Dipstick markings

Hi there can someone give me some measurements for dip stick pt number 1240523 from a 1975 350 engine. The dip stick has no upper or lower level lines on it. I don't know if its been messed about with so could use the overall length and the measurements for the upper and lower levels if someone could let me know.

 

Is there not a marking line just underneath the "U"? 4 quarts (u.s.) plus extra for the oil filter, too.

 

Do an oil change, fill to correct level, mark the stick.

 

Yes it does look like a mark level with the U. Could someone please measure dip stick for me? I have a modified sump so putting 4 quarts in and marking the stick won't work for me. I do want to make sure the oil isn't too close to the crank.

 

I run a bigger pan and I had to put a mark on the dipstick after I put in 6 qts
I will get some measurements may take a day I 'll get back
Here is what I have on mine
The stick is 18" long from top ring stop to bottom of stick.
At 14 1/4" that is the full mark from top ring stop
15 1/4" is a qt low from top ring stop
The dip stick tube length is 11 1/8-11 1/4"
It reads on stick 1381751 oper range cap. 4 qts. use GM Quality MS oil.
Which I see is different than what was on your stick in the pics.
I have a 71 engine but I cannot see why measurements would be different but could be.

I have a larger pan and on mine at 6 qts the measurement is at 15 3/4 from top ring.
So on mine at 15 3/4" from top ring the oil is farther down in the pan than being a qt low on the stock pan. That would be at 15 1/4" from top ring on the dipstick. I had to remark my stick for the new deep oil pan I use.

Hope this info helps.
g out

 

Hi there thanks for the measurements. What grade of oil would you recommend ? its only a stock 1974 engine .I have had to make the oil pan slightly smaller to clear the front axel . Do you think a motorcycle oil would be a good idea because of the additives they put in the oil that give it better shear characteristics for the gearbox?

 

Right now I use Mobile 1 10-30 and mix in the same 15-50 of 2 qts. and 4 qts of the 10-30
I have done this forever and motor still looks good.
The 15-50 Mobile 1 has zinc in it but the 10-30 does not. So far I have been ok with the cam but it has been in there since early 2000.

There is a article in here about the oils on another thread. But I would use a 10-30 oil and if the pressure is a little low put in a qt of 15-50 or equiv. You can't put thick oil in the engine it is too hard on the oil pump especially if there was no mods done to the timing cover and the oil galleys in the engine.

I have had this engine and car since 77 and I always ran 10-30 even when I did not have anything done to the motor when it was stock and I ran the hell out of it back then.

I would not use the motorcycle oil it is probably different
Regular oil with some zinc added will be all you need stock engine 10-30 best bet

 

I was taught not to mix oil grades, as they separate when sitting in the crankcase? Anyone else have thoughts on this?

I run Mobil 1 also, but currently use the 10w-40 variety. Both my Buicks are as stock, and they don't really see big loads or high RPM (No racing). The inside of my 350 looks ok with about 45k miles since it was rebuilt, but there was more carbon on the drivers side valve train then I like... Still sounds good and runs smoothly, makes good power too.

 

Thanks for the replies .I have found this oil test on the site gives some interesting results showing that its not just the ZDDP additives in the oil that are required but also very much the quality of the oil used .Lots of oils in the tests had higher amounts of ZDDP but performed worse than oils with less ZDDP. http://forums.pelicanparts.com/911-930-turbo-super-charging-forum/1028884-oil-test-zddp.html