Oil level on dipstick

[dale_z28]

Ok, I want your opinions. As I was taking delivery of my newly-restored car, the guy that did the mechanical side of the job gave me a list of details including when it would be time to change oil....in 200 miles. He said depending on the type of oil filter I choose (typical car filter or the higher-capacity truck filter), I should mark the dipstick where the oil level falls after I've added 5 quarts and warmed the engine enough to circulate it. His thinking is that with the additional oil in the filter, my "full" mark would be below the factory full line on the stick, which I agree with. But where I tend to disagree, is that adding oil to bring it to read "full" is, in his eyes, too full - as in the crankshaft slinging oil - full. I can't picture this. First, there is a windage tray separating the crank from the oil; but more importantly (in my mind, anyway) is that the "extra" oil is in the filter, not the crankcase. An analogy that plays in my head says, if the filter held 3 quarts (an exaggeration), then there would only be 2 in the pan to be picked up by the pump, etc.
We may be talking an amount so small that it doesn't even show on the dipstick; it's more me trying to wrap my head around what point he's making with recording the "true fill level" on there.  Any thoughts?

[Mike S]

  Your thought is correct, IMO. The way I see it is the oil is either in the filter or sump. If it were my car I would go by the dip stick reading because that is measuring the level in the sump regardless of the filters capacity. If it's at or below full then it should be fine. Also, as you mentioned, the windage tray should keep the crank from hitting the oil and causing possible foaming and that would most likely be when overfilled and possibly turning to cause the oil to surge to one side thereby elevating it.

Mike

[Tedramairii]

The larger the filter the better, the more paper there is to filter the oil. What he is saying is that the larger filter may hold more oil. The oil level is the oil level, just be sure the dipstick shows FULL. The oil pan doesn't know how big it is, or how much the filter holds, but the dipstick knows where the full line is.

[BULLITT65]

Thanks Ted.

(Welcome to the site  )

[bcmiller]

Dale I would check back with the guy that assembled the engine. You may not have been on the same page.

I assume the engine is a fresh rebuild and that it is in its break-in period. What does the dipstick show now? I bet it is on the full line.

What he was probably trying to get you to do is to see what level the oil was on the dipstick with 5 quarts added (when you change the oil). It may need closer to 5.5 quarts to be full, but you need to check.

For example, with the pan and filter that I have, it takes a little under 6 quarts to be full.

[Stingr69]

The dipstick measures the level of oil in the pan. That is all that matters.  The filter could be big enough to hold 50 gallons of oil and you would still need the "full" mark on the stick to read full.

Oil level much above Full and the spinning crankshaft can froth up the oil.  Oil level significantly below Full and the pickup could run dry and the engine would loose oil pressure.

[Fanthomgreen69]

I also show about a 1/2 qt. low after oil/filter change. I use a Wix 51069 filter which is what the Wix catalog shows. Thought I might have the wrong filter, dipstick or dipstick tube. Even a 6 qt. pan. The manual even shows 5 qt. capacity with filter change. Didn't want to over fill, so showing 1/2 qt. low I know I have 5 qts. Still would like to see the level up to FULL, but don't want to damage the engine.
Charles

[dale_z28]

His remark was to ensure I didn't overfill the oil, but regardless of filter capacity, unless somehow the pump can run the filter out of oil and then "overfill" the pan, I don't see why I would want any less than to the "full" mark on the stick. Thanks for the input.
I agree, Ted, I run the larger filters, too.

[ko-lek-tor]

Your mechanic is full of cr&$. If that is his belief, I wouldn't want him touching my engine. That mark on the dipstick is where you fill it regardless of filters, deeper pan, remote oil cooling or a host of other scenarios. Like a carburetor float, you want to maintain an ideal level. that is the level the oil needs to be to insure adequate quantity of oil is available to the oil pump pick up.
As far as the engine builder wanting you to get a reference to know how many quarts to add, believe me, you will know when you change the oil and check your dipstick until it is on full, then you will know how much it holds.
Here is a good article on filtration & bypass systems. http://www.machinerylubrication.com/Read/29026/engine-bypass-filtration

[cook_dw]

Your mechanic is full of cr&$. If that is his belief, I wouldn't want him touching my engine. That mark on the dipstick is where you fill it regardless of filters, deeper pan, remote oil cooling or a host of other scenarios. Like a carburetor float, you want to maintain an ideal level. that is the level the oil needs to be to insure adequate quantity of oil is available to the oil pump pick up.
As far as the engine builder wanting you to get a reference to know how many quarts to add, believe me, you will know when you change the oil and check your dipstick until it is on full, then you will know how much it holds.
Here is a good article on filtration & bypass systems. http://www.machinerylubrication.com/Read/29026/engine-bypass-filtration

X2  Not sure how I missed this thread previously but find another engine builder/mechanic if he doesn't understand oiling systems..  As long as the stick is the correct one for the pan I dont care if you have a 14 gallon oil filter on the car you fill it to the full line on the stick.

[z28z11]

One more consideration - 302's had a high volume/high pressure pump (not sure what relief spring without looking), but I used to have 80 psi and up on the Stewart Warner mechanical gauge in the front cam gallery plug with Union 20W50 racing oil, standard Z pan, windage tray, original cam, lifters, blue tips and service manual bearing clearance. At that volume, over 80 psi can pull a lot of oil out of the sump in a hurry, pushing it to the top of the motor. You sure don't want to cavitate the pump by running too low of a pan level - a couple of hiccups, and you'll be barfing expensive bearings and wiping out expensive cranks. I've seen the evidence many times. I've kept my original pump all these years, might re-install it if the gears and clearances check. Keep it between the lines - always. 

Regards,
Steve

[69Z28-RS]

Something else to keep in mind if you are rebuilding a Chevy engine is 'oil drainback'... As soon as your oil runs off the rockers, you want to get it back into the pan/sump as quickly as possible.   A large impediment to this is casting flash in the drainback corners of your heads; whenever doing head work, be sure to grind out all the casting flash from these areas.  Something else I like to do is to 'paint' the cast surfaces which also aids in drainback, as well as capturing any particles from the sand casting.

[ko-lek-tor]

Z28z11 aka Steve , re: reply 10, " 302's had a high volume/pressure pump. " 302s had high pressure, NOT high volume.

[dale_z28]

Thanks, guys. Your opinions reinforce mine. The guy turns out to be a contractor, at least as far as engine work goes. He subbed out my engine work to another reputable guy that I trust, but he's the one that took my money and will take the heat if there is a failure.

I'd never heard of the "mark your dipstick" routine, and wasn't planning to follow it unless someone else could substantiate it. All of you made good points, and I appreciate the feedback.