Suzuki 2 Strokes

Sorry for a late reply on this Eddie, if you are taking the motor out then you can simply drill the the bush centre from inside the cases and tap it to 6mm x 1.00
The crankcase is 6mm thick and so the standard grub screw will not touch the pump shaft if its only 5mm tall and screwed in flush on the top of the case.

Hi Allan, Used your modification on my 73 cases and it worked a treat, i drilled slightly off centre, maybe i measured wrong heres some photos cheers Neil

Sorry for a delayed reply on this and thanks for posting up the photos.

Going to replace my 77 pump this weekend.
Question
When hard to remove from the bottom using sliding hammer, can you heat the case first then pull out?
Once cleaned inside and the O rings lubed how hard is it to insert back in? light taps or push in?

Ian

T350guy wrote:Once cleaned inside and the O rings lubed how hard is it to insert back in? light taps or push in?

Snug - and don't forget its keyed eh ? So you have to be sure you align the notch in the top so that it seats properly.

Success . Old pump came out with ease using the sliding hammer..pump looks new yet.
Clean gasket area, clean inside, lube O rings and it just slides in, turn pump by hand until it pump notch hits the locating pin , Tap home using a socket that fits the pump.
Heck even the impeller came off with ease..Guess I was lucky.

I used this method successfully, so thanks Alan. My hole was bang on central using the template, so I'm happy.

I know Alan recommends tapping the hole and using a 6mm grub screw to close the hole afterwards, and I understand that there is limited clearance above the hole between casing and the starter, but I am using a slightly different solution.

The push in allen screw covers you can buy to "finish" off allen screws are designed to be a push fit in the hole for a 5mm allen key. That's a 5mm hex across flats. After using Alan's method you have a 5mm hole in the casing - very slightly smaller than a 5mm hex. One of these allen screw covers is a very snug and secure fit in the 5mm hole. They are plastic, so even if part of one were to drop into the gearbox it isn't going to do any damage - whereas if you forget to loctite a grub screw it just might. The head of these things is generally quite thin. I have fitted a chrome one, and can confirm that one pressed into place it is a very firm fit, and clears the starter no problem. With the starter in place there is no risk of this "popping out" of the hole - it is effectively trapped in place - and in any event the gearbox isn't pressurised, so there is no reason why it would pop out anyway.

I'm happy that the allen screw cover seals the hole with zero risk of anything getting in to the case, and have decided not to bother tapping the hole.