Engine Oil Leak

[conradg]

I have an American Skier Pro 2001 with Marine Power Engine. I was getting it ready for Summer (Southern Hemisphere here!) and noticed oil dumped on the ground under the boat. On investigation, I discovered it was coming from the bottom of the oil pan. Its extremely difficult to see whats going under there but I concluded that it was the fitting for the oil drain pipe that screws into the bottom of the pan. I removed the fitting and noticed some pieces of material in the threads. Not metal but something else. Also the pan looks a bit bulged under the paintwork around where the fitting was. I have been using the boat in salt water and I think the pan is often sitting in salt water that sometimes accumulates in the bilge.

I think I may have to pull the engine to fix this but interested in any feedback or suggestions before I do this. 

Thanks in advance.

[conradg]

Typo, thats an American Skier 2002.

[backfoot100]

If the boat is being used in saltwater I would suspect you have rust issues. The pan is steel and the bulging you see by the drain fitting is most assuredly rust bubbling up the paint. I'm guessing the other material you see on the threads is a pipe sealant of some sort and nothing to worry about.
If that is truly the case, the only way to fix it is to pull the engine. I would assume that the pan needs to be replaced. If it isn't rusted too bad you might be able to repair but seeing as it's being used in salt, I would just replace it.
 
Ron and/or Dan may have some other options for you and they are better suited to respond in this instance than I am.

As a side note, I think the Marine Power engines all had aluminum exhaust manifolds. At least the ones I've seen, but that certainly isn't many and I could definitely be wrong on that. If you're pulling the engine, I would highly suggest that you remove and check over the exhaust manifolds and risers to make sure that they are sound. Saltwater takes its toll on cast iron manifolds and they usually only last about 5 years. Aluminum and saltwater would have to be even worse. If your oil pan has been rusted into this condition I wouldn't be surprised if the manifolds and/or risers also need replacing. No matter if they're cast iron or aluminum. Just fair warning.

[conradg]

Thanks for the advice. My engine does have aluminum manifolds.

[RonT]

As always Backfoot is right on, in addition to what he said you will want to verify that you have enough clearance between the oil pan and the turn fin bolts, you need 3/4".  When these boats run in rough water the bottom will flex and cause the bolts to "tap" the oil pan causing leaks as well. You will need to replace or repair the pan.
In addition I would at least run a fresh water flush to flush the salt out after every use, or add a fresh water cooling system (heat exchanger) 

[conradg]

Ok, I am going to check clearance under the sump and pull the engine to fix the hole in the sump. Considering that I will continue using the boat in salt water, any suggestions for the sump? Should I just get it fixed and repainted or replace it with the same or some other version?

I think I need to keep the water out of the bilge as I notice the starter motor and bottom of bell housing are taking some rust damage. I had issues in the past with a Mercruiser where the guard on the engine side of the bell housing at the bottom was missing and water was being sprayed by the flywheel into the starter motor which resulted in many replacements of the bendix until I made a guard plate and installed it.

[conradg]

One other question? How much does the Marine Power engine with the transmission weigh? Just want to make sure I don't pull my garage roof down in the process of pulling the engine.

[backfoot100]

I checked the Indmar engine specs that I have for my model year ('86). I also have aluminum exhaust manifolds like you. The only difference is you have EFI but overall, it should be still be somewhat similar in weight.

My 300SP (350CI) is listed at 700 lbs. The standard 275HP 350 CI engine is listed at 830 lbs.
I know that I weighed my manifolds when I rebuilt my engine and they were 17 lbs. each. I know that cast iron manifolds are heavy but I just can't believe that each one would weigh 65 lbs. more than the aluminum ones so I would have to questions those numbers. Maybe if the 300SP had an aluminum intake in addition to the manifolds, the weight difference would be justified but it didn't so take it for what it's worth.
The tranny is easily another 100 lbs. if you remove it with the engine.

As for the pan, I would replace it. You may be able to repair, but I would guess a repair is not going to last as long as a new one.

My own personal opinion is you'll not be able to keep the bilge dry. Putting in a PSI shaft seal would help (or something similar) but isn't a guarantee either. These boats are designed to have some water drainage into the bilge so you won't be able to completely prevent it. The best option is a thorough freshwater flush after each outing.

As a side note, my Indmar documentation specifically states that any engine options that include aluminum manifolds are not recommended for saltwater applications.

[conradg]

Any suggestions on where to buy a new oil pan from?

I have a 2002 Marine Power 5.7l / 350CID.

Could I use a car replacement oil pan?

[conradg]

Ok I pulled the engine and discovered the bottom of the oil sump is badly rusted (see photo).

Any suggestions on where I can get a replacement oil sump? Can I use a car oil sump? I know it won't have the oil drain pipe but I have just dumped into the bilge in the past on another boat with a big cleanup afterward.

The manifolds don't look too bad but I can see that the salt water is slowly doing its thing to dissolve my engine!

[RonT]

That is a 6 quart pan and runs around $250 plus Shipping. Will get exact cost if needed.

[RonT]

The 6 qt. Plastisol coated Marine pan is $239.95 plus Shipping

[backfoot100]

The manifolds don't look too bad but I can see that the salt water is slowly doing its thing to dissolve my engine!

Don't look too bad. Seriously?? You and I have very differing ideas about what is or isn't too bad. Those are horrid and the only saving grace is that I can't see any leakage between the riser and the manifold. If they start to leak in any way, water can find it's way into the cylinders. Depending on the severity of the leak when it happens (and it WILL happen) the engine can hydrolock and you'll end up with bent valves, bent rods, blown pistons, blown head gaskets or anything else that you can think of when one or more cylinders fills up with water. It can get ugly really, really quick.
I don't know how long it's been running in salt but if it was mine, I would replace them. Salt water requires extra preventative maintenance and this is one of the costs of operation. It's a lot cheaper than waiting until it's too late. I would also replace them with cast iron. They should last longer and would be considerably cheaper.

I hate to be Debbie Downer but I've seen way too many times what happens when manifolds let go on fresh water engines because guys don't heed the warning signs of a leaking riser gasket or an overheat condition left unchecked. Knowing and understanding the consequences of normal salt water operation can prevent these same failures.

Good luck and happy boating.

[conradg]

I hear you backfoot100 and I am investigating options around replacing the manifolds and adding a closed water cooling system. Just compiling a Business Case to submit to the boss for approval!!!! The effects of saltwater don't seem to be as high on her priority list as they are on mine.

I have fixed my sump oil leak am posting the results of the job in case it helps anyone else.

1. I sourced a sump and gasket from my local boat shop. The owner has been in the industry for many years and he knew exactly what I was after. According to him, all the GM 5.7L Evoc based engines have the same core engine block components which include the oil sump. So, he says the same sump is used on Marine Power, Indmar etc. He said it was bad idea to use an old gasket which I knew already from this forum. He indicated that they replace about 15 to 20 sumps a year. Saltwater locations are a lot more accessible here, so maybe that is a factor in this.
2. I pulled the sump off and discovered that the leak was not a hole in the sump, although it was rusted at the bottom, but it  was a stripped oil drain plug thread. I think this must have been damaged at some stage and someone tried to fix it with some kind of sealant. This explains the plastic pieces that I saw when removing the oil drain hose.
3. As suggested by the boat shop guy, I sprayed the pan with a galvanizing/zinc paint and installed it using the Marine Power Service Manual instructions on their website.
4. Re-installed the engine. Went through Ron's shaft alignment instructions and discovered all good. Checked for 2 fingers under the pan. All good. I ran the engine and was relieved to see no oil leaks.
5. When I had the engine out, I removed the starter motor. The business end was looking really bad. Rusted shaft and Bendix. The flywheel and teeth were also looking seriously rusted. On a previous Mastercraft I owned with a Mercruiser engine, I had endless trouble with the starter motor, as on that engine, the starter motor was mounted on top from the back, so water picked up by the fly wheel would be sprayed into the front of the starter motor and due to the angle of the engine would flow out through the back of the starter motor. This would result in regular electrics and Bendix replacements. I ended up pulling the engine on that boat and sealing up the dust cover on the bottom of the bell housing to stop water from getting to the flywheel. I had no further starter motor problems after that. The starter motor on my current boat comes in from the front and hence points down so not as bad as the Mercruiser but still getting abused.
6. Based on the above, to save the starter motor, I sealed up the bottom of the dust cover and after putting the engine back, poured just enough oil into the bell housing so that the teeth on the flywheel just touch the oil. My thinking is that this will keep the teeth lubricated and provide just a little bit of lubrication to the Bendix end of the starter motor. Let me know if anyone sees any issues with this solution.
7. I sorted the Auto Bilge so that it works now! Trying to limit the amount of water in the bilge!
8. Ready to ski! Just need to fix my back and knee problems. I wish it was as easy as the boat.

I would like to say a big thanks to RonT and backfoot100 for sharing their valuable experience on this forum. It has been invaluable over the time that I have owned this boat and I know I will always get the correct/real information I need.

Its 100deg F here today, so Summer has definitely arrived and boat is fixed just in time.

[conradg]

Ok just figured why no one has ever put oil in the Bell Housing: Its a quick way to spread oil all over your boat!

I'll just have to live with it until the oil behind the dust cover runs out.