Warm up 120HP lehman

[Eli27]

Hello all. What is the average full warm up time on a 120 lehman. Ambient temp is about 70.

Now I'm not asking to the second. More like 8-10 minutes or about 15min or 5??

Also, on the velvet drive transmissions,, checking the fluid. Do you check that cold or warm? Engine running or off? I just did a completes service to it,,, fluid, cooler lines, and cooler. About a 1.5 quarts came out. I put in 1.75 to start. I figured the cooler and brand new lines (oversized per AD) being dry id add a touch more.

Thanks

 

[Comodave]

Warm up time depends on how the engine is loaded. If you idle it the engine will take a very long time to warm up. If you load it maybe only minutes.

 

[psneeld]

Zero warm up time unless you are the rare one that is out of slip and in a high speed area and use more than 2000 rpm in just a few minutes.

Usually just high idling under load and gradual increase in speed till the channel is fine.

If at anchor, high idling out of the anchorage is good enough.

This all assumes a trawler type boat where you are just using a fraction of max power even when cruising.

Again, if your Lehman is in a higher speed boat and you get on the engine at cruise speed, then just wait till up to 180 degrees engine coolant or so before significantly increasing RPM.

 

[Eli27]

Zero warm up time unless you are the rare one that is out of slip and in a high speed area and use more than 2000 rpm in just a few minutes.

Usually just high idling under load and gradual increase in speed till the channel is fine.

If at anchor, high idling out of the anchorage is good enough.

This all assumes a trawler type boat where you are just using a fraction of max power even when cruising.

Again, if your Lehman is in a higher speed boat and you get on the engine at cruise speed, then just wait till up to 180 degrees engine coolant or so before significantly increasing RPM.

Good to know. Any idea on the gear fluid level check? It's a velvet drive. It does have a distinct to check level.

 

[DavidM]

Warm up time depends on how the engine is loaded. If you idle it the engine will take a very long time to warm up. If you load it maybe only minutes.

On my Yanmar 370, a similar displacement engine, it would take 15-20 minutes for the engine temp to get to 180 at idle in neutral, but 5 minutes under load at 1,300-1,500 rpm.

I recall Tony Athens words of wisdom on this topic. He said, roughly speaking, start the engine and remove the dock lines and back out of the slip all without stopping. Then run it at a fast idle in gear until it hits normal temps. Then go for it!

David

 

[psneeld]

Good to know. Any idea on the gear fluid level check? It's a velvet drive. It does have a distinct to check level.

Pretty sure they manual I had said right after shutdown....as quick as possible do the check.... not sure why, may have something to do with drain back from the oil cooler.

 

[Max1]

I start my engine and let it idle while I do my pre-departure checklist. It usually takes me about 5 minutes. I don't engage the drive until the engine temperature opens the thermostat and the engine temperature gage starts to move. Then its a slow idle as we exit the marina (or anchorage; there are usually other boats anchored around us and we respect the other boaters right to no-wake). By the time we are clear the engine temp is up and we can go to cruise RPM

 

[SteveK]

Pretty sure they manual I had said right after shutdown....as quick as possible do the check.... not sure why, may have something to do with drain back from the oil cooler.

I agree, manual says at operating temp too.
Hot oil expands and after shut off drains back from cooler. Checking like this avoids overfill.

 

[boomerang]

After figuring out the correct level of oil after shutdown, I made a reference of the velvet drive oil level on the stick when it's cold, which always indicates overfilled when the oil has drained down. That way, I can check it, while making all of the other routine fluid checks , in the morning when it's not hot an oven in the engine room.

 

[rslifkin]

I've also noted the normal cold level on my Velvet Drives after confirming the level is correct by the recommended method (check hot and as fast as you can after engine shutdown). The cold level reading is always consistent in my experience, so once you know it's correct, then you're fine to check them cold.

 

[jleonard]

I untie and unhook everything at the dock except one line. Then I start the engine and get out of the slip and into the river at about 7 to 800 rpm to head out of the channel.
Once the engine reaches 140 F I can increase the rpm to whaever is desired. 140 F is warm enough.
I do this with my diesel truck as well.

 

[Pete Meisinger]

I don't think my F.L. needs it but I give it about 4 or 5 minutes while I coil the power cord, loosen dock lines and check water output from the engine.

pete

 

[rslifkin]

For pre-departure warmup, unless it's really cold, generally with just about any boat engine, I pull the shore power, fire up the engine(s) and raise to high idle. Start removing dock lines. When I'm down to the final couple of lines, return engine(s) to idle, confirm a stable idle (and with my gassers I usually want to see the temp gauges starting to come off the pegs at this point), then drop the last lines and depart. Most boats are plenty warm for heavier load by the time you get out of a no wake zone, etc.

I've never understood the people who feel the need to let their engine(s) warm up for 10+ minutes before leaving the dock. I see it some with powerboaters (want to see full temp before departing), but I see it quite a bit with some sailors (not all of them of course) where they crank up the engine as soon as they think about departing, then spend 15+ minutes removing sail covers, coiling shore power cords, etc. before actually leaving.

 

[psneeld]

After figuring out the correct level of oil after shutdown, I made a reference of the velvet drive oil level on the stick when it's cold, which always indicates overfilled when the oil has drained down. That way, I can check it, while making all of the other routine fluid checks , in the morning when it's not hot an oven in the engine room.

I usually did the same...but I just kept the high level in the back of my head. Think it was about a 1/4 inch higher than the top mark.

 

[Nomad Willy]

Start at 900rpm and increase in steps as you go toward your destination. Should take at least 15 minutes before you go to cruise rpm.

Cool down about 5 minutes at idle.

Adjust idle rpm to be just high enough that the engine will not ever quit when you back out of your slip and go through neutral to fwd gear. And just high enough for good smoothness that never inclines you to adjust it lower. Ideally that would be running smooth. Try to think of what will be best for the engine. Rough chuggy running is almost certainly not best for the engine. Especially for gears .. camshaft and other gear related moving parts. Gears could “clatter” back and forth .. so to speak.
Most skippers set idle too low for a tug boat like sound. That’s not to benefit the engine or other mechanicals. Low idle may also cause sooty injectors. I don’t really know about that tho.

When I was learning how to drive 18 wheel trucks my guide man told me to just let it “low idle” and “chug” (not smooth at all). Always wondered about that. It may be linked to “run at a speed that warms slowly” (frequently commercial situations don’t allow warm up). Whatever you do, do what’s best for the engine. And an engine rep. for your brand of engine should produce good practice. Not so much the mechanic at hand.

 

[Nomad Willy]

rslifkin wrote:
“where they crank up the engine as soon as they think about departing, then spend 15+ minutes removing sail covers, coiling shore power cords, etc. before actually leaving.”

IMO they probably just don’t realize how much time they take .. time flies when you’re busy. And their engine is not as important as on a powerboat. Most of us power boaters are at least somewhat mechanical to serious gearheads.

 

[rslifkin]

rslifkin wrote:
“where they crank up the engine as soon as they think about departing, then spend 15+ minutes removing sail covers, coiling shore power cords, etc. before actually leaving.”

IMO they probably just don’t realize how much time they take .. time flies when you’re busy. And their engine is not as important as on a powerboat. Most of us power boaters are at least somewhat mechanical to serious gearheads.

That's quite possible. I've always figured it comes from the typical sailor not trusting their engine, so they figure the longer it's running, the better chance it'll stay running. Of course, that distrust leads to reduced engine use and also poor maintenance (because they don't want to deal with the thing), so then it becomes less reliable and they trust it less, etc.

 

[Moonfish]

I've always started our FL120s and idled them at 900rpm while we check flow, pull the power cord, and untie the lines. Probably around 5 mins or so (unless our neighbors are there and we get to talking...). Then down to 700 for departing the slip. A minute or so later, once in the bay, back up to 900 for a couple mins while my wife pulls the fenders and coils the lines. Then up to 1300 to steam out of the bay for a couple mins, then to 1420 for our "cruising speed" the rest of the way. By that time, the operating temps are normal.

Those rpms we use are also the smoothest, least vibrating rpms. It's interesting, as 700-900 or so is smooth, but 950-1250 causes slight vibration. Under 600 just doesn't sound/feel smooth, either. 1300 and up is super smooth. All that is while in gear, and it's not so much the physical vibration which we don't like, it's the little buzzing noises of things vibrating that crop up all over the boat that bugs us!

 

[SteveK]

Warm up, no, not on purpose. After storing power line and removing all but two dock lines which are looped back to boat I start the engine. When at helm, the crew releases dock lines and away we go. RPM becomes high idle after leaving the fairway. And we are off. At some point the engine comes to operating temp.

 

[Delta Riverat]

My engines idle smooth cold at 750 so that's what I set for after starting. Warm they are smooth at 650 which is minimum speed. Never had a problem with putting in gear at any temperature.

I don't have a "warm up" routine either. Start, set speed at 750, check for water, undo the lines and power and back out, turn and head down the river. By the time I get out of the no wake zone it's been 15 minutes easy.

 

[psneeld]

That's quite possible. I've always figured it comes from the typical sailor not trusting their engine, so they figure the longer it's running, the better chance it'll stay running. Of course, that distrust leads to reduced engine use and also poor maintenance (because they don't want to deal with the thing), so then it becomes less reliable and they trust it less, etc.

My opinion with all my sailing friends as examples...they don't care about idling or wasted hrs on the engine.... they only have 500 or less hours on a 20 year old engine that will easily get to 5000 as long as they run it a few hrs every month or so and store it properly if they have to.

 

[whistlerxc]

Always wondered about this topic!

As is somewhat common to the forum the answers to the OP's question are varied but there seems to be a lot of consistency in not starting the engine (trawler diesel) until pretty well ready to cast off. This has been my practice. I do not have a FL but have a similar engine (Perkins). However I have generally waited until full operating temperature to go to full cruise RPM. This can take up to 15 minutes. But I have noticed many other boaters, including our local water taxi operator go to full or next to full rpm soon after leaving the marina/anchorage.

After reading the responses in this thread I wonder if I am being too conservative and can start revving up my rpms well before my 180F temperature is reached? Or at least gradually raise the rpms as soon as I am clear of the no wake zone.

I do sometimes feel silly as I creep towards my destination at idle for much longer than my fellow travellers!

 

[psneeld]

I think it really depends on what someone calls "cruise RPM"....

For someone like me using maybe 40hp out of 120 to cruise.... getting there within minutes after starting was never a big deal.

If going to 80-90% power at cruise speed a little different.

I believe many manuals say "do not use full power until up to operating temp".....

Look at how many people start their cars and pull out onto a busy street and mash the accelerator within a couple minutes of starting. And still get a couple 100,000 miless outof that engine.

 

[rslifkin]

I think it really depends on what someone calls "cruise RPM"....

For someone like me using maybe 40hp out of 120 to cruise.... getting there within minutes after starting was never a big deal.

If going to 80-90% power at cruise speed a little different.

I believe many manuals say "do not use full power until up to operating temp".....

Look at how many people start their cars and pull out onto a busy street and mash the accelerator within a couple minutes of starting. And still get a couple 100,000 miless outof that engine.

Agreed. I've got no reservations about running up to slow cruise power pretty much right away. That's about 1300 RPM for us with engines that turn a little over 4000 RPM at WOT. And probably putting out less than 10% of rated power. I won't run the boat up on plane until the engines are good and warm (a couple minutes after reaching full coolant temp) though, as that's a much higher power demand (fast cruise is ~3200 RPM).

 

[High Wire]

I have a Perkins 6.354 but it's the same drill. No extended warmup unless necessary for some maint item. Just idle enough to verify water flow out the exhaust then cast off lines. Warm up in gear is preferred IAW diesel mechanics that I've talked to. Wait until coolant temp >150F before coming up to cruise speed.

 

[boomerang]

Worth mentioning, it's a common practice to fire up a generator from dead cold and throw it online immediately, without even considering a warmup. Lots of backup generators do just this and they go merrily on their way. Would they last longer with a warmup. Maybe. Maybe not. I maintain the electronics on a fleet of fishing ships & every day, the generators, refrigeration compressors & fish pumps (mostly John Deere nowadays) get cold-started and put under load instantly. The few failures that have occurred were mostly turbos. We have a couple of naturally asperated 6-71's ,some set at 1400 & some 1800 RPM and they're pretty much bulletproof. From 0-1800 & put under load, all cold and in less than 30 seconds. Thousands and thousands of hours with no warmups and still going strong.

 

[Mambo42]

Worth mentioning, it's a common practice to fire up a generator from dead cold and throw it online immediately, without even considering a warmup. Lots of backup generators do just this and they go merrily on their way. Would they last longer with a warmup. Maybe. Maybe not. I maintain the electronics on a fleet of fishing ships & every day, the generators, refrigeration compressors & fish pumps (mostly John Deere nowadays) get cold-started and put under load instantly. The few failures that have occurred were mostly turbos. We have a couple of naturally asperated 6-71's ,some set at 1400 & some 1800 RPM and they're pretty much bulletproof. From 0-1800 & put under load, all cold and in less than 30 seconds. Thousands and thousands of hours with no warmups and still going strong.

A generator usually runs at 1 specific RPM, 1500 most of the time, and whether you put a load on it or not, that is not going to change. The engine of a generator is usually a lot thinner than a heavy engine like a Ford Lehman and that is where the problem starts.
If you fire up a Ford Lehman and instantly take it to higher RPM's you get spot temperatures in the block that can cause stresses in the metal which you don't want.
Therefore I fire up the engines, let them come to temperature slowly and only then will I start manoeuvring. After I come back in port I let the engine cool down from the last bit of manoeuvring for about 5 to 10 min to get the even temperature back into the block. Only then do I shut it down.
This may seem to be all a bit too much, but it is what I have been taught by some old diesel mechanics. Diesel engines like to run for long periods at a time at 1 rpm setting and don't like powerbursts where you create spot temperatures in the block which don't benefit the lifecycle of the engine.

 

[psneeld]

A generator usually runs at 1 specific RPM, 1500 most of the time, and whether you put a load on it or not, that is not going to change. The engine of a generator is usually a lot thinner than a heavy engine like a Ford Lehman and that is where the problem starts.
If you fire up a Ford Lehman and instantly take it to higher RPM's you get spot temperatures in the block that can cause stresses in the metal which you don't want.
Therefore I fire up the engines, let them come to temperature slowly and only then will I start manoeuvring. After I come back in port I let the engine cool down from the last bit of manoeuvring for about 5 to 10 min to get the even temperature back into the block. Only then do I shut it down.
This may seem to be all a bit too much, but it is what I have been taught by some old diesel mechanics. Diesel engines like to run for long periods at a time at 1 rpm setting and don't like powerbursts where you create spot temperatures in the block which don't benefit the lifecycle of the engine.

Again, unless specifying a particular load and what exactly are "higher RPMs" whether seconds or 15 minutes warmup really is just a matter of guessing/opinion/difference/whatever.

If anyone here owns a Taiwan Trawler or old Grand Banks with Lehmans, you can prep for underway....start your engine....unplug and toss off lines...get underway to the channel and come up to typical 6-8 knot cruising speed and never worry.

I did it for 10 years, 20,000 miles, and 3500 or so hours and still had great oil analysis.

Caution is good, but warm up periods for engines run well under their max load for cruise speeds of your boat just isn't one of them.

 

[Marco Flamingo]

I don't engage the drive until the engine temperature opens the thermostat and the engine temperature gage starts to move.

I don't think that's how it works. When the engine temp is rising, it means that the thermostat hasn't yet opened. Temp rises until it reaches the thermostat set point (190 degrees in my case), at which point the thermostat opens (and closes), keeping the temp steady.

But I don't think that leaving the dock as the temp is rising is a big thing. I use the old wife's tale method (or whatever the boating equivalent is). Never exceed in RPMs 10 times the temperature in Fahrenheit. I start the engine and the temp reads below 100. So I keep my RPMs below 1000. That's what I need to back out of my slip anyway. By the time I'm out of the marina, temp is about 110, so I can go to 1,100 RPM in the no wake zone. By the time I'm out of the no wake zone, temp is at 150, so 1,500 RPM is okay.

It's biggest benefit is probably that it's easy to remember.

 

[jleonard]

I don't think that's how it works. When the engine temp is rising, it means that the thermostat hasn't yet opened. Temp rises until it reaches the thermostat set point (190 degrees in my case), at which point the thermostat opens (and closes), keeping the temp steady.

But I don't think that leaving the dock as the temp is rising is a big thing. I use the old wife's tale method (or whatever the boating equivalent is). Never exceed in RPMs 10 times the temperature in Fahrenheit. I start the engine and the temp reads below 100. So I keep my RPMs below 1000. That's what I need to back out of my slip anyway. By the time I'm out of the marina, temp is about 110, so I can go to 1,100 RPM in the no wake zone. By the time I'm out of the no wake zone, temp is at 150, so 1,500 RPM is okay.

It's biggest benefit is probably that it's easy to remember.

So,using your theory, you shouldn't run at 2200 until the coolant temperature reaches 220 F ?
Or not got to WOT until it reaches 240 F.
That doesn't make sense to me.