Dynamo bolts

[Chipperman52]

My TR3 fan belt needs replacing. Got the two bolts undone on the slide easily. BUT we couldn’t access the lower bolts to undo them with sockets and spanners. Any tips please. 

[RobH]

It's a bit awkward to access because the choke mechanism on the carbs, the steering column and the dynamo body all get in the way.  It is do-able, just a fiddle and you have to work by feel and accept that your arm may  suffer a bit.  I found a short combination spanner is easiest as it's less bulky than a socket and ratchet.   

You don't need to loosen either very much. The front bolt is relatively easily accessible from the front and should just unscrew because the pedestal it screws into is captive.

To get to the rear one I reach forward from under the rear carb with my left hand and go beneath both the  choke rod and the steering column. It helps if your arms are longish. In extremis it might help to disconnect the rear end of the choke rod.  If you are lucky the rear bolt might loosen (and re-tighten) enough without needing to hold the other end. 

[Chipperman52]

Thanks RobH

Had a short spanner (due to space) on both bolts but simply couldn't shift them. Perhaps i'm not strong enough!!

Also have noticed the belt fitted is 19 X 975. A spare, that came with the car when I bought it last year, is only 900 and not cogged, doesn't look long enough?

Finding a 19 X 975 is also proving difficult. How critical is this as I can source a 17 X 978 cogged.

[RobH]

I think 900 is the standard belt size but it depends where you are measuring - inside or outside.  If it isn't cogged it will be very stiff and difficult to fit anyway - the standard solid belt is not reckoned to be very good which is one reason many people fit a narrow belt conversion.   As you say modern 19mm belts seem to be very scarce but a 17mm does work OK. It will run deeper in the pulleys and thought there is a fair bit of adjustment on the dynamo, if it is too long you will run out of range. 

I run a 17 mm x 965mm outer, BX section cogged belt with no problems but that is with an alternator with a smaller diameter pulley hence the length is a bit shorter. 

Loosening the dynamo is the first puzzle. The next is getting the new belt over the crank pulley as the clearance between the pulley and the strut brace and steering rod is the real test. You can get a bit wider gap on a sidecreen car by putting the steering on full lock, but that doesn't work if it has been converted to R+P steering.  A 17mm belt certainly helps as they are only 11mm tall in section.  Some people have even resorted to loosening the engine mounts and jacking it up a bit. 

[John McCormack]

If the belt is too tight to get on the pulleys; remove the real bolt and adjusting bolt, loosen the bottom bolt without removing it and you should be able to twist the generator enough to slip the belt over the pulley.

[Chipperman52]

Well what a pig of a job that was!! Think the incredible hulk did up those bottom bolts! So little room to swing a spanner. Never had this problem on my 60's cars back in the 70's when I had just learnt to drive and "spanner"

All done now, fitted the 900 mm belt with little problem. All in a sweltering 30 degrees. Can take it to the local TR meet tomorrow night.

Cheers

 

[Tony_C]

Yep know what you mean, I increasingly find all the ‘5 minute jobs’ from the 1970’s now take half an hour minimum…….

However, you can look forward practicing your smug smile at the meeting when all the members compliment you on the good job done particularly for putting the spare belt already in place for next time?!