Noisy lifter at start up

[Paul G]

I just changed the oil in my 360. The previous guy said he used to run straight 30w. Thats old technology.  I figured modern multi vis is always better.  I used Valvoline 20w50 VR1. Thier racing oil. After the change I am hearing a rap.tap.tap on start up for a few miles. It goes away as the engine comes up to temp.

The engine is built pretty darn stout. I dont have any specs on the build (I am not an engine builder by any means) but she runs out pretty strong. Feels more like a race motor than street motor. Hogged out heads and a lumpy cam, big Holley 750 on a little motor.

Should I go back to a straight weight? Or add some STP or something?

[greenpigs]

If he recomended it most likely there is a reason. Be it loose clearances or something else. If it didnt tick before the oil change I would go back to 30 weight.

[NorwayCharger]

Or, use the XPR line racing oil from Royal Purple.
Lots of ZDDP.   
I use only RP oils, and VERY happy with it.

http://www.royalpurple.com/xpr-racing-oil.html
http://www.royalpurple.com/faqs-motor-oil.html

[TylerCharger69]

I know that race motors are built somewhat  "loose"  which is why he recommended to straight 30 weight....im guessing

[FLG]

I run 15-40 in my car and have had no issues.

Before i changed it whatever it had in it i used to get a tap tap tap after sitting for a week until it came up to temp...no issues with the other oil.

[firefighter3931]

As the oil warms up and viscosity increases (oil thickens) the ticking sound goes away....makes sense based on your observations. 

If it bothers you that much simply run a single weight oil. How is the oil pressure....any changes from before ?


Ron

[Ghoste]

Doesn't the oil thin as it warms up? 

[FLG]

Thats what i was about to say ghoste....probably just a mistype.

[Ghoste]

Yeah, but it's pretty rare occasion indeed when I get a chance to yank Ron's chain so I had to take it as quick as I could. 

[Paul G]

How is the oil pressure....any changes from before ?
Ron

Oil pressure is just under 75 psi now. Before oil change it was just over 75 psi. It is just annoying to have the tap-tap-tap, as long as it is not hurting anything.

[firefighter3931]

How is the oil pressure....any changes from before ?
Ron

Oil pressure is just under 75 psi now. Before oil change it was just over 75 psi. It is just annoying to have the tap-tap-tap, as long as it is not hurting anything.

That's great oil pressure....nothing to worry about, inmo. Valvoline does make single grade race oils so that's an option if the tap-tap becomes too annoying. 


Ron

[firefighter3931]

Doesn't the oil thin as it warms up? 

Yes it does....put your thinking cap on Shawn   

Thats what i was about to say ghoste....probably just a mistype.

Nope....not a mis type 


Ok, here's the deal ; multi weight oils are designed for cold starts....we all know that. A 20/50 oil will be 20w on cold startup....cold being the key word. If that oil was a single weight and it was brought up to operating temp it would thin out which is normal. The 50w represents what a std 50 would be in terms of viscosity at operating temp....which is thicker than what a 20w would weigh at that same temp. 

So, with a multi weight oil what you're seeing is the lower value at cold startup and the larger value at hot engine temps. The 50 in the 20w50 represents what 50w would be in terms of viscosity at hot engine temps. A straight 20w oil at hot engine would be somewhat less viscous.

I thought you guys were smarter than that   


Ron

[Ghoste]

I'm still not seeing it.  I understand what you're trying to say and I understand the entire idea behind a multi-visocsity oil but I don't understand the science you're trying to explain.  What is the "magic" that makes the 20w run through a cold engine and then somehow switch to the higher one as it warms up?
All I can sya to it is that in my real world experience, when changing a cold multi weight oil, it takes a looong time for it all to run out.  But if you warm the engine up first it pours out of the pan when you pull the drain plug like it's being forced.  To me, the warm multi-weight was still thinner when it was warm than when it was cold.

[firefighter3931]

To me, the warm multi-weight was still thinner when it was warm than when it was cold.

Yep, it is thinner hot vs cold...that's normal 

  What is the "magic" that makes the 20w run through a cold engine and then somehow switch to the higher one as it warms up?

I knew this would come up.  Here's a more technical explanation of how the polymers/additives work :

"At cold temperatures, the polymers are coiled up and allow the oil to flow as their low numbers indicate. As the oil warms up, the polymers begin to unwind into long chains that prevent the oil from thinning as much as it normally would. The result is that at 100 degrees C, the oil has thinned only as much as the higher viscosity number indicates. Another way of looking at multi-vis oils is to think of a 20W-50 as a 20 weight oil that will not thin more than a 50 weight would when hot."


Think of it this way ;

-20w cold is thinner than 50w cold > easier startup
-20w cold is thicker than 50w hot > increased pour rate of "cold " oil vs. drain of "hot" oil
-50w hot is thicker than 20w hot > that's a no brainer 



Ron

[Ghoste]

So in effect, semantics takes over and both answers become right?  The physical property of the fluid remains in that it is "thinning" as it warms but your indication of the heavier viscosity polymers taking over as warming occurs is also going on.

[Silver R/T]

which oil filter are you running btw?

[skip68]

This has my head spinning.      So, what is the best oil to use ? ? ?

[firefighter3931]

So in effect, semantics takes over and both answers become right?  The physical property of the fluid remains in that it is "thinning" as it warms but your indication of the heavier viscosity polymers taking over as warming occurs is also going on.

Yep, i would agree with that. My original response was not well worded....it should have stated that as the multi grade oil inceases in temp it's viscosity will exceed the straight 30wt oil. In reference to the original question....the 30wt oil has enough "cold" viscosity to keep lifter noise at bay while the 20/50 does not....hence the lifter noise. As the 20/50 viscosity increases (even though it's thinning) it catches up and then exceeeds the straight 30w lube. Inmo, the point at which these 2 oils achieve the same viscosity is when the lifter noise disappears.

The 20/50 in effect has to play "catch-up" to the straight 30w lube.



Ron

[oldrock]

my son's 72 charger sometimes does the ticking sound on start up too. It always goes away after just a few minutes so didn't think anything of it. Is that really a problem to have it tick a little on startup? We use valvoline multi weight 15-40.

[Ghoste]

Now I get it, thanks Ron. 

[firefighter3931]

my son's 72 charger sometimes does the ticking sound on start up too. It always goes away after just a few minutes so didn't think anything of it. Is that really a problem to have it tick a little on startup? We use valvoline multi weight 15-40.

Ticking that goes away with engine temp increases (cold start > running temperature) is more of an annoyance than a problem....nothing to worry about, inmo.  

If there is a ticking noise under hot restart conditions that is an indication of other issues. Those noises (ticking) don't usually go away...from my experience. At least not without parts replacement.


Ron

[firefighter3931]

Now I get it, thanks Ron. 

No problemo buddy  Sometimes it takes a little time to wrap your head around what's actually going on inside these mechanical marvels. Lord knows i've done a lot of head scratching over the years. 



Ron

[firefighter3931]

   So, what is the best oil to use ? ? ?

Whatever oil keeps your engine from ticking ! 


Ron

[skip68]

 

[oldrock]

ty, that is what I thought but good to have some confirmation on it. It only does it with cold engine and usually only a couple mins.

my son's 72 charger sometimes does the ticking sound on start up too. It always goes away after just a few minutes so didn't think anything of it. Is that really a problem to have it tick a little on startup? We use valvoline multi weight 15-40.

Ticking that goes away with engine temp increases (cold start > running temperature) is more of an annoyance than a problem....nothing to worry about, inmo.  

If there is a ticking noise under hot restart conditions that is an indication of other issues. Those noises (ticking) don't usually go away...from my experience. At least not without parts replacement.


Ron