Oil Dipstick Length Question

[jchiotti]

Hello,
I was hoping for some advice or help with a dipstick question. I purchased a 226 1985 seafarer that needs some work, but everything has gone pretty smoothly so far. I started the engine up the other day to change the oil. It seemed like there was quite a bit of oil that drained out (more than recommended) but I didn’t measure it. Now looking back, I wish I did. The engine is a MCM 200 V8 305 CID (serial #6899083; see picture). Based on the engine specs it says that the engine should take approximately 5 qts of oil. So I dumped five qts in. I checked the dipstick and nothing showed up. I started the engine to see if it may then show up on the dipstick. It didn’t. I was able to fabricate a dipstick and noticed that the oil level was about 2” below the bottom of the dipstick that was in there. I thought....no way am I adding that much oil as I am sure it would take much more than recommended to reach the dipstick full line.

So...I called a Mercruiser mechanic, explained what was going on and they said, “I would just order a dipstick and cut it off to the 5 qt mark since that is what you put in and know how much is there”. The thought was that someone just put the wrong dipstick in there over the years. So that is what I planned on doing until I saw this website (https://www.nlamarine.com/products/...ck-oil-level-gauge-pan-v8?variant=10560302021) that shows my dipstick (96822; even though mine has an M at the end of the number) that fits the motor on my boat.

So now I was thinking that the dipstick was correct....just why does my 5 qts of oil come no where near the bottom of the dipstick. Does anyone here have any advice or similar motor that they could measure the length of their dipstick to see how long mine should be?

Motor/boat is one concrete should be close to level.

Thanks in advance for any help.

 

[DennisG01]

Either you didn't notice the oil on the stick because it was clean (sometimes hard to see as it's nearly transparent), didn't insert it all the way, you still have the wrong dipstick, or someone replaced the dipstick tube and it's too long.

If it's not one of the first two things, you might be best off to talk with a local Merc dealer - or, even better, stop in to their store and talk with the parts department directly.

 

[Halfhitch]

You said you bought the boat used so depending on clearances, a previous owner could have installed a high volume oil pan or as mentioned could have replaced the dipstick tube with one that doesn't match the stick. The defining mark on the stick must indicate full at a point below the lowest portion of the arc the crankshaft components scribe, whether it be the con-rod bolts or the counterweights to prevent foaming. Finding another motor like yours and doing some measurements would be the best. Hopefully somebody here has one and will help. Purchasing a matched set of tube and dipstick for the serial number of your engine should give you the correct oil level compared to the crankshaft, then it's just a matter of filling her up. Large capacity is good as long as it's not too high.

Good luck and let us know what it took to straighten it out.

 

[DennisG01]

Good thought on a higher capacity pan as a possible explanation, as well.

One thing I noticed... the dipstick looks awful new. The grab handle looks pretty darn good for 34 years old.

 

[jchiotti]

Thanks for the advice. I am going to take some more measurements this weekend and make a plan of attack. I did call a supposedly good Mercruiser mechanic and they said to just find a dipstick that will reach to were the oil now is in the oil pan and run it like that since I put 5 qts in it so that should be right based on engine specs.

I also plugged the serial # of my motor into the Mercruiser site and through some DD found that the part of the dipstick that goes into the tube is supposed to be 25” long. Mine is 24”, however even that one extra inch wouldn’t reach where the oil currently sits in the pan. Would still need to be longer.

So may have an extra capacity oil pan.....not sure how to tell.

Thanks again

 

[seasick]

I would see if I can find someone with the same block who can pull their dipstick and measure the length from the high mark on the stick to the base of the bushing(plug).
Assuming your stick is close to that measurement, I would add oil until it reads full. If you have a different (larger capacity) pan, it would need more oil.