Alternator Output on start up Mainship 400

[davidla]

According to my Victron BMV, my stock alternator does not put out any current for exactly four minutes after engine start. I cannot find any reference to this in the Yanmar manual (single yanmar 370hp).
Does anyone know if this is working by design or if I have a problem with the alternator?

 

[kchace]

I would say you have a problem. The only time I have seen an alternator do this is when it had worn out brushes. I suppose it could also be an electrical wiring issue.

Ken

 

[High Wire]

Is that at idle or throttled up?

 

[Comodave]

I think that some alternators don’t output while starting and until oil pressure comes up but 4 minutes does seem long. But maybe the manufacturer designed it that way. I would give them a call if you don’t see the information in the manual.

 

[Simi 60]

Putting charge into starts before putting it to house?

Need a dual battery relay
And if a big house bank expect smoke from alt soon

 

[Bacchus]

I would put a clamp on ammeter directly on the alt output and see what it's doing.
Do you have an isolator / combiner that splits amp output between start & house bank?

 

[davidla]

My Victron BMV 712 connects to start and house banks for monitoring. Neither moves in the first four minutes. After that both move thanks to the VSR. I assume the wiring is standard and the alt output goes back to the starter motor and thus back to the battery. This is what the yanmar manual indicates and I see no change in the factory wiring in that regard. The volt meter at the engine control panel agrees with what the BMV is reporting and it is connected directly to the alt. So probably no need for a clamp meter.
Maybe it’s oil pressure or temp controlled but the four minutes thing seems pretty precise. Will monitor and see if I can find any other clues.
Oh and it’s at start so idle but if I increase the revs a bit there is no change

 

[roberttigar]

On an alt with an external regulator, the regulator is programmed to delay charging for a period of time to give the engine time to warm up. 3-4 min sounds about right. Bob

 

[catalinajack]

According to my Victron BMV, my stock alternator does not put out any current for exactly four minutes after engine start. I cannot find any reference to this in the Yanmar manual (single yanmar 370hp).

Does anyone know if this is working by design or if I have a problem with the alternator?

If it is exactly four minutes, every time, that strongly suggests that the regulator is programmed to a four-minute start-up.

 

[Bacchus]

I'm no expert on this unit but the Victron manual lists a setting for charge detection time with a default setting of 3 Min and is settable in 1 min steps.

Just guessing that it samples both banks before deciding whether to connect or not. Surprised there isn't one primary bank that gets a charge immediately but I didn't read the complete manual. It's available online if you don't have one.

 

[rgano]

Don, given his comment about the voltmeter being connected directly to the alternator, could the Victron detection time be relevant here? I am drawn the an external regulator issue as the culprit.

 

[Jc180]

On an alt with an external regulator, the regulator is programmed to delay charging for a period of time to give the engine time to warm up. 3-4 min sounds about right. Bob

My Balmar with external regulator programmed this way.

 

[twistedtree]

I'm no expert on this unit but the Victron manual lists a setting for charge detection time with a default setting of 3 Min and is settable in 1 min steps.

Just guessing that it samples both banks before deciding whether to connect or not. Surprised there isn't one primary bank that gets a charge immediately but I didn't read the complete manual. It's available online if you don't have one.View attachment 141656

I think that’s just how the device decides the battery is fully charged. It should always meter correctly.

 

[twistedtree]

This sounds like a regulator that has a delay before charging starts. Is the alternator internally or externally regulated? With internal regulators I have seen the delay be much shorter, perhaps 30-60 seconds, but haven’t timed it. 4 minutes seems like a long time to me, but certainly plausible, and some say the Balmar default is 3 min.

 

[Bob Almes]

I'm sure your alternator is fine. The Yanmar engine has an air heater that kicks in on startup and stays on for three or four minutes. The heaters draw huge amperage until the relay turns them off. The voltmeter will show no charge until they turn off. I disconnected and removed mine years ago.

Bob

 

[rgano]

I'm sure your alternator is fine. The Yanmar engine has an air heater that kicks in on startup and stays on for three or four minutes. The heaters draw huge amperage until the relay turns them off. The voltmeter will show no charge until they turn off. I disconnected and removed mine years ago.

Bob

Before I removed those useless air heaters, the timers operated them no more than 40-50 seconds. 3-4 minutes seems like an exceedingly long time.

 

[Bacchus]

I'm sure your alternator is fine. The Yanmar engine has an air heater that kicks in on startup and stays on for three or four minutes. The heaters draw huge amperage until the relay turns them off. The voltmeter will show no charge until they turn off. I disconnected and removed mine years ago.



Bob

I believe those heaters only operate in cold temps. Don't recall what the temp is.
I pulled mine last year on a 15 YO Yanmar and they looked like new... that makes me believe they don't even kick in at initial start unless the temp is low enough, or they would have some discoloration.

 

[rgano]

I believe those heaters only operate in cold temps. Don't recall what the temp is.
I pulled mine last year on a 15 YO Yanmar and they looked like new... that makes me believe they don't even kick in at initial start unless the temp is low enough, or they would have some discoloration.

Before I removed them. mine certainly did not seem to care how hot it was outside.

 

[Bob Almes]

The air heaters on my 2005 Yanmar 6 cylinder stayed on for about 4 minutes drawing something like 50 or 60amps. When they turn off the voltmeter goes from about 12 volts to 13.5 /14 volts. Outside temperature has nothing to do with the amount of time they operate. The purpose of the heaters is to reduce visible smoke during warmup. I never really saw any difference with or without them. The dealer said it was fine to remove them. Yanmar actually made a blank plug to replace the heaters if you choose to remove them. Yanmar recommends replacing both of the heaters every 2 years. Last time I replaced them they had gotten expensive, so I decided to remove them. I never liked the electrical draw and the fact that if they fail, they can be ingested into the engine and destroy it.

 

[rgano]

The air heaters on my 2005 Yanmar 6 cylinder stayed on for about 4 minutes drawing something like 50 or 60amps. When they turn off the voltmeter goes from about 12 volts to 13.5 /14 volts. Outside temperature has nothing to do with the amount of time they operate. The purpose of the heaters is to reduce visible smoke during warmup. I never really saw any difference with or without them. The dealer said it was fine to remove them. Yanmar actually made a blank plug to replace the heaters if you choose to remove them. Yanmar recommends replacing both of the heaters every 2 years. Last time I replaced them they had gotten expensive, so I decided to remove them. I never liked the electrical draw and the fact that if they fail, they can be ingested into the engine and destroy it.

My experience and thoughts precisely! Dump the politically correct EPA junk on your Yanmar.

 

[twistedtree]

The air heaters on my 2005 Yanmar 6 cylinder stayed on for about 4 minutes drawing something like 50 or 60amps. When they turn off the voltmeter goes from about 12 volts to 13.5 /14 volts. Outside temperature has nothing to do with the amount of time they operate. The purpose of the heaters is to reduce visible smoke during warmup. I never really saw any difference with or without them. The dealer said it was fine to remove them. Yanmar actually made a blank plug to replace the heaters if you choose to remove them. Yanmar recommends replacing both of the heaters every 2 years. Last time I replaced them they had gotten expensive, so I decided to remove them. I never liked the electrical draw and the fact that if they fail, they can be ingested into the engine and destroy it.

That sure would explain the apparent delay in charging.

 

[Bacchus]

If delay is heater related it's easy to confirm clamp on A meter on Alt output and or heater input.

 

[twistedtree]

Aside from any EPA needs, I expect the intake heater will reduce engine smoke on startup and gas you and your neighbors out less than otherwise. Personally I welcome clean startups and warm ups, both on my boat on from my neighbors. I don't care for getting gassed out by a smoking cold diesel, charming as it may seem to some.

 

[rgano]

Aside from any EPA needs, I expect the intake heater will reduce engine smoke on startup and gas you and your neighbors out less than otherwise. Personally I welcome clean startups and warm ups, both on my boat on from my neighbors. I don't care for getting gassed out by a smoking cold diesel, charming as it may seem to some.

Well, that's not the case with the 6-cylinder Yanmars, with or without the heaters. Go ahead and ask me how I know.

 

[Bacchus]

My experience and thoughts precisely! Dump the politically correct EPA junk on your Yanmar.

Please elaborate on what EPA reqmts are applicable to trawlers?

 

[twistedtree]

Well, that's not the case with the 6-cylinder Yanmars, with or without the heaters. Go ahead and ask me how I know.

Good for the OP to know. I have no direct experience with the engine.

 

[jefndeb]

My 2006 400 started doing this same thing, as shown on the Farria gauges, after I replaced my stock alternator along with a Balmar AR5 external regulator, the delay was set to 60 seconds but it still shows 0 voltage for about 3-4 minutes and I have not been able to figure out why...

 

[rgano]

Please elaborate on what EPA reqmts are applicable to trawlers?

The EPA, as you probably know, sets no requirements for "trawlers" as such. The organization has everything to do with engine emission requirements, no matter what boat or engine. As an example, you cannot buy a new 6LPA-STP like mine as a replacement. A local friend is replacing his 6LPA-STP and had to accept a 6LPA-STP2 which meets EPA Tier II emission standards. Externally the engines are duplicates, but Yanmar tinkered with a few parts of this mechanically controlled engine to make it Tier II compliant. You have to look at the engine curves to see the slight differences. I would call it a distinction without a real difference. BTW, the advantage to him in buying it through Mastry was that apparently the EPA controls imports of these engines and Mastry handles all the legal paperwork mumbojumbo. You apparently cannot purchase one unless you already own and are replacing one. We were considering tearing a lot of parts off the old carcass to serve as a spares chest for other friends who have the -STP version, but the requirements for swapping out are that the engine returned must have ALL of its parts so that it can be "decommissioned."

So that's the EPA impact on "trawlers."

 

[Bacchus]

"The EPA, as you probably know, sets no requirements for "trawlers" as such. The organization has everything to do with engine emission requirements, no matter what boat or engine. As an example, you cannot buy a new 6LPA-STP like mine as a replacement. "

Rich
I appreciate the response and admit I know little about engine compliance vs compliance in use. I'm guessing a compliant Yan engine would not be compliant for OTR truck use... maybe OK for off road use?
IMO calling the preheaters as EPA required is a stretch in that Yanmar installed them before EPA compliance was necessary. To me, that says their purpose goes beyond EPA.
I guess we are both splitting hairs and not a big deal.

 

[twistedtree]

A pre-heater is typically a starting aid and provides cleaner initial running of a cold engine. I don't know if the EPA regulates that or not, but it sure can be nice for the operator and all those around. But it sounds like it doesn't make much difference when used on a boat that's always operated in warmer climates.