Next on the list for the 1973 GT750 project, was to get a set of usable carburettors. I had bits for five and a half carb’s, but they are ‘handed’ in the sense that the left side carb has a different throttle slide than do the middle and right ones, plus of course the middle carb is jetted differently from the outside two. Right off the bat, I had a problem as when I looked at what I had carefully, I found that a couple of the bodies were damaged or had been modified – for example the throttle slide stop screw on one had evidently been lost at some point, and replaced with a Robertson headed machine screw !
Each carburettor body is stamped on the engine block side with a (very) small L,M or R to show where they go. Of the six bodies I had, four were usable and luckily the one of them was a ‘left’, two were right and one was a middle. So far, so good.
When I checked the spring lengths I found they were a mishmash of lengths – I suspect it likely that the shorter ones came from 1972J GT750’s as the 1973K had a different, taller, cap than did the J and so also had a shorter spring. At any rate, after carefully checking through all the bits and pieces I felt lucky to have enough bits to build three carb’s .
I had picked up an ultrasonic cleaner from Harbor Freight on our last trip into Montana – this particular unit was large enough that I could fully immerse a carburettor and it did a really nice job. I used a small amount of malt vinegar with some Simple Green and water. After a couple of heated four minute cycles, the carburettors came out spotless. After a rinse in clean water, and a blow out with some carburettor cleaner of the smaller passageways and then an air hose, I was good to go.
I used a carburettor repair kit from Japan – really all I wanted was the gaskets and it was the cheapest way to get them – I re-used the jets and the needle as there were no signs of wear at all on the ones I kept. I suppose we will find out soon enough if that was a smart idea or not !