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+--- Thread: Dynamo swapping (/showthread.php?tid=9088)
Dynamo swapping - Andy Bennett - 29-12-2023
Hi All
On my 33 RP I have a CFR2 cutout and C35M dynamo.
For Christmas I received a rebuilt C35A dynamo.
I have been trying to understand what would need to be done to fit the rebuilt C35A in place of my M and with the CFR2 cutout.
From lots of reading my understanding is that:
Whilst the A and M are mechanically interchangeable there are electrical differences.
My fitted 35M has no inbuilt resistor, with the R in the cut out designating it as having the resisitor inbuilt.
My understanding is that the A had the half charge resistor under a cover on top of the dynamo alongside the field fuse. However, my new rebuilt A does not have a box on top, it just has the 2 insulated terminals. As per this picture:
More reading on the Cornwall site suggests later 35As had the resisitor inside the cut out as per the 35M.
So, to my question. Is my understanding correct, that this is a later 35A and if so can be simply used as a direct placement for my existing 35M/CFR2 with no mods required? Or have I added 2 and 2 to make 35?
Thanks
Andy
RE: Dynamo swapping - Bill Dixon - 29-12-2023
Andy this should be a direct replacement. The red mark should be the D output,the other connection will be the Field out put.
RE: Dynamo swapping - Jeff Taylor - 29-12-2023
Hi Andy,
Just to add that my C35A (I think it's Lucas dated on the outer casing as 35 i.e. 1935 build) just has the two insulated terminals as per your illustration therefore no top box - this is on my very early 1935 dismantled (RP based) AVH Van. Yours looks nicely rebuilt.
Jeff.
RE: Dynamo swapping - Andy Bennett - 30-12-2023
Great thanks both. Whilst not tested visually it looks very good and turns smoothly.
RE: Dynamo swapping - John Mason - 30-12-2023
Hello Andy, just a point to remember. Is the new reconditioned dynamo set to the same polarity as the old one.
John Mason.
RE: Dynamo swapping - Andy Bennett - 30-12-2023
Thanks John and yes both 6v positive earth.
Andy