Warbird40

My Feedback: (24)

I recently acquired a Dream 110 Pattern plane with a inverted YS 110 (or 120 not sure), "Supercharged" engine. The plane sat for close to 2 years. Do I need to do anything in particular before starting this engine or should I give it a go. I know YS engines have extra parts inside as compared to an OS or Saito and would like to know the proper way of starting it without damaging the internals. The engine spins freely and has good compression. The previous owner ran it dry after every flight. TIA

Best regards,
Ed

Propworn

My Feedback: (3)

This is what I would do if it were my YS that had been sitting for any extended period of time.

I know he ran it dry each time but any fuel left will be old fuel so if it were me I would replace all the tubing including what is inside the tank. However sometimes the tank can be a bear to remove in that case I would rinse the tank using the old lines then replace what I could.

Your fuel should be pure synthetic as the silicon parts in the regulator/pump do not like petroleum based lubricants or castor.

Before you start remove the glo plug it makes things easier to work on.

You have good compression when you roll it over so the valve train is working ok you don’t know how much lube or if the valve clearances are correct. You can assume everything is ok as it ran when it was put away. If you decide to check it you must be careful not to tear or damage the valve cover gasket as some of the YS engines use the space to compress the fuel charge for the intake. You can usually remove the cover without damaging the gasket by just loosening the two cap screws and tapping on the cover until it breaks free of the gasket. Now you can remove the cover and check the valve lash and lube. A bit of 20/20 fuel down the pushrod tubes and on the rockers and valves and that should be good until the natural lube path takes over.

I have my own way of setting the valve lash that others may not agree with so I will just say it’s worth while to make sure you have the valve lash adjusted to the specifications.

With the plug removed squirt a bit of fuel in the cylinder and down the open carb. Spin over by hand never with a starter and the engine should feel smooth as silk. If you leave a little fresh fuel in the tank you should see fuel work its way up the fuel line to the regulator then out the regulator/pump to the carb as you continue to roll the engine over. The regulator/pump are working correctly.

Check the glo plug and make sure it is bright when lit reinstall, fuel up and try starting it.

The bearings are either good or they are not, running the engine will tell you right away no bearing noise your good to go but if you hear noise then replace them before damage to the engine can occur.

Warbird40

My Feedback: (24)

Propworn, thank you for such detailed response to my question. I have new fuel lines, fuel filter, new tank with all new internals and a new OF four stroke plug. I will follow your advise and get to it this weekend. Thank you once again for your help and time, its appreciated.

Best regards,
Ed

airraptor

My Feedback: (66)

Let us know how it turned out.

kenh3497

Sometimes the regulator will get gummed up from old fuel. It might be worth the effort to remove it and give it a good cleaning. Do pay attention to how the regulator is positioned on the crankcase. IIRC the "lug" points forward. Of course there is no harm in running the engine first. If fuel drips out of the carb on shut down you need to clean the regulator.

Ken

gmeyers

I would put some Automatic transmission fluid (ATF) in the carb then turn it slowly a couple of turns then flip it . You can also take some fuel line and fill it with ATF and hook it up to the fuel line and let the engine suck it in when you turn the prop. The ATF will lubricate the moving parts and the diaphram. you can substitute after-run oil for the ATF if you want.

airraptor

My Feedback: (66)

Gmeyers do you have experience with YS engines? I wouldn't put ATF fluid in my engine at all.

gmeyers

Yes I own several (4) YS 45'S one YS 60 and a YS 53 and have been flying them since the early 80's - after reading about a pretty extensive test of different products to be used as After Run oil the best results as far as maintaining rust free internals, and in the case of YS engines keeping the diaphram soft and pliable ATF scored the highest in the tests. I think maybe the formula may have changed some over the years but the result as far as I can see are the same. Rust Free engines and I am still flying my engines with the same diaphrams (one exception due to losing one). I use Power Master 20/20 fuel. I have a lot of regard for the YS engines and I bought extra pistons, cylinders and bearings to use about 1990 but never needed them .

Warbird40

My Feedback: (24)

Well I so far I have done the following:
Removed valve cover
Checked valves
Squirted 20/20 down pushrods, cylinder and carb
Changed filter
Inspected all lines

This weekend I will attemp to start it....will post update.

Best regards
Ed

airraptor

My Feedback: (66)

make sure regulator is clean. sitting that long can gum up and take a awhile to work correctly. Once you have the engine running let it idle for a bit and then run it up very slowly you may have to open the needle up a lot at first to get fuel flowing again.

Warbird40

My Feedback: (24)

Thanks will do. 😊

Warbird40

My Feedback: (24)

I know this took me a while due to being slammed with work. Anyways, today the YS110AC came to life after being stored for 2+ years by previous owner. After 3 seconds on the starter, it started right up. Sounds awesome. Thank you all for the help and advise.

Best regards
Ed

Propworn

My Feedback: (3)

Good stuff enjoy the motor

Warbird40

My Feedback: (24)

Thanks

acdii

I've got a YS63 that was given to me. I had to degum everything, using denature alcohol, and got it all back together. I had to soak the regulator and eventually needed to open it up as there was a chunk of goo in it that would not come out. Now it allows fuel to flow to the carb. It is the external regulator that attaches to the pushrod tubes. Just to make sure I have it back correctly, the screw should be flush with the body on the reg, correct? It pumps fuel to the carb with a few flips of hte prop, so I know its working now, but is there anything I need to look at before the fire up? I just got a new muffler for it yesterday.

Warbird40

My Feedback: (24)

Acdii, yes that is what is recommended as a starting point.

Best regards,
Ed

acdii

OOOH Excellent. Hoping to fire it up this weekend.

gmeyers

Yes the screw also affects the low end idle but that is a good starting point . Just make sure the engine is well lubricated since the alcohol would have unlubricated every thing. a little in the pushrods at the upper end, the valve lifters, the crankcase, cylinder (via glow plug using fuel) . Flip the prop a couple of times to make sure everything moves freely and might be a good idea to check the lifter clearance/play with a gauge. Good Luck

acdii

Ok, I shot it full of engine fog when I got it all cleaned up, did not want to risk anything rusting. Also checked the clearance sine I had to remove the rockers in order to free up both valves, they were stuck open. The previous owner used a lot of castor. Bearings are nice and smooth too.

Warbird40

My Feedback: (24)

Good luck and let us know how it goes 👍

airraptor

My Feedback: (66)

For valve clearance I always set mine up at zero when the engine is cold. If the rocker arm can move side to side should be good. When the engine warms up, the clearance opens up.

gmeyers

I set mine per manufactures recommendation at .004 thousands of an inch. I use a feeler gauge I bought on line - but they might be available at autozone or one of the auto parts places. Autozone, O'Reillys may even loan you one, they aren't expensive if you decide to buy one. My .004 feeler gauge is stainless steel but still so thin you can almost read a newspaper through it. The manufacturer provides a range that is acceptable but I have always used .004 on all my 4 strokes seems right. I bought a Golden Knight 82a because the valve lifter clearance was not enough and it leaked compression. I got a great deal on it and once I found the issue and adjusted the valves it ran/runs great. .

Hobbsy

My Feedback: (102)

If you happen to also own a Saito the Saito feeler gauge is .0039" and it's all I use.

airraptor

My Feedback: (66)

Gmeyers what does the YS manual say for valve clearance? Where does it start? As the engine heats up the clearance opens up even more so you are running a very loose valve train. Run the clearance how you like your engine. Get your engine warm then set clearance to .004 then let it cool off and remeasure.