Convert curioisities

Technical Big Block Tonti and Loop Frame models
1

I’m currently dismantling a 1976(?) Convert with a rather chequered history - it’s going to be a thorough job, but not a restoration to any recognisably stock form.

The bike is currently fitted with four of these things -
L1040420.JPG
There is one of each in the sump, the gearbox, the bevel box and even the ATF reservoir - fitted into a soldered-on stub. They have fine threads and the remains of a wire to the terminal on the top. Inner end is flat and closed - they look like solid brass, but probably aren’t. These are new to me - does anyone know what they are? Judging by the position I’d guess they might be oil level warning sensors, but I can’t tell how they work. More pics in location:
L1040422.JPG
L1040424.JPG
On the last one you can also see a sump extension with a small canister on an angled stub - could be a pressure regulator of some sort?? (Ignore the bright thing at the top of the pic - it’s just the end of the engine breather tube.)

I’m not too concerned about these - I do not intend to reuse them, and will probably just plug the holes, but I’d really like to know what the rationale/history is. The whole setup seems to have been fitted quite professionally - is it a good amateur engineer with a paranoid attitude to oil levels, or actually a fitment for some particular purpose? Anyone know?

2

Top picture looks more a temperature sensor to me. Never had a Convert so don’t know if they are usual.

3

Of course - temperature sensors - makes sense. Maybe that implies this has been used as some kind of test machine?

Hmmm - it’s probably a good job I’m taking the whole thing completely to pieces to check everything!

4

Does the cylinder contain an external filter or is it a sludge trap? It could have a magnet in it to take metal filings out of the oil? The other bits look like oil temp probes and not level gauges to me as well.

5

The one in the sump looks to be too low for a level switch, they could be temperature or pressure?

6

The can on the sump looks like an oil pressure sender I had for an electrically operated gauge I had fitted to a car.

7

I have a Haynes manual that covers the Convert, and don’t recognise any of them, reckon they’re custom mods by a previous owner!

8

I’ve owned a Convert for almost 30 years and never seen stuff like this. It’s not come from the USA by any chance has it?
Al.

9

Thanks for all your suggestions, folks - interesting stuff. I can’t find any mention of this sort of thing in any of the manuals or parts lists I’ve managed to get my hands on, either.

If the canister is an oil pressure sender it would make sense with the temperature probes if someone has been doing testing. There is no external filter.

Yes, the bike has come from the States, but it wasn’t imported by me, and has been mucked about with in this country since (some of the modifications to the wiring loom are definitely not of the same standard as the engineering adaptations!). I suspect I have not received all the paperwork, but there is import documentation from Florida - why do you ask? Idea?

I got the impression when I bought the bike that somebody had taken two Converts to make a good one, and I got the leftovers, but it may be more complicated than that.

10

USA because I’ve seen some weird adaptations to conform to California emission regs, all sorts of catchment canisters on breathers etc.
Al.

11

The cannister shaped thing is an oil pressure switch. The rest are oil/water temperature sensors. I reckon somebody was experimenting with different types/grades of auto transmission fluids and needed some way of monitoring pressure to temp values within the system.

12

Or paranoid about lubrication!

13

I think Julian may well be right - it would be interesting to see the results of the tests, but I have no way of contacting anyone.

However - it is all making me a little bit paranoid about what I’m going to find inside…