Club 80-90 Forums

What is an acceptable amount of charging loss overnight for my battery in my Petrol T-25. I was told the original engine was replaced with a porsche 2.0 liter engine. I check it after I park it for the night and check it again in the Am. It only drops a few points and is still above 12V but I still have a hard time getting my van started in the AM. I have to jump it off, and when I do so it cranks right up. If I wait until later in the morning to start it when its warmer it has less of a problem starting. After it starts the first time it starts great all day no matter how many times I start and stop it. The battery I have has I think 510 cranking amps. I would think this would be enough. Is this just a regular cold starting problem or is my battery going bad. Do I need a larger battery for my engine? I know this is a ton of questions but I appreciate any help.

What is the terminal voltage on your battery? It should be about 12.6 to 12.8 V fully charged.
How much does it drop overnight?
You say it is still above 12V, but that would be all but flat.
Is the battery charging? What is the voltage with the engine running.
Cranking Amps should be fine, but only if the battery is charged.

T

it is 12.7 to 12.8 V fully charged and may drop to 12.2 or 12.4 by the AM. It runs around 13.9 to 14.1 when running so yes it is charging. Thanks for the response.

Disconnect battery overnight and do the same test. If it's the battery you will have near on the same drain but if it doesn't drop and starts fine when reconnected then you could have a power drain somewhere else on the van.