Mercruiser Oil Change
 

I have a new to me '81 Mercruiser 228 5.0L. The dipstick tube has a
threaded fitting for a hose attachement that, I think, is there to suck
the oil out. I don't know if there is a plug on the oil pan or not.
I'd either have to remove my whole rear seat (possibly openning a huge
can of worms) or stand on my head in the engine compartment to find
out.

I know that they make hand pumps to get the oil out but I want to do is
hook up a hose to the dip stick tube with the other end lower than the
engine (in a bucket on the ground). Instead of needing a pump or
sucking on the hose to get a siphon started, I was wondering if I might
be able to apply a VERY SMALL amount of air pressure to the crankcase
to get it started. I'd do this probably through the PCV fitting. When
I say VERY SMALL, I mean like 2 or 3 psi. Just enough to get the flow
started. I would increase the pressure in very small doses if 2 or 3
was too little. A dumbass would apply 40 psi and blow out a seal or
gasket. I may be dumb but not that dumb. Can anybody tell me if this
will work or if there are any problems with it?

Chris

It's too thick to siphon. Get the pump.

wrote in message
oups.com...
I have a new to me '81 Mercruiser 228 5.0L. The dipstick tube has a
threaded fitting for a hose attachement that, I think, is there to suck
the oil out. I don't know if there is a plug on the oil pan or not.
I'd either have to remove my whole rear seat (possibly openning a huge
can of worms) or stand on my head in the engine compartment to find
out.

I know that they make hand pumps to get the oil out but I want to do is
hook up a hose to the dip stick tube with the other end lower than the
engine (in a bucket on the ground). Instead of needing a pump or
sucking on the hose to get a siphon started, I was wondering if I might
be able to apply a VERY SMALL amount of air pressure to the crankcase
to get it started. I'd do this probably through the PCV fitting. When
I say VERY SMALL, I mean like 2 or 3 psi. Just enough to get the flow
started. I would increase the pressure in very small doses if 2 or 3
was too little. A dumbass would apply 40 psi and blow out a seal or
gasket. I may be dumb but not that dumb. Can anybody tell me if this
will work or if there are any problems with it?

Chris

With my old new to me beater, I went to the trouble of finding the drain
plug (picked up the appropriate Seloc manual first) . I found that I can fit
a pan in there and drain the oil that way. I am more comfortable knowing
that the oil ... and any crud left by the previous owner(s) ... was/is
draining from the bottom of the pan rather than from who knows where using a
pump. And ... by removing the seat and so on, I got a good look at the lower
part of the engine ... oil cooler, hoses and so on ... to verify all was
well. And if you trailer the boat or take it out of the water now and then,
there is a replacement for the drain plug comprising a fitting and hose that
lets you drain the oil through the hull drain plug.

I don't know if there is a plug on the oil pan or not.
I'd either have to remove my whole rear seat (possibly openning a huge
can of worms) or stand on my head in the engine compartment to find
out.

Even if the oil is hot? Most sources I've seen recommend changing the
boat oil when warm when doing through the dipstick tube. The reasons
are to ease flow and to get any particles and polutants in suspension.
If it won't siphon, I could keep the air pressure on the PVC port and
push it out. Right?

Chris

If you have a lot of patience the air pressure might get it out. I would
try to figure a way the you can keep it hooked up from a while. Still does
not seem to be worth the trouble just to avoid buying a 25$ hand oil pump.

I installed one of the drain hoses in place of the oil pan plug. I push it
out the drain hole in the back of the boat and then just let it run out.
But youy do need to be able to reach the bottom of the engine to do that and
on some boats you can't.

wrote in message
ups.com...
Even if the oil is hot? Most sources I've seen recommend changing the
boat oil when warm when doing through the dipstick tube. The reasons
are to ease flow and to get any particles and polutants in suspension.
If it won't siphon, I could keep the air pressure on the PVC port and
push it out. Right?

Chris

On 6 May 2005 14:18:00 -0700, wrote:

I have a new to me '81 Mercruiser 228 5.0L. The dipstick tube has a
threaded fitting for a hose attachement that, I think, is there to suck
the oil out. I don't know if there is a plug on the oil pan or not.
I'd either have to remove my whole rear seat (possibly openning a huge
can of worms) or stand on my head in the engine compartment to find
out.

I know that they make hand pumps to get the oil out but I want to do is
hook up a hose to the dip stick tube with the other end lower than the
engine (in a bucket on the ground). Instead of needing a pump or
sucking on the hose to get a siphon started, I was wondering if I might
be able to apply a VERY SMALL amount of air pressure to the crankcase
to get it started. I'd do this probably through the PCV fitting. When
I say VERY SMALL, I mean like 2 or 3 psi. Just enough to get the flow
started. I would increase the pressure in very small doses if 2 or 3
was too little. A dumbass would apply 40 psi and blow out a seal or
gasket. I may be dumb but not that dumb. Can anybody tell me if this
will work or if there are any problems with it?

Chris

I just did mine for the first time last week. I used a little cheapo
pump that you hook to a drill. I think it cost $5 or so from Harbor
Freight, but I just had it laying around in the garage. I had to add
the hose and fittings which are just standard garden hose parts. Total
outlay (including the original cost of the pump) might have reached
$10 to $12. It only took a few minutes to pump out. I would simply buy
a pump and do it as designed.

The Other Dave Hall

On 6 May 2005 14:18:00 -0700, wrote:

I have a new to me '81 Mercruiser 228 5.0L. The dipstick tube has a
threaded fitting for a hose attachement that, I think, is there to suck
the oil out. I don't know if there is a plug on the oil pan or not.
I'd either have to remove my whole rear seat (possibly openning a huge
can of worms) or stand on my head in the engine compartment to find
out.

I know that they make hand pumps to get the oil out but I want to do is
hook up a hose to the dip stick tube with the other end lower than the
engine (in a bucket on the ground). Instead of needing a pump or
sucking on the hose to get a siphon started, I was wondering if I might
be able to apply a VERY SMALL amount of air pressure to the crankcase
to get it started. I'd do this probably through the PCV fitting. When
I say VERY SMALL, I mean like 2 or 3 psi. Just enough to get the flow
started. I would increase the pressure in very small doses if 2 or 3
was too little. A dumbass would apply 40 psi and blow out a seal or
gasket. I may be dumb but not that dumb. Can anybody tell me if this
will work or if there are any problems with it?

Chris

Drill a hole in the bottom of the boat, and make a little door. That
way, you can easily change your oil.

Update:

I went ahead and removed the rear seat so I could get to the drain
plug and oil filter. With the seat removed (which wasn't hard to do)
there was actually alot of room between the bottom of the oil pan and
the hull. A regular oil pan didn't fit because of the V-shape of the
space but an old stainless steel dog dish fit perfectly with plenty of
room left for my arm and a crescent wrench. I laid on my back on the
floor perpendicular to the centerline of the boat. In that position, I
could easily reach out with my right arm and get the the drain plug. I
could reach the oil filter well enough but someone with shorter arms
than me might have a problem (I'm 6'1"). I pretty much had to get my
shoulder right up against the crankshaft pulley to reach it. The dish
wasn't big enough to hold 5 quarts so once the dish filled up, I put
the plug back in finger tight and them came back for the rest after
emptying the dish. A 1 gallon milk jub with the top cut off probably
would have worked just as well.

So what I have learned, at least on this boat, is not to screw around
with suction pumps or trying to "blow out" the oil. It's easy enough
to do it the old fashioned way.

Chris

On 25 May 2005 08:49:53 -0700, wrote:

Update:

I went ahead and removed the rear seat so I could get to the drain
plug and oil filter. With the seat removed (which wasn't hard to do)
there was actually alot of room between the bottom of the oil pan and
the hull. A regular oil pan didn't fit because of the V-shape of the
space but an old stainless steel dog dish fit perfectly with plenty of
room left for my arm and a crescent wrench. I laid on my back on the
floor perpendicular to the centerline of the boat. In that position, I
could easily reach out with my right arm and get the the drain plug. I
could reach the oil filter well enough but someone with shorter arms
than me might have a problem (I'm 6'1"). I pretty much had to get my
shoulder right up against the crankshaft pulley to reach it. The dish
wasn't big enough to hold 5 quarts so once the dish filled up, I put
the plug back in finger tight and them came back for the rest after
emptying the dish. A 1 gallon milk jub with the top cut off probably
would have worked just as well.

So what I have learned, at least on this boat, is not to screw around
with suction pumps or trying to "blow out" the oil. It's easy enough
to do it the old fashioned way.

Chris

Cool! Wish I could get to my drain plug as easily.

--
John H
On the 'PocoLoco' out of Deale, MD

"Divide each difficulty into as many parts as is feasible and necessary to resolve it."
Rene Descartes (A true binary thinker!)

wrote in message
oups.com...
Update:

I went ahead and removed the rear seat so I could get to the drain
plug and oil filter. With the seat removed (which wasn't hard to do)
there was actually alot of room between the bottom of the oil pan and
the hull. A regular oil pan didn't fit because of the V-shape of the
space but an old stainless steel dog dish fit perfectly with plenty of
room left for my arm and a crescent wrench. I laid on my back on the
floor perpendicular to the centerline of the boat. In that position, I
could easily reach out with my right arm and get the the drain plug. I
could reach the oil filter well enough but someone with shorter arms
than me might have a problem (I'm 6'1"). I pretty much had to get my
shoulder right up against the crankshaft pulley to reach it. The dish
wasn't big enough to hold 5 quarts so once the dish filled up, I put
the plug back in finger tight and them came back for the rest after
emptying the dish. A 1 gallon milk jub with the top cut off probably
would have worked just as well.

So what I have learned, at least on this boat, is not to screw around
with suction pumps or trying to "blow out" the oil. It's easy enough
to do it the old fashioned way.

Chris

Chris,

You might want to consider replacing your plug with a valve like this one:
http://www.fumotovalve.com/

I've put these on all my (inboard) engines, and they work great. The ones
that I use have a nipple on them, so I can connect a hose to it, and run it
thru one of the hull drain holes.

I also new a guy who put an electro-magnetic valve on his oil drain, but
that seems a bit over the hill, and risky as well.

Good luck, and happy boating.

--
-Netsock

"It's just about going fast...that's all..."
http://home.columbus.rr.com/ckg/