robiebrog

My Feedback: (1)

Mike how did you have to cut the cowl for the muffler? Is that the stock engine mount. Is there enough back pressure for fuel feed on the BCM muffler -no pump or reglator needed? I plan to be at the D.O.G.S.'s show on Saturday. Will you have this plane there? I would like to see it as I am sure many more folks would as well. Does it make the lateral balance a problem, I don't want to run a 2 stroke inverted. I just don't want a YS and all the expense that goes with it's use. Thank for posting the pictures on your web sight.

AFSalmon

My Feedback: (3)

Did not have to cut the cowl at all except for a little on the bottom for the exhaust outlets. I made a cutout for the glow plug and a small hole to put a screwdriver in for carb adjustments. I took a dremel tool with a cutoff wheel and made a slot on the top of the needle valve - works great. I do have a serious problem though and that is the Bisson muffler I'm using does not seem to work well at all with the OS 160. It has to be a combination of the volume and backpressure but the engine quits in the air very frequently. I have switched engines with the 160 on my giant profile, which runs flawlessly, and same results. I've run the new engine on the profile with the header and pipe and it runs fine. I've redone the complete tank system three times. It's really got me upset as I can't fly the plane without the risk of the engine quitting. I plan to talk to Bisson about this. Also I know it's not just me because one other person I've talked to on the phone has the EXACT same problem I have with the Bisson muffler. He even tried the Cline regulator and it did not fix the complete problem.

I have no balance problems at all, mount the engine sideways like every other 2-stroke. The lateral balance is not an issue. We will obviously be at the DOGS and I'll have it in my trailer with me.

robiebrog

My Feedback: (1)

Thank you for replying so quickly. Tower has a sale going on and I was waiting for your experience before I ordered the engine and muffler. I wonder if the Slim Line one would be better or if the big round jett muffler would fit in the cowl. The Jett might have more back pressure. Otherwise maybe mounting the engine tilted 45 down and going with the stock muffler or a pipe. I just dont Know if they would clear the bottom of the fuse. I guess I will just order the engine and get a muffler later. I had considered a Moki 135 as well but it is a little taller and might require a hole cut out at the head as it might touch the cowl. the moki is 3.98" centerline to top.

STLPilot

My Feedback: (21)

Trailer ?? What a kidder.... Just look for a guy about my height torkin it down low. He'll be wearing an OMP hat too.

robiebrog

My Feedback: (1)

I talked to Jett engineering. They have run the turbo jett in cowl muffler a lot on the OS160. He said the 160 really likes the muffler. I told him what we are trying to do. He was not familiar with the yak but did say the jett muffler would have more back pressure. He also thought that if there is not enough cooling air flowing through the cowling with the bission and especially with the jett muffler that it would cause the problem's you are having due to heat build up. He had run into this problem before. The problem is you need twice the exit air as inlet to cool I believe.

AFSalmon

My Feedback: (3)

Yeah, look for the flamejob Hybrid torquing, I'll be flying that.

The OS 160 is a rockin' engine and I highly recommend it. It's all about finding the right muffler though. Love to hear others experience with different mufflers. I thought about the invereted 45 degree option, I actually did that on another sport plane years ago and used the stock muffler just fine. Saved me bucks from buying an aftermarket Pitts style. Plus it was designed to work with the engine properly.

basmntdweller

My Feedback: (9)

Since you said you would like to hear others experiences with the 160, I'll chime in. I had one in a GP Giles ARF. The engine ran flawlessly after I sorted out the low idle. I was setting the low needle same as every other engine I had owned. This was quie a bit too lean. Many had troubles with the Bisson muffler and several had plugged one outlet and solved their engine troubles. Others still had trouble. I didn't understand why so many had so much trouble with what I thought was the best running engine I had ever owned. Late last fall my Giles met it's demise due to stupidity on my part. I bought one of the GSP Katanas ARFs. I set it up exactly the same as my Giles with one small exception. On the Katana, I could not make this engine run worth a damn. Same prop, fuel, plug etc. I tried a Perry pump, no help. I swapped out the tank and lines, still no help. Finally I sat down with some pics I had taken of the front end of my Giles to see if there were any differences in setups. One minor detail, due to clearance problem, I had mounted the main needle valve on the firewall of the Giles. I had plenty of room on the Katana so I put it back on the backplate like stock. I figured that couldn make any difference but it was worth a try. I rigged it up on the motor box and took it out for a test. I left the cowl off cause I didn't want to cut another hole if it didn't help. With the cowl off, the engine ran beautifully as it always had on the Giles. With the needle set, I put the cowl back on and tried again. It continued to run perfectly. I have since remounted it properly on the motor box and cut a hole for it in the cowl. It has continued to run great. I no longer have one tube of the muffler plugger nor is the pump still on it.
I think I have heard of similar issues with some of the other backplate mounted needles. I have also had best luck with the OS "F" plug as the carb is extremely rich in the mid range. All of these fixes I heard about have helped some of the people, maybe one or all may help yours.
Matt

AFSalmon

My Feedback: (3)

Wow Matt, that is great advice. It's good to hear others have had similar problems. I'll try that needle valve trick. It must be a combination of things though as the OS 160s we run on the giant profiles run pretty much flawlessly and the needle valve is on the engine backplate. Those have headers adn piped running on those though. Must be black majic!

basmntdweller

My Feedback: (9)

One other factor in the equation, Prop selection, It seems that a larger oercentage of people having the problem run an APC 18-6. I'm guessing the heavy prop resists the firing of the cylinder more which transmits greater vibration into the engine/airframe. It's all speculation though. It could be we just weren't holding our mouth right
Matt

robiebrog

My Feedback: (1)

I think we are also dealing with a Heat problem. The engine runs fine on a profile(no cowl) but runs bad in a cowl. I am trying to figure out the best way to cut out the front of this cowl to get the heat away from the engine and muffler. Yet not trap it in the cowl. It seems that trapped heat in the cowl will be a problem. 4cyl's don't mind the heat as much as the 2cyl I guess.

AFSalmon

My Feedback: (3)

Hmm, the heat thing may be a factor but I don't think it's the main one. I tried several times without the cowling and no difference.

robiebrog

My Feedback: (1)

Have you solved the problem yet? I saw a Great planes extra 160 review where one of the bission exaust tubes was crimped on a OS 160 and this solved the problem. I have the engine now and will try a Jett in cowl muffler. It will probably be a while before I get to try this.

xtraflyr

My Feedback: (11)

Hey guys,


I had a 160 in my DP Extra with a bisson muff. and the needle mounted on the engine. Never had a problem running it. Had the bottom cut out so just the pipes hung out. I run an OS#8 plug and run it on 15%nitro 18%oil and I use a APC 18x6w. My dad now uses it in his WM Zero same setup and its fine. never a problem. Another friend has one in his H9 Cap and samething no problems.
I just put money down on Quique YAK54 and going to use the same 160.Getting it for a great price from my LHS $375!! So I hope I still have no problems..
Take it easy
Frank

AFSalmon

My Feedback: (3)

Major break through this past weekend! We tried several configurations with the muffler and crimped ends to provide more backpressure and then bam, my buddy noticed the vent line was full of oil. Guess what, the nipple on the bisson muffler is on the bottom and thus is getting clogged with exhaust oil creating a sink trap effect. So we plugged that hole and tapped a new hole right on the exaust flange for a new bleed nipple. Hooked it all up and it worked awesome. No more flameouts with the cowling removed. However putting the cowling back on led to one flameout half way through the flight. I think robiebrog is right in that there is also a cooling issue that needs addressed. Also probably need a little fine tuning with the cowling on also.