Starting a diesel with "dead" batteries

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foreverunderway

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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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Most boats have cross over switches to parallel batteries for emergency starting and if not, jumper cables.

And if not a small battery powered "Jump Starter" is an easier way to start an engine than taking the valve cover off, getting oil all over and trying to insert and remove coins.
 
Most boats have cross over switches to parallel batteries for emergency starting and if not, jumper cables.

And if not a small battery powered "Jump Starter" is an easier way to start an engine than taking the valve cover off, getting oil all over and trying to insert and remove coins.
I suppose if one had a genset or any other method to start the engine/genset then one wouldn't do this, would one? Duh.
 
Most boats have cross over switches to parallel batteries for emergency starting and if not, jumper cables.

And if not a small battery powered "Jump Starter" is an easier way to start an engine than taking the valve cover off, getting oil all over and trying to insert and remove coins.

Can't we just use a credit card with a chip? Who carries cash any more.
 
Years ago in a sailboat I had a single cyl Volvo with a very helpful decompression lever.
 
Gardners have a compression release lever for each cylinder. I recall starting a 6 cylinder by hand one day just to see if it could be done. Difficult for sure but we were younger and dumber, it was a lot of years ago. With a different boat I recall passing jumper cables out a porthole to another boat.

I think the trick with the dimes is just great. It's called "planning for the worst and hoping for the best".
 
Doesn't everyone?
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.
 
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.

Thanks,

Most of us are either experienced or smart enough to have redundant or back up systems for "worst case scenarios". And simpler solutions than to be running an engine with valve cover off and placing my fingers or pliers near rapidly moving machinery.

Sorry we didn't drop to our knees and praise your post and heap adulation.
 
Wow.

... wish I'd never posted this. ...

It is tips like yours that help make this forum so worth my time. Many members on this forum represent a great source of knowledge and some of us appreciate the generosity of you who pass it on. Especially little tid bits that are essentially lost to time.

Thanks for posting.
 
Can't we just use a credit card with a chip? Who carries cash any more.

Reminds me of an old story..... The original VW bug points, one could use a dime to get the "good enough" clearance in an emergency.
Okay, now the story.... could not fine a dime so he used 2 nickels, with the predicted results.... :dance:
 
It is tips like yours that help make this forum so worth my time. Many members on this forum represent a great source of knowledge and some of us appreciate the generosity of you who pass it on. Especially little tid bits that are essentially lost to time.

Thanks for posting.
Agreed:thumb:. Let`s ignore syjos.
 
I personally would not try the dimes with my V-8. It either starts from the batteries or it doesn't . I am very carefull about those starting batteries for that reason.

However, I for one, appreciate tips like that because who knows. If stranded I might. go that route. Even if one doesn't use a tip knowing it is a huge plus.
 
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, some things just sound bloody dangerous compared to simpler alternatives.

I would also think that someone who had the skills and knowledge to pull valve covers off etc etc etc would also be smart enough to have thought of a safe and easy backup to what is at the end of the day, a relatively easy fix.

Sorry if that sort of thinking upsets you.
It was not my intention.
 
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decompression

Thanks I will try and remember that, it is a great idea and when you are stuck you need these remedies to get you out of trouble
I used to have a boat with a two cylinder diesel that had a decompression lever but to crank it you had to use both hands so unable to operate the lever whilst cranking the problem was solved by tieing a rope between the lever and a handy cupboard door when up to speed I just kicked the door and it dropped the decompression lever and the engine would start
 
I would be concerned that by putting such a thick shim in place you may cause contact between the pistons and valves.
 
It's an interesting trick for sure. But between the inconvenience and risk of injury, I'd consider it a dire last resort. As in, only something to consider after exhausting all options for getting enough power to the engine (and if I can't manage that, either the boat's systems are deficient or multiple things have gone wrong). And even then, in many cases I'd rather wait for another boat to lend a hand with jumper cables or something.
 
To the admin, if this is in the wrong form, please move it to the proper forum.

** How to start the main engine from a dead start battery. ** "That is the question."

1. Start the generator from its own isolated battery and relax. The output will pass through the battery charger and charge the batteries.

2. Parallel the house batteries to the start batteries and relax.
Start the main engine.
When the start battery is above 11 volts separate the house/start batteries.... I think the Cummins needs at least 11 volt to keep its electronics powered enough to run the engine.
Watch the start battery to see if it will hold a charge. If not, replace at least the start battery. Yes, I know, it is recommended to replace the 4Ds together but.... if it is just the start battery... Replacing the house batteries should be done together.

Now, I have a question. 3 ways of charging the batteries via one battery charger.

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?

The broad question, am I correct???? Now, tearing the above thesis apart, which individual part is incorrect?
 
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It's an interesting concept, and one which would probably work but with my battery redundancy I'll never use it.

However, for whatever reason I have always been intrigued by the "spring starter" idea. Has anyone ever used one? Do they work?

pete
 
A dime is .053" thick. The exhaust valve clearance on my Perkins is around .012". The dime is 4 times too thick to fit in the gap. So you would have to force the gap/valve open with a wedge or back off the adjustment. Am I missing something?
 
I'm not going to promote the tip but there are places on this coast that people visit that they can be stranded in for a week or more if the engine doesn't start. SOmetimes no radio or cell service either depending upon how deep into the valleys they travel.

I would be very reluctant to consider that method but I also won't make fun of or deride it.
 
Anyway...
yes, thank you from those of us who appreciate knowledge. I'm pretty handy in the mechanical department but I've not heard of your decompression trick & it never hurts to have another ace up your sleeve should it be needed.
 
Some boats have electric starters on some engines and air starters on other engines, for redundancy, in case one power source fails. A small generator with a pull cord is an option too.

You never know when you might fall into a black hole or something, **** happens.


Good thread, thanks.
 
Thanks FF, what a neat video. If the spring starter were available for a F.L. and I was considering doing some remote cruising I might have one as a spare. Wonder what one would cost, probably not cheap, but then again a 12 volt starter for a F.L. runs about $500.00

I love this website, answers available for just about any question. Here is one for you FF. How did you accumulate 20,000 posts is a little over ten years? Thats like 5 posts a day.

pete
 
Dimes under rocker tips can do very bad things on some engines. On a four stroke at non-firing TDC the valves can be VERY close to the pistons. How close depends on which engine. Some are very close, some not so close.

Put dimes under rocker tips and you can have pistons hit and bend valves.
 
Dimes under rocker tips can do very bad things on some engines. On a four stroke at non-firing TDC the valves can be VERY close to the pistons. How close depends on which engine. Some are very close, some not so close.

Put dimes under rocker tips and you can have pistons hit and bend valves.
Thanks Ski...I would think on a rebuilt like mine where I have no idea if the head was shaved on the rebuild but definitely when I put a new head gasket on might be pretty critical.
 

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