Any Mercruiser guys out here?

Motley Doo · Aug 18, 2008

We just became the proud owners of a 1986 Chris Craft Scorpion 210 with a mercruiser 5.7/260 hp I/O. This will sound stupid to anyone who hasn't seen this, but HOW IN THE HE!! do you reach the drain plug to change the oil!!!!!! I sure hope I'm not the only one who has issues with this, any anvice would be greatly appreciated!

hilinerider · Aug 18, 2008

on the big inboards i have always just sucked the oil out with a pump and replaced the filter

Jeff C · Aug 18, 2008

Motley Doo said:
We just became the proud owners of a 1986 Chris Craft Scorpion 210 with a mercruiser 5.7/260 hp I/O. This will sound stupid to anyone who hasn't seen this, but HOW IN THE HE!! do you reach the drain plug to change the oil!!!!!! I sure hope I'm not the only one who has issues with this, any anvice would be greatly appreciated!

I feel your pain!

I had a Mercruiser 454 and had to practically do a head stand to get to the drain plug. Actually it was not even a plug. It was a slotted valve that you turned to one side and there was a drain tube attached that I had to work back to the boat rear drain out of the hull. I would just get an "oil boy" vacuum tank, get the oil up to temp and suck it out of the dipstick tube and then change the filter. I was able to get out about 90% of the old oil.

Spend $20 on an oil boy and forget that drain plug!

Ridgerat · Aug 18, 2008

Jeff C said:
I feel your pain!

I had a Mercruiser 454 and had to practically do a head stand to get to the drain plug. Actually it was not even a plug. It was a slotted valve that you turned to one side and there was a drain tube attached that I had to work back to the boat rear drain out of the hull. I would just get an "oil boy" vacuum tank, get the oil up to temp and suck it out of the dipstick tube and then change the filter. I was able to get out about 90% of the old oil.

Spend $20 on an oil boy and forget that drain plug!

2nd that! Mercrusier even makes a little pump that threads right onto the top of your dipstick tube. You can suck the oil out pretty quick.

Reeb · Aug 18, 2008

Ridgerat said:
2nd that! Mercrusier even makes a little pump that threads right onto the top of your dipstick tube. You can suck the oil out pretty quick.

Exactly, my dad used to have me climb upside down in the engine bay changing oil all the time until I saw how we was winterizing boats. He just smiled and kept muttering, "Age and treachery" guess his dad did it to him when he was my age. From then on it was way too easy to change oil.

Motley Doo · Aug 18, 2008

Alright, thanks guys, will be making a trip to the boat dealer for an "Oil Boy". You guys just saved me hours of blood, sweat, and tears. Thanks all!

oonighttrain · Aug 18, 2008

you guys are all wrong!!! all you need to do is take a hole saw to th ebottom of the hull.. then use an extension and a socket.. whalla.. simple as that!!!

Motley Doo · Aug 18, 2008

oonighttrain said:
you guys are all wrong!!! all you need to do is take a hole saw to th ebottom of the hull.. then use an extension and a socket.. whalla.. simple as that!!!

Ufta, we ALREADY have a leak, somewhere, looked over everything, can't find it! We'll drain about 50 gallons of water out of the bottom after 3 hours! Our main bilge pump doesn't work, so we keep the backup handy. Anyone know of a leaky area on those I/O units? Just had the local marine shop put a new lower unit in after the old one froze and cracked (before we had it). But there is still a leak!

94fordguy · Aug 18, 2008

I just bought an older boat with a mercruiser aswell, and was trying to figure it out too... luckily, the oil was changed right b4 I bought it

hehe

I like the drain it through the plug idea tho:beer;

SnowAddiction2 · Aug 18, 2008

Motley Doo said:
Ufta, we ALREADY have a leak, somewhere, looked over everything, can't find it! We'll drain about 50 gallons of water out of the bottom after 3 hours! Our main bilge pump doesn't work, so we keep the backup handy. Anyone know of a leaky area on those I/O units? Just had the local marine shop put a new lower unit in after the old one froze and cracked (before we had it). But there is still a leak!

Umm, I hate to tell you, but more than likely, you have transom rot and your transom assembly is probably leaking at the seal to the back of the boat. Very common problem for old boats with wood reinforced transoms. When the plywood reinforcement is rotten, your transom assy can no longer seal against the transom. Some people will tell you that your bellows went bad, but don't bet on it. if your bellows goes bad, your gimbal bearing, u-joints and shaft go bad in a hurry.

I know this from experience. I spent 5 months last year replacing extensive dry rot in my 22' mirage. Easiest way to check is to take a 1" hole saw and cut into the inside of the transom (do not cut into the outer fiberglass skin though). Inspect the wood plug you take out. I bet you 10 to 1 odds you will find mush.

If you do have transom rot, DO NOT ignore it. This is a recipe for disaster. Your transom assy could come slightly dislodged, and your boat will sink fast.

snownman · Aug 19, 2008

water leak

another common leak area on a merc. is the shift cable boot, it wont be a massive leak but a consistent trickle when in the water.

Sambo11 · Aug 19, 2008

Did you say 50 gallons in 3 hours? That's quite a bit. I would be concerned about a leak that size.

brushwolf · Aug 19, 2008

Look at the transom plug first(especially if soneone put in one of those nifty little sef draining thingies that seem to fail regularily. next, i would look at the exhaust bellows and the drive shaft bellows. There is also a shift cable bellows. The next thing is the water intake hose that supplys cooling water to the motor. You could also be leaking on a coolant line, an exhaust manifold or even a frost plug in the motor. I would pump out the bilge and dry it with a towel first and then have someone run the thinmg while you are observing for leaks. If it is difficult to see where it is coming from it may help to sprinkle powdered coolaid in the bilge when it is dry and look to see where it starts to color first(kinda like the old cardboard under the car to locate where the leak is trick)...... Hope this helps &Good luck!!!!

SnowAddiction2 · Aug 19, 2008

Also, one thing to check. If your transom is rotted, it will trickle in a small amount of water past the transom assy that will build up salt (if used in salt water). This salt build up will contact the y-pipe and corrode it. The y-pipe will then leak large amounts of water into the bilge. This is how the large amounts of water got into my boat. But the root cause was the rotten transom not sealing properly and allowing trace amounts of water/salt to build up in the transom cutout, thus corroding the y-pipe.

I like the coolaide idea. Thanks. I will put that in my tool belt

Weekday Warrior · Aug 19, 2008

50 gallons in three hours!!! holy crap lol

Is the drain plug in??

I would check the manifold plugs (each side), are they still removed from winter storage?

How about the drain plug in the block? for a V8 there might be 2 of them?? My 4 banger has only one.

Do you have fresh water cooling? Or closed system?

Hope its not the dry rot transom and seal like SnowAddiction2 says, but that could be worst case.

Motley Doo · Aug 19, 2008

Ok, we did find a tear in the big rubber boot, but called the boat shop (who missed it when they had the lower unit off!) and said to replace it, it would cost around $400, so we used a tire patch that is holding fine. We just had the boat out, and this time we are taking on about half as much. When it comes out the bottom of the boat, it's warm, making me think its getting pumped out of a waterjacket or hose somewhere on the motor, but not possitive. No, I haven't checked for rot, will do next time I'm at the shop. And it is just a good old thread-in plug, not a valve. Thanks guys for the help, it's kinda getting frustrating!

xrated · Aug 19, 2008

oonighttrain said:
you guys are all wrong!!! all you need to do is take a hole saw to th ebottom of the hull.. then use an extension and a socket.. whalla.. simple as that!!!

I'd listen to him...he's from Florida they got lots of water and boats.

maxdlx · Aug 19, 2008

So one more ? for the boat Gods. I have the V-6 205 hp merc, and the starter seems to have decided it is done. It looks like I need a gymnist to stand on there head to even see it. Do I takle it myself, or take it to the shop. Looks like pulling the motor would be easier than changing the starter. LOL Maxdlx

SnowAddiction2 · Aug 19, 2008

maxdlx said:
So one more ? for the boat Gods. I have the V-6 205 hp merc, and the starter seems to have decided it is done. It looks like I need a gymnist to stand on there head to even see it. Do I takle it myself, or take it to the shop. Looks like pulling the motor would be easier than changing the starter. LOL Maxdlx

If you take off the exhaust manifold on the side of the starter, you will alot more room for access. Check to see if it would give you enough room to work. Beats pulling the motor, just to change a starter. The starter will have 2 big bolts holding it to the block and a support bracket on the back of the starter. Easy removal and replacement do it yourself job. Keep track of where the wires attach. Make sure you buy a marine starter (explosion proof). After you remove the bolts, you may have to slide the starter under the motor and remove out of the engine well were you have adequate room.

If you do remove the exhaust manifold, it is an excellent time to inspect it for corrosion inside the water passages. If run in salt water, significant corrosion can occure in the riser which is visible by the water passages closing up. It is recommend that the risers get replaced every 5 years or so. you do not want the riser to corrode through the inner wall. A guarentee engine rebuild if this ever happens.

Jeff C · Aug 19, 2008

Doo:

To try and find the rest of the leak, you can rule out the hull.........

Get the boat on the trailer and carefully take a garden hose and fill the bilge all the way to the top, being careful not to get anything electrical (I.E starter motor).

Look under the hull and see if water seeps out anywhere. The water in the bilge will not be under as much pressure as the pressure on the hull from the water on the outside when it is i the water, so a small leak coming out on the trailer, will be a much larger faster leak when in water.

Once you eliminate that, it then has to be one of the bellows, or you are pumping water into the hull when the motor is running. This means frost plugs, fresh water collant lines, or water pump leakage.

How accessable is the bilge for you to get down there and lay down? If you can get down there, get someone to start the boat when in the water, and check for drips/leaks.

Aren't boats fun?

Two happiest dys as a boat owner is the day you buy it, and the day you sell it........

Any Mercruiser guys out here?

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