Tom Jones

My Feedback: (4)

I have a saito 150s that I took the cylinder off to have a helicoil installed . while the head was off the rod came off the crank and I don't know which way it goes back on. I thought the chamfer on the rod faced the counterweight, but the engine will not start. Is there a way of telling by how the piston is orientated? Any help will be greatly appreciated. Thanks, Tom.

w8ye

My Feedback: (16)

Nope, the chamfer in the big end of the rod goes towards the counter weight. The piston is the same all around.

Tom Jones

My Feedback: (4)

Thank you. That's what I thought but wasn't sure. Cannot get the engine to fire. New plugs, using a starter so don't know what to do now. Again thanks for the quick response. Tom

ThumbSkull

My Feedback: (57)

Sounds like the cam is not aligned properly.

42etus

My Feedback: (2)

1. Did you take the cam cover off? If so, are you sure that the cam is timed correctly?
2. Do you have compression? If no, it will never run.
3. Make sure the pushrods are seated into the rocker arms correctly.

Yes, the chamfer goes toward the counterweight, but even if you had that wrong it would still run, just not for long.

More info. "It won't run" is pretty vague.

MetallicaJunkie

it's also a good idea to scribe an "x" on the so you can know what side is facing out, or also scrive and arrow on the piston so you put it in the same way

Tom Jones

My Feedback: (4)

Thumbskull, would removing the cylinder affect cam timing? I wouldn't think so. Tom

Tom Jones

My Feedback: (4)

42etus, the cam cover was never off, the pushrods are ok with a gap of .002, and the compression is fine. there is no pop when trying to start yet there is plenty of glow on the plug, which is new. Just don't know what to do to get it running. It ran before the helicoil insert was put in. Tom

SrTelemaster150

The con rod in my FA 150 has an "F" on the web of the beam. I assume that means "front"?

SrTelemaster150

Are you getting fuel? Put your finger over the muffler outlet if you have muffler pressure on the fuel tank, over the "V" stack if you don't. Open the throttle & turn it over W/O the glow igniter until you see fuel/bubbles moving into the spray bar (through the traslucent silicone fuel line) or it drips out of the carb. (don't over do it)

Connect the glow ignitor & have a go @ it.

My guess is that you are not getting fuel if the glow plug is lit.

Tom Jones

My Feedback: (4)

SRtelemaster150 I'm getting fuel dripping out of the carb. Thinking I might get a couple more of the "f" type plugs and see what happens. Tom

SrTelemaster150

I would think that even an improper plug that was otherwise functioning (glowing) would @ least pop & fire some.

Could your fuel be bad? Do you havean unopened jug of fuel to try?

Tom Jones

My Feedback: (4)

SRTelemaster150, Thanks for all the help. The fuel I have runs fine in a 46fx,but maybe I'll try a new jug. I'm using Cool Power 15% with 3 oz of castor added. Then again, I used a tank of a friends, don't know what it was but that didn't work either. Tom

SrTelemaster150

I used to run Byron 4-stroke fuel W/castor oil/synthetic blend in my 1st FA 150 many years ago.

I started noticing a metalic clicking/cracking sound as I turned the engine over when it was cold. The engine soon developed a problem W/a dependable idle & was sometimes hard to land due to the high idle speed required to prevent (engine) stalling. I tried running on board glow & eventually went to C&H EI to get a dependable low speed idle.

Eventually I found that the clicking/cracking noise was due to the exhaust valve popping from the seat due to gummed up castor oil making the valve stick to the seat. The muffler was acting like a megaphone, amplifying the sound. I switched to 15% Cool Power W/O ANY castor added & the clicking/cracking sound abated.

After a spectacular, straight in crash some months later, I dismantled the engine to clean the dirt out of it & replace the pushrods & covers. Upon inspection of the internal parts, I noticed that the exhaust lobe on the cam was severely worn. Horizon Hobby sent me a replacement cam & the idle problems were eliminated.

Was the exhaust lobe failure due to the castor oil gumming up the exhaust valve seat? Maybe, maybe not, but the fact remains that Saito recommends against using castor oil in the fuel. I stopped using it & my FA 150 had a gallon of 15% Cool Power run trough it every week for 2 saesons & it never gave me any more problems after switching to non- castor synthetic oil only 15% Cool Power.

Now, I'm not suggesting that castor oil is behind your present problem, but I would advise that you just use standard synthetic blend 15% Cool Power. There is no advantage to running castor in Saito 4-strokes & it can cause problems.

Tom Jones

My Feedback: (4)

SRTelemaster150, I'm not going to get into the castor or no castor debate, but I can't believe that castor would keep the engine from running. Tom

blw

My Feedback: (3)

There is evidence that castor protects the lobes.

Saito doesn't recommend against using castor.

SrTelemaster150

I never said it would.

Turk1

I would put some drops of fuel thru glow plug hole over piston then mount the plug and try to start it.I guess it would run for some seconds.Then it may triggers to continuous run also.

Tom Jones

My Feedback: (4)

Turk, will give that a try. Thanks Tom.

SrTelemaster150

Fuel just about has to be the issue.

The engine hasn't been torn down far enough to cause any issues as long as the valve lash has been adjusted.

Could be a prtially clogged spray bar in which case the above suggested "fiX" should yield some sort of results, even if temporary.

If it does fire but doesn't go into a "continuous run", remove both needles, give the spray bar a good flushing out & adjust the needles to factory setting to try another attempt @ starting.