Thanks Chris.

I am not a machinist or engineeer so these suggestions are most useful.

I have a mini butane torch for point-heat application. On further consideration I will make up a circumferential grip along the lines suggested in the MEW article you have kindly provided, before resorting to drifting the insert out.

You should be able to make up a tool like that from some K&S 1/16 (or slightly thicker) brass strip, a drill press, hacksaw and a bit of filing...........on reflection some 1/8 alloy strip might be even better-to give you the maximum gripping area........

ChrisM
'ffkiwi'

Martin,

Good idea to avoid peening the head, so I will give your advice a try. I've used J-B Weld before, with good reselts.

Bill

Got the MK-17 sorted. It starts easily and runs well with the home made venturi insert.

Thanks to Chris for the link to the venturi insert puller.

I don't know about yours but all three of mine have the venturi held in by the needle valve assembly and this need to be removed for it to slip out. Mine interchange very easily.
Max

Test

Mine too. Fiery posted that he had removed the NVA (needle valve assembly) back in post #16. That in mind, the rest of the posts make more sense.

My guess is that a metal burr or a faulty machining had caused the venture to be stuck. They are still great little engines.

George

George is correct. The 'red' insert was held fast by ancient congealed castor oil which had turned to the consistency of badly set toffee. A little heat from a pin-point propane flame spread evenly over the intake tube, a deft twist with a soft jawed 'nutcracker' shaped tool, and out it came.

Engine shown is a super little runner, though the contra is a little 'sticky' when hot. No biggie. No leakage at all, and far better than being too loose. The home made intake at 4 mm diameter worked very well.