Starting a diesel with "dead" batteries

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Early riser , not much to do before the sun comes up.
 
Start the genny and charge the batteries or use jumper cables from the genny battery

I am a diesel mechanic and I support this way to start a diesel engine. If you suggest a dime between a rocker and a valve stem... you may look for trouble that is greater that waiting to charge batteries. By suggesting using a dime... some will not have a dime and use some other things.... and by doing so you will create damage that will be beyond using you vessel for quite a while until you repair the damage you will have caused. It is not simply starting the engine... valves could be bent, pistons could be damaged, bearings could take a beating, and no one, and I mean no one can assure be that there will be NO damage.
 
Great Idea of starting if your battery is dead.
I use another solution, I just bought 2 the same boats, one towing the other, so if something like this happens I just jump to the other.
 
I was going through a locker on the boat full of "stuff" today, trying to clean out some of that junk we boaters collect as we go through life, and I found four US dimes (a 10 cent piece for those unfamiliar with the term dime), neatly wrapped and shiny new.
For those of you who do not have a compression release on your diesels (propulsion or genset) here is an old engineer's trick that may one day save your bacon.
When you find yourself with "dead" batteries, you should stop cranking immediately. Next, take off the valve cover and insert one thin dime (and only a dime if you do not want the possibility that the pistons will hit the valves) between the rocker arm and the exhaust valve stem. This will essentially release all compression and what power is left in your batteries should be able to turn the engine over fairly easily.
As the engine turns over, pull out one dime (in the proper firing order) using needle nose pliers and she should begin to run on that one cylinder, perhaps still requiring a bit of help from the starter. As you continue to remove dimes in the correct firing order, your engine should run on 2 or 3 cylinders well enough to get all the dimes out and be running on all cylinders.
Without a valve cover there is obviously going to be quite a bit of oil squirting out, but what's a bit of clean up compared to what could happen if you can't get your engine started?
I hope this will help at least one of you out one day.
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GOOD INFO, THANK YOU FOR SHARING. Knowledge can save lives....., and it did not hurt at all, nor did it cost me anything.
 
Wow.

It's folks like you who make me wish I'd never posted this.

Obviously, this site is a waste of my time 'cause you all got all the answers and so much experience you can't even imagine a worst case scenario.

Good luck with your boating.

Well I think it is a great bit of information to have in my mind should I ever be in a pinch and need to crank my diesel with a low battery.

Thanks!
M
 
I'm with Foreverunderway.

His critics are the ones who stand around in an emergency saying:
I'm not responsible for seeing this coming.
How could there be more that one failure at at time?
The tide and weather are responsible operate at my convenience.
It's not fair that this happened where I can't call for help.
Now it's your job to hurry up and bail me out. I have dinner reservations!

ARRRG that peeves me!
I would like to volunteer those kind of people to become eligible for a Darwin Award.

Better to consider how to deal with possible emergency's. It wouldn't be much of an emergency if timely help was available. Of course you would not rig a compression release if you could start any other engine and charge your batteries from that.

I would only add that I would start with the smallest engine, the genset, first and use that to charge the other batteries.

BTW A lot of the early hydraulic lifters were adjusted with the engine running and the valve covers off. It was not much of a mess.
 
No one has mentioned that after rigging a compression release you should first turn the engine over slowly by hand to check that nothing hits before you crank the starter.
 
Wow.

It's folks like you who make me wish I'd never posted this.

Obviously, this site is a waste of my time 'cause you all got all the answers and so much experience you can't even imagine a worst case scenario.

Good luck with your boating.

Agree,some people !!! Can see why I stay away from this forum mostly.
 
The dime trick is very useful should you be the victim of hydrolock. A fully charged battery and perfect starter cannot overcome this. Insert the dimes under the exhaust valves and you can turn the engine by hand until the water is expelled. Had this happen last year with the Dripless Shaft Seal cooling water backfeeding through the crossover hose to a non operating engine. Took me awhile to figure out where the water came from but there are now shut-off valves.
 
No one has mentioned that after rigging a compression release you should first turn the engine over slowly by hand to check that nothing hits before you crank the starter.

Back on the good intentions jist of this thread, thanks for another good idea Chris. That is the right thing to do to make the OPs idea a good and safe one when all else has failed! I also like this forum for the helpful nature of many posters with a can do attitude! Thanks!
 
Details:
We start with 4X4D batteries..... 3 house, 1 start. The generator battery is on its own.
1. main engine Standard alt..... I think about 150 amp. (Cummins QSB 5.9)
2. generator 6KW
3. solar This would take a very long time..... with 2X130 watt panels. They are to maintain or float on the battery system.

When underway, assuming the main engine alt has an output, the battery charger is unnecessary and should automatically be divorced from the charging system and it can be shut off. (40 amp charger)

As I understand it, the engine alternator directly charges the start and house batteries, bypassing the battery charger. This is standard and correct?
Most modern sources of charge (alternator, line charger, solar charge regulator) are well regulated devices. You can run them all in parallel, all will contribute what they can until the voltage set points have been reached.

Yes, on your AT and most any boat, the alternator operates independently of the line charger. However, like most any boat that has not been upgraded, the 150A rating of the automotive style alternator is a fantasy. The stock 19Si on an early QSB will *maybe* do 60A once it warms up (takes about 10 minutes or less). Even an externally regulated 28Si alternator will only do about 105A continuously.

The OPs shade tree compression release will depend a very great deal on the engine involved. An old mechanical diesel with one exhaust valve per cylinder, low oil delivery to the valve train, and sufficient piston/valve clearance it might not be too dramatic. Newer common rail 4 valve engine, high pressure oil in the valve box, it might be quite dramatic and involve significant engine damage. I would not try it on a lark without knowing a great deal about the specific engine.
 
Capo Doste, you were lucky you didn't bend a connecting rod. Radial airplane engines can hydrolock if enough oil seeps past the rings of the bottom cylinder while the engine sits. That is one reason you are supposed to hand prop an airplane engine before you try to start it. More than one person has spent a heck of a lot of money on what was until a second ago a perfectly good engine.
 
Great if you can reach them.

If you don't have enough juice in any of the batteries to start the genset how far will you reach with hand held radio?

Why not just run an extension cord to the marina? I assumed that were talking about situations where help was not forthcoming before things got worse?
 
Great if you can reach them.

If you don't have enough juice in any of the batteries to start the genset how far will you reach with hand held radio?

Why not just run an extension cord to the marina? I assumed that were talking about situations where help was not forthcoming before things got worse?

I am a bit confused ..... Isn't the generator battery isolated from all other batteries?
I know my generator start battery is isolated from all my other batteries and the onboard charger.
I do believe "you" are worried about a situation that cant happen.
 
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When my starting batteries are dead I wrap a rope around the pulley on the front of the engine and pull. It may work. LMAO
 
I think people are confusing 'are' with 'are supposed to be'. Look around you at all the things that are supposed to be until you find out they are not.

How often does anybody really verify the full isolation of the electrical subsystems of a boat? All the talk about electrolysis and stray currents proves to me that there are a lot of 'were supposed to be' electrical systems out there.

How isolated would the subsystems be during a wiring harness melt down. If you have controls and voltmeters for all the subsystems coming out to the cabin area that is a lot a wires to get right and keep right.
 
I hope you had your Wheaties before you try to had start at diesel engine over 3 HP without a compression release. They made and I think still make some respectable little diesels with compression release and only manual start. In some parts of the world men are still men.

Also be careful wrapping a rope around a motor shaft. If you have ever used one of the old loose rope pull start engines they had a very simple but effective rope release.

I could not find the video but supposedly some guys used a rope and a pickup truck to start a smaller antique diesel locomotive. Good news the engine started. Bad news the rope didn't come off. The truck got reeled back in and the hitch was ripped off. I am going to search again later for that video.
 
there are also the small lithium (?) rechargeable batteries to start auto engines. I suspect with a search, one can find one for a Cummins 380 or at least the generator start.
Battery chemistry sure has changed and improved in the last 5-10 years. But that's a topic for another forum.
 
Years ago I lived on a farm. The neighbor had 3 or 4 tractors that he would start by spinning the fly wheel. He had both tractors and stationary engine. A couple of tractors, he would start on gasoline and then with a twist of a valve, change it over to diesel fuel.
 
Since this thread has already "drifted" I don't feel bad about helping it "drift" some more.

The older I get, the weaker I get so I would never try to hand start my F.L. But, could any of you engineers tell me if it would be possible? 120 bhp, 6 cyl diesel.

I would guess the first thing would be to remove the belt driving alternator, pumps, etc.
My engine always starts in 20 seconds or less of cranking. Could one or two strong guys pull a rope fast and long enough?

pete
 
Years ago in a sailboat I had a single cyl Volvo with a very helpful decompression lever.
Engine also had a lever so you could rotate the flywheel, get it spinning, close the decompression lever, and it would start. Zero application to our big main engines, but still interesting.
 
Alternate methods of starting...
Gasoline engine, 80 hp. I've often used a hand crank on my car. Easy to do and a crowd quickly develops when you start setting up to do it in a public place. Two notable crowds were one at the pumps of a truck stop. Restaurant windows along the front very quickly filled with spectators in the few seconds it took. Another time on the ferry, big crowd real fast. Someone obviously recognized what was about to happen and said so to those nearby.
 
David, Very good tip, must admit I carry separate battery for genset starting.

:)
I was going through a locker on the boat full of "stuff" today, trying to clean out some of that junk we boaters collect as we go through life, and I found four US dimes (a 10 cent piece for those unfamiliar with the term dime), neatly wrapped and shiny new.
For those of you who do not have a compression release on your diesels (propulsion or genset) here is an old engineer's trick that may one day save your bacon.
When you find yourself with "dead" batteries, you should stop cranking immediately. Next, take off the valve cover and insert one thin dime (and only a dime if you do not want the possibility that the pistons will hit the valves) between the rocker arm and the exhaust valve stem. This will essentially release all compression and what power is left in your batteries should be able to turn the engine over fairly easily.
As the engine turns over, pull out one dime (in the proper firing order) using needle nose pliers and she should begin to run on that one cylinder, perhaps still requiring a bit of help from the starter. As you continue to remove dimes in the correct firing order, your engine should run on 2 or 3 cylinders well enough to get all the dimes out and be running on all cylinders.
Without a valve cover there is obviously going to be quite a bit of oil squirting out, but what's a bit of clean up compared to what could happen if you can't get your engine started?
I hope this will help at least one of you out one day.
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I have redundancy upon redundancy as far as my battery situation is concerned. I have an isolated battery for the windlass. Running a jumper or moving the battery would not be a big deal. Same for the battery on my genny. Then I have a spare battery not connected to anything, just sitting there all hot and ready to go. Then, believe it or not, I have a "jump pack" charged and ready to do its thing. For its size and weight it really packs a punch. It has a built in air pump which is really why I carry it. Mostly used for bike tires and floating toys.

I had a single engine gasser at one time. Also redundant in batteries. I used to say that if my engine failed I could probably make it back into port on my batteries and starter motor.

pete
 
I have redundancy upon redundancy as far as my battery situation is concerned. I have an isolated battery for the windlass. Running a jumper or moving the battery would not be a big deal. Same for the battery on my genny. Then I have a spare battery not connected to anything, just sitting there all hot and ready to go. Then, believe it or not, I have a "jump pack" charged and ready to do its thing. For its size and weight it really packs a punch. It has a built in air pump which is really why I carry it. Mostly used for bike tires and floating toys.

I had a single engine gasser at one time. Also redundant in batteries. I used to say that if my engine failed I could probably make it back into port on my batteries and starter motor.

pete

I'm in a similar situation as far as battery redundancy. Either engine or the generator can be started from either of my 2 start banks, selectable with a switch for each piece of equipment. And a pair of jumper cables allows starting from the house bank if needed. There's nothing powered from the start batteries except starter motors and the items controlled by the engine key switches (gauges, etc.).

So if I end up in a situation where all of those options are unable to get sufficient starting power to either engine or the generator, I've probably got a worse situation going on than just a lack of power.
 
Okay, if your main engine battery fails, you generator also fails, all your house batteries fail, you smoked the battery charger and the sun has not come out for the last month so your solar panels are useless.
It is time to rethink owning a boat. The goddess of all boats has decided, you are not worthy of owning a boat.
IMO, the probability of this all happening at the same time is less than one percent.
 
Hand cranking a trawler sized diesel engine without a compression release is likely not possible. Even with a compression release (would a dime under the rocker be enough?) it would be beyond the capability of most, if not all of us.
My own experience, on my 30'sailboat, was with a Yanmar YSE12, a single cylinder diesel WITH a compression release and a properly sized and fitted hand crank. There were a few occasions when I hand cranked that engine, successfully. I was in my 30s and very fit. I wouldn't dream of being capable of hand cranking even that small engine once getting into middle age and later, though I am still fit and weigh close to the same as I did in my 30s. An 80 to 200 hp diesel engine? Not a chance I would even dream of the possibility.
 
If you are concerned about all your batteries being dead when no outside assistance is available, get a portable jump starter.

Lot simpler and safer than PO's dime solution, which will not work with all engines due to valve to piston clearance.

.
 

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