Leccy Problem?

[rikisha9]

Hi folks

Ive got a 1984 t25 panel van, 1.9 petrol, watercooled

I have done this twice, installed fully charged battery, got engine ticking over until warmed-up
set idle speed etc and all seems ok to set off up the road.

Drive up the road for quarter mile and the engine dies and the battery is gutted.

My garage bloke said that he thought the alternator was faulty, then folks on here were saying
what about the regulator...

so i have had the alternator/regulator tested at an auto-electricians who say that the unit is sound and
delivers 13.9 volts...

but... the bloke at autoleccy also said that the small spade connector is a lead to an indicator bulb
on the dashboard and if the bulb is gone then the alternator will not charge the battery, this wire
i hear is the blue one, someone else i met also said that this circuit may involve the control box.

Please can anyone suggest any ideas about this problem

bestall, rik

[VWCamperfan]

The alternator requires an external excitation voltage to kick it into life. This is commonly sourced from the charging indicator lamp. Check to see if yours comes on when ignition is turned on.
Your best way to check for charging is to use a multimeter connected to the battery. Check voltage when engine turned off and check voltage when engine turned on and running. Should be somewhere near 12-13 volts when engine off and near to 14 volts when running.
Your battery shouldn't be loosing power over such a short distance. Most vehicles will run for miles without an alternator charging them.
How was your alternator tested by the way?

[rikisha9]

hi camperfan

thanks for input, sounds like there could be an issue with using admittedly weak batteries...

but the excitation/initiator impulse may well be the thing to check

i am also working on a float chamber theory as the fuel system had a water contamination issue
a while ago, this has been improved but a needle valve could be sticking

a for the alternator test, an expert took it to a back room and clamped it to a machine i could
hear running for about 5 minutes, he came backed and told me the unit checked out at 13.9v

best, rik

[VWCamperfan]

Thought it may have been taken out to check it! Check it while in the vehicle now as I described above, should give you a better idea of whats going on. The alternator is ok, we know that but you need to check the cables that run from the alternator to the starter motor post and ensure the bolts securing the alternator are secure for a good earth.
The cable from starter motor to battery should be ok because you can start the engine without trouble (I presume). Just mentioned that because that is the cable that takes the charge the rest of the way to the battery.

[rikisha9]

hi mark

yes, forgot to say i had the unit out, so now will re-install it and get to a meter test
as you suggest, seems like a classic autoleccy problem, tracing circuits etc which i dread
because ive not got the skills, will give it a go!

any more input from others on here welcome

will post back later

many thanks, rik

[rikisha9]

hi folks

cant believe how far back i had to go to find this, a week or two is a long time in t25 land of
tech probs, anyhow..

said i would post back....

installed alternator and unwrapped a clot of red insulation tape and found a very bad join
where two red pvc wires from alt via plastic block were joined to two old red perishy rubber wires
leading to front of van. tidied up and reconnected with crimp connectors, alternator then charging
at 13+volts, ok.

laterly found fuel line restricted/blocked causing float chamber to empty after quater mile

i fixed my own van!!!

garage bloke had it for 10 months, he let me use his airline to blow out
fueline, he gave me an inline filter, i think he was trying to get me off my butt, it worked!

needs a new battery but van goes great

thanks for all advice about testing, caution and saving money from the expertise on here

best, rik

[VWCamperfan]

Glad you got it sorted... Well done!