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Old 17-04-2020, 17:43   #46
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Re: How many hours is too many?

An oil analysis won’t tell you engine condition, it may point out some current problems but will not tell you the condition of the main and rod bearings, compression etc.

However if you have an oil pressure gauge, you can get a very good idea of how much wear there is, to begin with the engine should start almost immediately, and with little smoke. That is actually a good compression check cause without good compression they don’t start immediately, it takes several seconds until there is enough heat to run and of course they smoke at start up as there is excess fuel to be burned off, that’s an indicator that the upper cylinder/rings could be worn.
Throttle up the engine before it is warm to half max RPM, with cold oil that should tell you the oil pressure relief valve setting, it should hold close to that pressure under cruise, even at full operating temp, maybe not exactly, but within say 10%
Then after it’s warmed up well, pin the throttle wide open and hold it there for at least 5 min, boat is underway of course, watch for any overheating and once you have it as hot as it’s going to get back down to idle and watch oil pressure, I’d want to see about 1/3 of what cruise pressure is, if it’s real low, that is a strong indicator that the internals have excessive wear and it won’t hold pressure with hot / thin oil due to it leaking out the areas with excess wear.
Now sometimes a slick seller will put straight 50W oil in so that the pressure remains high, so watch for that.

On my motor I pulled the oil filter and cut it open to inspect, and changed the oil before the sea trial so I knew it had the right weight oil.

If you know what your looking for, I maintain you can tell more from an oil filter inspection than most any other inspection method.
There are of course articles and I’d bet YouTube videos on oil filter inspections, just don’t use a grinder or saw to open the filter as that puts a lot of metal in it. Use an oil filter cutter or a pipe cutter, a pipe cutter actually works pretty well.
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Old 17-04-2020, 17:52   #47
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Re: How many hours is too many?

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Originally Posted by a64pilot View Post
An oil analysis won’t tell you engine condition, it may point out some current problems but will not tell you the condition of the main and rod bearings, compression etc.

However if you have an oil pressure gauge, you can get a very good idea of how much wear there is, to begin with the engine should start almost immediately, and with little smoke. That is actually a good compression check cause without good compression they don’t start immediately, it takes several seconds until there is enough heat to run and of course they smoke at start up as there is excess fuel to be burned off, that’s an indicator that the upper cylinder/rings could be worn.
Throttle up the engine before it is warm to half max RPM, with cold oil that should tell you the oil pressure relief valve setting, it should hold close to that pressure under cruise, even at full operating temp, maybe not exactly, but within say 10%
Then after it’s warmed up well, pin the throttle wide open and hold it there for at least 5 min, boat is underway of course, watch for any overheating and once you have it as hot as it’s going to get back down to idle and watch oil pressure, I’d want to see about 1/3 of what cruise pressure is, if it’s real low, that is a strong indicator that the internals have excessive wear and it won’t hold pressure with hot / thin oil due to it leaking out the areas with excess wear.
Now sometimes a slick seller will put straight 50W oil in so that the pressure remains high, so watch for that.

On my motor I pulled the oil filter and cut it open to inspect, and changed the oil before the sea trial so I knew it had the right weight oil.

If you know what your looking for, I maintain you can tell more from an oil filter inspection than most any other inspection method.
There are of course articles and I’d bet YouTube videos on oil filter inspections, just don’t use a grinder or saw to open the filter as that puts a lot of metal in it. Use an oil filter cutter or a pipe cutter, a pipe cutter actually works pretty well.
These are good tips on WOT tests. A64pilot and I disagree on usefulness of oil analysis, but clearly he knows what he's doing. Only thinga I would add are this cannot be be performed on the hard, and would have an owners representative run the boat to WOT on sea trial vs yourself. If the engine is going to take a digger, this is when it will do it. It's still the owners boat so I wouldn't touch it. If he doesn't want to run it up to WOT and hold it there for 5-10 minutes, well, you're at an impasse.
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Old 17-04-2020, 17:53   #48
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Re: How many hours is too many?

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Not really. Boat needs to be in the water to cool exhaust. I suppose done sort of hose could be hooked up, but I don't thing that's practical. Engine needs to be brought up to temp. If you decide to pull an oil sample, should be pulled on a warm engine and not from the bottom of the pan.

Why is the boat on the hard? How would you sea trial and sail? If this is a rock bottom bargain, you take chances. Might work out fine. But might not too.

Good luck

Peter
In a word? Canada. Boat is along near Toronto. This time of year and for the next few weeks all boats are on the hard so it's a lot easier, with the exception of the engine test, sea trial to do a survey.
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Old 17-04-2020, 17:55   #49
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Re: How many hours is too many?

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These are good tips on WOT tests. A64pilot and I disagree on usefulness of oil analysis, but clearly he knows what he's doing. Only thinga I would add are this cannot be be performed on the hard, and would have an owners representative run the boat to WOT on sea trial vs yourself. If the engine is going to take a digger, this is when it will do it. It's still the owners boat so I wouldn't touch it. If he doesn't want to run it up to WOT and hold it there for 5-10 minutes, well, you're at an impasse.
Noted. Good point. I think I'll discuss the process I'd like to try and see if the response is positive. If not well, then I guess it's a pass.
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Old 17-04-2020, 17:59   #50
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Re: How many hours is too many?

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Originally Posted by a64pilot View Post
An oil analysis won’t tell you engine condition, it may point out some current problems but will not tell you the condition of the main and rod bearings, compression etc.

However if you have an oil pressure gauge, you can get a very good idea of how much wear there is, to begin with the engine should start almost immediately, and with little smoke. That is actually a good compression check cause without good compression they don’t start immediately, it takes several seconds until there is enough heat to run and of course they smoke at start up as there is excess fuel to be burned off, that’s an indicator that the upper cylinder/rings could be worn.
Throttle up the engine before it is warm to half max RPM, with cold oil that should tell you the oil pressure relief valve setting, it should hold close to that pressure under cruise, even at full operating temp, maybe not exactly, but within say 10%
Then after it’s warmed up well, pin the throttle wide open and hold it there for at least 5 min, boat is underway of course, watch for any overheating and once you have it as hot as it’s going to get back down to idle and watch oil pressure, I’d want to see about 1/3 of what cruise pressure is, if it’s real low, that is a strong indicator that the internals have excessive wear and it won’t hold pressure with hot / thin oil due to it leaking out the areas with excess wear.
Now sometimes a slick seller will put straight 50W oil in so that the pressure remains high, so watch for that.

On my motor I pulled the oil filter and cut it open to inspect, and changed the oil before the sea trial so I knew it had the right weight oil.

If you know what your looking for, I maintain you can tell more from an oil filter inspection than most any other inspection method.
There are of course articles and I’d bet YouTube videos on oil filter inspections, just don’t use a grinder or saw to open the filter as that puts a lot of metal in it. Use an oil filter cutter or a pipe cutter, a pipe cutter actually works pretty well.

I think, other than the basic steps (cold start, exhaust colour etc) that I need to understand the maintenance and why it was run 140~ hours per year. Apparently it's an AME that owns it now. I'm a non current pilot as well.

Boat is in the St Lawrence so it's not crazy to motor a lot. Just seems high for our season of 5-6 months.

Other than the engine what other parts need to be inspected? Bushings, prop shaft, etc..? The whole powertrain has 4000 hours on it.
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Old 17-04-2020, 18:00   #51
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Re: How many hours is too many?

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How many years of human life is too many? Sure there were a few who lasted 115-120 years, 122 I beleve is the documented world record. But a good number living reasonably healthy lives without catastrophic events, getting timely medical help, no booze or smokes in excess and with a bit of luck thrown in will expect to last between 80 and 90 years. So even uynder the almost ideal conditions that's well short of the apparent capability of around 120. And not living healthy lives in a unhealthy environment life expectancy is much shorter than that.
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Old 17-04-2020, 18:03   #52
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Re: How many hours is too many?

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I agree. And that’s the killer. Sitting unused. Mostly all of the ancillary parts around the core start going bad. But I’m sure there are some internal things going wrong also while things sit and rot.

But as is the case whenever we all talk boats, you and I are talking about two different things. Happens all the time on this forum. I’m thinking of one type of engine, you’re thinking of a whole different thing. When you are talking about our small engines, we don’t have the same engine.

I have a Perkins 6.354. Nearly identical to the Cummins turbo diesel in my truck.

354 cubic inches (5.8 litres) 120 BHP at 2800 RPM. Very close match, minus the turbo part. The Perkins is of course naturally aspirated being in an older boat that I have.
How would sitting on the hard for 6 months of winter shrink wrapped affect the engine? What's the correct winterization procedure?

Also, would being indoors on the hard, unheated, result in better results?
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Old 17-04-2020, 18:12   #53
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Re: How many hours is too many?

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Originally Posted by pbyrne View Post
I think, other than the basic steps (cold start, exhaust colour etc) that I need to understand the maintenance and why it was run 140~ hours per year. Apparently it's an AME that owns it now. I'm a non current pilot as well.

Boat is in the St Lawrence so it's not crazy to motor a lot. Just seems high for our season of 5-6 months.

Other than the engine what other parts need to be inspected? Bushings, prop shaft, etc..? The whole powertrain has 4000 hours on it.
Prop shaft should rotate easily by hand. If it doesn't, it's out of alignment. Since it's on the hard, you can wiggle the shaft from the outside to see if there is any lash. Would indicate a worn cut less bearing. Prop should not have pink discoloration which indicates galvanic corrosion. Rudder should not be loose - indicator of worn rudder bearings. Underway, the transmission should shift smoothly and without delay. Pull the dip stick and smell. Any burned smell might be an indicator of an issue. Check bulges for water (or signs of water). Not a huge deal but a chronic leaking stuffing box is a small yellow flag. Underway while motoring, check temp of stuffing box. It should be barely warm. If it's hot, it's grinding the shaft. Not a huge expense on a boat this size, but easily $1k by the time your done. Check hoses and valves to make sure they are in good shape - it's surprisingly expensive to replace if needed.

140 hours of annual run time is good. Means the boat was run regularly and used.
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Old 18-04-2020, 10:19   #54
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Re: How many hours is too many?

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Originally Posted by pbyrne View Post
So:
1) First engine check is cold start.
2) Second check would be exhaust
3) Third check is blow by.
4) Fourth check is underway sea trial.
5) Finally, oil analysis.

The above is pretty reasonable to do. A compression test, which messes with someone else's engine, seems like a big ask. Can these test be run (other than sea trial) on the hard?
Yes, 1,2,3 and 5 can easily be done on the hard. I've done it countless times, that's how boats up north get winterized. You need to either remove the RW hose from the seacock or strainer and run the appropriate sized hose into a 5 gal. bucket exterior to the boat with a constant supply of water going into the bucket.
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Old 18-04-2020, 10:33   #55
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Re: How many hours is too many?

To quote my father, "Running a displacement boat is like running a truck uphill all the time."
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Old 18-04-2020, 11:50   #56
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Re: How many hours is too many?

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To quote my father, "Running a displacement boat is like running a truck uphill all the time."
Sorry, I don't get it. What's the message?
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Old 18-04-2020, 11:52   #57
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Re: How many hours is too many?

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Yes, 1,2,3 and 5 can easily be done on the hard. I've done it countless times, that's how boats up north get winterized. You need to either remove the RW hose from the seacock or strainer and run the appropriate sized hose into a 5 gal. bucket exterior to the boat with a constant supply of water going into the bucket.
Good to know! That's true isn't it. You can't leave water in the boat over winter.

Just out of curiosity, do you think that's a crazy thing to ask to do..?
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Old 18-04-2020, 12:01   #58
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Re: How many hours is too many?

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Prop shaft should rotate easily by hand. If it doesn't, it's out of alignment. Since it's on the hard, you can wiggle the shaft from the outside to see if there is any lash. Would indicate a worn cut less bearing. Prop should not have pink discoloration which indicates galvanic corrosion. Rudder should not be loose - indicator of worn rudder bearings. Underway, the transmission should shift smoothly and without delay. Pull the dip stick and smell. Any burned smell might be an indicator of an issue. Check bulges for water (or signs of water). Not a huge deal but a chronic leaking stuffing box is a small yellow flag. Underway while motoring, check temp of stuffing box. It should be barely warm. If it's hot, it's grinding the shaft. Not a huge expense on a boat this size, but easily $1k by the time your done. Check hoses and valves to make sure they are in good shape - it's surprisingly expensive to replace if needed.

140 hours of annual run time is good. Means the boat was run regularly and used.
That makes sense to me as well. Compared to the other C30's that are comparable, 4000 is a lot higher.

Assuming running the engine just to get out of the harbour is worse than motorsailing a lot, and with so many so many boats in the 1000-2000 hour range of the same year or older, do they have more problems?

It doesn't seem so...
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Old 18-04-2020, 12:04   #59
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Re: How many hours is too many?

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Good to know! That's true isn't it. You can't leave water in the boat over winter.

Just out of curiosity, do you think that's a crazy thing to ask to do..?
Correct you cannot leave salt or fresh water in an engine if there is any chance of temps going below freezing. If I followed this thread correctly the boat in question is located in Ontario, so it would have been winterized. If you ask to start and run the engine on the hard it will be your responsibility to winterize the engine and exhaust system upon completion of your pre-purchase tests.

There's no harm in asking but there may be more to starting the engine than just feeding it water, are the batteries on board, is the RW pump disassembled, is the fan belt tensioned? Best to have a conversation with the owner/broker to determine what's required and then determine if the work can be performed during the Covid 19 lockdown if any.
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Old 18-04-2020, 13:12   #60
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Re: How many hours is too many?

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Yes, 1,2,3 and 5 can easily be done on the hard. I've done it countless times, that's how boats up north get winterized. You need to either remove the RW hose from the seacock or strainer and run the appropriate sized hose into a 5 gal. bucket exterior to the boat with a constant supply of water going into the bucket.
Could it be done? I guess. But not practical to do on the hard. Boat needs to be brought up to temp and really should be under load. I guess you could hook up a garden hose to the raw water intake and run for 20+ minutes. Careful about flooding the exhaust.

Besides being an interesting science project, what would be the benefit of doing it on the hard?
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