Hot Rods Actual oil capacity 49-53 Merc Flathead?

Ok guys, I’ve been searching a couple hours on threads here &Fordbarn. Everything says 5 quarts needed.
My engine has a canister type filter. Passenger side drain plug. Changed oil, added 5 quarts. Ran it, let it sit, dipstick says nearly quart & a half low…
Somewhere in all my searches, a guy said the mercury manual states 6 quarts.. What gives?
This whole post might sound elementary so flame me if ya want lol.
What’s everyone doing? 5 quarts, 6 quarts? Fill to full on dipstick regardless?

 

I take 5 in my 49 8BA...with no oil filter. I will say my pick-up is not real low in the pan. You obviously have a quart and a half in the filter and lines. Check the dipstick with an inspection cam the next time you drain it to make sure the dip stick and oil pick up jive, then trust the dip stick. IMO

 

I don’t have access to a camera like that. I did notice when I pulled the filter on a cold engine, there was maybe a half inch of oil on the bottom of the filter. Meaning I don’t think the canister/filter is holding much oil when drained back to the pan. Not like nearly a quart & 1/2.
Actually on the first drive of this season the other day, I checked the oil. Was about a quart low so I filled to the full line. Drove probably 80 miles. No issues.
This is my first oil change on this engine since the car was built. The first oil change was at the shop that built the car with the engine that came with it.
I went down the rabbit hole of different pans, different dipsticks until I got cross eyed.
It looks like my dipstick & pan are a pair hopefully, so I’m thinking of filling it to the mark & run it.
Thanks for the input & hopefully more will chime in on this post as to what they’re doing.

 

Asking your question on fordbarn will probably get better results.
Post clear pictures of your sump type, (didn’t know about different ones except truck sump with clean out access port) and dipstick.
top it up to dipstick level until you have definite answers.

 

In my yet to be ran fresh rebuild C59A, with the truck oil pan, at only 4 quarts it reads this. Keeping oil level “low” on initial break in. Can’t imagine any flathead requiring 6.5 quarts.

 

Your '49-'51 rear sump Mercury oil pan holds 5 quarts, 6 with the filter. The '52-'53 Mercurys used the same center sump 4 quart pan as the Fords, 5 with filter.

 

I'd run 5qt just to keep the oil changes a simple matter of dumping a jug in.

5qt in a 6qt or a 4qt pan isn't gonna matter unless you're racing.

 

The Merc. 8CM holds 5 qts. plus 1 more for the filter. Total of 6 qts. There letter "M" is stamped on factory dipstick. Easy to confuse the Ford 8BA center sump oil pan with the Merc.8CM rear sump oil pan. Easy to mismatch the dipsticks with the correct pan. Look here:
ford 8ba oil pan - Search

 

You owe it to yourself (and your car) to invest 20 dollars in your tool box.

 

Thanks for the dip stick drawing with dimensions! Good to know since there are multiple dipstick for the flatheads!

 

I had no idea such a thing existed! Thanks for posting.

 

Thanks so much for the detailed info!
My dipstick is 16 5/8 total length. It’s also not marked with an M. My pan is rear sump, but shaped slightly different than the image you posted. So, I just added the 6th quart, cold engine with canister drained back to pan. On my stick it still shows about a half qt low.
In my mind, that’s where I’m running it!
Possibly I’ve got a Merc pan, Ford dipstick?
Regardless, I’ve got 6 qts in it.
Thanks again all for the info guys.

 

It has dimmable LEDS lights and you can take pictures of what you see. Cheap tech.

 

I’ll be getting one of these. Hard to imagine that much tech for the price.
Plus I already use iPhone

 

I mean, for 20 bones, why not? Trusting a dip stick and books is a good start but for a Jackson you can find out where you pick up is mounted, where the stick is when it says "full", and take the guess work out. Plus they're fun at bars.