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Slow Cranking Speed
Mentat - January 18th, 2007 at 12:20 PM

Car: 1969 VW Baja Bug
Problem: Car will only crank 3'ish times before stopping.
Things I've Tried:
1/Replaced Starter Motor
2/Replaced Battery
3/Cleaned and Replaced Earth strap, and added extra Earths
4/Wired in starter relay

What I would Like: Ideas.

I cant help thinking that I'm overlooking something really simple, with the starter out of the car, it spins quickly and freely, but once in the car, it will only turn the engine over 3 times (slow-medium) speed before it stops, Its a 460CCA battery, similar to the one that cranks my V8 at good speeds. Please help.

Thanks
- Adam


vw54 - January 18th, 2007 at 12:23 PM

have u lubricated the bushing in the gearbox

is it the right starter and flywheel combo

ie hope its not a 6v starter matched to a 12v flywheel

or is it a 12V flywheel trying to fit into a 6v gearbox bell housing and getting bound up


Mentat - January 18th, 2007 at 12:39 PM

I removed the old starter, called the local shop. and got a new starter with the same numbers on it, greased the bushing and installed it ok. For the 3-4 times it cranks, theres no weird noises.

It cranks just like its got a flat battery, but I've tried the battery in other cars, and it goes fine.


Bizarre - January 18th, 2007 at 12:45 PM

Has it ever worked??

is this a new problem or a new car??


Mentat - January 18th, 2007 at 12:52 PM

new car (new to me, at least)

I bought it, and it started fine, and I drove it home, once home it only starts sporadically, initially, I thought it was just a bung generator, so replaced that, now when it starts, the battery charges (which is good). The accessories wiring in it was a big mess, so that has all been replaced,

but even with a copious amount of clippy leads (to eliminate any internal wiring issues) I still cant get it to crank quickly, or start reliably.


68AutoBug - January 18th, 2007 at 02:32 PM

I presume You have a relay for the starter motor..
located near the battery or starter motor...
Earth strap from the nose of gearbox to chassis has been cleaned at both ends..
so its like a new connection...
under the earth strap is shiney and polished...
New zinc plated bolt....
New zinc plated or stainless steel battery strap earth bolt and nut..
under the earth strap has been cleaned/polished..
all connections like New...

the bush the starter motor sits in, is it badly worn??
it has to be in good condition so the starter motor pinion will mesh with the ring gear correctly...

really, strange it starts OK in another car...

Starter key switch maybe the problem...
most are still the originals and the contacts are burnt and dirty... not allowing the full current thru...
try starting it with a switch and relay or just use the relay with a piece of wire to start the engine...

either its mechanical - electrical power - or electrical earth -

Lee

http://community.webshots.com/user/vw68autobug 


MickH - January 18th, 2007 at 02:53 PM

Bridge the starter with a large screwdriver,making sure it is OUT OF GEAR FIRST. If it turns over normally then you have an electrical problem,most likely an switching fault. If it doesn't turn over normally the power supply is faulty or the starter has issues,either a worn bush or faulty starter.Like Lee said....check the Earth strap and add another tempory one if you must.Does the motor turn easily by hand???


Mentat - January 18th, 2007 at 03:06 PM

Starter is on relay next to battery.
Earth wires have been replaced, earth points have been cleaned, new bolts.
Shorting the start makes it crank, but only the same as cranking it with the key.
Shorting the relay causes it to crank, but once again, the same as cranking it with the key.
the bushing the starter sits in seems in OK condition but I'll look at replacing it tommorow, its about the only thing I havent changed.

Motor turns over with a socket on the generator without any grinding, scraping, or excessive effort.

Would it be worth removing the spark plugs and seeing if that makes a difference to cranking speed? (stuck valve maybe making compression overcome cranking power?)


68AutoBug - January 18th, 2007 at 03:17 PM

Boy, thats a hard one...
If it doesn't crank properly when shorted out with a screwdriver...
its not the solenoid then....
must be that bush...
it keeps the pinion in the correct position..

If the bush is greased well and the pinion shaft too
so the pinion can slide & engage the ring gear easily...

the only other explanation is the ring gear is worn too much... and the pinion is binding... locking up...

You can file the ring gear or grind the edge off if its not too bad... but it doesn't sound too good...

if the bush in the housing is worn, and they wear egg shaped... because of the force on it by the pinion shaft..
a lot of force.... all the force of the starter motor...

Best of luck..

Lee

http://community.webshots.com/user/vw68autobug 


Matt Ryan - January 18th, 2007 at 03:35 PM

Going for the "out there" ones here, maybe timing out of whack? check static timing. Or, could be needle & seat stuck open in carby & combustion chambers filling up with fuel.


vw54 - January 18th, 2007 at 04:33 PM

Quote:

It cranks just like its got a flat battery, but I've tried the battery in other cars, and it goes fine.




What happens when you use another car using jumper leads

sounds like the NEW battery is FALT as well and needs a good charge

try using another battery n jummper leads while the jummper car is running
as per above is the oil level normal maybe hydraulicing


MickH - January 18th, 2007 at 05:24 PM

Sounds like the starter...even if it was replaced,it still sounds like the starter.I'm assuming the main power wire from the battery runs directly to the starter and the relay is only switching the solenoid?? I mean no offence but it all sounds weird.You've tried the fixes and they don't work.


68AutoBug - January 18th, 2007 at 05:49 PM

As Mick said, it seems You have exhausted all the things to do.... normally...

but I think You said the engine has started and has run...

but as Matt said, and this did happen to me, mainly as i have an electric fuel pump and it was left On...
some of the cylinders filled up with fuel...
which stopped the engine from turning over....
check the oil level...
as the fuel will end up in the oil...

and try with the spark plugs removed...

that will answer some questions...

Lee


76camper - January 19th, 2007 at 07:31 PM

check the earth strap from your battery to the chassis and also the positive wire running to the starter.

You could try using jumper leads from another battery directly to the terminals of the starter....


Baja Wes - January 19th, 2007 at 10:09 PM

I think it sounds like the new battery is faulty.


$2.63 homebrand baja - January 20th, 2007 at 10:39 AM

I went thru something similar not that long ago, bought new battery n swapped it twice, even upgraded to a bigger one in desperation, replaced the battery leads, had the starter n alternater tested, changed the ignition switch, ripped half my hair out in frustration and started bashing the car body with a rubber hammer to alleviate the pain..........end solution: the little brass bush in the gearbox had worn slightly on one side, creating a very slight oval hole, this prevented the starter from engaing properly and actually began heating things up, I replaced it but the starter chewed through it... bought a new one and had to use metal glue to hold it in place (once the bush had worn through it started to enlarge the hole in the bell housing..I only had a couple of mm till it completely stuffed things up, resulting in a possible engine removal and gearbox repair... as the auto electrician said, the starter was going strong :o)... I hate it when these things happen........to me...........all--the--time! :no:

edit: btw I have to admit it was a great learning experience, I discovered how volts and amps worked, how to use a hydrometer, how wiring deteriorates over time and that the swing axle shock absorber bolts make a great tool for removing that pesky bush when you have no other tool.. screw it in and it comes right out.. :lol: 'bloody backyard mechanics' :thumb



[ Edited on 20-1-07 by $2.63 homebrand baja ]


ExQuokka - January 21st, 2007 at 08:10 AM

Back up and re-read 68AutoBug's reply - it sounds to me more like an earthing problem, especially as it's a Baja. Many buggy owners would provide an extra Earth strap from the engine to the chassis or battery. You can put a meter on the terminal to check how low the voltage drops to verify this. The starter should be receiving close to 12V under load in this weather.


$2.63 homebrand baja - January 21st, 2007 at 09:56 AM

ExQ, r u directing the 'backup' statement at me? I assure you I meant no offence with my story, only offering my sympathy. I did read autobugs posts, as I said I had replaced the battery terminals, leads, sanded back/polished/cleaned the earth strap bolts, earthing point to body, terminals on the starter, the 'seconadary earth strap' on my baja was fairly new but I cleaned it all up and went around and replaced all terminal plugs in the circuit 'just in case' there was a dodgey connection somewhere. I was also worried that the battery wires and terminals along with the starter was heating up, figured this was due to corroded/damaged wires causing too much resistance. I Had the meter on and could see the correct voltage was passing through along with sufficient amps, but chose to overhaul the dodgey wiring anyway (had the original straps, they werent brilliant). I measured the volts and amps at night, then again in the morning to make sure there were no mystery leakages. Once I was onto my second battery (both of which did start another car fine) I tested the battery with a hydrometer, was coming up fine. My sparkplugs had recently been replaced and the timing was fine. I did check it was turning over ok, listened for any grinding coming from the flywheel, nothing was seized or rubbing, motor was turning freely.. I was just shaing my frustrating find after exploring every option and spending a load of money I didn't need to. Sorry to have appeared like a forum mechanic knowall, just sharing what i had found. I shall shut up from now on. :rolleyes:

[ Edited on 21-1-07 by $2.63 homebrand baja ]


68AutoBug - January 21st, 2007 at 03:29 PM

Hi $2.63 Homebrand Baja,

Your comments were OK in MY book....
it sounded fine....
as that was one of my thoughts too...
the small bush does have a LOT of pressure on it from the starter motor... and needs to be kept greased....

Your post may have helped people who have read it....
so please keep posting Your thoughts...

Good to hear from You, I thought You had disappeared from the scene...

cheers

Lee Noonan Scone


68AutoBug - January 21st, 2007 at 03:34 PM

One little thing I do do to VWs I've owned and to VWs I've rewired etc...

the bolt that holds the earth strap to the chassis, I use a new much longer zinc plated bolt and I put the earth strap from the gearbox to the same bolt - underneath..
so, its actually the best earth You can have...
as both are bolted with the same bolt...
I can't remember whether a longer earth strap is used....
as You can buy those very easily...

cheers

Lee


greedy53 - January 21st, 2007 at 07:18 PM

key stuffed


Mentat - February 14th, 2007 at 05:30 PM

After much wrestling, swearing, contorting, and threatening to build a pit/buy a hoist, I have finally got the starter bushing out, I tried the 'pack it with grease and pop it out' method, it failed, so I ended up threading a bolt through it and turning it out, now I have another dilemma,

I like my new pieces to somewhat resemble my old pieces when I'm installing them, lets me know I'm on the right track :). below is a dodgy picture of my dillema.

http://www.panelvan.net/bug/startbush.JPG

The one on the left being the old one, and the one on the right being the new one... (neither being inscribed with 'one ring to rule them all')

Is there only 1 type of bushing for 12V bugs? or do I have the wrong one?

Thanks
- Adam


$2.63 homebrand baja - February 14th, 2007 at 06:37 PM

you have the wrong one, I had the exact same problem as per my posts above, one stupid little tiny bit of brass stopping my whole car, was given the exact same bush! :cussing take the original back to the place you got the new one from, you'll need the same as the first without the funny hole! :lol: Is I found with my heinz special baja, NOTHING fits in the 'one ring/weird bit/what the hell was the last owner thinking' category.........but It's a wonderful learning curve :td: :lol:


Mentat - February 14th, 2007 at 07:16 PM

Does this give any indication of what engine/gearbox I actually have? I cant seem to find any identifying numbers on anything :).

Also, might the starter I have been given be the wrong one, as I was given the new bush with it?


vw54 - February 14th, 2007 at 07:40 PM

OK lets start at the begining again

What gearbox
What flywheel
What starter give me cold hard facts


$2.63 homebrand baja - February 14th, 2007 at 09:02 PM

when they swapped the starter did they check it was the same length (shaftwise)? if so it may be fine, just guaging the diameter of the actual hole in the gearbox caused problems for me, I found there wre two variations in that bush; same length but two different thickness's so consequently when you put the thinner one in, it will just slide about and the flywheel will just chew it up (and your starter shaft will damage the hole in the gearbox), if you look the internal hole is matching, it's just the external thickness which is the problem. That shaft has to have a pretty snug fit to engage properly on the flywheel.


Mentat - February 23rd, 2007 at 05:07 PM

Quote:
Originally posted by vw54
OK lets start at the begining again

What gearbox
What flywheel
What starter give me cold hard facts


All of the above is mostly unkown, unfortunatley, I seem to have bought someone elses problems.

I've taken the old bush the the VW shop, and the replacement says 6V case to 12V starter, how can I check if the flywheel correct?

Is there any special trick to reinstalling the bush, or do I just grease it up and drift it in?

Thanks
- Adam


Judsons4eva - February 23rd, 2007 at 11:34 PM

I had the same problem and tried all the above fixes then I purchased a brand new Brazillian Bosch starter. It is a lot smaller than original VW starter but uses modern materials and design. It spins the thing over like its a Honda.

Part no SR15N

I think Mick Motors has them. I got mine in Fremantle from Kurt.

Ken

[ Edited on 23-2-2007 by Judsons4eva ]


Mentat - February 26th, 2007 at 09:20 AM

if this fails, then i will try a newer model starter,

should the new bush need to be forced/pressed in, I've just popped it in, and it slid in with very little resistance (could push it in comfortably with my finger). Just gotta charge the battery again and see if my problems are solvered


Mentat - February 26th, 2007 at 10:51 AM

Well, it was a long a panful process, but replacing the bush has solvered all my starting problems, I now have an orange baja that cranks like lightning.

I'm kind of glad I've had to go through all this, by changing almost everything, and redoing all the wires, I've hopefully staved off any future electrical gremlins, now onto the next problems :).... but thats a whole other post.

Thanks for all your help on this one, I wouldnt have even thought that such a small piece of brass could cause such a problem.