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Do these valves seem especially noisy to you?
https://www.slantsix.org/forum/viewtopic.php?t=46686		 Page 1 of 2
Author:  Griznant [ Mon Oct 17, 2011 6:14 am ]
Post subject:  Do these valves seem especially noisy to you?
I need advice.

The long and short of it is that after spending a lot of time sorting out leaks, timing, etc, I finally have the "built" slant running in my '82 Ram. The engine seems to be VERY strong, but due to some latent items to fix, I haven't driven it yet. I have thoroughly adjusted the valves, first statically when it was put together, and secondly while it was running. I have lash set at .010" intake, and .020" exhaust. There seems to be an exceptionally large amount of valve clatter and I need to know how worried I should be.

The engine is a '77 225 that has been extensively reworked. The cam and lifters are the stockers that were reground by Oregon Cam to their 818/819 grind combo. I am running oversize stainless valves, and the head is fully reworked. Stock rockers and pushrods with new springs that have 90lbs installed seat pressure.

I have good oil pressure, and oil is visibly running out of the rockers when running. Oil is Shell RotellaT 10w-30w.

I have read that changing to a thinner oil will help. Also, that maybe I should tighten up the lash and see where that gets me. Maybe I'm worried about nothing, but it seems to clatter an awful lot. The stock engine was a hydraulic motor, so maybe I'm just being overly cautious by comparing the two.

If you could give these videos a listen and let me know your thoughts, I'd greatly appreciate it.

http://www.youtube.com/watch?v=TdCVwTWu ... ture=feedu

http://www.youtube.com/watch?v=KramKzqu ... re=related

Thanks,

Grant
Author:  ceej [ Mon Oct 17, 2011 6:43 am ]
Post subject: 
What is the lash set to?
I show .010" and .012" for that grind.

It does sound loud.

CJ
Author:  Griznant [ Mon Oct 17, 2011 7:43 am ]
Post subject: 
.010 intake, .020 exhaust.

I'm going to tighten them up and see what happens. It just seemed a bit excessive to me too.

I also didn't know if I should run a tighter lash with the stainless valves given different thermal expansion compared to the stock steel ones.
Author:  USAJon [ Mon Oct 17, 2011 8:48 am ]
Post subject: 
you've got something hitting something somewhere.
Author:  Joshie225 [ Mon Oct 17, 2011 9:05 am ]
Post subject: 
I hope that's an 819 lobe on the intake side and 818 on the exhaust. Slants make more power with more intake duration.

That is loud compared to a stock mechanical cam. Oregon recommends the lash at .010" intake and .012" exhaust. That might be slightly tight on the exhaust, but probably not by much. One 'tell' is to run it hard and see if it still idles smoothly. If the idle gets rough after a hard run and it idles well with more lash then you need to run more lash.

The idle speed seems a bit high. USAJon brings up a good point. Is it this loud with the valve cover off?
Author:  Griznant [ Mon Oct 17, 2011 9:23 am ]
Post subject: 
Quote:
I hope that's an 819 lobe on the intake side and 818 on the exhaust. Slants make more power with more intake duration.
It is.


Truthfully, I don't remember if it was less noisy with the cover off. I don't remember that being the case, but I'll check tonight and see. As for anything "hitting", I don't know what could. I've literally turned this engine over hundreds of times by hand, and then on the starter before I actually started it up and didn't notice anything binding or hitting. I can bump the idle speed down, I just had it cranked up a bit when I made the video since the throttle cable isn't connected and everything is just by feel at this point.

I'll pull the cover tonight and see if I can see anything that may be interfering.

Thanks for the help!
Author:  Reed [ Mon Oct 17, 2011 9:42 am ]
Post subject: 
This has nothing to do with valve noise, but where is your PCV valve?
Author:  63valconvert [ Mon Oct 17, 2011 9:55 am ]
Post subject: 
That's a lot of clickity, especially for that clearance. If they were loose, I would say that sounds about right.

Your answer to the PCV question will be an important one, though.
Author:  SlantSixDan [ Mon Oct 17, 2011 10:02 am ]
Post subject: 
10w-30 isn't hair-raisingly wrong, but it's kinda heavy for a brand-new engine. I'd be running 5w-30 or 0w-30. But oil selection isn't going to change the noise.

The stock valves were stainless steel, not regular steel.

This sounds louder than it should, but not evenly so. I think you've got some interference under the valve cover. These Chinese chrome valve covers are notoriously problematic; you'd be much better off with a stock cover. You'll get to find out what might've been hitting the underside of this cover when you pull it off to re-set the lash.

And yeah, you need a PCV valve.
Author:  Griznant [ Mon Oct 17, 2011 11:54 am ]
Post subject: 
Don't have a stock cover. The original engine was a hydraulic motor and the cover wouldn't fit the mechanical core motor I bought, which conveniently didn't have a valve cover. So, since I had to buy one, I got the super-fancy chrome one. I'll see if it's hitting when I pull it off.

I do not have a PCV on this thing yet. The cheapo valve cover had two holes in it: one that I stuck a breather in, and one that I stuck the oil fill in. I assumed I would have to modify it for a PCV once I got everything figured out. The truck is not yet drivable so the only running that it has had has been in the driveway to break in the cam (followed by an oil change) and a few run-ins since to adjust timing/valves/and fix some oil and exhaust leaks. Very little actual use, and none under load.

I ran the RotellaT 10W-30 because I wanted the added zinc for the break-in and it was the lowest viscosity available in that brand. I've had good luck using that oil for intial run-in with other "old-tech" engines so I didn't think something as thin as 5W or even 0W would be acceptable at this stage, and especially never breaking in with full-synthetic.
Author:  USAJon [ Mon Oct 17, 2011 12:18 pm ]
Post subject: 
put your hand on the valve cover while it's idling..

I would not run it until your trouble shoot/resolve the issue..
Author:  SlantSixDan [ Mon Oct 17, 2011 12:48 pm ]
Post subject: 
Quote:
Don't have a stock cover.
You'll be better off getting one.
Quote:
I didn't think something as thin as 5W or even 0W would be acceptable at this stage
You've got it backwards.
Author:  Reed [ Mon Oct 17, 2011 1:02 pm ]
Post subject: 
Someone in the greater Chicago area MUST have a 70s era valve cover they would sell you. And if you can't find one locally, I have one I would consider selling for the right price.
Author:  Griznant [ Tue Oct 18, 2011 4:09 am ]
Post subject: 
Ok, so this what I know now:

The valve cover isn't the issue. There is nothing actually interfering with anything under there, and nothing is hitting or rubbing.

What I DO have are amazing self UN-adjusting rockers. Several were in various stages of loosening up, and at first I thought "Crap, the cam is going flat", but upon closer inspection, most of the adjusters have just worked themselves "up" and the lash was all over the place. I'm surprised it did this within, literally, 20 total minutes of running since I adjusted them (while it was running).

So, I see another thread is conveniently covering this topic right now. Looks like I'll need to see what I can come up with there!

Thanks for the help, and hopefully I'll have a "happier" update soon!

Grant
Author:  Sam Powell [ Tue Oct 18, 2011 4:56 am ]
Post subject: 
Was it quiet at first, and then get noisy with running? Those adjusters should be hard to turn. Can you put a wrench on one with a valve closed and get a torque reading? Maybe some one with an open motor that has good rockers on it could do the same and report back with a normal torque spec.

My concern is that it is not the rocker adjustments that are changing.

Sam
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