Hot start dragging - battery?

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frlrubett
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Hot start dragging - battery?

Post by frlrubett »

So this Rocco has a reconditioned engine. 1988 Scala 1.8. Cold start is perfect but the hot cranks very slowly, turns over once before sticking. Repeated attempts and the engine does fire.

Mechanic has said the battery (came with car two years ago) could be underpowered. What battery specs do you recommend?

Is there alternative things I could look at before I start putting new batteries in?


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GT_II
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Re: Hot start dragging - battery?

Post by GT_II »

Easy starting with the engine cold and slow cranking when hot is not what I would expect from a weak battery. As for specs, the original battery was specified as 45Ah, 220A (I assume DIN, equivalent to about 360A SAE). Most modern batteries on the market exceed this comfortably.


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unknownmale
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Re: Hot start dragging - battery?

Post by unknownmale »

Also worth checking your connections, the earth from the battery to the body and power feed to the starter. see if they're loose, have any corrosion etc.


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essextom
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Re: Hot start dragging - battery?

Post by essextom »

as above, earths or dicky starter motor.


mark1gls
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Re: Hot start dragging - battery?

Post by mark1gls »

Take the earth connections off the battery and give them a good clean up with a wire brush, also follow the earth lead and clean up the other connections.
Another mod is to use a Mk3 Golf earth lead as that has a bit of extra cable which also connects to the engine block at one of the gearbox bolts, you may be able to add just an extra bit of earth cable from the gearbox mount to the engine block...?

Also worth cleaning up the connections on the starter motor.

A lot of places will test your battery to see if it’s any good, cheapo battery’s can last as little as 12 months.

https://www.eurocarparts.com/p/bosch-s4 ... -444770637

£50 with discount.... but get yours tested and connections cleaned before throwing money at the car.. :-D


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Nate
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Re: Hot start dragging - battery?

Post by Nate »

My old mk2 was like this. New main earth cable from battery to engine cured it. Check for this by putting a single jump lead from battery -ve to the block and see if it improves
Last edited by Nate on Thu Jan 09, 2020 9:35 pm, edited 1 time in total.


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james butler
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Re: Hot start dragging - battery?

Post by james butler »

like nate says change the cable first and go from there


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