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General Information => General => Topic started by: 8v-of-fury on December 13, 2010, 10:39:08 pm

Title: Running dual batteries
Post by: 8v-of-fury on December 13, 2010, 10:39:08 pm
1981 1.6D N/A

manual glow-plugs, gave it about 15 seconds of them. and went to start engine gave two chugs (so two compression strokes) and the starter let loose from the engine and began to spin by itself.. Several times more it did this until the engine caught. I think if it would have cranked one more time on the first go it would have done sufficiently. Why is it doing this?

After getting started it ran great! ;) Long Live The 1.6D lol
Title: Re: -17C cold start
Post by: vanbcguy on December 14, 2010, 12:15:57 pm
Not 100% sure about VW starters but most others I've worked on have an overrun clutch, this is to prevent the starter from getting spun up to a gazillion RPM once the engine catches.  If it goes bad it often has the symptoms you are describing.  Other possibility is the starter has gotten sticky and the pinion isn't engaging properly with the ring gear on the flywheel - if that's the case it'll often make some unpleasant crunchy noises as the teeth slip off.
Title: Re: -17C cold start
Post by: 8v-of-fury on December 14, 2010, 12:37:49 pm
Thanks dude. Yeah I think its the latter of the two things you described, as it is doing the described crunch as the starter slips off the fly wheel.. Good thing I got a few laying around
Title: Re: -17C cold start
Post by: erice1984 on December 14, 2010, 06:52:55 pm
Those are the noises mine makes as well..  Although it only does this on the first start of the day, other than that it does just fine until the sun goes down.
Title: Re: -17C cold start
Post by: theman53 on December 15, 2010, 07:28:57 am
I replaced my batt terminal and wire with the 1/0 I had in the flat red bunny. Yesterday no block heater, one cycle of glow plugs, and it fired and ran on the second revolution. It was 1F :D
I had been having hard starts when lots warmer. I noticed my GP wiring that I had made was a little "loose". #4 was still attached, but 1,2,and 3 piggy back off of 4 and it was broken right at for. After getting them all back up and going that is when I started it at 1F ;)
Title: Re: -17C cold start
Post by: 8v-of-fury on January 17, 2011, 07:33:24 pm
WELL last night, I tried to call on the old beast to start.. and it just wouldn't do it :(

However it was -25C before the windchill :o and it had been sitting 1 week to the day since I parked it where it was to bring a 91 in to the driveway to strip in this ungodly weather..

I feel that upgraded battery cables (Lucas I will go as big as I can possibly get ;)) Now I had an idea. Say I want to run two batteries in series (++ and -- Vince where are you? lol) the voltage will remain at 12v, but will the batteries amperage be each of the batteries together? For some reason my brain failing, and bringing up reasons as to why I'm wrong lol. I figure with like 12-1250CCA you could literally spin the engine up to temperature if you absolutely had to.. lmao
Title: Re: Running dual batteries
Post by: rabbitman on January 17, 2011, 08:02:34 pm
Yeah you could do that, as long as it's 12v it'll be fine. The starter will only draw what it can use so it's best to have a bit of overkill rather than underkill. If you get an unfused short with two batteries it'll be more exciting too.

On the starter, my money says the overrun clutch is going. I had that same issue a while back so I bought a new starter gear, but it couldn't hold the power of the starter. Rather than crank and then slip the new piece would slip and then grab.

I put a used drivegear from a gasser starter in and it's been fine for a year or two now.

New parts aren't near the quality of the old stuff............
Title: Re: Running dual batteries
Post by: maxfax on January 17, 2011, 08:05:40 pm
I remember your post about that Rabbitman.. I think we were both having the same trouble at the same time.. Worked ok when warm, but kicked out when cold..  I warrantied a pile of reman VW and Benz starters till I gave up and installed a genuine Bosch drive from a used starter...
Title: Re: Running dual batteries
Post by: rabbitman on January 17, 2011, 08:11:14 pm
I remember your post about that Rabbitman.. I think we were both having the same trouble at the same time.. Worked ok when warm, but kicked out when cold..  I warrantied a pile of reman VW and Benz starters till I gave up and installed a genuine Bosch drive from a used starter...

Yup that was the deal, kinda sad that once the supply of old drives goes extinct us dieselers will be up a creek.
Title: Re: Running dual batteries
Post by: Vincent Waldon on January 17, 2011, 08:12:50 pm
+ to + and - to - is the ticket..  Theoretically you will then have the amperage of both batteries available..

True dat.  That's wiring them in parallel.    Series would give you 24V.. which would certainly spin your engine fast.... a couple of times.  ;-)

The only subtlety is that over time the batteries will age and their charging/discharging characteristics will become different... and they will start to fight each other a bit, since they are chained directly together.

There's a super-duper belt-and-suspenders approach using a battery isolator for charging and a starter solenoid for starting, but for the purposes of day to day life chain 'em together with the heaviest cable you have and drive more, worry less.   ;)

Early MGs had a 6V electrical system that used two 6V batteries chained together... worked fine.  They mounted them under the passenger seat exactly on opposite sides of the transmission hump for perfect weight balance... clever Brits.  ;-)

OK, back on track.... yeah, sounds like your starter's overrun clutch is releasing prematurely.  Pretty common failure mode as they age.
Title: Re: Running dual batteries
Post by: maxfax on January 17, 2011, 08:14:40 pm
I still have to wonder of it could have been an issue with the grease they used in the drives..  Say something like it's too stiff when cold..  I had to replace the starter on the current bunny early in the spring..  I had troubles with it kicking out till the weather got warmer..  I just dealt with it since I could usually get it started..  Once summer hit it was fine, and now that it's cold again it still seems to be working fine...


Quote
The only subtlety is that over time the batteries will age and their charging/discharging characteristics will become different... and they will start to fight each other a bit, since they are chained directly together.
   

And to add to this, start with 2 batteries at the same point in their life, ideally new.. 
Title: Re: Running dual batteries
Post by: 8v-of-fury on January 17, 2011, 09:00:12 pm
Yeah I would only run two batteries because I have a few extra laying around, and that way I mean it could crank and crank and crank and it would take a while to run the batteries down. Plus having that extra amperage around to use instead of the alternator trying to make up for surges..

Both batteries are used, so when they start to get worn down or get older.. I will get two cheaper priced 500cca batteries or something similar in lower price (to be able to run two relatively inexpensively).

Rather than mess around with the starter, I think I'll just swap in a known good original vw D starter.. and keep this one around, in case i run out and need to rebuild one. lol

Thank-you guys very very much :)
Title: Re: Running dual batteries
Post by: truckinwagen on January 17, 2011, 09:28:05 pm
I am running two batteries right now, and have on many cars.

never had too much trouble with them dying  faster due to them being wired together, they are asked to be run flat less often so they tend to last longer.

even on really cold days when my GP's are not working properly I can crank long enough to fire up without killing the batteries. helps alot when I have to park the car all day without a plug for the block heater.

as for the starter, mine is slipping loose of the ring gear when cold too(not a VW starter, but hey) and I will be replacing it as soon as I can, so I can look at what is wrong with it then.

-Owen
Title: Re: Running dual batteries
Post by: 8v-of-fury on January 18, 2011, 02:48:19 pm
Duals it is then, this might make it possible for me to dig my Diesel out of storage and drive it for the rest of winter! However I need to do work on it :( lol

How long do you figure it will take to replace all the struts/shocks in my driveway?
Title: Re: Running dual batteries
Post by: GEE-BEE on January 18, 2011, 09:23:33 pm
I have a dual VR40 Odyssey Horizontial mount being made for the caddy..

it was almost 80 here today at the beach thou...

leaving for Osaka japan tomorrow , then off to Boracay island

GB
Title: Re: Running dual batteries
Post by: truckinwagen on January 18, 2011, 09:26:05 pm
shocks and struts are not too bad, if you have an impact then it is a cinch.

I did my last set in about 2.5 hours

-Owen
Title: Re: Running dual batteries
Post by: RabbitJockey on January 19, 2011, 04:47:40 am
i guess my clutch hasn't been releasing right away then, after i start my car theres a little burrrrrrr for a second that starts, been using it like this for a while tho, probably a year, i figured if it matters it will break or make louder noises haha
Title: Re: Running dual batteries
Post by: 8v-of-fury on January 19, 2011, 07:52:06 am
I just picked up a 77pc. air tool set for a steal from Canadian Tire.. Sadly my compressor now needs upgrading.. By means of a bigger compressor lol :( so its hand tools for me.

I just can't stand the horrible mileage I get in the 1.7 gasser! CIS FI can politely take off ;) EH

GB that sounds a good idea, Enjoy your adventure!

I just found out the battery I pulled from the TDI is a 900cca!! That mated to my unknown battery (was one of two from an F350.. Gotta be big.. Could crank that thing forever!) Will be unstoppable! Could listen to my sterio all night and still startup in the morning lol.

Thanks a bunch guys!

Ps. Trev as long as it engages before you start raising rpms.. I'd think it would be fine.. ??
Title: Re: Running dual batteries
Post by: R.O.R-2.0 on January 19, 2011, 10:33:48 am
Duals it is then, this might make it possible for me to dig my Diesel out of storage and drive it for the rest of winter! However I need to do work on it :( lol

How long do you figure it will take to replace all the struts/shocks in my driveway?

rear struts take about a half hour, to do both sides..

fronts take a spring compressor to even get them off the car..

dont loosen that big nut on the strut bearing without having the spring compressor on. i just take and put the compressor on while there is still load on the suspension, then i take the load off the suspension and the compressor is tight, and assembly ready to come out..

pop the ball joint, and tie rod end, along with the brake caliper and that big strut shaft nut, and the whole thing will come down out of the car..
Title: Re: Running dual batteries
Post by: 8v-of-fury on January 19, 2011, 10:38:14 am
k3vo! I've done shocks on my 84, and I've taken the strut assemblies out before.. Just I think getting the strut inserts out will be the biggest issue.. I lack a vice :(

I also have a nice new set of springs to go on too :D 1" drop sports.
Title: Re: Running dual batteries
Post by: R.O.R-2.0 on January 19, 2011, 10:42:02 am
take a punch and LOOSEN (not remove) the strut retaining cap while its still on the car. should be do-able.. thats how i was going to do it atleast.

i wish i had 2 sets of jeep rear coils.. i would lift my rabbit..
Title: Re: Running dual batteries
Post by: rabbitman on January 19, 2011, 07:15:00 pm
I've been thinking of running two batteries for a while now, at 0F it better start within 3 seconds of starting to crank or it'll die.
Title: Re: Running dual batteries
Post by: 8v-of-fury on January 19, 2011, 07:33:13 pm
Yeah tell me about it! Canadian tire has some good 950cca on for like 119$.. If you could find similar near you.. Those together would be incredible overkill.. But it would start everytime ;)
Title: Re: Running dual batteries
Post by: theman53 on January 20, 2011, 05:25:18 am
I seem to think that there is no such thing as underkill :D I have right 1,000CA batteries in just about everything I drive and where I live it wasn't quite enough on colder days with the old diesels. This new TD starts as good as a gasser though. It has the neverstart maxx with 850 or 900CCA though :D