Diesel engine starter current draw ?

Boo2

Well-Known Member
Joined
13 Jan 2010
Messages
8,603
Visit site
Hi,

I'm selecting parts to fit out my new engine installation and I need to spec things like cable and battery isolator switches etc and I wondered what current I should specify for ? Engine is a Nanni N.38 which is a 1500cc N/A diesel.

Thanks,

Boo2
 
Look for switches capable of 500 amps. The more robust the better life expectancy. Cables depending on run length should also be suitable for 500 amps. good luck olewill
 
Hi,

I'm selecting parts to fit out my new engine installation and I need to spec things like cable and battery isolator switches etc and I wondered what current I should specify for ? Engine is a Nanni N.38 which is a 1500cc N/A diesel.

Thanks,

Boo2


Typical cranking amps for a diesel engine that size would be between 200 & 300a depending on oil viscosity and engine temperature, condition of starter, compression rating etc, so look at the upper end of that, typical shortish run would use 50mm2 cabling and most decent battery switches will cope with more than that intermitantly, their specs are always shown in the info. Make sure all terminals are well made and protected against corrosion. Using 50mm2 on say a 10 foot round trip on the 50mm2 cable drawing 300a would give you 11.25v at the starter assuming 12v at the battery, obviously a well charged battery is over 12v.
 
Last edited:
You may find that your engine manual specifies the battery CCA (cold cranking amps) needed. The manual for the Beta 38 (4 cylinder, 1500cc - probably the same base engine) suggests a battery of 450-540 CCA.

How closely that nominal battery output capability figure is to the actual amps delivered in practice, I wouldn't know.
 
Top