3.8 dynamo conversion

[swindler]

Hi all

I'm going to fit a Stealth Dynamator. My car is positive earth currently with the original Lucas C42 alternator. I have a couple of questions I was hoping someone who's done this conversion might know the answer to:

1. Should i swap the ammeter for a volt meter? I notice 4.2s still have an ammeter
2. Will my existing loom (Dynamator to battery esp) cope?
3. Powerspark, who sold me the kit, say I can happily use the existing pulley. Does that sound right? The main reason for wanting to do this is so that I don't lose my fan when idling in traffic with lights on.
4. Is there a good, discreet, spot to site the relay - behind the dash dials?

Many thanks!
Mark

[abowie]

1. I would.
2. The wire to the battery is pretty heavy gauge so it should be fine.
3. If they say it's OK it should be fine. It's all about the speed the alternator needs to be driven at and using the existing pulley means you can use the standard fanbelt.
4. What do the manufacturer suggest?

[MarkRado]

Hi Mark, I did exactly this conversion.
No need to convert to a voltmeter
wire gauge and loom is ok (I left the RB340 control box in place using it as a connector block, but removed the innards)
pulley fits perfectly
relay does indeed fit easily behind the dash panel

I took the opportunity and converted to the front lights relay as well as the ignition switch relay upgrades to bring the electrics to a more modern standard.

[rswaffie]

Hi Mark
I have replaced my +ve 3.8 c42 for a Powerlite Dynalite.
The advice from their people was as follows:

1. Pulley should be 2:1 ratio. My c42 wasn’t so replaced it with a billet alloy version from Holdens. I retained the original fan.
2. Cable from Dynator to battery should be rated to 40a. I upgraded mine from the lower rated cable in the auto sparks loom. Probably not necessary, but did it anyway.
3. Powerlite provide a dummy rb340 that has no internal regulator elements, just a 40a fuse to protect circuits. Again,you don’t have to have this as you can adapt the existing item. I used their dummy version.
4. The relay can be sited anywhere behind the dash - mine is held by one of the dial post thumbscrews.

Depending on your supplier/ model of Dynator - some or all of the above may apply.

[swindler]

Hi so I attempted to tackle this today. The dynamator went on fine and lines up well with old pulley and fan transfered,and the relay behind the dash panel.

however something's gone wrong. When I reconnected the battery the ignition circuit seems fine - you can hear fuel pump, red ignition light illuminates on dash. But when I hit the starter button there's nothing.

When i went round to the dynamator itself it felt warm/hot to touch, which I don't think it should? So i've disconnected the battery again pending a fresh look

any ideas?

Oh the other issue was that in determining which white wire of the three from fuse 6 went to the ignition light, in order to fit the relay, when 2 of the 3 were disconnected the lamp went out. So I think, but i'm not certain i picked the correct one??

Help much appreciated!

Mark

[rswaffie]

Hi
If you’re Dynator is getting hot and the starter is not kicking in, the wiring is wrong somewhere.
Did you get a wiring diagram and fitting instructions with the unit? What changes did it suggest for the rb340?
I had difficulty identifying the ignition lamp white wire initially, so used a multimeter to trace it through. Have you confirmed you’ve got the right one - don’t trace it from the fuse box terminal, disconnect each wire and trace it from the spade.

[rswaffie]

This may help, it’s a checklist provided by Powerlite when I was fitting mine.



If this is too blurry, pm me your email and I’ll send you the pdf.

[swindler]

Brill thanks, I'm going to take another look tomorrow. That's helpful flow diagramme - the relay isn't clicking so I've definitely done something wrong with the wiring!

Daft questions -

1. I'm wiring that relay between fuse 6 and the ignition warning light. I.e. i'm not bypassing the fuse altogether with the relay

2. I'm using the large terminal on the Dynamator for the battery line and the smaller one to the ignition warning lamp (that terminal's marked red). I'm not meant to reverse this because of it being positive earth, am I?

[rswaffie]

Hi,
No, definitely don't reverse the battery feed / ign light connections! The fact that it is a positive earth model of dynator means that there should be no changes to be made in this respect.

If the relay isn't clicking, that's probably where the issue is. The relay should come with two of the connections jumpered for the earth connection, check that these are correct. Did the relay come with the dynator or have you bought one yourself?

I also connected the relay between the warning light and the fuse - so basically when the key is turned, 12v leaves the ign switch via the white wire, passes through the fuse and activates the relay and the warning light glows. As long as the light is on, when you start the car the dynator will be 'excited' and charging should occur, extinguishing the warning light. The other wire from the light goes back to the rb340 w/l terminal and then to the dynamo. With the dynator, if there is an internal regulator, then the w/l wire is connected to either a dummy regulator or a reconfigured rb340 - basically 'direct' from the w/l terminal on the dynator to the w/l.

I don't want to worry you unduly, but with my dynator the instructions were explicit in that if the relay wasn't wired correctly, then turning on the ignition "would result in instant failure of the dynator". And guess what......
Hence me getting hold of the checklist once my repaired one arrived!

[abowie]

If this is too blurry, pm me your email and I’ll send you the pdf.

Could you see if Heuer will put this up in the knowledge base; it might save someone (like me) from frying a Dynator in the future.

[rswaffie]

I'll pm Heuer with the pdf. It would also have been useful if Powerlite and their distributors had had it on their websites or included with the product, rather than having to contact their support people after the fact! Luckily, their lifetime warranty meant it didn't cost me anything to fix, but they made it clear that wiring cock-ups were not normally covered!

[Heuer]

Thanks Richard - I have added to the Forum KB.

[rfs1957]

Bought my own Powerlite at Silverstone this weekend and was very impressed by Michael Hadley the MD.

There is confusion in these posts about the identity of these "dynamo-alternators" - there are several products on the market purporting to be the same thing, and they are NOT all Powerlite, and there are huge differences in price.

Powerlite (parent company EUROLEC) will now in fact buy back - at cost - anyone's Chinese copy (a.k.a. the Dynamator from simonbbc.com) in the form of a discount when you buy one of theirs.

That plus the Lifetime Warranty makes it hard to beat.

I tried to stay Positive Earth to remain a freak, but he didn't have one on the stand, so I'm falling into line.

On such details does the course of history depend.

[swindler]

Andrew, Richard, Mark thanks so much for the pointers and pictures: Success!

Because my ignition lamp white wire was also linked to the white wire that bridges between fuses 6 and 7 I was inadvertently taking power to fuse 7 circuits...including starter button.

Anyway, sorted with a split and everything seems tickedy boo. Bright lights and fast wipers on tickover.

I'll give it a few miles and report back as I know people have been intrigued to see if the dynamator stacks up with other much more expensive versions. I'm hesitiant to recommend until I've given it some use. It certainly looks the part in the car.

Thanks again
Mark

[rswaffie]

Glad you got it sorted

[peters3103]

Hi Mark, how is your Dynamator going? Working well I hope. I’m contemplating fitting one to my 3.8 however my car is already running an alternator fitted by the PO. I’m just wanting a more original look. I figure my wiring should be straight forward enough but will need to source an original dynamo bracket etc. Also the spring loaded tensioner has been removed. Not sure if I’ll need to fit one.

Cheers
Pete

[swindler]

HI Pete, so far so good! But I've only had her out about 4 times since fitting it. But I can now use all the electrical systems at will at idle which is nice.

I still have the spring tensioner and used the original pulley and hence W profile belt.

[peters3103]

Excellent result then. Obviously the spring loaded pulley produces the tension required on the belt whereas my alternator conversion requires the alternator itself to be adjusted.
I’ll need to revert back to the original set-up.
I’ll have the engine out in November so can get a good go at it then while I’ve got access.
Now to find the parts...

Regards
Pete

[Heuer]

Many of us remove the tensioner as it creates noise and is only meant to take up slack due to wear. Jaguar installed it to help make the car more maintenance free, not something that is an issue with enthusiastic owners. Dump it!

[peters3103]

Good advise David, yes just got to reading some other posts on the subject after writing mine and it would seem pointless to go to the trouble of procuring the parts. I’m happy to take care of my own adjustment so to speak. All I should need then is the mounting bracket, adjuster link and associated hardware.

Regards