86 Searay Sundancer 270. What WOT top speed?

[kencat]

Looking at this boat to purchase today, and was out for a sea trial, but was concerned with the engine performance. The engine is a 454 Mercruiser (330) mated to a velvet drive and a TRS outdrive. Approx 1000 hrs on drive train. Boat is in fresh water (Lake Ontario) so bottom should be good. Both gas tanks at 1/4 level, no water stored, 2 180lb men on board. Canvas was down.

I don't know the prop, could not see any stampings under the water, but it was in excellent condition. The outdrive is also in excellent condition visibly, no damage. All the fluid levels good (we checked before the trial).

Getting out of the hole at full throttle the revs would peak at 4000 and climb to max about 4400 - 4500 as speed picked up and tabs trimmed up as well as outdrive. Max speed indicated on the speedo (no gps - dang it!) was about 33mph. The motor sounded like it was not hitting on all cyls, or laboured. I have not heard a 454 before as a reference, but it just didn't sound right to me.

Anyway, I would appreciate any comments, suggestions or hopefully someone has the same boat who can tell me what this boat should be doing if in top shape. It was a beautiful riding boat and handled nicely. Overall excellent shape too, and looks good.

I talked to the owner about getting compression test done so we'll be working on that.

 

[Bondo]

Re: 86 Searay Sundancer 270. What WOT top speed?

climb to max about 4400 - 4500

Ayuh,... I believe that's well within spec...

 

[kencat]

Re: 86 Searay Sundancer 270. What WOT top speed?

Well I'll be.....

Right on Bond-o. Thanks for pointing that out. I was thinking it should have reved out higher. Downloaded the service manual and indeed the spec range is 4200-4600 rpm for the 330 model. The 370 model is 4800-5200.

This Searay was right at the high end, so she's propped pretty good as is, and there must be nothing too wrong with the motor. Buyer paranoia eh?

I hope that speedo meter is reading wrong though, like too slow!!!

 

[HT32BSX115]

Re: 86 Searay Sundancer 270. What WOT top speed?

I hope that speedo meter is reading wrong though, like too slow!!!

That's a BIG HEAVY boat!

Don't expect it to be a hot rod with only 330 crankshaft HP.....you're only doing around 300 at the prop!


Cheers,


Rick

 

[haulnazz15]

Re: 86 Searay Sundancer 270. What WOT top speed?

Agreed. If the speedo was ever 1-2mph off, low to mid-30's for a heavy boat like that WOT is probably correct. That doesn't mean that the engine was running perfectly, but I wouldn't expect to get much more out of it.

 

[bnicov]

Re: 86 Searay Sundancer 270. What WOT top speed?

It's a big boat for 1 motor even if it is a 454. If she had 2 engines, then you'd be into the 40's. Besides, running her flat out all the time will mean that you and the attendant at the gas dock will become great friends.

 

[TilliamWe]

Re: 86 Searay Sundancer 270. What WOT top speed?

... TRS outdrive. ... Boat is in fresh water (Lake Ontario) so bottom should be good.

You know the TRS drive is obsolete, right? And that props for it (same as a Bravo 2) are over $500 new for aluminum! Marine growth still occurs in fresh water, so you can't assume the bottom is clean just for that reason. The fact that the engine hit WOT rpm range says the bottom was clean, though.

 

[kencat]

Re: 86 Searay Sundancer 270. What WOT top speed?

It's a big boat for 1 motor even if it is a 454. If she had 2 engines, then you'd be into the 40's. Besides, running her flat out all the time will mean that you and the attendant at the gas dock will become great friends.

LOL. Ya I know that. I was using the WOT speed as an indicator of the health of the motor. I wouldn't be putting it up there all the time for sure. I wasn't out long enough, and not being familiar with the trim settings etc. I wasn't able to see where the minimum planing speed/rpm was. A nice cruise seemed to be 25-26 mph at around 4000 rpm ( where the owner liked it), but that doesn't seem much lower rpm than max. Any ideas on what fuel consumption would be at a cruise? Would twin 4.3's be a better bet for this boat?

BTW, much appreciate all the responses here from everyone. Very helpful.

 

[kencat]

Re: 86 Searay Sundancer 270. What WOT top speed?

You know the TRS drive is obsolete, right? And that props for it (same as a Bravo 2) are over $500 new for aluminum!

Yes. I've been reading quite a bit about the lack of Merc support. Didn't know about the props. I'm pretty sure this Searay has the TR drive, because using my "hand span" measurement tool it was about 10" from cav plate to propshaft. It would make sense too that it would be a TR for a big heavy cruiser. Are TR props even more expensive?

I talked to a mercruiser dealer parts guy today, and he said it looked like most of the common items were still available ( I expected to get laughed off the phone when I asked about the parts availability), even upper gear sets. Not housings and stuff though. I am sitting on making a decision to buy based on the obsolescence issue though. My logical brain is saying run away right now, but the other impulsive part is in love with the boat and tired of looking and wanting to be on the water. I like the size and simplicity and toughness of the drive, and the velvet tranny shifts soooo nice. The question is can I get away without major trouble for the next 5 years or so, after which time I may want out of boating or willing to repower. It's a gamble to go ahead with it I guess. The only other choice I've seen with this exact boat model though is the twin 4.3. Most of the little alpha drives I've seen on these older boats aren't in great shape, and then there are two of them to rebuild even though parts are available. That TR drive may last for another 15 years as is (excluding clobbering immoveable objects however .

Still sitting on that fence right now though.

 

[TilliamWe]

Re: 86 Searay Sundancer 270. What WOT top speed?

TR props are the same I think. Konrad makes a direct replacement for the TR/TRS. It's big bucks, though.

 

[kencat]

Re: 86 Searay Sundancer 270. What WOT top speed?

TR props are the same I think. Konrad makes a direct replacement for the TR/TRS. It's big bucks, though.

YA. I've looked at their website. That would be a great solution though, if the TR died, if I could afford it. Although when the boat was ready for the graveyard (I may be there before the boat is) or just not worth much anymore, the Konrad might still be worth a decent amount used, after being pushed by a pidly 300 HP for 500 hours or so. Might not be too expensive an outlay in the end.

Any used Konrads floating around yet?

Thanks for the replys guys. Going out again tonight on it (with my gps this time). I'll let you know if I get it....

 

[Mcgruff690]

Re: 86 Searay Sundancer 270. What WOT top speed?

Hello

I have a 1984 Sundancer 270 with the same motor. I just replaced my TR drive with a Konrad 520 this season. Cost me about 5000$ used rebuild from Konrad factory. Great company to deal with. My sea ray cruises on plane at about 32 km/h (75$per HR) Wot is about 4500 @ 50 km/h (150$/ hr) but I RARELY get there. I swear I see the gas gauges moving down to E very quickly when at WOT. The boat is definitely not a speedster. But a good cruiser. Very wide beam and stable in chop. The velvet drive transmission is smooth as butter to shift! TR drives are very hard to find upper parts for. Lower is no problem, but for 2000$ more over just the lower I got my Konrad. Long story why I needed a new drive.....

If the hull is solid and the motor looks clean and the drive shifts nicely, you will not be disappointed with the 270 as a cruiser.