The Case of Disappearing Oil, What happened to the oil level? Options

[DrinkMan]

There were a few witnesses to this event during the Oketeenerfest Scenic drive. We were driving in the group when we entered the Foothills Parkway entrance ramp curve in 2nd gear when all of a sudden, our engine made a knocking noise. I immediately upshifted and the noise went away but our oil pressure had dropped from 20 psi to less than 10 psi (maybe even 0, I didn't take the time to study the gauge). I quickly shut down the engine and pulled over. Thankfully, everyone in the group pulled over with me to help.

I pulled the dip stick and the oil was only at the bottom of the dipstick. Very low. WTF? I had 2 partial qts of Driven DT50 on board (I thought when we left home that one was full and the other 1/2, but not really). I poured both in and all I got was the oil up to the lower line. Luckily, a GREAT Samaritan in the group has some Swepco 201 and I used it to fill to top. I accidently went a little over the line but no way to lower it on the side of the road. I think I put a total of between 1 and 1.5 qts. At the time, I thought 1.75 qts but when I returned the Swepco to the the Samaritan, I noticed I had not used very much of it (I had found some oil locally to put on board just in case).

Background - Engine is a 2056 installed by previous owner ( @iankarr ) about 8000 miles ago. We have not had any oil issues whatso ever. Probably top it off a little bit to keep it on the upper line (typically 1/2 the way between upper and lower line) once between oil changes (about 2000 miles per change). When engine is warm, oil pressure runs between 20 and 40 psi (cold, higher pressure, up to 70 on cold days, cold engine). Seldom below 15 psi (over 220 degrees oil temp in very hot south Ga weather after a long high speed drive).

Before we left North Ga to attend Okteenerfest, I checked the oil. Exactly on upper line. We had a fun drive to Townsend (Blood Mtn 129 and Tail of the Dragon). Then drives to Maryville, local mtn roads and to Pidgeon Forge. Filled up gas in Pidgeon Forge at 250 miles +/-. I thought I checked the oil level because that is a habit at every gas stop but I keep doubting myself based on this event. The oil pressure dropped happened at about 120 miles +/- so we had driven about 370-380 miles since I can guarantee the oil was full.

Multiple 914 owners studied the engine and saw no drips or staining. No one following me up to that point had noticed any blue smoke from exhaust. After I filled it up and drove back to the hotel (no unusual engine noises), I was told there were some minor puffs at gear changes but nothing bad. There is a mechanical gauge on the engine and it showed 35 psi when we restarted the engine after topping it off but I checked the gauge later and it always reads 35 psi, even when engine is off so I'll need to replace that. When I took off after topping off the oil, gauge on dash went back to the usual 20 to 40 psi. BTW - at no time did the oil pressure light come on.

We now check oil level every time we park. Oil is the same. So after driving home (we stayed over in Townsend a few extra days to relax) with the same route home (Tail of the Dragon and Blood Mtn 129 again) and 380 miles from when the incident happened. Same level.

What happened to the oil? Mike ( @Dr Evil ) theorized that our oil filter had been on bypass for the last 1000 miles and when we were going around the curve, it opened up and filled up the oil filter for the first time since we changed the oil about 1000 miles ago.

Here is how our dip stick looks now. Exactly like 380 miles ago up on the Scenic drive.

(IMG:http://www.914world.com/bbs2/uploads_offsite/live.staticflickr.com-20872-1726779901.1.jpg)

I welcome all the comments and abuse, especially the witness at Okteenerfest that can pile on.

[Shivers]

it always reads 35 psi, even when engine is off so I'll need to replace that

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[DrinkMan]

I forgot to mention that we plan on running a compression test soon. If anything is strange, then a leak down test. I had planned to do that today but got tied up working on the TR6 muffler.

[brant]

The oil sloshes a lot in the corners with a type 4

On track. Oil pressure drop or zero is common on a stock motor
The best cure (as no oil pressure is extremely bad) is to add a tuna can to the sump

This slang name “tuna can”
Lowers the pickup point of the engine
Creates a small reservoir down low that doesn’t slosh as much
Can solve the pick up problem


There are deep sumps and accusumps that also solve this g-force slosh problem. But the tuna can is simple and cheap. Works also


As for where did the oil go
It probably burned

Also at times the dip stick will appear low if there has not been adequate time for the oil to drain back to the sump


Meaning it might look low on the stick 30 seconds after shutting the car down. But can appear higher on the stick if given 3 minutes to drain back

[Geezer914]

I always fill the new oil filter with oil when doing an oil change.

[SirAndy]

I always fill the new oil filter with oil when doing an oil change.

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[DrinkMan]

I also fill the filter but as you can imagine, I'm doubting everything I do because I do so much by rote while maintaining the fleet.

[DrinkMan]

The oil sloshes a lot in the corners with a type 4

On track. Oil pressure drop or zero is common on a stock motor
The best cure (as no oil pressure is extremely bad) is to add a tuna can to the sump

This slang name “tuna can”
Lowers the pickup point of the engine
Creates a small reservoir down low that doesn’t slosh as much
Can solve the pick up problem


There are deep sumps and accusumps that also solve this g-force slosh problem. But the tuna can is simple and cheap. Works also


As for where did the oil go
It probably burned

Also at times the dip stick will appear low if there has not been adequate time for the oil to drain back to the sump


Meaning it might look low on the stick 30 seconds after shutting the car down. But can appear higher on the stick if given 3 minutes to drain back

It took over a quart to get back up the stick. And we had been doing a hell of a lot more cornering at much higher speed without incident.

Clay Perrine suggested the tuna can as well at Okteenerfest and I plan on ordering it tonight when I get sick of troubleshooting a 51 year old TR6.

[wonkipop]

did you pull up on dead flat ground on the side of the road where you were first checking the oil level and getting the low reading on the stick.

it can make for a bit of a difference in an AC VW engine.
also sometimes you think the ground is flat and its not really. deceptive perception.

[windforfun]

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[Dr Evil]

I had my suspicions about your oil filter as that amount makes sens. The circuit may not have been active/sticking and when it finally opened it dropped your level.

[DrinkMan]

did you pull up on dead flat ground on the side of the road where you were first checking the oil level and getting the low reading on the stick.

it can make for a bit of a difference in an AC VW engine.
also sometimes you think the ground is flat and its not really. deceptive perception.

It wasn't completely level. As level as could be found when i turned off the engine and just coasted. As soon as we came down off the hill and got to the hotel i parked in a level spot and the dip stick looked just like it does in the picture taken 380 miles later. And since I added that qt + on the drive, I've checked it about 20 times (every time I shut off the engine and get out of the car.....yes I wait for it to settle). Even the crazy of checking it when we parked at home and then the next morning when cold. Since I added that oil and it made such a difference, we know that it was low (about 1.5?).

Compression test planned for next time we can get to it. We have to go to the Fall Historics at Road Atlanta Fri-Sun so it may not get checked until Sunday afternoon. Luckily, we have plenty of other cars to take to Road Atlanta so it can sit and relax after the week in Townsend. It is number 2 on the list to work on (still troubleshooting TR6 and it is taking up the mental space and our maintaince bay in the garage).

[VaccaRabite]

Do you have head vent breather tubes set up on your car going to a catch can or into your intake to be burned?

Your heads will pump a lot of oil up the tubes, especially under hard cornering. Especially bad when you are already sloshing oil away from the pickup tube.

Zach

[DrinkMan]

Good catch (pun intended). Our catch can is on the shelf not on the engine. We know that when we push it hard and corner that we get some coming out there. But there was no excess oil (over a quart would be noticeable) on the engine.

So thus far - Need to install the catch can and get a tuna can.

@Dr Evil theory of oil filter bypass still has a lot of potential.

Compression test to help figure out if it is getting burned.

My wife was wondering about the valve cover gaskets. Because after a valve adjustment a few months ago, I had a leak (we were looking after the adjustment and caught it quickly) and fixed it. But her point is that maybe we have a small drip that went unnoticed.

Nothing except the oil filter bypass explains the seemingly sudden drop and keeping the oil fine ever since.

Do you have head vent breather tubes set up on your car going to a catch can or into your intake to be burned?

Your heads will pump a lot of oil up the tubes, especially under hard cornering. Especially bad when you are already sloshing oil away from the pickup tube.

Zach

[VaccaRabite]

If your head breathers are currently capped, i'd leave them that way.

Its not going to be valve cover gaskets. If they were dripping enough oil to cause your problem, the car behind you would have not only noticed, but would have had oil spatter on the nose and windshield.

I've driven behind a 914 with a significant oil leak - my car was a MESS afterwards!

I like Mikes theory, but the filter holds about 1/2 quart, so you still lost another quart on top of that. Do you have any sort of AUX oil cooler? They usually attach via a sandwich adapter between the oil fiiter and the case. If THAT had to fill, you would certainly see the drop in pressure and "lost" oil.

An AUX cooler is common on 2056 and larger engines.

Zach

[iankarr]

Very strange. If you checked the oil level shortly after shutdown, I agree with Brant that the "missing' oil hadn't yet drained back down. It might've been a bit low to begin with and the pressure drop happened in the corner from centrifugal force exposing the pickup tube. It could be a combinaton of curves or a very long curve that created a unique situation. Otherwise, Mike's theory, or some variation of that, seems the most likely so far. What did the knocking sound like and how long did it last?

Jake Raby doesn't reccommend pre-filling the oil filter when doing a change since air isn't efficient at pushing oil through the circuit, but of course there's debate on that. Here's a thread:

http://www.914world.com/bbs2/index.php?sho...p;#entry1595700

Mark Henry as well.

http://www.914world.com/bbs2/index.php?showtopic=358747

[Geezer914]

I think the jury is out on filling up the oil filter. I would think the more oil you have in the system, the faster the oil pressure will build up. When the engine is shut off and the oil drains back to the sump, the oil does not drain out of the filter. The only engine I have seen with the oil filters mounted upside down is Ferrari. I'm still going to fill my filter when changing my oil.

[DrinkMan]

Very strange. If you checked the oil level shortly after shutdown, I agree with Brant that the "missing' oil hadn't yet drained back down. It might've been a bit low to begin with and the pressure drop happened in the corner from centrifugal force exposing the pickup tube. It could be a combinaton of curves or a very long curve that created a unique situation. Otherwise, Mike's theory, or some variation of that, seems the most likely so far. What did the knocking sound like and how long did it last?

Jake Raby doesn't reccommend pre-filling the oil filter when doing a change since air isn't efficient at pushing oil through the circuit, but of course there's debate on that. Here's a thread:

http://www.914world.com/bbs2/index.php?sho...p;#entry1595700

Mark Henry as well.

http://www.914world.com/bbs2/index.php?showtopic=358747

You and I had a "conversation" offline but just to fill everyone in, it sounded like a starving oil pump.

This was also not the first sloshing of oil during cornering. But usually resulted in smell, not noise and drop in pressure. Haven't done compression test yet but did some driving today to Road Atlanta including some heavy throttle. No meaningful blue smoke (actually my wife behind me did not see any). And oil level still holding steady. Close to 500 miles now since the incident without any drop in oil level. Wonder where that quart (or 1.5? Damn i wish i had paid more attention to exactly how much oil i added) is? If all the theories about measuring too soon or on a hill applied, we would be a 1 to 1.5 quarts too high. Must have dripped it, burned it (one time burn), or filled the filter. Now my normal oil paranoia with our old cars is multiplied.

[bkrantz]

Tuna can worked great on my SCCA/PCA 914 race car.

[DrinkMan]

I think the jury is out on filling up the oil filter. I would think the more oil you have in the system, the faster the oil pressure will build up. When the engine is shut off and the oil drains back to the sump, the oil does not drain out of the filter. The only engine I have seen with the oil filters mounted upside down is Ferrari. I'm still going to fill my filter when changing my oil.

Our Lancia Fulvia has the oil filter on top upside down like the Ferrari.

Funny story about that oil filter. As per usual, on the forums there are arguments about which filter is best. Discussion about the bypass spring, number of folds, etc... I was trying to decide which to buy and realized that I could just buy the "official" one on my Lancia parts supplier website rather than a brand name from an auto parts store. While I did not like the $40 price tag, it is only an annual expense. So I ordered it from that supplier. It had an Italian brand and unique part number - same as original factory. About 10 minutes after I ordered it, the order was cancelled. Then my phone rang. It was the owner of the Lancia parts store. He had helped me find my car in Italy and was a complete Lancia enthusiast. He told me not to buy his filter. He told me that the filter he sold from Italy was simply an American brand filter (he provided the part number as well) that they painted a different colour, put the other brand on it and shipped it to Italy. I went to WalMart and found the exact filter for $4. Since I wasn't a fan of that brand of filter, I checked cross reference charts and found a brand I liked and have been using that since.