Oil Leak 1998 Sundancer 270SE

[island trek1]

I noticed at the end of last season a small oil leak that seemed to come underneath the motor close to the transom on my 1998 Sea Ray Sundancer. I have a single 260HP Mercruiser engine. Anyone know what the source may be in that location? I thought I might put a mirror under the engine to try to get a better look. I just want to have a good idea what to check for before the Marina tells me I HAVE to have the engine pulled. Anyone have this model and have the same problem? I haven't posted in a while and am impressed with the new look of the board. I also loved the Club Sea Ray Burgee I puchased.

 

[msd58]

Oil leaks are not too difficult to locate on motor. You first need to find out if its motor oil, trim fluid or drive fluid. Are you sure its motor oil? How much oil are we talking about?

 

[sbw1]

You may want to clean things up, put down a diaper and see what happens. There are some small leaks on engines, transmissions and drives that are not worth the expense of fixing. As long as they do no harm, do not require adding fluids (a tranny can weep for years with no noticable effect on the dip stick) all the time, it is sometimes best to simply live with them. Anyone who owned a new GM car from 80's learned to live with a few spots of oil on the garage floor. Not the preferred option, but that was the way it was. This could be the modern day equivilent.

 

[dpvandy01]

I chased a small leak in my 250 for 5 years. Multiple trips to Sea Ray since the engine was new when I bought the boat. Nothing was ever found. I checked the oil weekly and prior to cruising and I never had to add. Through the entire season it never needed to be topped off. I came to the conclusion that even a small amount of oil in the bilge looks like alot more than it actually is.. You can start by checking the oil pan and seals. the only place that I ever noticed any evidence was around the pcv valves but it was never enough to get me worried. good luck..

 

[Salty Dog - LI]

SBW1 is giving you good advise. Clean the bilge and put down an absorbant pad to see where the leak drops down. Auto parts places sell inspection mirror on extension rods (I have 2 different sizes). Once you locate the drip placement, a drop light under the engine and the inspection mirror should help you locate the source. Engine fluids have various colors (brown- engine oil, red- transmission, clear- power steering). The fluids can also run down from higher leaking sources. Most likely it is engine oil. Engine top leaks are easy to spot. Engine head bolts or manifold bolts can loosen and leak oil through the bolt treads or gaskets. Engine head gaskets and manifold gaskets can crack. If you blow a gasket, the manifold and/or engine head may have to come off (big job if an engine head has to come off for gasket replacement). Oil hose lines can also crack, or hose clamps loosen. An oil leak can also come from a cracked distributor shaft gasket. When I did an upper engine rebuild on my engine due to a stuck lifter (1 day off, 2 days back on), I was real careful putting the engine back together- using sealants on the gaskets where needed, and properly torquing the thread sealant applied engine head and mainifold bolts to manufacturer specs. Result- no oil leaks!

Good luck finding your fluid leak!

 

[island trek1]

Thanks for the replies. It is definately engine oil as It did affect the dip stick and I have had to top off. I already put a soaker pad underneath the engine and located the leak underneath toward the stern. The leak wasn't as bad a I thought coming back from a trip on rough seas, the oil mixed with water that had gotten in the bilge so it seemed bad. I will definately get one of the mirrors and hope it's something loose. Knowing this Salty Dog, what do you think it probably is? Are there bolts or hoses undeneath?

 

[douglee25]

If it's definitely an oil leak, it's probably one or a combination of these four things.

1. Valve cover gaskets. These tend to need replacement every few years. The cork seals dry out and thus the leak starts. You can try tightening up the valve cover bolts and seeing if that helps.

2. Oil pan gasket. Again, try tightening up the oil pan bolts.

3. Rear main seal. Although this could be a possibility, I would suspect a dried valve cover or oil pan gasket first. You will need the engine removed if that is the cause. I would just keep adding oil if the leak isn't too bad.

4. Intake manifold. Where the manifold rests on the block's surface, oil usually can leak on the rear or front sides. Some small blocks use end seals while most people do away with them a lay a bead of RTV down instead.

Doug

 

[island trek1]

Thanks Doug and everyone. Can these 4 things be accomplished without pulling the engine?

 

[douglee25]

Thanks Doug and everyone. Can these 4 things be accomplished without pulling the engine?

You can tighten the valve cover and oil pan bolts without issue. Snug them up but don't torque the crap out of them. You don't want the gasket to be compressed out from the two surfaces. If those gaskets need to be replaced, the valve cover can be done without removing the engine, but the oil pan may need to be looked at to double check clearance. I would lean towards it being possible without removing the engine (just drop down and replace gasket). I'm pretty sure the manifold bolts won't be loose, but if indeed the manifold ends are the source of the leak, the manifold can be pulled without removing the engine.

Doug

 

[bone354]

You most likely have a remote oil filter. Check to see if the hoses or where the hoses connect to adapter assembly.Where the oil filter would go If it was a automobile engine.I had a leak last year from that area.

Rich

 

[rondds]

i had an old boat years ago that had a rusted oil pan (at the bottom). the rust caused a perforation. all the years of salt water (from the bilge) sloshing up finally took it's toll.

 

[island trek1]

Thanks for the replies. I cjeck out all of these suggestions.