Is there any information available on how to test a Lucas Australian 8TR Voltage Regulator?
Maybe some one is an Auto Electrician and could share some advise - would be much appreciated.

I have some lucas manuals here and I am sure 1 contains info on testing the TR units. I will have a look and get back.

_________________
Cheers Dave.

Cheers much appreciated - Many thanks

As I suspected earlier the testing procedure for the regulators is carried out using an alternator test rig, or alternatively on the vehicle. This is due to them being dependant on current draw as well as voltage level.
You could test on the car but obviously depends on having a known good and working alternator.
I have a test rig here and while it is not specifically set up for the 4 wire regulators It would not take me long to adapt it.
If you wanted to send them to me I could test them for you, time would be dependant on the shed temperature and as we hve near 40C for the near future it wont be this or next week.
Hope this helps (probably not.)

_________________
Cheers Dave.

There's some information and documentation in this thread, including a basic test procedure for the later 4TR regulator. Being a straight swap for the 8TR I suspect the process would be the same when testing the 8TR.

viewtopic.php?f=2&t=101068

_________________
ex-NSW Police 1970 MK II Cooper S
VMCI #43

Thanks Steam and winabbey for sharing the information on the 8TR and 4TR.

So now my question being - Is the 4TR an original factory part (voltage regulator) fitted to the Mk 2 Australian cooper s? or should it be a 8TR from the factory? or did they have more than one supplier - one who used the 4TR?

I've had the cooper s for a number of years and the 4TR was in place when I purchased it and interesting that winabbeys Mk 2 is the same with using the 4TR

I will still need to test the 8TR but sounds like I will need to fit it in place to achieve that.

What would your thoughts be about factory fitment for the MK 2 as all the Mk 1's Ive seen appear to have the 8TR.

They were fitted with the 8TR. The 4TR was the replacement if there were no 8TRs available

Just thought I would add my 2 cents worth. My 1969 Mk2 was fitted with a 4TR.

Thanks Cooperess for your reply.

gtogreen1969: Did they use the 4TR for factory assembly if the 8TR was not available at the time or was the 4TR fitted after assembly if the 8TR failed later in life and the 8TR was out of stock or no longer available on the local market?

And my 3/70 Mini Matic had the 4TR.

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

domini in aust: Thanks for your reply.

It's almost like the 4TR could off been fitted at the factory? - early 1970?

I could live with the 4TR but should it be the 8TR -

My understanding is that the 8TR (Lucas part 62938104) was fitted initially to all MK II Series Minis.

By the time the Clubman range was released it appears the 4TR (Lucas part 37527) was being fitted. The 15AC alternator was then replaced with the 15ACR with internal regulator.

So somewhere in between all that was a change in production.

The 4TR would have been the preferred choice as a spare part when 8TR's failed.

The round-nose part book PUB1012 shows the 4TR but no date of this update.



A Parts Amendment Advice lists the 8TR for all MK II vehicles.



The Clubman parts book PUB1052 shows the 4TR.




Some under bonnet photos of early advertising and press cars might assist.

_________________
ex-NSW Police 1970 MK II Cooper S
VMCI #43

My experience supports winabbey's comments. My mini K had the 8TR from factory, but it failed some time in the 1970s. The only available option was the 4TR, which has been in the car since ever since. Its part number was painted and has disappeared over time.
Incidentally, the mounting holes in the inner guard are identical for both.

My 1970 S still has its original 8TR.

Lucas Australia was still making the 8TR at least until May 1971.

_________________
ex-NSW Police 1970 MK II Cooper S
VMCI #43

Not all 4tr units are the same, the original was a 3 terminal unit for use with 10 and 11ac alternators.
A redesigned 4tr with the part number 37527 was produced for the 15 and 16 ac series alternators. This is a 4 terminal device with the connections being the same as the 8tr. The 3 pin was adjustable, the 4 pin is not.
The 8tr was described as a thick film design.

_________________
Cheers Dave.