This may sound daft - but its a serious problem ... two 20Ah Lawn Tractor batterys

Refueler said:
Dunno ... she's a 43HP 4-107 .... basically a London Taxi engine ...

There wouldn't be a problem if motors like this still had starter handles ! The alternator will not be energised so won't care about no battery ... its only if you disconnect when alternators outputting that diodes etc. blow.

I put one battery in ... and I'll wait a bit ... pumps catered for now. We have weather forecast of + temps for rest of week.

Once my moneys released from arrest in Canada and I can draw on it again ... I'll fix everything.
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The 12v batteries on my ride-on mowers are 330CCA, and two of those in parallel should easily start your Perkins engine. Is there a CCA rating on your batteries?
 
Now this prompts a question ...

A Jump Starter as I have - is based on a 12V SLA battery ... not a flooded Lead Acid job.

So if you start your engine with the Jump Starter such as my Perky without a Lead Acid battery in the system - would the alternator be too much for the Jump Starter - because you would not be able to disconnect it - otherwise you risk blowing the alternator diodes ?

I only replaced the diodes beginning this year !!
 
Refueler said:
Now this prompts a question ...

A Jump Starter as I have - is based on a 12V SLA battery ... not a flooded Lead Acid job.

So if you start your engine with the Jump Starter such as my Perky without a Lead Acid battery in the system - would the alternator be too much for the Jump Starter - because you would not be able to disconnect it - otherwise you risk blowing the alternator diodes ?

I only replaced the diodes beginning this year !!
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I think if the jump starter can chuck out tens of amps to start the engine, it can probably cope with some current from the alternator without the volts going anywhere which will damage any diodes.
The exception to this might be if the jump starter has a diode in its output to prevent charging from the alternator.
I wonder if Lithium jump packs might conceivably be like this?
RTFM I suppose.
 
lw395 said:
I think if the jump starter can chuck out tens of amps to start the engine, it can probably cope with some current from the alternator without the volts going anywhere which will damage any diodes.
The exception to this might be if the jump starter has a diode in its output to prevent charging from the alternator.
I wonder if Lithium jump packs might conceivably be like this?
RTFM I suppose.
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I use Lithium packs daily in RC models ... they are amazing batterys ... but need care in use.

Guy I know was all overjoyed he'd bought one of those miracle Lithium based starter packs ... so we tried it. It turned the engine over for about 1 second !! Which I have to say did not surprise us. How can you get the Ahr's into such a small jump pack to turn an engine over enough ? and the amp load ?? A LiPo max amp load is based on capacity in A/Hr x C rate.
 
Refueler said:
Now this prompts a question ...

A Jump Starter as I have - is based on a 12V SLA battery ... not a flooded Lead Acid job.

So if you start your engine with the Jump Starter such as my Perky without a Lead Acid battery in the system - would the alternator be too much for the Jump Starter - because you would not be able to disconnect it - otherwise you risk blowing the alternator diodes ?

I only replaced the diodes beginning this year !!
Click to expand...

I think these things have pretty good protections built in - certainly will prevent connecting it the wrong way round and probably over-current too.

It is possible that they won't even work if there is not a battery in the circuit as the reverse polarity protection might not allow it to switch on.

Like you I have used these batteries in RC applications and they are amazing - run down from full charge to flat in 10 minutes then recharge and keep coming back for more. That is why I have a lot of confidence in them as a back up starting battery
 
It only takes about 1ahr to start a marine diesel engine (assuming it's in good nick and doesn't need lengthy churning) however, the Perkins may have glowplugs so maybe a bit more.
 
ghostlymoron said:
It only takes about 1ahr to start a marine diesel engine (assuming it's in good nick and doesn't need lengthy churning) however, the Perkins may have glowplugs so maybe a bit more.
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Fine ... but its the Amps that is the killer ... I have suspicion that those two batterys even together are going to suffer trying to deliver wopping amps ... regardless of total A/hr used.

My Perkins has the old diesel drip feed into air intake .... via a Glow Plug that ignites it ... so a flame gets sucked in. I looked into the history of it and it appears to be from the days of early tank engines.
The thing is - it works every time ! If I remember to top up the small tube reservoir. So usually I end up using the Easystart.
 
Refueler said:
Fine ... but its the Amps that is the killer ... I have suspicion that those two batterys even together are going to suffer trying to deliver wopping amps ... regardless of total A/hr used.

My Perkins has the old diesel drip feed into air intake .... via a Glow Plug that ignites it ... so a flame gets sucked in. I looked into the history of it and it appears to be from the days of early tank engines.
The thing is - it works every time ! If I remember to top up the small tube reservoir. So usually I end up using the Easystart.
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Good way to kill an engine.
 
Refueler said:
I use Lithium packs daily in RC models ... they are amazing batterys ... but need care in use.

Guy I know was all overjoyed he'd bought one of those miracle Lithium based starter packs ... so we tried it. It turned the engine over for about 1 second !! Which I have to say did not surprise us. How can you get the Ahr's into such a small jump pack to turn an engine over enough ? and the amp load ?? A LiPo max amp load is based on capacity in A/Hr x C rate.
Click to expand...

A while back I looked at some used cars. All car dealers seem to have these Lithium jump packs now. I was more impressed with the jump pack than the used cars.
I could have bought a Litium battery for my bike, that would be about 5Ah and rated for at least 200A of starting, probably more.
A jump pack with normally get some assistance from the vehicle battery being in circuit, even if it's only acting as a big capacitor.

Lithium motorbike batteries seen to be getting down towards Lead-acid prices, but the known makes with circuitry in to protect the battery from the bike's charging circuit are still something of a premium.
 
Not sure why your local scrappies won't sell you a car battery. I got a really good one for £10 from our local scrappy a few weeks ago. They had all the good ones laid out for sale on a big workbench (north Sussex).

On the matter of possibly blowing alternator diodes when using a lithium jumpstarter - if you put one of the tractor batteries in circuit at the same time, the problem doesn't arise.
 
lw395 said:
A while back I looked at some used cars. All car dealers seem to have these Lithium jump packs now. I was more impressed with the jump pack than the used cars.
I could have bought a Litium battery for my bike, that would be about 5Ah and rated for at least 200A of starting, probably more.
A jump pack with normally get some assistance from the vehicle battery being in circuit, even if it's only acting as a big capacitor.

Lithium motorbike batteries seen to be getting down towards Lead-acid prices, but the known makes with circuitry in to protect the battery from the bike's charging circuit are still something of a premium.
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My Son keeps his motorbike in our garage in winter so I decided to put his battery on charge last week.

I took off the removable rear part of seat and it's not under there.

I unbolted the entire seat frame and removed the whole lot and it's not under there.

I got a torch and searched the entire bike. No sign of any battery.

I finally resorted to the last refuge of the scoundrel and discovered dozens of links asking exactly the same question.

The answer is that it's under the petrol tank and the whole lot including all the trim panels has to come off. Probably a couple of hours work.

It's not going to be charged. :ambivalence:

Richard
 
Refueler said:
Fine ... but its the Amps that is the killer ... I have suspicion that those two batterys even together are going to suffer trying to deliver wopping amps ... regardless of total A/hr used.

My Perkins has the old diesel drip feed into air intake .... via a Glow Plug that ignites it ... so a flame gets sucked in. I looked into the history of it and it appears to be from the days of early tank engines.
The thing is - it works every time ! If I remember to top up the small tube reservoir. So usually I end up using the Easystart.
Click to expand...

You are lucky that you have been getting away with this without doing serious damage to the engine.

Easy start is OK for petrol engines because the ignition still relies on the spark and therefore occurs at the right time in the cycle

However with diesel engines, which rely on compression raising the temperature of the fuel air mixture to the point at which ignition occurs, you have no control of the time in the cycle at which the Easy start ignites.
It may well ignite well before the piston reaches the top of the compression stroke then you have a situation in which the "explosion" occurs and tries to force the piston down while it is still being driven upwards by the cranking process.
This can result in physical damage to the pistons , con rods etc

If Stu Davies (skipper_stu aka heckler) comes this way he will tell you more.


However returning to your immediate concern, namely flushing the cooling system with antifreeze with no means of starting the engine to pump it through.

I deduce that your engine must be directly seawater cooled ??

Can you not completely drain it and then fill with diluted antifreeze via the thermostat housing,? Taking care, of course, not to over do it and flood the cylinders via the exhaust system
 
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