk of metal floating around. 

 

This is the Volvo tool for checking valve lash:

Cam%20Hold%20Down.JPG?dl=0

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interesting tool. I like it.

I have heard of distorted and or broken (in the case of cast, I guess) cams when not supported (torqued evenly in stages) on all bearing journals. Old timer VW mechanics warned not to zip the cam bearings off and on on the watercooled sohc engines but to instead do them in stages, because they had broken cams before.


I wonder if that tool is meant to go in the dead center of the cam on cyl 3 to distribute the load better, or do they specify to install it at each set of lobes that are being measured?

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You install it for each cylinder being measured. so you do this 10 times for a 5 cylinder engine, 5 each for intake, and 5 each for exhaust. I've got the tool, and your biggest problem is picking the valve tapped that is close in thickness to what you want. that is what takes time if you are installing the cams after having a valve job done. 

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