Cold starting with gel / undersized racing batteries

nbell · #1 03-11-06

I use a smaller than standard battery in my car as explained here. This has worked well all year but I notice it does not like the cold mornings...has not let me down yet but sounded quite sluggish trying to start this frosty morning. I wonder if it might fail if it gets much colder. I know a few people on here have these Optima / Odyssey / Red Top types of battery, would like to hear your cold starting experiences.

Albert Trout · #2 03-11-06

My Red-Top's been going great guns, no difference from the summer, and it's been Baltic here all week, but I don't think that's what you want to here Nick....

nbell · #3 03-11-06

Cheers Graham. On the contrary, I want to know if this mod was wise or not

Gauge indicated about 5 degrees here (11am) when I started the car. So yours turns over as normal in the same sort of frosty temps? Hmmm, maybe something else is unhappy then...

Did you sell your Saab gauges ok?

philb · #4 03-11-06

Was it just the sound that was sluggish, or the speed that it turned over? Reason I ask is that the starters make a lot more noise when they are on the way out, maybe the cold mornings have triggered that.

nbell · #5 03-11-06

Quote:

Originally Posted by philb

Was it just the sound that was sluggish, or the speed that it turned over?

!?! You kinda confused me on that one Phil

It sounds just like it might if the battery was v low. Which its not.
A slow couple of cranks before it starts. As in a wuuh (tiny pause)-wuuh (tiny pause)-BROOM rather than the normal instant br-BROOM.

Apologies for sound effects

unkleG'sif · #6 03-11-06

could be that the alternator, voltage regulator or brushes are gettin tired.... if its not charging the battery properly, then there will be less power to crank the engine (esp when cold and the oil is like treacle

)

get a voltmeter across the battery and see if it has 12v.. also from alt to earthing point?

interesting this, as a slim battery is one of my future mods

G

nbell · #7 03-11-06

Quote:

Originally Posted by drg23

could be that the alternator, voltage regulator or brushes are gettin tired.... if its not charging the battery properly, then there will be less power to crank the engine (esp when cold and the oil is like treacle

)

get a voltmeter across the battery and see if it has 12v.. also from alt to earthing point?

interesting this, as a slim battery is one of my future mods

G

I think its charging the battery ok, the voltmeter reads about 13v as always. When I take these measurements, the car should be off and cold? I can do that tomorrow morning. Cheers G.

Matthew · #8 03-11-06

Quote:

Originally Posted by philb

starters make a lot more noise when they are on the way out

Interesting. Could you describe the sound?

My new 900 sometimes makes a strange sound when I'm starting it and I'd like to know what the problem is.

nbell · #9 03-11-06

Quote:

Originally Posted by Matthew

My new 900 sometimes makes a strange sound when I'm starting it

Grrrrr woof woof! perhaps Matthew?

Albert Trout · #10 03-11-06

Quote:

Originally Posted by nbell

Cheers Graham. On the contrary, I want to know if this mod was wise or not

Gauge indicated about 5 degrees here (11am) when I started the car. So yours turns over as normal in the same sort of frosty temps? Hmmm, maybe something else is unhappy then...

Did you sell your Saab gauges ok?

Aye. Knew I'd forgotten to check on something when I took them out. Sorry about that

I've had to de-ice the car last 3 mornings. Also I managed to leave the ignition on all night (don't ask) about a month ago and had to recharge it, so I'd reckon yours should be in a better state than mine.

unkleG'sif · #11 03-11-06

Quote:

Originally Posted by nbell

I think its charging the battery ok, the voltmeter reads about 13v as always. When I take these measurements, the car should be off and cold? I can do that tomorrow morning. Cheers G.

from alt to earth, i think the ign should be on, but not running... doesnt matter if cold or not i dont think,

maybe you should compare the cranking specs of your battery, to the requirements of a stock one, and those of Alberts, as he seems to be not having the same problems

G

nbell · #12 03-11-06

Cheers G. I will check that. My battery did provide the same crank amps as the standard one, I checked that before purchase. The reserve is rather lower though

;

PC 680MJ Specs:

680 cranking amps for 5 seconds
595 cranking amps for 10 seconds
525 cranking amps for 20 seconds
Short circuit current over 1800A
17 amp hours
25 minute reserve capacity with 25amp load
Female brass terminal w/M6 SS bolt
With metal jacket
Length 7.27"
Width 3.12"
Height 7.42"
Weight 15.4 lb

Albert Trout · #13 03-11-06

Cranking amps and almost everything else is pretty much identical to mine. My Varley actually has 16 amp hours to your 17, so I reckon you can rule the battery out, unless it was defective when you bought it.

nbell · #14 03-11-06

Quote:

Originally Posted by Albert Trout

Cranking amps and almost everything else is pretty much identical to mine. My Varley actually has 16 amp hours to your 17, so I reckon you can rule the battery out, unless it was defective when you bought it.

Awwwww C O C K

Its been working great all year. Something else then maybe - will get the voltmeter out tomorrow.

Matthew · #15 03-11-06

Surely a bad battery is still favourite for bad starting on cold mornings? Classic symptom?

Maybe this is just a symptom of a different problem. If the battery's not being charged properly, then it'll suffer in cold temperatures. Time to test the charging system!
http://www.saabcentral.com/forums/sh...ad.php?t=61973
http://www.saabcentral.com/forums/sh...ad.php?t=62108

Going to move this to the C900 Workshop, as the problem will get better explosure there.

philb · #16 03-11-06

Sorry about the confusion Nick, it does sound like your engine is turning over slower than normal. Could still be the starters fault though, getting older and drawing too many amps. Matthew - I've sold the lpt, which sounded like that, but it basically sounded like a tractor when cranking, smooth once it fired.

nbell · #17 03-11-06

Quote:

Originally Posted by Matthew

the problem will get better explosure there.

Freudian slip Matthew? Memories of a battery that went BANG! perhaps

jetman · #18 03-11-06

I have had several bad cold morning start problems. Batteries were fine. Positive cable to starter was not!

Si · #19 03-11-06

Do you park your car facing the direction of the wind?

The last place i lived at had a very windy alley, if my mate parked his car facing the direction of the wind for some reason every morning the battery would be dead or nearly completely discharged, was fine the rest of the year, only happened when the temp dropped below about 10 degree's.

If you want to do a cheap test, pop the bonnet and tuck a blanket in over the grill/front bumper, see if it's any different/starts better the next day.