Gurgling oil tank/lines

[jonbot]

Yesterday as I was sitting in my car idling, I noticed a gurgling sound coming from the right side of the car. I presume it was the oil gurgling through the oil lines up to the front of the car, or maybe just splashing around in the oil tank. Is this normal? I ask because lately I've been experiencing some higher than normal engine temps, and I wanted to run it by you guys. The temps have not been "off the wall", just a bit higher than the half way mark on the gauge.

[cab83_750]

Normal.

Out of curiosity, what filter brand do you have? When I 'used' to use Fram, the sound was higher. I now use Mahle.

[equality72521]

Originally Posted by cab83_750

When I 'used' to use Fram, the sound was higher. I now use Mahle.

Same here.

[jonbot]

I'm using the Mahle. Glad to hear it's nothing abnormal, though now I have to hunt down the cause for the higher oil temps. I'll have at it this weekend and see if I come up with anything.

[JFairman]

I like that sound, it's one more cool thing about the character of these cars.
It's the sound of hot oil splorting out of the oil filter into the oil tank after it cycled through the front oil cooler.
When the oil is cold it's thicker so it doesn't splash about as much after being pumped through the filter into the oil tank.

Back when I worked at Gunnar Porsche, I remember the first time I took the cap off and looked into the big round aluminum oil tank in the front of a 935 while it was idleing. The oil was swirling around like a whirlpool in there because the oil inlet was offset to the side at an angle on that one.

[KTL]

Did it make this sound when you first started the car? If so, that means your thermostat is stuck open. My car has done this in the past. Right now it seems like it's stuck closed because the lines beyond the thermostat are not warming up.

[Jeff Higgins]

Originally Posted by jonbot

Yesterday as I was sitting in my car idling, I noticed a gurgling sound coming from the right side of the car.

Sure it wasn't your wife?

Like the rest have said, it's perfectly normal. My '72, completely stripped of insulation and running Elephant finned lines and widemouth cooler, is particularly noisy that way.

[bourgeois911]

Originally Posted by cab83_750

Normal.

Out of curiosity, what filter brand do you have? When I 'used' to use Fram, the sound was higher. I now use Mahle.

I had the same experience and will never use another Fram. I still have one on the shelf but I'm saving for an occasion where I want to do an oil change in a very short period.

[tcar]

Oil gurgling through the lines from the rear up to the cooler is normal. Under passenger floor.

More noticable in the fall/winter/spring when windows are up - easier to hear it.

This question comes up about every 6 months.

Never, ever, ever use a Fram filter. On anything, even for oil changes "in a short period".

Look under your car to make sure the oil lines have not been partially crushed by a floor jack or???? Could impede the flow and cause a more noisy gurgle.

[dtw]

Originally Posted by tcar

Look under your car to make sure the oil lines have not been partially crushed by a floor jack or???? Could impede the flow and cause a more noisy gurgle.

This is the first thing I thought of when reading this thread, combined with the OP's other thread today about increased temps. I'd carefully check all the tubing from front to back and then field test the thermostat.

[jonbot]

KTL: Is the solution to that replacing the thermostat? or parts inside of it? I'm considering doing this.

I'll examine the lines carefully. Also, should the trombone part be shiny brass? Cuz mine is black.

[Clay Perrine]

If you want to hear a "gurgle", drive a 914/6. In my 911, the tank is in the rear corner of the car, and the engine is between me and the tank. In the 914/6 the tank is about 8 inches behind my right shoulder. Even with the MFI at full song, I can hear the oil tank "gurgling". Actually, it sounds kinda like a toilet flushing when the engine is at full throttle.

For what it's worth, that noise is normal, and a cool part of the dry sump oiling system.

[fintstone]

Originally Posted by jonbot

KTL: Is the solution to that replacing the thermostat? or parts inside of it? I'm considering doing this.

I'll examine the lines carefully. Also, should the trombone part be shiny brass? Cuz mine is black.

If the trombone is not getting hot and your oil lines are not crushed, the problem is almost always the thermostat. You can repair the thermostat by replacing: 930-107-155-00-M322 Regulator Piston for Side of External Thermostat, 911/911 Turbo (1973-89). Our host carries them for about $41.

[KTL]

The question is, can you get the thermostat apart to replace the innards? That big slotted cap does not look like it'll loosen-up too easy.

Agreed about the temperature of the auxiliary lines as a test. If they're hot up near the cooler, the external t-stat is working.

As long as we're talking thermostats, what kind of temp. levels does one see when the internal engine thermostat is inoperable? Bigtime overheating?

[tcar]

Originally Posted by jonbot

KTL: Is the solution to that replacing the thermostat? or parts inside of it? I'm considering doing this.

I'll examine the lines carefully. Also, should the trombone part be shiny brass? Cuz mine is black.

You should check to see if the cooler is getting hot first. If it's working, all replacing the thermostat will do is lighten your wallet.

Trombone actually will transfer more heat if it's black, rather than shiny. (Unless the 'black' is a heavy coat of undercoating).

[jonbot]

KTL: The cap could pose a challenge, there's only one way to find out I'm interested in your question regarding the internal thermostat, I think that would be valuable information.