Hydraulic lifters make noise when down a quart?

[IndyIan]

Why is this? I've noticed this on a couple of cars in the past, when down a quart or a little more. The oil pressure should be the same as long as the oil pickup is submerged right? I was not driving around with the oil light on either.
Ian

 

[StevieC]

Coincidence maybe?

 

[PT1]

What size sump? If it's a small sump it could happen. Either way...your engine is talking...are you listening...

 

[oilboy123]

Originally Posted By: PT1
What size sump? If it's a small sump it could happen. Either way...your engine is talking...are you listening...

Yes your engine is talking........Are you listening little Grasshopper?

I have no clue as to why an engine would do that.........

 

[mechtech2]

Maybe the oil is hotter and therefore thinner when it is low.
Or, by the time it is low, it is simply sheared to a thinner viscosity.
Now you can sleep better.

 

[Gary Allan]

A weakening pump pulling more suction head ...perhaps

If adding a quart solves it, this seems like a plausible explanation.

I guess you can try leaving it a quart low (initially) at your next oil change. See if it still makes the noise. This won't rule out temp being a factor (though I can't really see it) ..but will eliminate any loss of visc as being a factor.

 

[IndyIan]

I should have said that I've read other places where people have mentioned being down a quart made their lifters tick. I just read a thread somewhere on bitog(can't find it now) where someone asked if their lifters were ticking while runninng down a quart.
My experience has been years ago with a 91 Escort GT(mazda 1.8 dohc). It was ticking with the oil just below the low mark, topped it up and the ticking went away.

Recently my tracker was down near the low oil mark but I didn't hear any difference after I topped it up. Its a fairly noisy engine anyways.
Maybe it is just psychological....
Ian

 

[Quest]

The only logical explanation to this (that I can think of) is that by the time when your oil is down a quart (assuming that it was fresh/full/filled to the "full" mark on the dipstick), the oil must have sheared down a bit to the point where it causes lifters to tick a bit due to thinned oil.

After adding some makeup oil to top things up (even of same viscosity grade), you might have bring the cst up a bit to the point where it no longer ticks, or ticks less.

IMHO this is more of an issue with engines that have accumulated some mileages and/or seen a bit of wear-n-tear esp. on oil pump, bing-end/rod bearing clearances,etc.

Q.

 

[mechtech2]

That 1.8 ha solid bucket tappets with shims. Maybe the splash factor to lube the cams was not so good with low oil levels.