Battery for starting VP MD1

ghostlymoron

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What size battery do I need for starting a Volvo Penta MD1 engine? The manual doesn't quote a CCA, I don't think that rating had been invented when the engine was made! The engine is about 400cc - medium sized bike engine. Don't bother quoting red flash batteries, I'm not made of money.
 

VicS

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The Workshop manual for the MD1 specifies 60Ah max
The recommended battery for the very slightly larger MD1B is 60 Ah max.

A 60Ah car battery would be a good choice and more than adequate I suggest!
Nobody seems to be able to explain why VP quote maximum capacities
 
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Plum

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What size battery do I need for starting a Volvo Penta MD1 engine? The manual doesn't quote a CCA, I don't think that rating had been invented when the engine was made! The engine is about 400cc - medium sized bike engine. Don't bother quoting red flash batteries, I'm not made of money.

The "cold cranking amps" CCA rating of a battery is more important than Ah capacity rating for engine starting. Better to have a 40Ah battery with a 450cca than a 60Ah battery with a 300cca.

Colin. Www.solocoastalsailing.co.uk
 

ripvan1

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Why is there a 60ah maximum - I've been using a 140ah varta and it starts within seconds, am I doing something wrong. While we're on MD1 I've found gasket sets from ASAP and Keypart but 1 set is twice price of the other - why is that. I can't find a thermostat housing gasket so suppose I'll need to make one unless anyone knows where I might find one.
 

bedouin

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Why is there a 60ah maximum - I've been using a 140ah varta and it starts within seconds, am I doing something wrong. While we're on MD1 I've found gasket sets from ASAP and Keypart but 1 set is twice price of the other - why is that. I can't find a thermostat housing gasket so suppose I'll need to make one unless anyone knows where I might find one.

Are you sure it has a gasket? On the MD2B there is a little rubber ring round one section but no gasket
 

Tranona

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The "cold cranking amps" CCA rating of a battery is more important than Ah capacity rating for engine starting. Better to have a 40Ah battery with a 450cca than a 60Ah battery with a 300cca.

Colin. Www.solocoastalsailing.co.uk

Car batteries have high CCAs - they are for starting engines. Any basic 60Ah battery recommended for a diesel would have no problem with a little MD1.
 

ghostlymoron

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I've always assumed the 60Ah maximum rating was something to do with the limited generation capacity of the Dynastart generator. (135watts)
The Workshop manual for the MD1 specifies 60Ah max
The recommended battery for the very slightly larger MD1B is 60 Ah max.

A 60Ah car battery would be a good choice and more than adequate I suggest!
Nobody seems to be able to explain why VP quote maximum capacities
 

scottie

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Max size batteries could prevent starter dynastarter burnout I believe was the reason quoted at the time

You may also recall that a dynastarter ran extremely hot just charging so that again could have been involved
 
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VicS

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I've always assumed the 60Ah maximum rating was something to do with the limited generation capacity of the Dynastart generator. (135watts)

Max size batteries could prevent starter dynastarter burnout I believe was the reason quoted at the time

You may also recall that a dynastarter ran extremely hot just charging so that again could have been involved

That could well be right although you will find a maximum capacity specified for later engines which had alternators not Dynastarters. 70Ah maximum for the 2001/2/3 series for example.

I've often wondered if it was to do with the high current that the battery could deliver to a stalled starter motor, a larger battery perhaps being able to deliver a current that would damage the motor, or the wiring.
 
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