1wrangler

My Feedback: (1)

Just picked up a used Saito 125a (my first four stroke) and need some basic help. Also, Ilooked at the owners manual online and found it very generic and unhelpful. First off, I am unsure what the metal barb coming of the crankcase backplate is for. Is this a breather? Does it need a line running somewhere? Also, the high speed needle adjustment screw only adjusts 5 "clicks" before it hits a definite stop (both ways). Seems like that would not be enough adjustment for all altitudes and conditions. Thanks for any help you guys can offer!

Gray Beard

My Feedback: (-1)

A crank case has pressure and that is the vent, just add a piece of fuel line to it so the oil or blow by is vented out the bottom of your plane. The high speed needle should be able to be removed so five clicks out is a problem. That should be a counter clock wise turn to remove it. Clockwise is lean and counter clockwise is richen.

1wrangler

My Feedback: (1)

Thanks Gray Beard, I just hope I can figure out this high speed needle thing. It's really strange.

MinnFlyer

My Feedback: (4)

I wish you had posted sooner, I was just in St Cloud last night.

1wrangler

My Feedback: (1)

Well I took a pliers to the high speed needle and was able to free it up enough to now adjust it with my fingers but it is still more stiff than it should be. I guess I'll keep working it and see how it runs in a few days. Maybe it has been sitting for awhile and is gummed up?

MinnFlyer

My Feedback: (4)

That's possible. Try soaking it in alcohol and maybe taking an alcohol-soaked toothbrush to it.

PS, don't use YOUR toothbrush, use your mother-in-law's

1wrangler

My Feedback: (1)

LOL! Can Iremove the whole carb and soak it in alcohol? Will any damage any components in the carb? Thanks guys!

Gray Beard

My Feedback: (-1)

Alcohol is just fine and my guess would be it had been run then boxed. The castor oil gums up and freezes up parts. Before you do anything you should use your covering heat gun or your wife's hair dryer and heat it up and get everything freed up. The fuel is just alcohol and oil with some nitro so just plain old alcohol isn't going to harm anything. Heat is your friend when you have a gummed up engine.

dropstick

My Feedback: (2)

sorry to interupt but i have a saito 125 and im trying to figure out what the hole is in the middle of the front of the cam gear housing. first 4 stroke dumb ?

adambarker

rebuilding my saito 125a , can anyone tell me how to line up the cam with the crank? i can see the dot on the cam but can't tell what to align it too , any help thanks

Gray Beard

My Feedback: (-1)

Piston at TDC and cam dot at 6 oclock bottom of the case. That's off the top of my head, I don't work on Saitos often, OS for the mostg part. John Buckne is my go to guy on Saitos if I have a question.

daveopam

My Feedback: (9)

Thats not a hole in the cam cover. It's a set screw.
Gray Beard is right about setting the timing. Get the piston at TDC and make the mark straight down. You can also remove a lifter and put a pushrod in the hole in the cam to hold it straight. It's not really needed though. It's an easy task to get it set. You can check the timing after assembly as follows. With the back cover and rocker covers off. Rotate the crank until both valves are slightly open. At this point the piston should be at TDC.

BTW Gray Beard, hope you are doing well. It's good to see you back.

david

Gray Beard

My Feedback: (-1)

Thanks Dave, the hart problems are doing fine, Or so they tell me. As I recall the Saito has no TDC mark on the thrust washer, sorry, this is all off the top of my head, I haven't any Saitos on hand to look. Anyway, if so then it's a good idea once you find true TDC and the dwell, that little movement in the crank where the crank can be moved back and forth a little and the valves don't move, to mark the thrust washer with a line at the center directly in front of the case center casting mark. This is done for you on the OS engines. It just makes finding true TDC easier from then on. Just an FYI. That timing mark is on most engines but it is either Saito or YS that doesn't have it.