Club 80-90 Forums

Ages back i found this link in a thread:-

http://volksweb.relitech.com/90alt.htm" onclick="window.open(this.href);return false;

Its basicly saying a golf alternator fits an early watercooled T25 engine.



My questions are:-

will this fit an aircool engine?

Is the golf in question a mark 1?


My alternator is fine but the puny 40 amps can't handle the load i ask of it.

Radio
Engine
Fridge
Leisure battery
Headlights

The voltage drops when running and the wrong combination of the above is on. I can run all but fridge or all but lights but not all together.

Has no one else needed a bigger alternator before?

Yes I did this but you will need to swap part of the alloy casting over to accommodate the mounting for the extra pulley mounted fan. Fiddly but basic engineering...

Think you have a problem. That lot is about 25amps a standard alternator would cover that easily and have enough for the wipers and charging the battery. Check all the connections and that the drive belt is tight. Then check the alternator charging voltage with just the engine running it should be between 13.8 and 14.2 volts if it's below that change the voltage regulator.

Some aircooleds were fitted with a 65amp alt anyway - just try and get hold of one of them. The sticker is blue rather than green on the 40 ampers as far as I recall. I might still have a spare somewhere if you wanted to try it...

I have a CU motor with a 65amp alternator fitted
no help I konw but they are out there

bigherb wrote:Think you have a problem. That lot is about 25amps a standard alternator would cover that easily and have enough for the wipers and charging the battery. Check all the connections and that the drive belt is tight. Then check the alternator charging voltage with just the engine running it should be between 13.8 and 14.2 volts if it's below that change the voltage regulator.

Hi, I changed the regulator about 2 month ago (was 13.6 now 14.4). We had an issue before where the fridge was flattening the main battery on long runs as the alt wasn't keeping up.



Belts are fine and earths have been checked. I've even checked for leakage on the + from the alt.


The leisure battery was near dead when i last checked the setup. Maybe that was sucking up to much juice.

You could here the relay swith off and on every 2 seconds once i'd put the headlight on...

Not sure what power the frigde is drawing. Its not a VW standard jobby.

cumbriankeith wrote:Yes I did this but you will need to swap part of the alloy casting over to accommodate the mounting for the extra pulley mounted fan. Fiddly but basic engineering...

This was the mk1 alt? I'll give it a look.

Fiddly? Care to elaborate a little?

Fiddly in that you have to dismantle the fan/pulley off the shaft - might need a puller. Then hope you can get the long bolts out that hold the main casing together, then hope the bearing will slide off the shaft over any corrosion, then hope the air cooled casing does actually fit exactly the same and put it all back together with all the right tolerances so it spins nicely and the pulley/fan bits are still in the right place.

The_blue wrote:

bigherb wrote:Think you have a problem. That lot is about 25amps a standard alternator would cover that easily and have enough for the wipers and charging the battery. Check all the connections and that the drive belt is tight. Then check the alternator charging voltage with just the engine running it should be between 13.8 and 14.2 volts if it's below that change the voltage regulator.

The leisure battery was near dead when i last checked the setup. Maybe that was sucking up to much juice.

You could here the relay swith off and on every 2 seconds once i'd put the headlight on...

Not sure what power the frigde is drawing. Its not a VW standard jobby.

Sounds like you have a voltage sensing split charge relay and the cut in voltage is set to high.

Correct, it is but i've screwed it as low as in can without ity being on all the time.

Have a bob Down A38 Chris

Got 2 spare CU Alts Here for you to Try

Thanks Matt! 40's or 60's?


Just watching a cheap 90 amp on the bay. Might pick it up just have a try