spaceworm

Hole in pickup tube at the 1/4 tank mark? Sucks air when the fuel level gets to the hole? Just a thought. Another thought: Maybe the clunk is stuck in the tank at the 1/4 tank level? Again, sucking air after that. Good luck. Sucks to suck air instead of fuel.
Sincerely, Richard
AMA 861960
Club Saito #635; Saito 56, 100, 120abc, 130T, 180

Jim Branaum

My Feedback: (3)

I am assuming this is at all throttle setting. If so, this is probably the problem. Test it by pulling the cowl so you can watch the fuel flow. Watch for bubbles as it approaches 1/4 tank. If it only quits as some, look at what George Aldrich taught me.

Rudolph Hart

Try tuning it on the ground with a small load of fuel,that's where it's cutting out in flight my guess is you'll go at least three clicks richer.

Rudolph Hart

Sad to hear richard and my condolences to you and yours...just try to remember that there is always someone who has a bigger problem.Mine's nitro

acdii

Clunk and lines all checked out, that was my first though too. I will try the tuning with 1/4 tank instead of half tank and see if that helps. OTOH just wondering it my AOA had caused it by leaving the clunk high and dry. I was in a steep diving bank just before it quit, so maybe it had sucked in air just before leveling out. I wasn't going very fast either, so who knows. I thought it ran out of fuel, when I picked it up it looked like it was empty, but when I put it on the stand and lifted the tail level the fuel was over the clunk, just barely. The clunk is the brass type with a inverted cone towards the opening so it sits a bit taller in the tank. Maybe thats the problem.

FlyerInOKC

My Feedback: (6)

Stupid question are you using the muffler nipple to pressurize the tank?

Jim Branaum

My Feedback: (3)

It may be a clunk problem. There are 2 types of clunks I prefer, one for gas and one for glow. For gas, I get small lawn mower clunks and use them as the attached fabric type of filter will mop up the very last dregs of the gasoline. For glow I tend to do things like sintered brass clunks I also set my tanks slightly nose high.

YMMV

acdii

Yep, using muffler pressure. The one thing different on this one from all my other tank setups, I am using the filler valve from DuBro, mounted at the bottom of the firewall on my Cub. think I will change out the clunk next time its in my shop for maintenance.

Rudolph Hart

[QUOTE=FlyerInOKC;12094531]Stupid question are you using the muffler nipple to pressurize the tank?[/QUOTE

It's ok not to,just richen the main needle a bit,lsn will stay the same.

Acdc next time you have an engine on the bench make sure the fuel tank is easy to move around while the engine is running,you'll be surprised

rickj

My Feedback: (213)

I have been working on a friends Saito 150 and I am lost. The engines runs great, good top end with a very good idle. The transition from low to high is right on.
The problem is as you open the carb there is a fine mist of fuel coming out and the more it opens the greater the mist gets. I had the carb apart and no problems
found. I checked the tank and lines, no problems found. No air leaks. This just started and until now the engine has been running super. I have not checked the
valves and that is where I am going next. Any help would be greatly appreciated.

Thanks,
Rick
.

Cougar429

My Feedback: (3)

Do you have the carb inlet extension installed? My 150 had the organ pipe which was supposed to minimize spitting.

spaceworm

What he said. Here is my FA-180 with intake trumpet:



Here is the trumpet before installation to the carb inlet (shown inverted):


FA-150 similar, maybe the same part number.

BTW, I almost lost two fingers, and certainly my nerve, hand starting a new 150. It kicked back and actually cut partially through a heavy leather glove I treated it with much more respect after that, and used an electric starter, making sure the prop safety nuts were securely tightened. Good luck.
Sincerely, Richard
AMA 861960
Club Saito #635; Saito 56, 100, 120abc, 130T, 180
YS F 120

rickj

My Feedback: (213)

Thanks for the replies. The engine dose not have the trumpet. Until now no problems.
I will have him order one to see if this helps. Also I forgot to mention that the engine is inverted.

Thanks, Rick

rickj

My Feedback: (213)

Richard, sorry to hear about your glove and happy to hear you still have all of your fingers. I have used
4 stroke engines for years and I got bit once and now I use a starter even on my 4 stroke 20. Be careful !!!

Thanks, Rick

acdii

Man, yesterday was a crappy day to run an engine. They would not run smoothly at WOT no matter what, must have been the high humidity. We both flew high just in case.

Jim Branaum

My Feedback: (3)

While there is nothing intrinsically wrong with using an electric starter, I have see folks bend the con rod when there was a fuel lock issue. I personally feel it is more effective to learn the proper way to start a 4 stroke engine (no brand mentioned) and to use the right tools - a chicken stick!

Most 4 strokes like to be wet, so I prime them by opening the throttle and flicking (with said chicken stick) through until you see evidence there is fuel in the manifold (usually indicated by dripping from the carburetor). Then I put the glow driver on and use the stick to rotate the prop BACK against compression. I let it sit there for 5 seconds or so and then smartly flick it backwards against that compression. Most of the time they start right there just fine but sometimes with the larger engines they start running backwards. Sometimes that can be corrected by reducing the idle until they pop and start running correctly. If not, pop the throttle or kill the idle on the transmitter and start over again. Remember to take the glow driver off while you are massaging the prop and fuel combination.

YMMV


Chicken sticks FTW!

Rudolph Hart

The cheap ally intake trumpets are well worth the money,cleaner engine bay too.Jim i think the ex handbrake MUST have been a fourstroke,you had to use a chicken stick(taser)with her too.

SrTelemaster150

Maybe your fuel has sucked up some of that humidity.

FNQFLYER

To all I have not forgot about my offer of the Little Red Saito Book. Family life etc intruding into my life has gobbled up lots more time than I would like but I will attend to this matter shortly. Of note only 2 people have responded Spaceworm and Old Fart. OF suggested that I copy / scan it and make it available to all. Don't have the time at the present but will consider same soon. More later

Jim Branaum

My Feedback: (3)

So finally found time to work on the engine problem. Adjusted the valves since one of the guys here suggested that and I always try the easy stuff first. They were off but not by that much. Pulled the carb from the old 150GK and from the newer 150S. When I compared the carbs, I noticed some sort of glue around the threaded part of the needle seat tube and a couple of missing nuts. That made me very suspicious, so I tried an air test. When throttle is closed on the -GK carb, airflow stopped. Not so for the -S carb, so I think that is the problem. I completed the switch and now we have rain in the area so I don't run engines in the rain. If I am lucky I will get to run it Saturday and it will turn 9K.

<off muttering and grumbling about NIB stuff that isn't from RCU folks>

Can I have a little red book?

acdii

It is possible, I didn't drain the tank from my previous flight like I always do, and had a half tank of fuel in it that sat for awhile, and was in my cold basement before it was brought up and stuck on the truck for a few day and it was very humid during that time.

Rudolph Hart

Jim if you can please do some low passes in the rain sometimes heavy,makes the 82 hiccup a bit watching the prop spray makes up for it plus meant to add if you don't run a pressure line all is good except violent aerobatics where you get the same hiccup for a split second.

FlyerInOKC

My Feedback: (6)

I would love to have the Little Red Book but I didn't think you would want to send it to the states. Saitos are the only 4 cycle engines I think are worth owning and flying! I'm spoiled with the best why fool with the rest?

Mike

Jim Branaum

My Feedback: (3)

Oh, for sure! On the correct airframe, flying in the rain is a blast. I was part of the out of town party that kick started an event we were visiting that was getting rained out. We taught them how to fly in the rain and had fun. The event has been that clubs only income generating effort of the year for over 30 years, even that year was successful.

Touch and goes in the heavy rain are simply awesome.

This particular airframe is scale and open cockpit so it does not qualify as being a wet baby.

spaceworm

Must be like the Porsches outrunning the Chaparrals at the Sebring 12 hr in 1966 or 1967 (CRS). The open cockpits of the Chaps filled up with water in the heavy rain and slowed them down. The closed Porsches then took charge. The wake and rooster tails of both were awesome. But the closed Daytona Coupe Cobras, beat them all at the end. (last Sebring I attended - then got married)