6 replies to this topic

[Arthy]

Hi guys!

 

Since my engine rebuild to fast road spec, cold starting has been difficult. The engine struggles to turn over which it seems like a flat battery. The battery in my car hasn't been used for 6 months but I have charged it a bit before using it again.

 

I have to jump start it from cold, but even then it struggles to turn it over but it's just enough! (The jump battery could do with a charge though!)

 

I'm starting to think it's a weak starter motor due to the new/high compression engine? Would a standard pre-engaged starter be enough to start it? 

 

So I'm either thinking of getting a new battery or high torque starter motor? OR it could be a bad engine earth or ignition timing? The car starts easily when warm though! 

 

Any help is appreciated! 

 

Arthur

[nicklouse]

charging it a bit! what does that mean? get it on charge and dont try starting it till it is fully changed. then you might have an idea what is happening.

[Swift_General]

What voltage is showing across the starter motor after a fully charged battery when cranking?

[Arthy]

Sorry!! Forgot to mention the voltmeter is showing a solid 12v when ignition is on! I'll check what the voltage is across the starter tomorrow when turning over!

 

I just thought even with 2 batteries (albiet not fully charged) it would turn over easily? I'll give them a good charge tomorrow too! 

[Swift_General]

I would expect a fully charged rested battery to be showing no less than 12.6v (no load). Check this, then voltage accros starter motor when cranking, and voltage accross battery when cranking (to determine any unusually high voltage drop).

[nicklouse]

Sorry!! Forgot to mention the voltmeter is showing a solid 12v when ignition is on! I'll check what the voltage is across the starter tomorrow when turning over!

 

I just thought even with 2 batteries (albiet not fully charged) it would turn over easily? I'll give them a good charge tomorrow too! 

so almost flat. understand the condition of a battery. also have it drop tested (for how long it holds a charge).

 voltchart1.gif   6.43K   2 downloads

[timmy850]

Best way to check the battery it to take it to a battery shop and get them to do the load test on it.