Potential first sports cruiser?

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uncharted

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Hi everyone, new to the forum. Having read lots of useful articles here to get started, I recently went to view a 27ft Monteray with a diesel yanmar 6-315hp and there are a few concerning issues, which, though I am handy on the tools, I'm looking for something to enjoy some downtime on, not another full time job, what would you good folk think re costs to fix these issues...
1. Thru hull looks nok? 1inch of water entered the bilge after we dropped the boat in the water, and did a sea trial. Could be just loose/freeze damaged joints in the heads feed?
2. Water pump leak? Rust around base
3. Turbo failed? 3800rpm gave 19knts max. Interesting that it looks like a connection is missing from the top in attached photo.
22pitch prop on a bravo1x drive with 1:1.65 ratio. Boat is 3 tonnes (manuf figures)
Very little if any smoke. Ran up fine, just with no real power.
4. Usual small leaks from coolant pipe ends (20year old yanmar) evident at the exhaust elbow, and on the cooler ends.
Is it something worth getting into? Thanks all.
 

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At that age you need to check the transom shield where the steering arm enters the engine room, they are prone to leak here as water runs in under the steering arm and eventually requires a whole new transom shield
 
How to eliminate 50% of the causes of the unwanted water.
The Taste Test. Salt or fresh (ish) all at your own risk of course.👅
Fresh. Possibly a leaking fresh water system or rainwater/condensation pooling due to water draining back due to boat being underway.
Fresh. But with a destinctive taste and smell of anti- freeze usually an interesting tint of pink,might be a simple as hoses or something more complicated and expensive, an internal boat problem and probably mendable with boat in water
Salt.
Raw water engine cooling, possible again hoses, or more worryingly the system itself including the various heat exchangers (oil/ main heat exchanger/ after coolers etc) and exhaust risers, all guaranteed to corrode over time.
If outdrives, possible leaks via the rubber bits supposed to keep water out of the boat, this will require the boat out of the water to be fixed.
Worst of all. Leaks around the transom assembly to transom joint.
If caught early enough remove and reseal, if not ,could involve considerable time and expence to replace or rebuild the stern of the boat.
Usually a decent torch and a the Mk1 eyeball will trace the source of the water.
3800 rpm is about right at WOT.

Good Luck.
 
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uncharted said:
3. Turbo failed? 3800rpm gave 19knts max. Interesting that it looks like a connection is missing from the top in attached photo.
Click to expand...
It's got the wrong prop on it. Should be getting a far higher figure (circa 30 knots) at 3,800rpm. It's like trying to max a car in third gear, it does the max revs but not the max speed (or anywhere near).

Intrigued to know why you think it equated to a failed turbo?
 
ari said:
It's got the wrong prop on it. Should be getting a far higher figure (circa 30 knots) at 3,800rpm. It's like trying to max a car in third gear, it does the max revs but not the max speed (or anywhere near).

Intrigued to know why you think it equated to a failed turbo?
Click to expand...
During the sea trial, it was a smooth acceleration, but with no discernable boost, and lacking power all though the revs, as though it was putting out 150hp not 300+. And the fact the current owner has down pitched to a 22 suggests that was their solution to the deterioration of power, rather than addressing the root cause, although there was very little smoke, so perhaps it could be a fuelling restriction?
 
I'd be surprised if there's a turbo issue if the engine can still pull 3800 RPM in gear/under load? When the 6LP turbo on my 9m Ribtec popped it wouldn't go above ~2000RPM in gear. The coolant "leaks" don't look particularly fresh, more that some has leaked out during servicing and not been tidied up promptly? As above, I'd want to check the outdrive carefully having rebuilt the transom shield on my Bravo 3X - very common to get play in the OEM gimbal ring/tiller arm, rusted gimbal bearing, leaking gear/drive bellows, worn out clutch cones, etc., all of which can be very expensive to put right, even doing the labour yourself.
 
What to look for when buying an old motor boat.
I bought a 25 year old boat with a Yanmar 140 hp Diesel. I tried it out and the bilge started to fill with water,
It turned out that the rubber exhaust pipe where it connected with the skin fitting had perished and was leaking into the boat.
These rubber pipes have a metal coil within them for strength and when the rubber gets soft with age water reaches the metal coil and it starts to rust, after a time the metal coil gets thinner and splits, what happens then is the broken coil flicks up through the rubber and when the engine is run water seeps out into the bilge.

If I had taken the boat to a boatyard to be fixed It would have cost a lot to fix, where the defective exhaust pipe connected to the skin fitting it could not be reached, it was located behind and underneath the diesel tank and to get that out I had to cut out a section of the grp moulding which formed the rear seat across the back of the cockpit.

With the diesel tank out I could reach the skin fitting and replaced the pipe. The tank went back in and I did a gel coat repair on the 8 foot section of the seat moulding which I had taken out by using an electric saw.

Sometimes enjoying boating isent just tearing around at 25 knots.
 
paulbrown22 said:
I'd be surprised if there's a turbo issue if the engine can still pull 3800 RPM in gear/under load? When the 6LP turbo on my 9m Ribtec popped it wouldn't go above ~2000RPM in gear. The coolant "leaks" don't look particularly fresh, more that some has leaked out during servicing and not been tidied up promptly? As above, I'd want to check the outdrive carefully having rebuilt the transom shield on my Bravo 3X - very common to get play in the OEM gimbal ring/tiller arm, rusted gimbal bearing, leaking gear/drive bellows, worn out clutch cones, etc., all of which can be very expensive to put right, even doing the labour yourself.
Click to expand...
Any other ideas on why she would be down on power? Oil pressure and temp were both good.
 
@uncharted - The boat market is dead thus meaning as a buyer you have 1000's of boats to choose from.
even if you see a boat that maybe a little out of budget a fair offer is likely to be accepted.
Don't rush for the first boat you see - go with your head not your heart.

here's a diesel for sale around 27ft For Sale 2005 Doral Monticello - Boats.co.uk
 
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uncharted said:
Any other ideas on why she would be down on power? Oil pressure and temp were both good.
Click to expand...
I guess it could still be a number of things, and would need a detailed inspection if really down on power. Is it definitely working on all 6 cylinders, potentially an injector issue, potentially a fuel pump issue, potentially clogged intercooler, potentially wrong prop, potentially replacement outdrive with the wrong ratio, potentially someone has replaced an internal drive gear with a different ratio, etc.

Definitely currently a buyers market, so unless it's an absolute bargain price and worth a risk, or the seller wants to investigate/fix given it should be a 30kn boat, keep looking around.
 
"potentially wrong prop,"
WOT gives 3800.rpm.

If wrong prop..
Over pitched... will not reach max revs.
Under pitched it would revs its little socks off.

General rule 1" = 200 rpm ?
 
oldgit said:
"potentially wrong prop,"
WOT gives 3800.rpm.

If wrong prop..
Over pitched... will not reach max revs.
Under pitched it would revs its little socks off.

General rule 1" = 200 rpm ?
Click to expand...
Agreed, unless it's under propped and hitting a governor or similar at 3800? In any case I agree - sounds like more than a case of wrong prop regardless given the current performance!
 
TBH and in my exp[erience even a half decent boat will give you enough problems to keep you busy. A mate bought a boat from Ireland a few years ago and asked me to go over an bring it back with him (Offshore 105 work boat). When I saw the boat I asked him if he'd already paid for it ( he had) becuase otherwise we'd have been back to the airport and on the next flight home! It took months to sort once we got home. As others have said unless it's an absolute bargin, there are plenty of others out there - don't get fixated on one boat.
 
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