How long should a properly running E30 be able to hold a charge without starting?

[IS300E30]

I have a 1987 325ic and its all original.

How long should a properly running e30 be able to hold a charge without starting?

[ELVA164]

I mean, I've gone almost a month with no issues. Not sure how much longer would work, but a month shouldn't be too rough. How long is it taking your car to drain the battery? Did you test for parasitic draw?

[Das Delfin]

I've gone two weeks and been okay. But if you only drive it once a week on the reg, it will kill your battery over time

[dnguyen1963]

Get a floating charger from HF if you don't drive your car often.

[e30onBBSs]

You can disconnect your negative terminal as well

[McGyver]

There are a lot of factors involved, but I would say that a car driven regularly before being parked with a good battery and without parasitic draw should be able to last a month.

That being said, I have a couple of car that I barely drive (just move them a a block or two every week or so) and those batteries barely last a month of sitting in the cold without being charged up. If you're going to leave your car parked for a while, I would disconnect the negative terminal to keep the OBC and radio from slowly draining your battery.

[nando]

From experience, if its more than 6 weeks get a trickle charger.

[agent]

Get a CTEK charger from Amazon if you don't drive your car often.

Fixed.

[M-technik-3]

Depends on few factors, temperature and overall condition of battery, plus charging system and any draw. I have gone over a month. I would leave my car in long term at Frankfurt and the other one at Ramstein. That way I'd have a car on landing.

[dnguyen1963]

Fixed.

$70 vs. $7? I have used HF charger for years without any issue.

http://www.harborfreight.com/automatic-battery-float-charger-42292.html

w/o 20% Coupon.

[agent]

$70 vs. $7?

That's half of what they cost with the Porsche emblem on them. ;)

[nando]

$70 vs. $7? I have used HF charger for years without any issue.

http://www.harborfreight.com/automatic-battery-float-charger-42292.html

w/o 20% Coupon.

$7 that could potentially burn down your house or ruin a $100 battery. Sorry, no way in hell would I trust that. HF is good for things you'll only use once, or really simple tools that can't fail. The electronic products they sell are complete garbage.

I have a Battery Tender Plus for my E30 - it's a bit cheaper than the one agent posted, but it's only 1.25 amps. enough for my use, and it will still charge a battery if it's not completely dead, it just takes a lot longer.

[Das Delfin]

Battery maintainers are meant to be left on the whole winter while you don't use your car. I wouldn't really feel safe using one of the $5 HF chargers. Battery Tender brand chargers are really good. Also Schumacher chargers are neat too, usually with more options than BT for a similar price

You can get a decent one for like $35

[TobyB]

Mine sits for months sometimes in the winter.

A lot depends on your battery- some have pretty high self- discharge rates.

t