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Technical Area > Engine Related Items

Supercharger Belt


John - You may not remember me, but you and your wife stopped by my shop way back in the 1980s on a return trip from a Florida event. I followed your services back then, but recently I think you mentioned retiring. I will be hitting 76 this year, but I feel as if I was 60. But the new cars have far exceeded my brain capacity with its technology. So, I sold my shop in 1993 and got out of the business. I was burnt out. Real estate business looked much more appealing. Anyway, I did manage to hold on to three of my MGs and they have been stored away in a garage which is air conditioned and heated. That did a good job maintaining the cars. I have recovered enough to try and get these cars back on the road.

My question to you is concerning my 1980 Limited which has the Leyland factory air conditioning installed made for the 75-80 Bs. I am looking at the Moss Motors supercharger for that model and I need a little advice if you can help me with that. I have corresponded with Moss several times and they are limited in there tech help as they no longer supply the A/C they sold for the 62-76 cars with supercharger, kit #363-405. So, not being able to get parts either, I have decided the best route is to leave my A/C and alternator belts alone, (which are driven from the water pump pulley), and install their latest kit made for the 75-80 supercharger #150-070. It seems all I have to do is find the correct length belt since I wont be incorporating the alternator as the kit provides. However, that leaves me with not having the ability to adjust the supercharger belt. Can you suggest a fix for that? My though is to find a way to have one of the two idler pulleys made to be adjustable.

Any advice concerning how I may work this out would be greatly appreciated.

Luke Snyder

A:   I distinctly remember visiting your shop with Caroline, probably in the winter of 1984.  As I remember you were at 1342 (or some variation of the firing order of the MGB) Hill Street.  You had the Irishman working for you.  I believe he came to a technical seminar the next year.

I did retire.  When my wife died in 2010 I tried to continue with my son as a partner and then with my new wife as a partner.  I was not successful in finding a new working relationship.  Add to that the frustrations of low quality parts and I, too, burned out.  But, Im now touring and lecturing.  In fact, I just gave a seminar a couple of months ago north of Charlotte in the suburb of Denver.
On to your problem.

I have a concern about running so much from the water pump pulley.  That shaft is not very large in diameter (what?  7/16) and you have a lot of load on it.  If you can balance the pull in those several directions, then it might be OK, but loaded that pump heavily in one direction wont work well in the long run.  You can modify that tensioner to take up the slack, Im sure, with some sort of turnbuckle arrangement.

John Twist
University Motors Online


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