Idled once a week, was that a good thing?

[dhmeissner]

That's the best, clearest, most knowledgeable first hand account I've seen on this thread. I feel you can... "take that post to the bank"!

 

[f508]

Commercial fishing, I idled a diesel (trolling for salmon) at 600 rpm 10-14 hours a day, but ran in and out at speed. For tuna, I stayed out and drifted at night. Trolling at 900 rpm for as long as 2 weeks. I always get longer intervals between overhauls than other people. Mostly from low EGTs and clean oil.
Idle to operating temp weekly is much better than not running. It keeps the cylinders lubed and drives out moisture.

Thanks for the info. What engines were those?

 

[psneeld]

Almost all offshore gamefish sportfishers are idled under load for long days while trolling but get a good run out and in usually.

Some T boats do drift not under load, but usually come up to speed every 15 minutes or so for another drift. They are usually warm to temp throughout the process.

Even truckers letting tbeir engines idle have some load on them....

And that is the rub more than idle or higher rpms....is their a load, are the cylinder temps up?

Just pulled my Lehman head and awaiting expert analysis on cylinder condition. I did have some carbon from my constant low engine temps while cruising at 1700 or so rpm. Next season...will see what temps 1800 rpm brings.

 

[koliver]

Commercial fishing, I idled a diesel (trolling for salmon) at 600 rpm 10-14 hours a day, but ran in and out at speed. For tuna, I stayed out and drifted at night. Trolling at 900 rpm for as long as 2 weeks. I always get longer intervals between overhauls than other people. Mostly from low EGTs and clean oil.
Idle to operating temp weekly is much better than not running. It keeps the cylinders lubed and drives out moisture.

Way back when there were no fishing restrictions (1967 I was there) the above was the whole Pacific Salmon Trolling fleet. There were a few boats with freezers that would take longer than 2 weeks to fill their hold with fish, so stayed out longer. The rest of us went back in when two wekks was up, as the ice would be getting soft and the iced fish needed to get to market within that time. The run in at speed was 12 to 20 hours long.
Ours was a Jimmy 6V71. No issues.

 

[FF]

"If he ran it against the dock lines, loading the engine, raise the temp to operating range, then no issues I can see."

The issue here is the operating prop can scour material from the slip and pile it up behind the boat.

In really deep water its no problem , in shallow locations it can block a channel.

To warm up an engine a modest load is required , say 25% .

A 100 HP diesel would need a 25 HP load .

At 20 lbs of thrust per hp, 20 x 25 = 500.

So the slip , cleats and lines would need to resist 500lbs of tugging for 1/2 hour or so. 1,000 lbs with twins.

 

[what_barnacles]

If your lines cant hold 500 pounds of tugging on them you may be using yarn.

 

[jwilsail]

I run at the dock once per week. I like to run alternating gears so port will be in forward while starboard is in reverse and switch halfway through the run. This limits the load on the dock, also since the boat is not moving it increases the load on the engines compared to the same rpms on a moving vessel. I can keep the starters batteries isolated from the house bank and I think it helps with the growth on the bottom and the running gear.

 

[rwidman]

508,
.............Declaring something to be bad on a forum frequently goes over the top and people avoid it like a plague..................... .

There is a lot of misinformation on the Internet and especially on forums where everyone is an "expert".

Running or not running an engine is one of the things that people argue over all the time on web forums. And "mechanics" are no better, they don't agree and many "mechanics" have never had factory training (or any formal training). If it was possible to ask the manufacturer, that would be the only "correct" answer.

Some folks think you need to run a boat's engine every week or two but keep in mind that in northern regions, boats are often hauled and set on land for six or more months every year. The engines are not run on these boats during that time and they seem to do fine.

 

[psneeld]

1. Actually boats that sit dont do fine compared to those that run often, but correctly. Or the ones that do well have more done to them than those just shut down without other preventative maintenance for the season. I see it all the time working as an assistance tower and working in marinas....not something I read on the internet or boating magazine or learned from a handful of boat friends.

2. Real operators are those that either prove or disprove the manufacturer engineers design and concept. Sometimes the engineers are proven wrong. As in tbe Ford Lehman. If the history that I have read is true, it was designed as a truck engine but proven tl be more reliable as an engine run at more constant speeds and load as in agricultural equipment and boats.

 

[Art]

1. Actually boats that sit dont do fine compared to those that run often, but correctly. Or the ones that do well have more done to them than those just shut down without other preventative maintenance for the season. I see it all the time working as an assistance tower and working in marinas....not something I read on the internet or boating magazine or learned from a handful of boat friends.

2. Real operators are those that either prove or disprove the manufacturer engineers design and concept. Sometimes the engineers are proven wrong. As in tbe Ford Lehman. If the history that I have read is true, it was designed as a truck engine but proven tl be more reliable as an engine run at more constant speeds and load as in agricultural equipment and boats.

And... many sizes/styles of GM, Ford, Chrysler gasoline engines were designed to be car and small truck engines but later found to be great boat engines too, once they were marineized.

Wasn't till [I believe GM mainly, maybe Chrysler to a certain extent, Ford I'm not so sure of] began well over a decade + ago to try and make large gas engines become morphed into diesel engines that it became proven... engines designed to run on gasoline and engines designed to be run on diesel need to be kept distinct in regards to design.

I'm not sure, but due to improved engine design technology it may be that the two different engine design types are again beginning to merge.

I bet you can fill in my blanks!

Engineers are similar to doctors... in that both professions are constantly practicing in attempt to get "it" right so advancements can be made and then proven-out for the long run.

 

[FF]

"keep in mind that in northern regions, boats are often hauled and set on land for six or more months every year. The engines are not run on these boats during that time and they seem to do fine."

Most engine service books have the Mfg procedure for "Out of Service for over 30 days".

 

[mbevins]

I can say that up North where we use heated indoor storage. The boat is basically hauled, washed and blocked indoors. There is no winterizing of the engine. Over the years I've stored at three different facilities, all the same procedure. The engines sits from mid October till mid April/May I've never heard of any issues.