1986 Sea Ray 300 Sundancer Cruiser

B

bsampica

New Member
Jul 28, 2014
29
United States
Boat Info
1992 400 Express Cruiser
Engines
Twin 454 7.4 L Big Blocks - Straight Inboards
Hey Everyone, brand new "member" to the forums here - but I've been reading relentlessly for months, and we've finally settled and purchased a 1986 Sea Ray Sundancer 300 DA. The boat has twin 5.7 Merc's with 260 HP that run great, but I have a couple of questions:

1.) I need to replace the starboard (or possibly both) out drives. I knew this going in to my purchase. They are original and have never been replaced. I'm going to do the gimbal's, boots and other related replacements at the same time while I have the drives off, this is going to be an upper and lower replacement. My question is: What was the original out drive on these boats, it's not an Alpha One I don't think, though it looks like it kinda. The archives lists it as a 1.5 gear ratio with 14x19 prop, do I replace them with the SEI 1.47 ratio as the closest match, what have others done?

2.) I'm having trouble finding concise answers on the tank sizes (fuel, water, waste) on this boat - anyone know for sure what the tank sizes are, and the estimated range on calm waters at cruising speed?

3.) For the life of me, I can't find the waste pump out connection. Obviously the waste screw port by the fresh water filler isn't the pump out location. I assume that's just for flushing the waste system with fresh water while you're pumping it out via the RV style hookup...anyone know where the heck it is?

Pictures to come soon, it's a beautiful boat, in wonderful shape overall. :) Thanks in advance.
 
Waste port should be for the pump out. they suck it out via that port. at the marina.
 
alwhite00 said:
Waste port should be for the pump out. they suck it out via that port. at the marina.
Click to expand...

Then I'm clueless. The waste port near the fresh water filler is a small metal flush fit port that looks like the fuel filler or water filler. The large RV style clasp with the double levers on each side won't fit on this port by any stretch of the imagination.
 
I owned an '86 300 at one time. Mine had Alpha drives, hooked to the 260 Mercs.

Seems to me they had twin 70 gallon fuel tanks…. but don't quote me on that!
 
Boatingnut said:
I owned an '86 300 at one time. Mine had Alpha drives, hooked to the 260 Mercs.

Seems to me they had twin 70 gallon fuel tanks…. but don't quote me on that!
Click to expand...

That hooks up to some of the answers I've gotten. Most have told me that I have 140 gallon fuel capacity, but there's two tanks, so I was trying to figure if it was 140 per tank, or 140 total. 70 / 70 would make sense if that's how you remember it Boatingnut. :) I suppose I'll know as soon as I get the drives replaced and fill the tanks to the top. :)

You said they are Alpha 1's on your boat - have you ever had to replace parts or outdrives on your rig?
 
The fuel tanks are 72 gallons each, 18 gallon waste tank, 40 gallon water tank, 6 gallon water heater.

What is wrong with the outdrives? Why replace them? I believe my 89 had 1.5 ratio drives. If you do replace them, get one counter rotation for better handling at the dock.

The Sea Ray website still has some info for these old boats:

http://www.searay.com/Page.aspx/pageId/10532/Model-Archives.aspx
 
worzy1014 said:
The fuel tanks are 72 gallons each, 18 gallon waste tank, 40 gallon water tank, 6 gallon water heater.

What is wrong with the outdrives? Why replace them? I believe my 89 had 1.5 ratio drives. If you do replace them, get one counter rotation for better handling at the dock.

The Sea Ray website still has some info for these old boats:

http://www.searay.com/Page.aspx/pageId/10532/Model-Archives.aspx
Click to expand...

Thanks! That helps a lot. I actually had ended up on this page:

http://www.searay.com/Page.aspx/pageId/10411/Owners-Manuals.aspx

But when I choose 1986 I don't get the Sundancer options in the next drop down, 85 and 87 have them...

The starboard side outdrive has a stripped out dog clutch and upper gears, it ran metal all the way through the lower unit. I figured while I was replacing 1, I'd replace them both since the gear ratio is different. 1.5 is whats listed on the charts, but I can't find a 1.5 offering. SEI has a 1.47 - and I think I'll go with a counter rotating side as well since I'm going to be replacing both.

I'm just curious what others who have replaced out drives have used - and what kind of gotcha's or lessons you've learned with your choices.
 
I have an SEI counter rotating lower on my port drive and it works great. The other guys have you dialed in on the tank sizes and the waste port is the small round 'gas fill' looking one on the port side.
 
You can download stuff from Sea Ray. Doesn't matter if it's for 86 or 87, they are the same anyway.
If replacing both drives, then go for the counter rotating on the port side. Makes a big difference around the dock.
Sea Ray put 14X19 aluminum props on these boats when new. Mine had them when I got it and it was a dog. Changed to 15.5X17 stainless and the boat really gets up on plane nicely and flies with them.
 
worzy1014 said:
The fuel tanks are 72 gallons each, 18 gallon waste tank, 40 gallon water tank, 6 gallon water heater.

What is wrong with the outdrives? Why replace them? I believe my 89 had 1.5 ratio drives. If you do replace them, get one counter rotation for better handling at the dock.

The Sea Ray website still has some info for these old boats:

http://www.searay.com/Page.aspx/pageId/10532/Model-Archives.aspx
Click to expand...

Spec sheet for the OP's '86: http://www.searay.com/boat_graphics/electronic_brochure/company1729/1C1_27_74DERNJW4481.pdf

I have an '89 and haven't found direct reference to size of waste tank....are they really as big as 18 gal on boats this size? I was thinking more like 10 and have been pumping out like a fiend!
 
Last edited:
Thanks for all the great advice everyone. Looks like the SEI replacements at 1.47 ratio is the way to go to replace the original equipment at a 1.5 ratio. I'll have to mess around with props a little bit. I don't quite understand the suggestion above to run with a 15.5x17 prop over a 14x19. It seems to me that prop would reduce your top speed somewhat, though it would kick you onto plane faster, or do I have it backwards? What is your WOT RPM and your Cruising RPM's with that prop?
 
bsampica said:
Thanks for all the great advice everyone. Looks like the SEI replacements at 1.47 ratio is the way to go to replace the original equipment at a 1.5 ratio. I'll have to mess around with props a little bit. I don't quite understand the suggestion above to run with a 15.5x17 prop over a 14x19. It seems to me that prop would reduce your top speed somewhat, though it would kick you onto plane faster, or do I have it backwards? What is your WOT RPM and your Cruising RPM's with that prop?
Click to expand...

I cruise at about 3100-3200 RPM (just before secondary's open up) doing anywhere between 27-30 MPH on GPS depending on conditions and load on the boat. I don't have a genny or arch.
I pushed it to WOT in dead calm water shortly after I re-powered to see what the properly broken in motors could do. It was shortly after sunrise, no water in fresh or waste tanks, probably 1/4 gas, and only my daughter who weighs around 115 pounds, and me at 175 aboard. I got it up to 4600 RPM and hit 50 MPH on the GPS momentarily before I lost my nerve (new motors) and backed it off.
This boat is plenty fast enough for me.
IMHO: The aluminum props that Sea Ray put on the boat slip (or flex) too much under the weight and beam of this relatively heavy/wide boat. Much less slippage with the stainless props.
The pitch gets me up on plane a lot faster. The larger diameter moves more water.
Been running these props for 5 or so seasons and love them.
The prop change was the best thing I've done for the boat in the 8 years I've owned it. Tied for second best were the re-power and the counter-rotating prop on the port side. The motors speak for themselves, but the CR drive makes the boat a lot more user friendly around the dock. I highly recommend that if you are changing a drive (or drives anyway).
I also added half system fresh water cooling and remote oil filters to the new motors. The oil filters are a pleasure and another mod I highly recommend. The filters are right up against the stringers (especially the starboard motor) in the stock location. Very hard to maneuver out of there without spilling a little in the bilge (at least for me), even with the oil absorb pads under them I still had a mess to deal with after oil changes.
 
JVM225 said:
I cruise at about 3100-3200 RPM (just before secondary's open up) doing anywhere between 27-30 MPH on GPS depending on conditions and load on the boat. I don't have a genny or arch.
I pushed it to WOT in dead calm water shortly after I re-powered to see what the properly broken in motors could do. It was shortly after sunrise, no water in fresh or waste tanks, probably 1/4 gas, and only my daughter who weighs around 115 pounds, and me at 175 aboard. I got it up to 4600 RPM and hit 50 MPH on the GPS momentarily before I lost my nerve (new motors) and backed it off.
This boat is plenty fast enough for me.
IMHO: The aluminum props that Sea Ray put on the boat slip (or flex) too much under the weight and beam of this relatively heavy/wide boat. Much less slippage with the stainless props.
The pitch gets me up on plane a lot faster. The larger diameter moves more water.
Been running these props for 5 or so seasons and love them.
The prop change was the best thing I've done for the boat in the 8 years I've owned it. Tied for second best were the re-power and the counter-rotating prop on the port side. The motors speak for themselves, but the CR drive makes the boat a lot more user friendly around the dock. I highly recommend that if you are changing a drive (or drives anyway).
I also added half system fresh water cooling and remote oil filters to the new motors. The oil filters are a pleasure and another mod I highly recommend. The filters are right up against the stringers (especially the starboard motor) in the stock location. Very hard to maneuver out of there without spilling a little in the bilge (at least for me), even with the oil absorb pads under them I still had a mess to deal with after oil changes.
Click to expand...

Thanks for the explanation - you are correct, it's a big heavy boat, and I absolutely intended on going with the CR port side drive and regular rotation starboard drive, it's really not to bad right now, my lake is pretty calm most days, and the harbor my slip is in is almost always calm, but I can feel the drift, and if wind or current were added to that I'd be in trouble, so having the CR drive on there should help. I typically run with a more full water tank, a few more people on the boat and I do have a geny and arch on mine, would you still recommend the prop changes?

What brand filter extender did you add-on with? I've had trouble in the past with these developing slow drips or leaks that I usually try to stay away from adding to oil or cooling systems, but if you've found a brand you're happy with, that sounds like a great upgrade.
 
The CR drive on the port side is a great investment! You won't notice anything going forward, but backing up, or crabbing over around a dock will be much easier.
I would absolutely recommend the prop swap based on my experience and your boat being much heavier with the arch and genny. I called PropMD (do a google search for them), and they recommended the stainless props I have, sold them to me, and had a great price.
I used Mercruiser brand remote filter kits and have no issues with them so far. They cost a little more than the other stuff out there, but I was already going for two brand new motors complete from flame arrestor to pan, with complete new ignition etc., new manifolds, risers, and half system fresh water cooling, so the extra few bucks didn't matter at that point.
It was a big financial commitment to the boat at the time, but when I factored in how much I really love this particular boat, and what it would cost to replace it with something of similar size, it was a no brainer for me. I could not have gone out and bought another 30' boat with new power for anything near what it cost me.
 
Last edited:
I removed all the waste-treatment, miniature holding tank before you pump it out in the drink system. Closed off the through hull hose, installed 20 gallon holding tank. Muchhhhh better. Have a state inspection of facilities, coming up next week. Should be all good.
Let me know if anyone needs pics or details. O'yeah! I have a Diesel Genny down there too!
 
You must log in or register to reply here.

Forum statistics

Threads
113,170
Messages
1,427,742
Members
61,079
Latest member
capeharj
Back
Top