BMW Battery Question 2001 E38

Put the biggest battery you can fit in there. H7, H8, H9 I’m sure they all fit in there. Lead acid.

Cool, thanks Jose.

Bmw used different sized batteries depending if vehicle had cellular phone etc

Good to know, thanks Manuel. {Edit} This damned thing still has the original cell phone in the center console cradle. It looks like what E.T. used to phone home.

i would use a Interstate MTP95R/H9 it will be your best choice for the vehicle.

Thanks, I am suggesting an H9 but I don't deal with an Interstate distributor.

Tony. Thank God I haven't seen any of these fine machines in a long time! Most of the ones I get calls on or get towed in get removed the same way and end up in the dump. Honestly that's where they belong, IMHO. On your comprehensive eval. pay attention to oil leaks, crankcase pressure (16.0 mBar) Timing chain issues…if it's got over 100K tell em to dump it. I believe your Battery question…

Luckily he knows already it's an oil leaking time bomb, but he'll probably ride it to the junkyard that way. As far as the crankcase test, this is a spec at hot idle? Do you just attach gauge to dipstick tube or should something else be done as well for this spec to be valuable? Thanks for the advise.

Tony. Glad he knows it's a black hole on wheels! :-) I use a magnehelic gauge, dipstick is a great point of entry if you don't have a dedicated fill adapter, regular vac. gauge won't show anything! I don't know if any of the common pressure adapters will go this low, are that sensitive?? Someone will know! Of course lets mot forget about the oil burning issues at prolonged idle….. Best, Dan…

I have a digital manometer, it will read in this range.

Dan, I got a fairly steady -12.5 mBar (tool zeroed and referenced to atmoshphere). Attached is a shaky cam video of me trying to hold the phone+meter and keep the hose out of the cooling fan. Does this indicate too much PCV volume or is this normal?

Morning Tony. I assume it was idling @ 675-800. Take a look at the Vent diaphragms for rupture, holes. F/T should be elevated or perhaps engine is just weak? Best, Dan @ G.E.A.R.

Originally you had stated 16mBar as a spec, and since I don't know squat about BMWs nor how their PCV systems perform at idle I took that to mean 16 mBar “pressure” as was the crux of the discussion, not 16 mBar “vacuum”. So these engines and their fairly complicated PVC systems still act fairly similarly to what I'm used to. I don't think that 3.5 mBar above spec is a nail in the coffin for…

Hi Tony depending on your coustermer driving habits it might be a good idea to use AGM battery which can handle key off draw better alot of them came originally with a valve regulated battery which is what a AGM battery is

Thank you, that might be a good idea; I think this does sit for extended periods ever since Covid.

No battery registration if no IBS, for sure. We have found BMW battery prices to be pretty reasonable.

Thanks, Paul. Local dealer is one week out on the battery and states 278 clams list. Doesn't know if it's AGM or conventional.