RAYGIB

My Feedback: (32)

Apparently this engine I bought from a friend requires some sort of 'choking rod' that did not come with it. On HH website there are 681 parts listed for this engine, but no 'choke rod'. Does anyone know what this 'rod' looks like or how to 'choke' one of these engines?

pilotpete2

Modern 4 stroke engines don't come with chokes anymore.
If you're hand starting and need to prime the engine, just cover the exhaust outlet with a finger while flipping the prop. That is if you're using muffler pressure to the tank.
If you use a starter, choking is a guaranteed to flood the engine.

Pete

RAYGIB

My Feedback: (32)

Pete: The manual for this engine states, under "Choking the Engine", The proper way to choke the carburetor that comes with your FG-40 is: 1. Make sure ignition is off, 2 - Open the throttle 100%, 3 - Using the included choking tool (long metal rod with threaded end) and insert this into the middle of the throttle barrel where you access the low speed needle assembly, then screw this into place, 4 - Pull on the threaded rod. It will move about 2mm. While you are pulling on the rod, turn the engine over 6 times. This method actually moves the low speed needle out of the way to allow a greater amount of fuel into the engine during the choking process, 5 - Remove the threaded rod and continue with the start engine procedure. Its this item in step #3, the 'included choking tool' that's the problem - it didn't come with the engine (I bought it used), and there isn't one shown on the 681 parts on HH website. Even two HH Techs couldn't find it, although he said that Tool Set SAIG3936 contained something that looked it might work. So I ordered that and it isn't even close. So I'll try to your advice and place a finger over the exhaust and flip it a few times. Its just kind of frustrating to spend so much time trying to find a part that I consider essential, that comes with a new engine but that can't be found! Thanks for taking the time to respond, Pete Ray

Cyberwolf

My Feedback: (4)

That sounds like allot of work each time to start a cold engine. Myself the finger over the exhaust is much easier provided your doing exhaust to help pressure the tank. The best way would be to block off the intake for a couple of cranks , but that is probably not an option.

w8ye

My Feedback: (16)

All the tool (which is just a rod with threads on the end) does is pull out the throttle barrel. You can use a metric screw to do the same thing or just pullout on the throttle arm?

RAYGIB

My Feedback: (32)

The fuel tank is not pressurized and the engine is buried within the cowling of a H9 Beaver. THANK YOU FOR THE REPLY. Ray

If I could just buy the #@!*&% part the problem would probably be solved!!

RAYGIB

My Feedback: (32)

I've tried about every size screw I have to mate up with that thread in the throttle barrel - 3mm, 4mm, 6mm, 4-40, 6-32 - nothing fits. I can't pull out on the the throttle arm as the engine is buried within the cowling of a H9 Beaver. Would you happen to know the thread size? Thanks for your time in replying. Ray

Truckracer

My Feedback: (19)

If the engine is mounted inverted, can you install a piece of fuel tubing that aims toward the intake and inject a bit of prime through the tube for cold starting? Seems like this would be easier to do that that rod system.

w8ye

My Feedback: (16)

hook onto the throttle arm and pull out on it?

hyltaiwan

That is a M3.5 0.5pitch thread, you can buy the cylinder screw set for SAITO 91S.
Solder it with a rod, and you got what you want.
Cut it to leave only 5mm long or you might touch the low needle and change your setting.

Cyberwolf

My Feedback: (4)

From my experence Jim ( W8ye) Has forgotten more about Saito 4 stroke engine's than most claim to know. He is a very good source of information

RAYGIB

My Feedback: (32)

Truckracer - I could, and maybe will, so that. It is inverted. However, another reply indicated that the screw that fits is a 3.5mm. If I can find one of those, I'll solder it on a rod and use that. W8ye suggested a hook, and that would work too. I guess I can close this thread. Thanks everyone for the help!

RAYGIB

My Feedback: (32)

I think that'll work - I can close this thread now. Thanks for your replies

RAYGIB

My Feedback: (32)

Thanks for that size on the metric screw! I guess I can close this thread now....Thanks for all the replies! Ray

ForcesR

RAYGIB; I am late to responding to your post, better late than never and this may be of interest to others. The choke rod comes in a tool kit that was supplied with my purchase of a FG36. The tool kit is still available and is listed under the FG40 parts list as part number SAIG3696 and is currently listed for $12.99. See attached photo.

Roger

RAYGIB

My Feedback: (32)

Roger: Thanks for replying. I did order that kit, but didn't think the rod was the correct size thread. It now looks like it actually is, and my ranting that 'it didn't come close' is probably in error! It hasn't screwed into the engine because it was not perfectly aligned at 90 degrees - the structure around the engine would only allow a less than vertical approach to the engine. I'll cut some of that away so it will allow a proper orientation for the screw to get to the engine. That should do it! Ray

RAYGIB

My Feedback: (32)

Thank you for helping me out from the other side of the planet! I guess the 'choke rod' does come in a package of tools offered by Saito via Horizon Hobby. Apparently I was not aligning the screw at 90 degrees while trying to screw it in, after some of the structure is cut away allowing the proper angle the problem should be solved. Thanks again. Ray

Gordon W

I know that this is an old thread. I came across it whilst searching for up-to-date, ie 2016, advice from guys using the FG-40 (there isn't any that I could find).

I own and have been flying two FG-36's for about 5 years. My two are the early ones and apart from the burp on take-off, have given no cause for concern in any way. Instead of the choke rod thingy, I take a long thin zip-tie and fully zip it up on the throttle arm. Being flexible, it allows you some leeway in positioning the exit hole in the cowl for the tail of the zip-tie to poke through, and it's easy to grip the end between finger and thumb and pull the throttle barrel out sideways.

Post #3 is wrong BTW. You CLOSE the throttle 100% to choke it. Four or five rotations of the prop then sucks in the juice.

What I wanted to know about the FG-40 is whether it has significantly more power than the FG-36, and if there are any prop/rpm figures available in any RCU or other forum. Also, has the burp on take-off been cured with the FG-40?

Cheers

Gordon

marvair

Hi there gents,


I am the unhappy owner of a SAITO FG-40. For the past 4 years... I shelved it two years and dusted it off over the winter to fit it on Hangar 9 Spitfire "30cc". After finding the ignition lipo 2S have a weld broken (intermittent 8.4V to 4.2V) and find out that 95E dose not work very well... I fed it 98 gasoline and it work fine on ground but in flight it sounds like it misfires or the cooling is not sufficient and it stops in flight. I open-up cowl exit vent and reopened the front + baffled the cylinder. Well it still misfires and some time it stops...
Now i have fitted a new stock carburetor the same things are happening... I am down to point the ignition system (original from Saito). I do know that these engines have a tendency to play hard to get but dam this one is give me a run for my money...

I can not find a reference for ignition box for Saito FG-40. (they are probably ashamed or out of stock...)

How do you see this problem on FG-40. Have you encountered such inquiry? Would you give me some tips on how to trouble shoot.

The carburetor can not suck gas when trying to prime/chock when the fuel lines are empty on the first start of the day...




Regards


Marv