NB Engine vs Car- problems

[Ronniesonic]

Hi All- I am not a mechanic as this post will probably prove... However I have a simpleton question of comparison;

 

I just got thinking that my last 3 works cars were diesel & I covered over 150k in them without a single breakdown, just serviced as per manual. I gauge that NB Diesel Engines fail more pro-rata than a Car Engine.

 

If this is actually true, & now having read it back twice I am not convinced, what are the main reasons for this?

I am thinking a modern BETA (others are available) & not older Engines. My 1st Car was a Chevette & was always off the road!

 

My coat is ready if you don't go easy on me.

[Keeping Up]

I do not think you can say that narrowboat engines fail more pro-rata than car engines. If a car averages 50mph, then it can cover 150k in just 3000 hours. Most narrowboat engines will go for much longer than this without needing any more than routine servicing - ours has done 3 times that much over a period of 20 years but admittedly it has broken down three times (once needing a new oil seal, once needing a new injector pump, and once needing the replacement of a brass core plug)

[Iain_S]

Each boat is a different installation; unlike cars which are virtually identical across each model. Most failures, IMO, are due to the installation; pipes chafing, insufficient cooling, etc, etc.

 

Boat fuel tends to get a bit more contaminated than road vehicle fuel, as there is a larger quantity which sits around the tank for longer.

 

I find, however, that boat engines usually give more warning of potential failure than cars, even if it's just a worn bit on a rubber pipe.

 

Your 150k (I'm assuming 150,000 miles ) probably equates to between 3000 and 6000 hours. That's low for most boat engines, many of which go on past 10,000 hours without major problems.

 

Just my thoughts,

 

Iain

[Speedwell]

I can see no reason why properly maintained boat engines should not be as reliable as car engines, however there are several factors against boat engines. Many live in a very wet environment, with attendant corrosion problems, not to mention water getting in the fuel system. Many engines are victims of less than optimum marinisations such as poor cooling and ill fitting attachments. Many, if not most, operate under load cycles for which they were not intended.

If you can avoid all these things, your engine should have a long and happy life.

Arthur

[Proper Job]

You'd be lucky to average 50 mph on the life of a car.

 

I remember reading a while back that the average speed of a car over it's life time was less than 30 mph

 

At that speed 150K mile would equate to 5,000 hours.

 

Theoretically, boat engines should be a lot less stressed than car engines. They run at fairly constant loads and for long periods of time.

[Keeping Up]

You'd be lucky to average 50 mph on the life of a car.

 

I remember reading a while back that the average speed of a car over it's life time was less than 30 mph

 

At that speed 150K mile would equate to 5,000 hours.

 

Theoretically, boat engines should be a lot less stressed than car engines. They run at fairly constant loads and for long periods of time.

 

Ah but works cars go a lot faster than privately owned ones.

 

And if the OP has covered 150k miles on each of three cars then I'd guess that a lot of the time is spent on motorways or other high-speed roads.

[nb Innisfree]

If boat engines are generally less reliable I would put it down to underuse i.e. unlike car engines which mostly get used in their correct rev range and therefore reach proper working temp. so avoiding problems associated with cool running.

[John V]

If boat engines are generally less reliable I would put it down to underuse i.e. unlike car engines which mostly get used in their correct rev range and therefore reach proper working temp. so avoiding problems associated with cool running.

 

You might have something there, especially if you add glazed bores from battery charging.

[n.b.Goldie]

I agree that poor installations are a common cause of problems with narrowboat engines. Narrowboats are 'garden shed' engineering rather than the high tech engineering involved with the motor industry.

 

Having seen the installations in a couple of new build boats at our boat club I wonder whether boat builders have any understanding of engineering principles let alone the physics of cooling systems. Disgraceful given the sums charged by these cowboys.

 

Regards

Ditchdabbler

[Alan Saunders]

If boat engines are generally less reliable I would put it down to underuse i.e. unlike car engines which mostly get used in their correct rev range and therefore reach proper working temp. so avoiding problems associated with cool running.

Yes, diesel car engines, especially the modern, turbo-charged ones fail due to short trips when they do not reach operating temperature.

 

Sometimes an old petrol engine can be revived by a 70mph blast in third gear!

[luctor et emergo]

Yes, diesel car engines, especially the modern, turbo-charged ones fail due to short trips when they do not reach operating temperature.

 

Sometimes an old petrol engine can be revived by a 70mph blast in third gear!

 

Ahh, the old 'Italian Tune-up'

[PaddingtonBear]

We give our PD2 an Italian tune up on the Trent - thoroughly recommended.

[Keeping Up]

Italian tune-up on the Trent worked wonders on our MC42 as well. It had been running on 3 (out of 4) cylinders for a year; after an hour at full throttle stemming a fast ebb tide outside Stockwith, all 4 were again in perfect harmony.

[Chalky]

I agree that poor installations are a common cause of problems with narrowboat engines. Narrowboats are 'garden shed' engineering rather than the high tech engineering involved with the motor industry.

 

Having seen the installations in a couple of new build boats at our boat club I wonder whether boat builders have any understanding of engineering principles let alone the physics of cooling systems. Disgraceful given the sums charged by these cowboys.

 

Regards

Ditchdabbler

 

It's not just that - the understanding of drive couplings is also "interesting". especially when coupled to a flexibly mounted engine... Also The engine electrics would never pass even the most basic automotive quality audits.

[nb Innisfree]

Italian tune ups work by giving the combustion chambers and valves a superheated steam clean.

[Proper Job]

Italian tune-up on the Trent worked wonders on our MC42 as well. It had been running on 3 (out of 4) cylinders for a year; after an hour at full throttle stemming a fast ebb tide outside Stockwith, all 4 were again in perfect harmony.

People forget that diesel engines like to work hard & hot.

 

It's really handy at Thrupp having the river Cherwell section of the canal locally. By the time I get to Shipton the engines nicely up to temperature. The 1000rpm blast up to Bakers lock really clear things out and after that ye olde JP runs a sweet as a nut

[Chalky]

Italian tune ups work by giving the combustion chambers and valves a superheated steam clean.

 

It's not just the combustion chambers. Modern car diesels have particulate filters that require "cleaning" by taking the car for a long fast run to get them hot and burn the accumulated soot. Used round town they could potentially clog up to the point where they have to be removed and professionally cleaned unless they get the occasional Italian tune up.

[John V]

It's not just the combustion chambers. Modern car diesels have particulate filters that require "cleaning" by taking the car for a long fast run to get them hot and burn the accumulated soot. Used round town they could potentially clog up to the point where they have to be removed and professionally cleaned unless they get the occasional Italian tune up.

 

After an Italian tune up do you have to re-tighten the head with an Italian torque wrench? (YOU PULLITA TILLITSA TITE)

[Grace and Favour]

After an Italian tune up do you have to re-tighten the head with an Italian torque wrench? (YOU PULLITA TILLITSA TITE)

 

An Italian talk wench would say (You pushita tillitsa tite?)

[John V]

An Italian talk wench would say (You pushita tillitsa tite?)

I refuse to go further down that road