4LW starter battery size

[XLD]

My 12V 135 AH 850A battery has died. 
just wondered if a smaller one would do the job. 
be easier to obtain.

[BEngo]

Which starter is fitted?  The lock torque current of a 5in diameter starter (CAV BS5) is about 500 A, the 6in starter  currents are more.  So long as the battery CCA is greater than the starter lock torque current you should be OK, though a small capacity high CCA battery is not likely to have a long life.

 

N

 

 

 

[David Mack]

Obtaining another like your original should not be difficult from online suppliers such as Tayna.

I can't say whether a smaller battery would do.

[DShK]

~100ah ~850 CCA from halfords fairly easily. 30ah won't make a difference, it's just the CCA.

[MtB]

6 hours ago, XLD said:

My 12V 135 AH 850A battery has died. 

 

Not wishing to be doing the egg sucking thing, but are you confident your alternator is working correctly? 

 

Back in the day I bought a new batt for my car whilst casually dismissing the idea the alternator wasn't doing its stuff as the red light went out correctly. Guess what happened a few days later! 

 

 

 

[Tony Brooks]

1 minute ago, MtB said:

 

Not wishing to be doing the egg sucking thing, but are you confident your alternator is working correctly? 

 

Back in the day I bought a new batt for my car whilst casually dismissing the idea the alternator wasn't doing its stuff as the red light went out correctly. Guess what happened a few days later! 

 

 

 

 

9 diode alternators will put the warning lamp out even with blown main diodes, but the charging voltage and current will be low. Actually, the warning lamp could also glow dimly that you would not see in daylight.