How many hours is too many?

[Cadence]

Originally Posted by pbyrne

Sorry, I don't get it. What's the message?

It is that it is under load all the time.

[pbyrne]

Originally Posted by mvweebles

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?

Science for the sake of pure learning of course!

Boat is in Ontario, Canada. No boats like this stay in the water for winter if you like them.

As it's on the hard, a survey would be cheaper at this time, especially if the owner is going to put in. Survey after put in means crane expense. Which I can avoid at this time of year.

[pbyrne]

Originally Posted by Cadence

It is that it is under load all the time.

Got it!

[kenbo]

Originally Posted by mvweebles

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?

It seems to me that your not familiar with winterizing marine diesels believe me it's not a science project. Every boat in the northeast and on the great lakes does this every fall.

The advantage is if some deal breaker becomes apparent upon the cold start you can save the time and place expense of the sea trial.

[pbyrne]

Originally Posted by kenbo

It seems to me that your not familiar with winterizing marine diesels believe me it's not a science project. Every boat in the northeast and on the great lakes does this every fall.

The advantage is if some deal breaker becomes apparent upon the cold start you can save the time and place expense of the sea trial.

That's my thinking too. Hence why I asked. I'm not sure if that's something that is common place to ask up here in the frozen North though.

I guess it comes down to whether or not the owner is planning on putting in to sail for the season or not. If not then I think it's very reasonable to request this test, with the PITA factor...

[mvweebles]

Originally Posted by kenbo

It seems to me that your not familiar with winterizing marine diesels believe me it's not a science project. Every boat in the northeast and on the great lakes does this every fall.

The advantage is if some deal breaker becomes apparent upon the cold start you can save the time and place expense of the sea trial.

Exam question was not about winterizing an engine. It was about tips on evaluating an engine in contemplation of purchase. This is not a particularly valuable boat. Maybe the OP is okay taking a chance with a partial engine survey. It's a judgment call. But let's be fair. It's a compromised approach to do it on the hard when the engine is not under load and you're spewing water all over, perhaps over filling the exhaust and damaging the engine

I stand by my guidance. Somebody wants to do a workaround!? It's their call.

[mvweebles]

Originally Posted by kenbo

It seems to me that your not familiar with winterizing marine diesels believe me it's not a science project. Every boat in the northeast and on the great lakes does this every fall.

The advantage is if some deal breaker becomes apparent upon the cold start you can save the time and place expense of the sea trial.

As an aside, I've owned a cabin at 8500 ft elevation in the Colorado mountains for 30 years, a few where I lived there year round. I am not a stranger to winterizing machinery. But again, that was not the OPs question.

[kenbo]

I disagree. I believe it was his central question.

[mvweebles]

Originally Posted by pbyrne

I'm looking at a 91 Catalina 30 with an M25 that has about 4000 hours, alternator and injectors done in the last 2 years. Fresh water.

What should I be looking for with respect to condition, other than the obvious things like leaks? Apparently it was 'looked after' but I'm uncertain how many hours before a rebuild, and what other parts may need attention with that many run time hours. Shaft bearings etc.

Also, what's the typical cost to rebuild, assuming you do it in boat.

I'm sorry, what part of this is "how do I winterize an engine" or "is it possible to adequately evaluate an engine when it's in a cradle?"

[kenbo]

Originally Posted by pbyrne

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?

This is what I was responding to. Seems fairly central to me.

[mvweebles]

Originally Posted by kenbo

This is what I was responding to. Seems fairly central to me.

Gotcha. Apologies if I over reacted.

If the OPs question is along the lines of "I'm about to pay $5k for a $12k boat but want to make sure I'm not stuck with a POS motor because it's on the hard," well, that's a different question. Bar gets lowered

[kenbo]

No worries, sometimes on a longish thread like this the topic can drift.

[pbyrne]

Originally Posted by mvweebles

Gotcha. Apologies if I over reacted.

If the OPs question is along the lines of "I'm about to pay $5k for a $12k boat but want to make sure I'm not stuck with a POS motor because it's on the hard," well, that's a different question. Bar gets lowered

Firstly, I appreciate you comments! @Kenbo too.

Both of you get the idea of what I'm trying to do. I suppose I did get a bit more focused as it went.

With respect to above, you're not half wrong. In essence, I'm trying to establish a reference point of how to evaluate the engine hours, as I plead ignorance of this topic, and am trying to learn.

The boat is on the hard at the moment because it's still snowing in spring here, Toronto way. Put in for us is usually Mid May, haul out Mid Oct.

While it's on the hard I'm making an assumption that a survey would be cheaper and easier, with the exception of the engine or sea trial.

I don't know if the owner plans putting in at all this year, if not, then I guess on the hard will have to do. If he does, then survey on the hard before put in, then engine and sea trial post put in.

Aside from that, I have little to no experience with marine engines.

My impression at this point is that while diesels can run up into many 1000's of hours, it doesn't seem to be typical. I hadn't considered just how low the hours were on other boats. Which, no that I'm better informed, makes me question the low hours.

I'd be interested in knowing how high hour engine boats vs low hour engines of boats of the same age, and basic maintenance (roughly) compare. It seems that the low hour engines may have more issues.

[mvweebles]

Sounds like seeing if engine starts promptly when cold should be easy. Also, I was mistaken in one item: garden hose should NOT be hooked up to the intake of the raw water pump directly. As someone else mentioned, the intake should be put into a bucket, and the bucket filled with a garden hose. This will prevent back filling the exhaust and allowing water to enter the exhaust side.

I'm curious. How does a 1991 Catalina 30 that is laid up for over half the year accumulate 4000 engine hours? Cruised to the Bahamas a few years? Normally, boats like these do not have much noise insulation and this isn't a particularly smooth engine so it's not exactly something that would endear itself to long motoring. 4000 hours is equivalent to over two years of full time 8-hr/day work. Just seems like an unusually high number of hours on a boat like this given its laid up half the year.

Just curious. Not a huge deal.

[Dockhead]

Originally Posted by kenbo

This may only confuse the issue further but many OTR truck diesel engines makers have shifted the metric for maintenance and overhauls from hours to amount of fuel burned.

Hours on the clock can be and often is a misleading measure. But if you have historical records of fuel purchased/burned you have a very accurate picture of the work the engine has performed over the service time period.

In my opinion hours is not very revealing. There have been some excellent suggestions made in earlier posts about how to evaluate a used engine and I vote to include an oil analysis as long as you know when it was changed and with what brand/type of oil.

That's the way BMW has done their service interval indicator for decades. Makes sense.


Hours is even less revealing if you consider RPM. An hour at 1500 RPM is not the same as an hour at 3000 RPM.


That's why sport fish boats get so few hours out of an engine -- as A64 said, they are run wide open most of the time, so perhaps double the actual revolutions per hour compared to ours, and at much higher thermal and mechanical stress.