Two questions regarding battery earth & alternator..?

[jaylee]

Two earth straps come off the negative side of the starter battery.. (Both black & yellow wires.) One goes to just inside the drivers wing..
The other earth strap follows a loom down to where??

Using a meter off the alternator, what is the best place to probe for testing the units output..?

Cheers!

[stilldesperate]

Hi Jaylee,

There's a large stud connector on the alternator, that has a 10mm? nut on a stud. You should read battery voltage on this with the engine not running, and this should increase when the engine runs.

Fraid i cant help with the second earth lead, but I fixed a charging fault on another Bongo earlier this year, the fault was that the alternator wasnt earthing well enough to the chassis.

A temp fix (still in place ) was to run a large diameter cable from the alternator body to under a bolt by the gear stick. Lots of wierd faults were then cured (chirping low coolant alarm, high temp guage, dim interior lights)

Hope this helps.

SD

[jaylee]

Hi Jaylee,

There's a large stud connector on the alternator, that has a 10mm? nut on a stud. You should read battery voltage on this with the engine not running, and this should increase when the engine runs.

Fraid i cant help with the second earth lead, but I fixed a charging fault on another Bongo earlier this year, the fault was that the alternator wasnt earthing well enough to the chassis.

A temp fix (still in place ) was to run a large diameter cable from the alternator body to under a bolt by the gear stick. Lots of wierd faults were then cured (chirping low coolant alarm, high temp guage, dim interior lights)

Hope this helps.

SD

Cheers SD,
Does it have a rubber cover over it at the back & bottom face of the alternator?

I don't "appear to have a charging fault" what i did have the other day was what appeared to have a flat battery..? (About a year & a half old?) I had about 5 or 6 volts showing on my in built volt gauge, dropping when trying to crank. & a healthy 12.5v when testing the battery with a separate meter, engine off.... (Even after a couple of start attempts.)

Now granted, i left the lights on when working on the van the other day which may have run it down....

I checked all connections on the battery, cleaning off the pos & neg, (they appeared clean anyway.) I also checked & cleaned the earth strap connection on the inner wing, but when tightening the nut on the connection to chassis the bolt sticking out the inner wing it connects to sheared off...! So i connected to another bolt point further back, just under where the loom comes through the bulkhead..

Van still wouldn't start. (Though the voltage on my gauge was a little higher when i tuned the ignition on.)
After jump starting the van, it seams to charge OK from the battery & on my volt gauge...

(I don't have a LB or winter pack set up.)

Its been back to starting on the button since.. However i just need to check a couple of things out...?!!

[Northern Bongolow]

ive had a quick look jamie on chells, and i too cannot see where the second earth goes, it looks to head towards the starter motor, and as geoff is on hols,this would be my best guess as the positive must go through the controlling/ start circuits, then maybe this is the earth back dirrect to the battery, maybe.

[jaylee]

ive had a quick look jamie on chells, and i too cannot see where the second earth goes, it looks to head towards the starter motor, and as geoff is on hols,this would be my best guess as the positive must go through the controlling/ start circuits, then maybe this is the earth back dirrect to the battery, maybe.

Ady, now you got me thinking... Engine earth to chassis?? http://lushprojects.com/bongopartsmk2/c ... mgno=.html
So maybe it grounds to chassis anything off the engine??!

It's also worth or not worth adding that the little green indicator at the top of the battery was all good too!

Earth fault the culprit? 16 year old earth strap breaking down??


Edit; Mmmm, now i'm reading somewhere that a dodgy/dislocated earth strap could result in a fried alternator...!!?

[missfixit70]

Dodgy earth straps can cause all sorts of issues, what is the output of your alternator on tickover? Should be between 13.8 & 14.6v. I usually measure across the starter battery, then you can see what's going into it.
Did you scrape the paint back to get a good contact on your new earth?

[Northern Bongolow]

dont think so j, im looking through the manual but cannot see anything. maybe the lushies will help, but i cannot view.

[jaylee]

Dodgy earth straps can cause all sorts of issues, what is the output of your alternator on tickover? Should be between 13.8 & 14.6v. I usually measure across the starter battery, then you can see what's going into it.
Did you scrape the paint back to get a good contact on your new earth?

I can well believe it Kirsty, the reason i'd had my lights on was because i had a couple of relatively new leds blow & was replacing them... Two of which fitted a good year apart, one only a few weeks back... It may also explain a couple of other anomaly's i've been having for a while....


About 14.5 off my meter & the gauge @ 750rpm idle The gauge reads about the same, possibly rising a little on the gauge occasionally when revved to 1500rpm.. Just been out in it for provisions, after letting it stand for the day. (Walk to work.) It started straight up!!


Scaping paint?!! I cleaned the end contact, the inside of the eye for the bolt, the bolt & inside the bolt-head where it contacts the contact... My lights seem to be alot brighter too!

I'm just throwing this idea out there!
I'm not sure if the original, or indeed the new earth point i found for the strap on the inner wing, is a reliable place to earth a battery.... (I would have gone for a solid point on the vehicles actual chassis.)
I have time on my hands tomorrow so shall be measuring resistance....

[wonkanoby]

would have thought starter gets its earthing for the one on the engine from the chassis

recall a good few years back my vw work van suddenly would not start

and it was the earth strap to engine had broken clean off

[Northern Bongolow]

whatever it is my winterpack motor doesnt have it.
i thought it may be on the willinton side but chells does have a split charge system and 2 batteries, but its not a willinton kit,and she has this earth .
come on j , get wet and get under .

[jaylee]

whatever it is my winterpack motor doesnt have it.
i thought it may be on the willinton side but chells does have a split charge system and 2 batteries, but its not a willinton kit,and she has this earth .
come on j , get wet and get under .

Had a little bit of impromptu business this morning but i'm on the case now!!

But first i have discovered something since doing the earth strap in the wing that may interest you Ady?
Just going out for a "bat" up some steep hills to double check!

[Northern Bongolow]

come on then dont keep me in suspenders