Need help with tuning

[HDClown]

I have a Raytek MT4 with laser dot. I was trying to use it to tune my engine today but I was getting readings all over the place . If I read down the head and put the dot on the glow plug and it was always low. Like 150F.

If I read outside the heat between all the fins it went from lows 100's all the way to 300F.

I need a process. I know it's all about balance between low and high but where do I start? If I take my engine where it is right now and tune to temp/smoke with high needle, how do I know if that is correct? My low needle could be all wacked whcih is effecting the high, correct? I reset the carb to stock a week ago and then just leaned out 1/4 tune both high and low, but then I was still way rich (spewing fuel out the pipe) so I leaned out some more. I get good white smoke at WOT. Low end seems weak but my clutch may be slipping as well.

Where do I start with the needles themselves? Should I reset back to stock carb settings and then tune the high to temp? Start with where I am? This is where I get confused.

Then I'm confused with tuning the low. I see some posts about tuning the high, then tuning the low and the way to test the low is to do short runs where you slam the throttle but don't drive very far, then tune the low. But then when I do longer WOT runs, won't my high be out of wack?

It all seems very confusing and I havn't read a post or article that makes sense of it all yet.

[BWild97]

The best place to take a temp reading with the infrared unit is to point it down at the base of the glow plug. If the engine will idle and stay running then your LSN is not too far off but to be sure you should set it to factory settings then start the engine, if it starts and idles ok then you can start to tune the HSN, if not then turn the idle up with the idle set screw. Don't allow the the gap to exceed 1.5mm and make sure the slide is opening and closing all the way (check by pushing on the breaks). If turning the idle set screw CW doesn't allow for an idle then turn the LSN CW 90 deg or 1/4 of a turn at a time untill it will idle! Remember that this is a SLIDE CARB and once you start to tune the LSN the idle set screw will play tricks on you, at the point when the LSN starts to lean the idle mixtuer the engine rpms will increase, if you try to lower the rpms with the idle set screw you will cause the idle mixture to become even leaner while you try to reduce the idle speed resulting a higher idle speed than desierd. So remember to richen the LSN 1/8 of a turn befor you try to set the idle speed. Now check the the idle mixtuer by pinching the fuel line near the inlet niple you should get about 2-3 seconds befor the engine revs up and dies, if the engine does not rev up and die after 2-3 sec. and just dies then your idle mixtuer is too lean, turn the LSN CCW 45 deg or 1/8 of a turn and recheck. By now your engine should be performing pretty well

Oh, by the way optimal running temps for most engines are 212-280 deg F. And if your HSN is set too lean then so is your LSN, the HSN is the master fuel adjustment!! Also keep in mind that you shouldn't set the HSN to a specific temp, just try to stay with in the safe zone!!

Good luck, I hope this was of some help!!

L8R, Bill W.