Oil and filter change after 20 hour run in period.

[rcon]

I'm new at all this mechanical stuff so I'm after some guidance on proper process for changing oil and filer now that I'm approaching 20 hours on new 4.3l TKS Mercruiser.

The Operation, Maintenance & Warranty Manual is all over the shop, with Bravo, Alpha and engine maintenance schedules, with procedures for them all so I'm after clear guidance on what I'll be following - I'm certain there is someone on here that has done this before.

I gather I'm due for a change out after 20 hours, what do I do?

Does the boat need to be out of the water?


As I understand it, I'd run the engine for 5 minutes,
turn off,
drain oil (sump? remote port hopefully!),
test level,
top up as needed,
change filter,
run,
top up as needed.

 

[northern]

Checking and changing the oil in the legs is a good idea after 20 hours since they are new. If milky you probably need new seals. It needs to be out of the water. If engine oil is milky you have problems. Should change that also.
I change the engine oil after the engines have run for at least an hour after I return from a trip. If you warm them up at the dock the oil never seems as hot as it does after a trip.

 

[rcon]

Thanks, Northern.

Only new engine - they don't come cheap over here :/ Nor are they over there I'm sure, but I recall reading they're about double here.

Good point regarding doing it after coming back from cruise, rather than just a dock warm up.

I gather from your post, changing engine oil can be done at the docks?

I also get the impression from your post that checking for milky drive oil is possible in-water, to do that would I just trim the drives up and use that top access point?

 

[Budman]

I'm new at all this mechanical stuff so I'm after some guidance on proper process for changing oil and filer now that I'm approaching 20 hours on new 4.3l TKS Mercruiser.

The Operation, Maintenance & Warranty Manual is all over the shop, with Bravo, Alpha and engine maintenance schedules, with procedures for them all so I'm after clear guidance on what I'll be following - I'm certain there is someone on here that has done this before.

I gather I'm due for a change out after 20 hours, what do I do?

Does the boat need to be out of the water?


As I understand it, I'd run the engine for 5 minutes,
turn off,
drain oil (sump? remote port hopefully!),
test level,
top up as needed,
change filter,
run,
top up as needed.

Just a little off in the sequence.

Run until oil is warm
Drain oil (sump or suck out through dipstick hole)
Remove old filter, if inverted, you can punch a hole in the top to make sure all oil drains out.
Replace filter - Clean the seating surface. Run a light oil film on the new filter gasket. Screw on the new filter hand tight, then 1/8 turn more.
Replace drain plug if removed
Fill with new oil
Run for 1 - 2 minutes while verifying oil pressure and checking for oil leaks
Check oil level.

 

[northern]

I never thought of checking leg oil in the the water by lifting the keg out of the water. You could probably losen the plug a bit and get a few drops out. When we had a boat with legs they lifted the boat out of the water to change the leg oil. Others on this site with legs probably can better advise you. On changing oil Budman has good points you can suck it out the dip stick if the drain plug is hard to get to. There will be about 1 quart left in the engine when you do this. I used to do it on my 3.8 V6ies and it worked fine. If the filters are in a place you will spill oil when you remove them I used to losen them then put a plastic bag on them and finish screwing them off. Oil will be hot, wear rubber gloves. I use the ones that the you use for doing dishes, they have a bit of insulation in them.

 

[Dave S]

I always change my engine oil with the boat in the water. I use an Oil Boy pump (like the one shown below) which has a hose that screws right on the dipstick. I change the oil when it is warm. The oil filters should be changed as well. As someone else mentioned, if you have an inverted filter it is less messy when you remove them if you first punch a few holes in the top of the filter which allows it to drain back into the engine sump. I strongly recommend you use Mercruiser Oil and a Mercruiser Filter when doing the oil change. This is especially important if the new engines came with Mercruiser warranties.

Did you also change your outdrives when you replaced the engines? If they are new, then the oil should be changed in them as well. Unfortunately the boat needs to be out of the water to do that. If the outdrives are not new, then I recommend changing the oil annually and pulling each drive as well. If they are older drives you will likely have to grease the u-joints and the only way you can do this is by pulling the drives. The spline shaft also needs to be greased. One of the other reasons for pulling the drives annually and changing the oil is too check for any signs of water leaks as well check the condition of the gimbal bearing and the u-joints. If you have older drives, check the condition of all your bellows as well.

Dave