doxilia

My Feedback: (3)

I thought I'd put this to the collective wisdom - YS and OS engine experts:

I'm wanting to overhaul two used 60 size engines I bought but I've run into a couple of snags.

The first is a YS 61 AR whose drive washer is locked onto the crankshaft probably due to frequent tightening and poor maintenance. I figure a good drive washer puller might solve the problem but I haven't found a good source for one. Anyone know which one to get and where I can pick one up? With the drive washer off, I'm assuming I'll be able to slide the crankshaft off the bearings and clean and replace parts. On that note, the pump system seems to be missing gaskets and diaphragm and, more seriously, the chrome has started to peel off the piston sleeve. Aside from YS service is there another good source for YS 61 parts?

The second is an OS 61 RF-P (Hanno) which after considerable effort (not all physical) I was able to partially disassemble. The head and BP screws were somewhat rusted and were frozen in. Worse, someone apparently applied red thread lock liberally which prevented the screws from loosening. I've managed to get the head off but the BP, with its integral pump, is still frozen in place. What's the best approach to loosen this without damaging the BP or the pump. Never having disassembled an RF-P or SF-P I'm not sure if the pump is integral to the BP or whether it can come off by loosening the assembly screws. In any case, I'll still have to find a way to get the BP off. I understand I'm not to touch the factory set adjustment screw blue lock tited by OS as this throws the pump functionality off. Also, would using wet sand paper lightly (what grit? 800 or higher?) be the right way to clean carbon deposits on the piston head? The sleeve appears to be fine so I don't see a need to touch it.

Finally, what's the approach and advantage to using anti-freeze (ethylene glycol I assume) in engine cleaning? Is there an issue in putting drive washers (silver anodized aluminum) in this solution? I'll make sure I do not put colored anodized aluminum heads in this bath if I understand correctly.

Any advice much appreciated. Thanks, David.

YS 61 AR first three shots, OS 61 RF-P next four shots.

I added a final picture of the YS sleeve showing the chrome peeling. Is there such a thing as replating a sleeve (cost wise) or does this essentially write the engine off (other than for some parts) if another one is unavailable? How would the engine run with such a sleeve?

Atlanta 60

My Feedback: (18)

You should be able to put the YS AR engine in the oven for a few minutes and get the drive washer off (250-300*f)...I've never had to use a puller...Sometimes a build up of "gook" will develop which can make it tough to remove the drive washer...The YS's drive washers are keyed and have no taper...Heating will usually soften any build up plus loosen the tolerance so it will come off...Use the same method for removing the bearings from the case (ie: heating the case in the oven)...

YS parts and service for gaskets, diaphragm and o-rings...You can (should) use another source for bearings such as R/C bearings or Boca...

Sadly your AR liner appears to be FUBAR (I have one too)...You should check with flywilly when the Hanno/YS AR liner order comes in to see if any are left...The "AR" piston/liners are not available from YS anymore...You can however use the standard YS LS piston/liner if necessary...

The Hanno BP should come off with a slight "twisting" motion...In the photo you have posted you have the BP screws out..Now you have to break the seal between the BP and gasket...A slight rotation of the BP will normally do that...(The remaining screws on the Hanno BP are the pump screws...Do Not Remove Them as your pump will come apart and possiabley not function correctly once that seal is broken)

doxilia

My Feedback: (3)

Hi Chuck,

I knew a word of wisdom would come.

Oven... of course! I guess I should start with say 3 minutes and give it a try? If still stiff, another couple? I can actually see the key holding the washer on and I know those keys can get lost fast! Actually, on my YS 61-R (not AR, different head and no rear bearing lube screw just below RHS of carb) which is new, the drive washer slides on and off extremely easily. However, the problem there is that it actually slides on too much, meaning that it bottoms out against the crankcase before it hits the front bearing. Is there a small ring that goes between the back of the drive washer and the bearing to keep the washer at the correct distance? If so, it's lost. (I got the two YS's together).

FUBAR sounds right! I was wondering on the status of the piston/liner order. I'll drop Will a line. Hopefully he got my order for the Hanno. But, when you say I can use the "YS LS" piston/liner, are you referring to the 61-R or to the ones used say in the helicopter engines like the ST? How big of a difference in performance is there actually between the R and AR?

Regarding the Hanno, the BP is pretty much welded with glue and gook. Twisting is not happening. I could try the oven trick, my only concern is the pump. I'm sure there is silicon in there which holds up to serious temperatures but you never know. Is that risky? I won't touch the pump screws.

Thanks, David.

Atlanta 60

My Feedback: (18)

3-5min in the oven ought to do it on your YS...I've left them in there 10min plus...I just normally try not to exceed 300*...It will come up to temp quickly...Be sure to have a Hot Glove handy to handle the engine (voice of experience )

Yeah I wouldn't personally feel comfortable putting the Hanno in the oven with the pump on it...Not sure it would hurt anything...But....I'm just not sure...

I wasn't gonna mention this because I don't like to do it...But I have been in a situation similar to yours before...I made a wedge out of plastic, picked a corner lug on the BP, placed the wedge in the engine/BP seem and tapped it with a hammar...Once I got one corner started it came apart...(I've actually one of those small Craftsman screwdrivers in the past too but it will ding the engine and backplate...So I switched to plastic)

It sounds like the fellow who had your Hanno may not have used the factory gasket?? The factory OS gasket is some sort of plastic material and normally makes dis-assembly really easy!! It's usually the YS engines with their paper gaskets that give me problems..he he

Yes...There should be a washer/spacer **behind** the drive washer on the YS's...You'll need to get one of those from YS Parts and Service...

Yes...Apparently the YS 61 R (Pattern Engine) liner will work in the AR...The YS guru at YS Parts and Service is the one who told me this...I was going to order one for my bad AR until Aurora 60 started the Hanno/YS order....I decided to wait on one of those instead...I'm not sure what the performance difference would be...He just told me "it would work"...

doxilia

My Feedback: (3)

Excellent,

I'll give these suggestions a try tomorrow evening and report back. A painters spatula might do the trick on the Hanno - good thinking.

anuthabubba

My Feedback: (102)

Other ideas:


I've tapped a backplate with a small brass hammer to rotate/loosen it before. Doesn't always work and can damage the screw holes. Have also used a large Crescent wrench to turn the bp like a nut. Careful with the corner holes again. Maybe using the sides of the bp (wrench perpendicular) instead of the corners to mate the wrench to will spare the screw holes? Heat gun to the case ahead of the bp?

Terry in LP

Roary m

My Feedback: (67)

I have used a Monokote heat gun to heat up the engine and modified a battery terminal puller to fit around the thrust washer.

Fxrs_tim

Ditto on the battery terminal puller for use on thrust washers. They're dirt cheap and work well. You can pick one up at any auto parts store.

I've found that NeverDull works great for polishing the carbon off of pistons and heads. Just make sure you clean the parts well after using the NeverDull, and then add a bit of lubricant before starting the engine.

Atlanta 60

My Feedback: (18)

Ahh..Lubricant!! Normally one of the first things I mention... [:@]

You may already be aware of this but just in case..

Be sure not to use any petroleum based products on either of these engines as it will wreak havoc on the silicone parts!! I'd recommend either Ultra Oil (available from pspec) or Mobile 1 full synthetic engine oil (5/40 or lowest viscosity available)

Ultra Oil:
http://www.pspec.com/details.asp?ProdID=40&category=7

airbusdrvr

Synthetic motor oil at Walmart is probably the cheaper of the two choices mentioned above.

Roguedog

I use a heat gun as well. It works most of the time.

As far as the Antifreeze method I use the Green Prestone. This loosens all the brown black gunk off pretty good. The heads tend to need longer and/or more scrubing. I soak the parts over night in the AF then use dawn dishwasing detergent to finish them up.

Consider this when using antifreeze.
1.don't use the crockpot or other bowl etc for food after the antifreeze has been in there.
2. The antifreeze boils off so use ventalation of some sort don't want to breath that stuff.
3. Disassemble all parts completely before placing in the antifreeze.
4. Antifreeze will suck moisture out of the air so don't use it as a heat method to free stuck parts. Any moisture trapped int the freeze will excellerate or cause corrosion. Had this happen to an engine with a stuck piston and stuck liner. The heat worked great at seperating the parts but the absorbed water etched the liner all around where the piston had been stuck in the liner.
5. I have not put any anodized parts in the AF bath as I too heard that the coating could come off.

I think rainedave or atlanta 60 metioned Wright's Copper creme. This stuff works great for polishing up the Aluminum. I use Brasso for the gunk that the AF method leaves behind.

flywilly

My Feedback: (121)

As you've discovered, getting the drive washer off was the EASY problem!! Getting the backplate pump off sounds like a PITA. You can't use any solvents as they will surely damage the silicon diaphragm in the pump and excessive heat can be equally damaging. Repeated heating and cooling using a monkote iron may help loosen the backplate. If all else fails, take a Dremel cut off wheel and grind a thin notch at one or more of the mounting bolt locations as close to the main casting as possible. You can then use your bearing puller or a screw driver to pry off the backplate. Use care if you go this route as you don't want to exert so much force that you damage the engine. Heating also helps when doing this. There is a ... last resort, but I'm not going there unless absolutely necessary[X(].
Good Luck,
Will B.

Roguedog

I got thinking more about the backplate issue and this has worked several times.

Get a square ended exacto blade and use it as a wedge between the case and the rear cover. I would aslo follow flywillys advice and heat the engine a little.

Place the shape square end as best you can in the crack after the engine is heated and tap on the end of the blade lighty until it seperates.

I've only seen this happen when paper gaskets are used or when the regular gasket was now lubed with oil before it was put together. I always lube these thin gaskets some type of oil so I can get them apart easier.

IMPORTANT!!!! Be careful not to cut the aluminum crankcase housing it you try this. A couple of taps and it usually comes right apart. If it does not it's possible he used to much thread locker on the rear housing screws and it bled between the case and rear housing. If that's the case the only way to get it apart is heat.
I would try 200 degrees first for about 5-7min. Increase 20 degrees try again.

I've been meaning to get a thermal sensor for when the engine is running. Need to get one.

Is there anyone who knows the operating temp of these engines? Should be able to at least get the engine that hot in an oven without damaging the pump, right?
Bryan


Plug up the pump nozzles and spray some WD-40 around the edge and let it sit for a while.

grotto2

My Feedback: (2)

I don't know why you guys are so afraid to touch the OS pump. I disassembled every one I had at one time or another.

OS used some kind of threadlock (I guess) in the pump that would turn into a goo and cause erratic runs and flameouts. We would take apart the pump in sequence, clean all of the parts and reassemble it. I saw Ivan Kristensen do this once between rounds at a contest.

This one's surely due for the same routine, so take those screws out, pull the pump and pop that case in the oven.

Fear not!

Atlanta 60

My Feedback: (18)

That is Mighty Nice to Hear!!!

My fear has been instilled by Bax and reading of some older posts...I'm relatively new to these engines and did not own them back in the day...

Due to my curious nature I'll admit I have dis-assembled an OS Pump just to have a look...I re-assembled the pump and ran the engine with no problems...

I've been reluctant to advise anyone else to do it because figured I got lucky or something...

Thanks for the information!! I Ain't Skeered no more...

doxilia

My Feedback: (3)

Wow!

Great bunch of info guys. I should be able to get to it tonight. Grotto, I'll listen to your wisdom, if the pump re-assembles nicely, I feel much more comfortable taking it off before working on the BP.

Does anyone have a picture of a "battery terminal puller"? I sort of get the idea but haven't used one before.

grotto2

My Feedback: (2)

doxilia-

Just be smart about the pump disassembly. Lay everything out in order on a clean sheet of paper and note the positions where everything went. I seem to recall a couple of springs in there, but I don't think they launch themselves across the room or anything weird like that.

What you don't want to do is toss the pump parts in a bag and come back a couple of weeks later hoping to reassemble it by memory.

flywilly

My Feedback: (121)

When you remove the back of the pump - diagram everything and take notes as you disassemble it (with more diagrams). What may seem obvious while taking it apart can become quite mystifying when you try to put it back together - especially if it is a few days later. I learned this the hard way many years ago when I took apart an OS Wankel. Fortunately, I had another one (assembled) to use as a reference!
I've never had to disassemble an OS pump - even with 1,000s of flights on them. I do filter everything!

UStik

doxilia

My Feedback: (3)

Some progress. I'll report back tomorrow with some more pics.

In an nutshell, the pump and BP came off the Hanno as well as its drive washer. The piston sleeve is however stuck despite lubricant down the sides in between sleeve and case. What to do here?

On the YS, drive washer came off but the flat washer behind it rotated wrt the key and is stuck. I'm not sure how to go about rotating it without damaging the key and/or front BB.

Thanks guys, David.

UStik

Just a shot in the dark: an ultrasonic cleaner. The sleeve/case problem may be corrosion (engineer's biggest enemy, we used to joke) of the different metals. Special penetrating oil and turning the sleeve (if it's not fixed) with a two-pin wrench (brute force) might help. Or take a rubber mallet, hold the case in one hand and gently hit flat on top of the sleeve to losen it (shatter the sticky residue).

Roguedog

Now that the pump is off. Heat Man. Give me some heat man.
If you have a heat gun, heat the the outside of the case only. Try not to apply heat on the liner. Use welding gloves if you have to. You want to expand the case as much as possible, but not the liner. After its good and hot use a piece of spar hard wood and pry up on the sleeve through the exhaust port. Don't use something metal to pry with.
If no heat gun heat it in the oven for 10 minutes at 200. Pull it out and pry it with the hardwood again thru the exhaust port.
If that doesn't work. Sacrafice a stainless steel bowl. Place the engine in the bowl. Fill it with motor oil. Bake at 300 for 20 minutes. hehe. No kidding. Pull it out of the oil, wipe if off, a little tapping with the hard wood onthe bottom of the liner through the rear of the case. Should come loose.

This has worked for me on a stuck parts before.
Bryan

UStik

Yes, presumably it's that simple! If the sleeve has a smaller thermal expansion than the case, there has to be a press fit at ambient temperature. After all there has still to be a tight fit at working temperature for heat transfer to the cooling fins. So you have to heat it above working temp to get it loose (or heat only the outer part, the case). Just remove all other parts before (meaning especially the bearings).

flywilly

My Feedback: (121)

If you can't get the sleeve out using the above methods then try some PB Blaster which is a very effective penetrating oil. Of course, you will need to remove all traces of it before assmbling the engine as it will destroy the silicon parts. You can heat the case using PB Blaster, but use a heat gun and NOT your oven. The stuff stinks, is volatile and will really irritate your wife (trust me on that one [X(]). You will still need to 'push' the sleeve out - I just use a popsicle stick in the exhaust port.
Good luck!

bob27s

My Feedback: (19)

All of the engine components can deal with being warmed up a bit .. they get warm during normal operation if you think about it .... just dont "cook" the engine.

You can safely take an assembled engine up to 120-150degF with just about everything attached - let it soak at the temperature for a while (20-30 min). O-rings, some plastic, silicone parts are just fine up there. It is usually enough to loosen up gunk and fuel residue, free parts like backplates, liner, crankshaft, and in some rare cases you can even get the bearings out.

In genereral, you do not want to take the crankcase up above 325degF for assembly/disassembly under any circumstances. Heating the case above 325 deg. F. can/will affect the heat treat of the crankcase material.

Use long term controlled heat, rather than high/directed/agressive/uncontrolled short term heat

Use an oven - no torch. Heat gun can be just as bad. They can reach localized temps exceeding 500 deg in a hurry.

Bearing changes usually require something more on the order of 300-325 degF soak for about 15-20 minutes.