Oil level

[Jon Schmid]

OK, I have a 1960B T-5 1600 Super engine and a 1964 C engine in my cars. The engines should be pretty much the same. The Driver's Manual for the Super says to shut the engine off and then replenish the level, preferably to the top mark on the dipstick, which tells me the level is measured just after the engine has been run. The C manual says to shut the engine down and then wait until the oil has had time to drain back into the sump and then take the reading. For engines that are so similar, this seems a bit contradictory. Or is it?
Thanks in advance for any input.

[Mike Wilson]

Hey, Jon:

I've always heard that the oil level should be checked with the engine cold and the level should fall between the two marks on the dipstick.

If I am in error, PLEASE correct me so I don't look like a dipstick!

Mike

[Jon Schmid]

That's my question, Mike. Measure warm or cold? I'm leaning towards warm because I know the level drops quite a bit depending on when you check.

[David Jones]

Check it cold and top it up if it is lower than midway between the two marks, then check it hot and make a note of where it is then you will know where it should be when hot. Remember that once the engine has been run the oil cooler is full of oil and that has to run down in to the case to show the true level, which is why you should not top it up when hot unless you know where the hot level should be. If you top it up when it is hot to the top mark you will now have a level of oil that is going to be too high for normal operation and can cause overheating.
My boxster for instance has an oil level indicator that takes a varying amount of time to show a stable acceptable level. When I turn on the ignition when engine is cold the level indicator reads immediately but if I start the engine then turn it off it will start a countdown until it reads which when cold can be many minutes. When hot it is maybe 15 seconds before it reads.
I still remember the line from the "How to keep your Volkswagen alive" book by John Muir which admonishes the reader to always wait 5 minutes after hot shut off before checking oil level. In fact he suggested taking the "old lady" in to the back of the VW bus for some minutes of recreation before checking the oil.

[Mike Ruddy]

I've been measuring my oil level with the engine ruining as per early 911s.

[Mike Wilson]

Hey, Jon:

From the B driver's manual under "Checking Engine Oil"
NOTE
"After starting the engine, the oil is drawn from the sump and forced through the oil galleries to the various lubrication points. After turning the engine off, the oil from these passages does not flow back into the crankcase sump immediately and will therefore show a dip stick reading which is slightly different than one which is taken sometime later. The correct reading is taken when the oil has had a chance to return to the sump. This means that the maximum oil level during operation should be somewhat below the upper mark on the dipstick. A reading of 10mm (1/2 inch) below the top mark does not require filling up.

1. Remove dip stick when engine is stopped (see above) and wipe clean.
2. Reinsert dip stick into the crankcase.
3. After a short time (5 seconds) pull out the dip stick and read oil level. The oil level should always be between the two markings and oreferably bear the upper mark.
4. If neceassary, fill oil level to upper dip stick mark. One liter (1.1 quart) will bring the level from the lower mark almost to the upper mark."

Mike

[Jon Schmid]

I've been measuring my oil level with the engine ruining as per early 911s.

You drain the oil and then run it? JK The T5 manual never mentions "hot," just shut the engine off. That's why these Driver's Manual recommendations are a bit confusing between the two models.

[David Jones]

Mike do not confuse a dry sump engine like the 911 with a wet sump engine, totally different requirement.

[Martin Benade]

I think the B manual just had a carelessly written instruction on checking the oil. When they did the C manual, they tried a little harder to get it right. Accepted practice for all wet sump engines is after the engine has been sitting for 5 minutes or so. If you are concerned with the difference between 5 minutes and overnight, you shouldn't be. It is important to have "enough" oil but the exact amount is meaningless. That is why there are 2 marks, between them is acceptable.

[Jon Schmid]

Hey, Jon:

From the B driver's manual under "Checking Engine Oil"
NOTE
"After starting the engine, the oil is drawn from the sump and forced through the oil galleries to the various lubrication points. After turning the engine off, the oil from these passages does not flow back into the crankcase sump immediately and will therefore show a dip stick reading which is slightly different than one which is taken sometime later. The correct reading is taken when the oil has had a chance to return to the sump. This means that the maximum oil level during operation should be somewhat below the upper mark on the dipstick. A reading of 10mm (1/2 inch) below the top mark does not require filling up.

1. Remove dip stick when engine is stopped (see above) and wipe clean.
2. Reinsert dip stick into the crankcase.
3. After a short time (5 seconds) pull out the dip stick and read oil level. The oil level should always be between the two markings and oreferably bear the upper mark.
4. If neceassary, fill oil level to upper dip stick mark. One liter (1.1 quart) will bring the level from the lower mark almost to the upper mark."

Mike

Mike, that's also the verbiage out of my 356C manual. The B T-5 manual I have printed 9/59 (page 43) reads:
1. Shut off engine (the manual doesn't specify a run time)
2. Pull out and clean oil dip stick (see fig. 30)
3. Insert dip stick to stop
4. Wait a few seconds, pull out dip stick and read oil level which should be max. at the upper, and min. at the lowest mark on the oil dip stick.
5. If necessary add HD-oil to the upper mark on the dip stick.
Maybe you have a B T-6 manual?

[Mike Wilson]

I do have the T-6 manual, Jon. I think it's dated 1/63.

All the best,

Mike

[Mike Wilson]

Same language verbatim in the 1/63 B manual and the C manual dated 9/63.

Mike

[Ron LaDow]

Or, when the light comes on in hard cornering, add a pint or so....

[Ron LaDow]

Or, when the light comes on in hard cornering, add a pint or so....
Actually, make it precisely 16oz,'cause you know...

[Mike Wilson]

Well that makes it simple! Green light = add oil! Ha!

Thanks, Ron!