Spark Plug Problem

[crispy critter]

I checked some earlier post to find the REM37BY is about the shortest plug that will thread into the head on an O200. I agree with Forrest thinking this plug is a little cold for this engine. I have one plug on the top of number 4 cylinder that is barely rubbing the "COWL BUMP". I have tried every thing to get enough clearence but it nut on the plug wire that threads onto the plug barely rubs the lower front inside of the bowl bump. If I could find a plug that is 1/16" shorter would be plenty to give me clearance. I'm also very open to any other ideas you might have. The only other solution I can think of is to replace the left side cowl door which I really don't want to do right now. Do you guys think the REM37BY will work ok in the O200 or even better ,is there a hotter plug that is just a weeeee-bit shorter then the REM40E's used in the O200....it really won't take much. It doesn't touch while on the ground,it doesn't touch during normal ground runs,but it does touch sometime during flight(don't ask how I know that yet). Remeber these are for a non-electric 0200 on a short mount.....most normal rules that work for the A65 are blown straight out the window with this one.

[Ragwing nut]

Re: Spark Plug Problem

I checked some earlier post to find the REM37BY is about the shortest plug that will thread into the head on an O200. I agree with Forrest thinking this plug is a little cold for this engine. I have one plug on the top of number 4 cylinder that is barely rubbing the "COWL BUMP". I have tried every thing to get enough clearence but it nut on the plug wire that threads onto the plug barely rubs the lower front inside of the bowl bump. If I could find a plug that is 1/16" shorter would be plenty to give me clearance. I'm also very open to any other ideas you might have. The only other solution I can think of is to replace the left side cowl door which I really don't want to do right now. Do you guys think the REM37BY will work ok in the O200 or even better ,is there a hotter plug that is just a weeeee-bit shorter then the REM40E's used in the O200....it really won't take much. It doesn't touch while on the ground,it doesn't touch during normal ground runs,but it does touch sometime during flight(don't ask how I know that yet). Remeber these are for a non-electric 0200 on a short mount.....most normal rules that work for the A65 are blown straight out the window with this one.

I am pretty sure the REM37BY won't clear the piston. The reason it is shorter is that the electrode is deeper in the cylinder chamber. What I did was get some Breeze spark plug shields and run M41N unshielded plugs which are approved in the O-200. You will have to change the nut at the spark plug end. It is slightly different than the one on a shielded plug.

Mike

[crispy critter]

Re: Spark Plug Problem

What is a Breeze spark plug shield and where can I get one...is that the same thing as the can that has to be made?

[jason packham]

Re: Spark Plug Problem

I have been running the rem37by short plugs for a year.Running on mogas and 100ll.No sign of any probelm.

[crispy critter]

Re: Spark Plug Problem

Jason,what engine are you running?

[flyguy]

Re: Spark Plug Problem

Kevin,
Don't know about the Breeze, but I am running cans ala Erocoupe. The ones I have don't work well with 41's because they get stuck in the counterbore at the bottom as the hex is very short. I understand from on here that Fresno airparts (not too far from here) has some kind of similar can for sale. I was going to check into it for myself and can see what they have and what it will work with if you want me to.
It is a pretty nice trip in the plane if our hurricane cross-winds here will just cool it for a while.
Darryl

[3Dreaming]

Re: Spark Plug Problem

In the clip wing I restored we are running the Autolite version of the 37BY's with Slick mags and harness. No problems with the running so far. I had 1 lead that was to close to the cowl. I took the end apart and shortened the small hex backing nut by about 1/8". Tom

[jason packham]

Re: Spark Plug Problem

The engine is a 0 200 with slick mags on short mount.My top plugs are unshieded ac 88.Going to change top plugs to D-16 champion to reduce radio noise.I hope?

[crispy critter]

Re: Spark Plug Problem

Thanks everyone. This has given me a lot of good ideas....I was really startingt o dread remaking a top cowl door with everything ready to fly.

[Ragwing nut]

Re: Spark Plug Problem

Why not just add the bumps? I didn't think a BY plug would clear the piston since the piston is notched on 85's to clear the spark plug bushing. The Breeze cover is a can that attaches under the spark plug to the cylinder. The true Breeze cover is tight at the base, but there is a cast one I have used.

Mike

[rotaxflyer]

Re: Spark Plug Problem

Jason,

I was thinking of going the tractor spark plug route as well. Any problems with them? 2.99 at TSC is a whole lot better then mail order for 30.00 a piece. Did you change your wires to fit the smaller connection?

Andy

The engine is a 0 200 with slick mags on short mount.My top plugs are unshieded ac 88.Going to change top plugs to D-16 champion to reduce radio noise.I hope?

[crispy critter]

Re: Spark Plug Problem

Why not just add the bumps? I didn't think a BY plug would clear the piston since the piston is notched on 85's to clear the spark plug bushing. The Breeze cover is a can that attaches under the spark plug to the cylinder. The true Breeze cover is tight at the base, but there is a cast one I have used.

Mike

Mike,
I am running an O200 not a C85. I have the cowl bumps but I also made one mistake when fitting my cowling. When I installed my engine to fit the cowling back sometime ago,I used a set of machined bushings to adapt the rubber cone mounts to fit the 0200(without the oil tank installed).When I started the final assembly the oil tank was hitting the engine mount so I decided to go back the original 0200 mount bushings. We had to redesign the baffles and a couple other things to make it work however I didn't think about the spark plugs when I decided to go back to the longer(3/4") mount bushings. Now the #4 plug wire is just barely touching the lower front edge of the cowl bump,only while under power. It won't take long before it will wear a hole in one,or both the cowl bump or the plug wire. All I need is 1/16" to have enough room to eliminate the problem...that's all. If I can't find a way to shorten the plug then I will have to remake the left side top cowl door! I could move my cowl bump forward but if I do then I will have at least 3 of the original cowl bump mounting holes exposed just behind where the cowl bump would be moved to and I don't want extra holes in a brand new cowl door for everyone to see and say,"what are those holes for?".

[Ragwing nut]

Re: Spark Plug Problem

Mike,
I am running an O200 not a C85. I have the cowl bumps but I also made one mistake when fitting my cowling. When I installed my engine to fit the cowling back sometime ago,I used a set of machined bushings to adapt the rubber cone mounts to fit the 0200(without the oil tank installed).When I started the final assembly the oil tank was hitting the engine mount so I decided to go back the original 0200 mount bushings. We had to redesign the baffles and a couple other things to make it work however I didn't think about the spark plugs when I decided to go back to the longer(3/4") mount bushings. Now the #4 plug wire is just barely touching the lower front edge of the cowl bump,only while under power. It won't take long before it will wear a hole in one,or both the cowl bump or the plug wire. All I need is 1/16" to have enough room to eliminate the problem...that's all. If I can't find a way to shorten the plug then I will have to remake the left side top cowl door! I could move my cowl bump forward but if I do then I will have at least 3 of the original cowl bump mounting holes exposed just behind where the cowl bump would be moved to and I don't want extra holes in a brand new cowl door for everyone to see and say,"what are those holes for?".

I knew you were running the O-200, but the piston TDC is very high in the cylinder and BY plugs or any other "tractor" plug isn't legal either. I probably have an extra shielded cup here you can have or use just so it is done legal and right considering you are getting ready to go through a conformity inpsection. I made and used a set of those bushings with no clearance problems. You running a long or short mount?

Mike

[crispy critter]

Re: Spark Plug Problem

Mike,
I'm running a short mount. How much do you want for the can?

[3Dreaming]

Re: Spark Plug Problem

I knew you were running the O-200, but the piston TDC is very high in the cylinder and BY plugs or any other "tractor" plug isn't legal either. I probably have an extra shielded cup here you can have or use just so it is done legal and right considering you are getting ready to go through a conformity inpsection. I made and used a set of those bushings with no clearance problems. You running a long or short mount?

Mike

The REM37BY plugs are approved for the small Continental engines.