volvo edc

[Powersalt]

What with the **** winds on wednesday/ thursday I decided to stay in port but to run up the engines on the pontoon.

Pair of D6 430's and when I put it into neutral and attempt to rev either one will only go up to about 1500 revs and then seems held back by a limiter. So my question is is it rught not to be alble to rev the enginesout of gear above 1,500 revs ?
Never tried this before so have no history as to if I have a problem or not

 

[Moody]

That's Normal

Yes that's perfectly normal. You can only free rev to 1500 rpm. I think a Volvo engineer with a Vodia tool can override this.

Neil

 

[Powersalt]

thanks for the reply. I was just getting ready with my cheque book again, thinking things were wrong.
Cheers

 

[aquatom]

I'm not convinced that running the engine off load is a great idea. It can result in glazed cylinders and cause more damage than good! I would always let the engines warm up before giving anything near full throttle but do so gradually whilst leaving the port.

That's just my opinion. I would be interested to hear others....

 

[Bassplayer]

I'm not convinced that running the engine off load is a great idea. It can result in glazed cylinders and cause more damage than good! I would always let the engines warm up before giving anything near full throttle but do so gradually whilst leaving the port.

That's just my opinion. I would be interested to hear others....

Absolutely 100% right.

The number of people in our marina who run up their engines for 20 mins or so on a regular basis is amazing. It is very harmfull. Engines need to get the OIL hot enough to boil off the condensation. That takes a while.

So don't start the engines unless you are either going out or need to check something......

 

[Powersalt]

ok, good point. But now take the situation that your engines have not been started for 5 weeks and you down on the boat but not going out, say its the mid winter and rough outside the marina walls.
So do you leave them alone with the risk of oil leaving the cylinders or start up and run them on tickover in gear?

 

[Latestarter1]

I'm not convinced that running the engine off load is a great idea. It can result in glazed cylinders and cause more damage than good! I would always let the engines warm up before giving anything near full throttle but do so gradually whilst leaving the port.

That's just my opinion. I would be interested to hear others....

Absolutety no problem at all with some provisos you have mentioned.

Just to cover the point regarding electronic engines, manufacturers built in simple algorithim to prevent users running engines at high idle mainly for two reasons #1 was that governor droop is far tighter than on a mechanical engine often as little as 50 rpm and because of the nature of throttle control there is little one can learn from a high idle test. Another issue is the numpty factor performing a high idle test on a cold engine is plain dumb, no point in writing complex algorithim in order to check is engine has reach operating temperature you just limit no load idle to 1,500 rpm. Just the same as removing throttle control from the operator during cranking, just another anti numpty safety measure.

Going back to mechanical engines they are not the sensitive flowers that people on diesel engine courses try to kid you. ONCE THE THERMOSTAT is open you can pretty much rag the life out of diesel motor with zero ill effects.

New 'green' engines this time I am not referring specifically to Volvo here, go on automated 'hot test' freshly built motors go on robotic pallet, filled with hot water, started, run at idle, given the beans to test high idle, then go though load cycle. 6 minutes later engine is spat out of the test cell.

A high idle test does no harm on mechanical engine and provides important data as to correct setting of throttle controls and governor setting. Most marine engines are set to 10% governor droop For example motor with 3,000 rpm rated horsepower will rev to around 3,300 rpm high idle when out on the droop.

Amazing how people wince when you nail a nice warm engine and let it run on high idle test whilst taking readings off the gauges, engine is singing real nice tune to you whilst owners eyes sticking out like organ stops. Blipping throttles is just for Youtube videos.

The US Navy 500 hour test is pure evil, cycle consists of all of the above plus a full load cycle as well as a particularly nasty trick where cold water is pumped through the cooling system whilst motor is pulling peak torque on the dyno. After the test motor is stripped, any signs of component distress and you fail.

Lobster pots seem a hot topic, just think of this, fisherman runs out to fishing grounds for perhaps an hour or so, then commences to haul pots for say an hour, hydraulic PTO pump is adding little meaningful load on the engine which is sitting at idle, motor is then kicked into action again to the next string, and so the cycle goes on. I have seen skippers fall over making a dash for the kill switches the moment they have a line ashore to avoid deamon idling, cos thats what they were told on engine course.

I am not actively encouraging any of above practices, but niether are they the engine killers people make them out to be.

 

[SolentPhill]

I was told by my Volvo guy that the D4 do not like to idle, they told me not to run it unless making it work, same applies it must be fully warmed up before opening it up, but to sit on the mooring on tick over is not good

 

[Latestarter1]

I was told by my Volvo guy that the D4 do not like to idle, they told me not to run it unless making it work, same applies it must be fully warmed up before opening it up, but to sit on the mooring on tick over is not good

It is all a matter of degree. Not specific to motor type. However there are practical reasons where motor will idle for say half an hour, for example locking through French canals.

Yes better not to idle if you do not HAVE TO, however people become paranoid. On the subject warming up I know of few locations where engine has not had time to warm through and thermostat open on the way out, before you get the chance to nail that big chrome lever, and start ragging the nuts out of your motor.

Real promblems encountered are when engines subject to extended idling. I have experienced issues with rail operators over extended idling. Traditionally rail buses were always left idling in stations, sometimes for hours on end. Old BUT Leyland and AEC engines were always at risk of failing to re-start if shut down and screwing up time tables. We did not like approve at all particularly as the big Paxmans were always shut down on entering stations for fear of suffocating passengers, however drivers were set in their ways. So we put in programmable algorithim typically set to say 15 minutes, if left idling engine shut down automatically. Drivers then refused to drive the rail buses with this feature, claimed it was a safety issue????

In U.S. idling was a big problem, drivers would leave engine idling all night to keep cab warm/cold and lesser evil was engines being left to idle for hour or two whilst making a delivery. With the advent of electronic engines people could actually see how much fuel was being wasted in idle mode. Detroit Diesel even came out with electronic feature which fires up and shuts down engine dependant on climate control setting, kind of 12.6 liter cab heater.

As I said all a matter of degree, assuming correctly ventilated engine room, after a long passage with pedal to the boards a few minutes idling before shut down allows engine components to cool down nicely and everything to stabilise. It is the mad rush to hit the switches the very moment lines are ashore which makes little sense to me.