Routine Engine Start

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DrQ

Member
Joined
Aug 12, 2019
Messages
17
Location
USA
Vessel Name
Deep Blu
Vessel Make
1990 46' BestWay Sundeck Trawler
Does anyone have any suggestions about starting and warming up the engines.

Is this something you do weekly at the marina?

What do you do before starting, what to look for when running?

How long do you run the engines?

What other suggestions do you recommend?

Thank you in advance!!!
 
The question is what engine. Starting my diesel to warm it up is fruitless. I must load it at 1200 to start to make heat. So idling at the dock will just hurt it. I run my boat 5 time a week so not an issue for me. During end of season when I don’t use it as much , I run the generator under load at the dock. That knock out the ER moisture real quick. And helps the GEN stay happy. A gasser is a different story.
 
I have twin Volvo Penta Tamd 61-A Turbo Diesels. I start them up and ru. For 30 minutes. Erving up half way to 1100RPMs. I live aboard down in Florida
 
Gentlemen, do a search here on this topic. Unless you load a diesel up, running them in gear, you will glaze the cylinders and fill the crankcase with moisture, neither of which result in longevity.

Start your engine, let it run long enough to be happy it will keep running, then put it in gear and bog off. 1000 rpm for warmup is best but warm it up with a load. If you are leaving a complex harbour you will likely not get 1000 but its better than idling at any speed.

Running them at idle with no load is bad news except for the rebuilders.

If you are worried about the oil draining, disconnect the fuel solenoid and spin the engine briefly with the starter to get oil pressure. Not too long or you get raw water issues. I do this when I haven’t started her in a while. Then reconnect the solenoid and she starts instantly with residual heat in the cylinders.
 
This from a recent and previous post;
I run my boat at the marina i maint. mode.
Open seacock.
Start and run dead idle several minutes.
Run several five or so minutes at 1100rpm.
Tighten up the spring line if needed, put in fwd gear and run for about 8-10 min at 1400rpm. Sometimes 15 to 20 min. Sometimes for a minute at WOT. That’s overloading the engine though because the boat is stationary.

Xbank,
I adjust my idle up a bit so if I back out of my slip and pass through neutral on my way to fwd gear the engine won’t quit.
 
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1400 tied to the dock? your not going to make friends doing that. just remember to duck when that cleat let's go.
 
Haha. This is my first yacht. So, I am more than apprehensive doing that. My Nabor's would be like"look at the rookie trying to bring the place down"��
 
My previous marina owner had just spent a couple hundred thousand dollars putting new pilings in. He requested that I don't back into my finger pier (against land) because of the potential damage it could do when I powered away from the dock.

If he would have seen anyone warming his engine in gear at 1,400 RPM, first he would have a heart attack then he would cut the line.

pete
 
Gentlemen, do a search here on this topic. Unless you load a diesel up, running them in gear, you will glaze the cylinders and fill the crankcase with moisture, neither of which result in longevity.

Start your engine, let it run long enough to be happy it will keep running, then put it in gear and bog off. 1000 rpm for warmup is best but warm it up with a load. If you are leaving a complex harbour you will likely not get 1000 but its better than idling at any speed.

Running them at idle with no load is bad news except for the rebuilders.

If you are worried about the oil draining, disconnect the fuel solenoid and spin the engine briefly with the starter to get oil pressure. Not too long or you get raw water issues. I do this when I haven’t started her in a while. Then reconnect the solenoid and she starts instantly with residual heat in the cylinders.

I concur with Xbank. Much has been written on this at boatdiesel.com and by Tony Athens, Cummins guru. For me, I change oil and filters in the fall and don't start them again till spring. No ill effects in many years doing this. Same drill on the genset. I do, however, turn on block heaters during cold weather to reduce moisture in the engines.
 
DrQ,
Idling a diesel, especially with no load, for "long" periods is definitely a bad idea. So for warm up, start the engine, untie the boat, and leave the dock. Takes about 3 minutes from start to leave. Warm up is continued "under load" at about 1000 rpm or less, until your engine temperature reaches above 120 degrees F. Gradually increase rpm as desired at that point staying below "cruising rpm" (80% WOT) until the engine reaches full temperature.

Coming back to the dock, in most cases you do not need to "cool down" the engine by idling in neutral at the dock as some do. In most situations, you will be operating at greatly reduced rpm when entering the marina, maneuvering into the slip, and finally securing the lines, thus already having "cooled the engine" by operating at a reduced rpm. Shut down as soon as the lines are secured. Also your neighbours will appreciate this. :)

If you are worried about longer periods where the boat will not be used, first, use the boat! :)
If not, at least "bump" the engine with the starter monthly to move the impeller so it does not "take a set" (or you could remove the impeller for storage). Alternately, you could run the engine with the boat tied to the dock as suggested by Xsbank, but run it in gear under load, at around 1000 rpm (after a very short idle period) but ensure that you have the boat well secured (assuming you don't have some very large boat), for about 30 minutes to ensure that the engine reaches operating temperatures while under load.
Before starting, always give the engine and room a good pre start check. Look for any signs of a problem, like leaks, disconnected wires, etc. Check the oil level in both engine and transmission. Check the coolant level, the fuel filter for signs of debris or water, the belt(s) for signs of wear and looseness, etc. Open the thru hull for cooling water and check the strainer to ensure it will allow for the free flow of water. Do any other pretrip preparations like turning on electronics, radio, disconnecting electrical power, looking around for potential problems like floatsum in the waterway, traffic, etc.

Start the engine, and check for water flow by looking into the strainer, feeling the raw water pump (it should be cool, not warm or worse yet hot), or watching for it's discharge if that is visible (my boat it is not visible). Cast off as described above.
Underway, keep an eye on your gauges to ensure adequate oil pressure, the alternator is working properly, and you are not overheating. Periodically check the engine visually and by listening to it (for strange new sounds).
I would suggest the installation of a raw water flow alarm to monitor the flow of cooling water. They are not expensive and it will let you know if you forgot to open the thru hull or somehow the seacock got blocked (plastic bag for example). I also suggest adding an oil pan heater to keep the engine warm and to help keep the ER dryer. Inexpensive and only use about 250 watts of power when plugged into shore power.
Like Ken, I change the oil in the fall, don't run my engine or gen set all winter. I store them with freshwater and "salt away" in the raw water cooling system, I run my oil pan heater, and I bump the engines monthly with the starter to avoid allowing a set in the impellers. Never had a problem.
 
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My practice: start engine, check water outflow, immediately cast off dock lines, run 800-1000 RPM through marina, run at 1400 RPM upon leaving marina, increase RPM (1800 for me) to achieve cruising speed once engine has reached normal operating temperature.
 
Thank you so much. You have been tremendous helpful. I live in Florida and onboard so not winters for me. I will take your suggestions. Thank you again
 
Thank you so much. You have been tremendous helpful. I live in Florida and onboard so not winters for me. I will take your suggestions. Thank you again

Just take her for a ride - what better excuse for a boat ride... It's required PM:)
 
Everything is a tradeoff. I started my engines today (QSM 11s), idling them at 1000 rpm (no load); they got up to operating temp (or at least the oil and coolant did) within about 5 minutes. I am very skeptical that a modern engine would be "damaged" by glazing under those circumstances. I think it is better to get the impellers moving and oil circulating. I also started both gensets and got them up to temp for the same reasons. No smoke from any engine.
 
Tony Athens, over at Seaboard Marine, who is considered to be a true "guru" of marine diesels, advises against idling of diesels (without load).
He has over 35 years experience, and is a sought after expert. I, for one, listen to him.
He has tons and tons of free info over on his "commercial" (in that he does sell services and parts) site sbmar.com both under "Tony's Tips" and in his free forums.
 
I suspect that if you were to ask Tony (with whom I have had many similar conversations over the past 15 years or so) how often a modern diesel engine should be started if it were to otherwise sit for months on end, he would at least hesitate while considering the pros and cons of starting vs. not. In the end, he would probably acknowledge that without real data, it is just a guess, and that once a month is as good a guess as any. He would probably volunteer that old two cycles are a different story, and that plenty of them get fired up after years, if not decades, of non-use, without any problem.
 
"Tighten up the spring line if needed, put in fwd gear and run for about 8-10 min at 1400rpm. Sometimes 15 to 20 min."

The hassle is this can move lots of bottom soil.

In over regulated areas this is frequently the marinas method of dredging .

Works well IF the dirt can be blown into a spot that doesn't block a channel or slip access.
 
I have seen engines damaged from extended sitting without being run. And repaired a bunch of them.

Idling at the dock at 1000rpm is not the greatest thing for an engine. It is much happier doing some work. But I think it is worse for it to sit for months in a humid environment without being run at all. Things like valves and liners corrode, seals adhere to shafts, etc. Good to run it ten minutes to get some heat into it and throw the oil around. No need to get to full temp, most engines that is not really possible without load.

Definitely best to leave the dock and let it eat, but there are some situations where that is not easy to do.

(and yes, if you prop dredge in my creek, you will be evicted!!)

On my personal boat I run the engine and gennie dockside about once a week even if boat goes nowhere. But I make up for it by taking it out at least once a month for a run under power. There was a period of like four months where it sat while I was living on it whiile building a dirt house, it got run dockside once a week or so then. Finally got to take it out and it definitely cooked some slobber out of the manifold, was stinky for a mile or so. But then all good.
 
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I think the real gist is don't overthink it. If you use your boat somewhat regularly, then everything will be fine....at least once a month maybe??? My point being if you use your boat once a month then there is no reason to run it in the slip at idle no load. Now if you never use your boat or only use it once or twice a year then maybe idling it no load might be better than it just sitting there. Tony Athens will always take the "it depends" approach. HIS point is that there is no reason to warm an engine up before going out. In fact, he recommends against it. He always says to get ready to leave, start it up, and get going....no need to idle to warm anything up....it does no good.
 
Second that about warming up before leaving. No point in that at all. Warm it up under some load.

On mine, hull speed is about 950rpm so that's what I run until temp is 185F. Once that is stable, I'll add power as desired. I don't advise going to high power setting until temp is stable. Takes my boat about a mile.
 
On mine, hull speed is about 950rpm so that's what I run until temp is 185F. Once that is stable, I'll add power as desired. I don't advise going to high power setting until temp is stable. Takes my boat about a mile.

One reminder method I heard some time ago was to multiply engine temp by 10 for a not-to-exceed RPM during warmup.
 
I tighten the lines, conduct a standard engine check, fire up the Lehman 120 and check for water out the exhaust. After a minute or two, I put it into forward and let it run in forward for a few minutes. As the temperature come up, I increase RPM gradually as if cruising until the temperature reaches 150 degrees at which point the engine is running 1700 RPM. I run it at 1700 for about 5 minutes, in forward, at a temperature of 185 degrees.

I start reducing RPM gradually so that the stretched lines will gently return the boat to it's docked position. I place the transmission into reverse for a minute or two and neutral.

I let the engine idle for a few minutes while I retie the lines and shut the engine off.
 
Start and run dead idle several minutes.
Run several five or so minutes at 1100rpm.
Tighten up the spring line if needed, put in fwd gear and run for about 8-10 min at 1400rpm. Sometimes 15 to 20 min. Sometimes for a minute at WOT. That’s overloading the engine though because the boat is stationary.

.

I can guarantee there would be scary breakages if we did that.
When we first got her we did it at 800rpm idle to check gearbox pressures.
Ropes were protesting the boats 150ft behind us were being buffeted around and we deepened the channel judging by the amount of mud churned, and we had 4ft under keel.

14 litre engine driving a 48 inch 4 blade prop inside a Kortz nozzle has some bollard pull

Never again.
 
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Twice a month I take my twin FL120’s for a 30 minute cruise then on my way back in stop at the pump out station for a quick unload. They run like champions and never need to pay for a pump out.
 
Does anyone have any suggestions about starting and warming up the engines.

Is this something you do weekly at the marina?

What do you do before starting, what to look for when running?

How long do you run the engines?

What other suggestions do you recommend?

Thank you in advance!!!

I have a system that has worked for me for about 60 years with numerous gas and diesel, turbo and NA cars, trucks, tractors, lawn mowers, airplanes and boats, including my current Cummins (turbo) diesel in my boat. When I need the engine I start it and when I'm through with it I shut it off. The end. My position is that more damage is caused by idling cold and fussing with it than just running it for the purpose intended. Same is true when departing a dock. I get all the lines loose but one and then start the engine, toss the line and leave. Bothers the neighbors a lot less. Works for me.
 
I have a Mainship with a Perkins diesel. Diesel mechanic will tell you to never crank it in the marina more frequently than once a month. To do so means that the fuel never burns adequately off and will crud up the engine causing eventual damage. It will not get hot enough in the marina to burn off the fuel. What I do is crank mine monthly while tied up and then put it in gear and run it 1100 rpm until it reaches 180 degrees or so. It takes about an hour for mine but when I'm done the blue smoke has turned to the normal light white smoke.
 
G'day,


Plenty mentioned on here about running the engines on load so wont go there..


Personally, I run up one engine, leave the engine bay open, check with torch for leaks, how the belts are running, coolent etc etc. Check for water pumping out the exhaust. Shut down and do the same on the other engine.



Running one engine at a time I can hear any noises or anomalies during start up..


I check gauges on both lower and upper helm.



We make a point to open close sea cocks when visiting the boat, and also spin the wheel turning the rudders. Maybe it makes a difference but there is time when the boat has sat for a while and maybe fouling could clog up around the steering ;)
 

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