dynamo/dynamator

[billyjowett]

has any one changed their dynamo for a dynamator (an alternator but in the dynamo shell complete with rectifer/regulater)
if so how'd it go?
any problems with the wireing/controlbox?
looking forward to hearing your stories

[Keith Clements]

The dynamator is an alternator so is wired as per the diagrams on Jowett.org .
I have run alternators on Jav and Jup for 30 years in the most demanding rally conditions.

[billyjowett]

well, i've ordered a dynamotor (see other post) so will let you know what troubles i encounter

[Keith Clements]

Obviously it is most important to order one of the correct polarity. In the past I have always converted from positive to negative earth when fitting an alternator.
But now both polarities are available. I actually have one but have not fitted it as it did not come with the tacho take off which is what I had ordered. They are now available so am returning it for the correct one.
They are made in China so may not be as reliable as a European one, although Lucas did not have a good reputation according to the Americans et al.
Like all alternators you have to make sure the battery circuit is in good nick. A bad terminal or earth can quickly blow up the electronics in the regulator. The open circuit voltage builds up at quite low revs. Dynamos/ Lucas regulator box are much more forgiving.

One thing you will need is a 40 Amp fuse holder to protect the dynamator from overload. Many have fitted it inside the shell of a Lucas regulator box so that it looks original. Do a Google ... If you retain the 35A fuse it will blow due to the increased output.

As I said, if the fuse goes, do not run the engine as you will blow the unit up.

[billyjowett]

in the motocycle world lucas was always know as the prince of darkness, what with 6v lighting ect.
but , yea, going to run a new charging circit anyway. i really don't want to make anything else worse. i've done enough of that this week

[billyjowett]

well, i have all the things i need (i think)
of course, having to use the ignition warning light in a closed curcit has caused a couple of moments head scratching (as the holder earths the bulb)
i've been doing some googling, never a good thing i know.
i seems that the fuse is onlt there to protect the wire (as keith ays, if the fuse goes it'll damage the alternator)
so, am i right to think that if the alternator shorts through then there's nothing left to protect?
in my fiat the charging wire is just a 60amp wire running, un-interupted, to the battery.
am i making a silly decision?

[billyjowett]

well, here goes again, fitted the new donamator. all the wires sorted out.
as some one as been fiddling around before so re wired to original colours.
cant trace some of the wires fron the D on the control box (going to scratch my head 'til i find out what doesn't work)
anyway, she's running to day, and restarts! seems that i now have a bit of trouble with the fuel line so a good over of the fuel tank looks to be in order

[Keith Clements]

It is worth blowing the fuel line back through with compressed air but make sure the cap is open, otherwise your tank might expand.

Also worth checking there are no leaks or flattened parts. It is possible for air to get sucked in around the flexi pipe if it is not tight.

Also worth draining all the old fuel out and putting new in. You can always add the old back in bit by bit or use it as a cleaning agent.

Any rubber in the line may have swelled, so renew it.

[billyjowett]

well, took her for a big run yesterday (21st). had to hand prime the carbs and fuel line, but she started first time and once she was warm, i had no trouble.
left her for about 45 min and she started fine again.
looks like we've cured a few things and now only have to worry about every thing else!!

[Forumadmin]

Peter asked me to convert his Javelin to negative earth. This is the answer..
You may need to scroll around the picture to find it.

[p.p.]

i love you big smile !!!
i'm still over the moon.........