[slash60]

I have a generic carb which has a misplace fuel inlet nipple. The carb is similiar to an ASP 61 carb. I need to relocate the fuel inlet nipple and tap the hole. Would anybody tell me exactly what size tap I need to use/buy to do this. I do not have a thread gauge.
Tower hobbies list it as 3.5mm thread, .6mm coarse pitch and 3mm length. Would that be right?. I would like to be sure before I buy the tap. Any info would help . Any lead where to buy in ontario, canada besides LHS?

[aceplant00]

go visit someone that does custom machining. They might have the tap. Worth a try.

[bartman]

Amazon

Amazon

[Cougar429]

Can you post a pic of the problem? I looked at what I can find online and cannot see where else that fitting could go.

If I can see what needs to be done and you have patience send me the carb and I can try and do the work here.

NOTE: There was some problems reported on the smaller engines where the inlet port on the HS housing would turn during installation and not align with that fitting. Easier to correct than moving the fitting itself.

[slash60]

Tod, that is my last resort. It's a simple fix (see pics), drill and tap the nipple to the right location and cap the other one with some screw. Brian, thanks for the link, if I cannot find it here anywhere in ontario, then I will buy it for this fix as well as being there when I need that tap size. I knew there was one specifically for the nipple, just did not know exactly what to look for and where.
Gary, lots of thanks for offering to do it. You can see from pic that the placement of the fuel nipple is on the carb body pointed upwards, not the usual pointing towards the the back, crankcase. ( no rotation like the supertigre engine carb h/s needle). Appreciate all you guys input/suggestion, now to look and buy that special tap. Thanks again.

[kip51035]

Check the pressure nipples on your mufflers, you might find one that fits. You can purchase standard 4-40 and 6-32 thread nipples from your local hobby shop.

[slash60]

Thanks cliff for the suggestion, I do have some muffler nipple around and taps of that size in my tap set. Will look into it.

[Cougar429]

Man, that's strange. Looks like someone was having a bad day.

Another option may be to look for another carb with the same base OD and bore diameter. I have swapped carbs from different motors, (usually OS as they are more reliable than a lot of the clones) and think I still have a Perry in spares.

You may also be able to do a safety mod I added to most of my older 2-strokes, fitting a remote HS needle to the back cover and blocking off the original setup. Gets your fingers away from the prop and works exactly as stock, (adjustments react as quickly, as well). Although OS and Fox offer their own versions, I preferred the one from Evolution as they often were a direct fit to the back cover bolt spacing on 40-55 size engines. The only work done was to remove their blue limiter ring.

http://www.amain.com/rc-airplanes/ev...046874a/p33279

OS sells a blocker fitting that replaces the original HS needle. I would have to go into spares to get the number. About $5 if I remember correctly. Most of these carbs shared the same HS fitting thread specs.

Here's one I did to an 80's OS 40FSR.

[slash60]

@gary, yah, I think that guy was daydreaming when he bored/tapped the hole location. Anyways, this was graciously given by a fellow modeller to use if I cannot find some solution to my ST G61 carb problem (which I have not got into retuning yet, but will in another thread) perfect fit, inside and outside diameter hence I am trying to make good use of it.
Your remote needle mod makes sense. I have to know though the dimensions of the back plate bolts if it matches my STG61 backplate. I assume the remote needle will work on the G61. If I cannot solve this relocation problem, this is my next logical step. Thanks again for the input.

[floyd]

Why don't you try to run the motor with the carb the way it is? All 4 Strokes have the inlets facing up. While a 4 Stroke has better fuel draw you'll probably find facing up makes no difference at all on your motor. And if your mounting the engine on it's side then the inlet shouldn't be an issue at all. Cheers Floyd