My stock 1.7 has an extra mark below the low mark on the dipstick. The original full and low marks are where they should be - 30 mm and 23 mm respectively from the end of the stick.

Mine has an additional one, about 17 mm from the end.
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Any guesses about what possible purpose would a prior owner have had in making this mark?

I have not seen it on other dipsticks.

Unfortunately, I have been using it as the low mark for determining when oil is needed — until measuring it today — but no more! No telling what damage may have occurred from running too little oil for this long.

PO must have added it to show when oil was a full quart low. The original low mark is when oil is I think around 2/3 to 3/4 of a quart low (which is kinda stupid).

Ansbacher

I wondered that too, but didn't want to believe that adding oil only when a whole quart low might have been his normal practice. Also, if you add a quart when it is at that line, the sump is overfilled above the full mark.

Over filling up to a half quart won't damage anything, it's not uncommon for racers to do that to keep enough oil in the sump in hard cornering.

I'd rather have a little too much than a little below the mark. I don't think I'd want to go very far with a quart low in a 914. It's not like a 6 or 911 where you've got 10+ quarts in the system

I have been meaning to ask the question what is wrong with having the oil above the line by about a 1/2 quart - my son put the whole bottle in when we were on the lower line, we are now a bit above the line - thanks for the information!

Check your owners manual about the dipstick marks.

It's a bit too much, when you overfill it's about 250ml (half pint), or adding an amount that's just under half of the distance between factory marks.

Right, did that. It says there is 2.1 pints between the upper and lower marks. So, I would add that much when the level was at the "middle" mark and it was overfilled quite bit. That led me to conclude that the lower mark on my stick was the factory mark and the "middle" mark on my dipstick had been added by a PO. Now today, after measuring the marks on my stick from its end, and comparing the distance to this photo from a prior post of "larss", I see that my conclusion was incorrect -- and, the manual overstates how much oil is between the 2 factory marks, at least for my engine.
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