Duclos Six Cycle

Home Model Engine Machinist Forum

Help Support Home Model Engine Machinist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Gordon

Well-Known Member
HMEM Supporting Member
Joined
Jan 4, 2011
Messages
1,416
Reaction score
384
For those of you who have built the Duclos Six Cycle Oddball engine. After getting this engine machined I have been having a problem getting it to run. After quite a bit of playing around I discovered that the piston in the bottom dead center position allowed the rings to pass beyond the lubricator hole in the top of the cylinder The result is that on the bottom of the firing stroke it allows the compressed gas to exit through the oil hole and sprays oil back through the hole. On the intake stroke it allows air into the cylinder at about 15° before BDC which I think is changing the air fuel mix. I have gotten it to run with and without a plug in the lube hole but the firing is entirely different. It has a much stronger firing with the hole plugged.

I have checked all of the dimensions and since I had redrawn it in CAD I checked the assembly.

Did I miss something or is the a correct situation? I am using a square O Ring for a piston ring.

Gordon
 
For those of you who have built the Duclos Six Cycle Oddball engine. After getting this engine machined I have been having a problem getting it to run. After quite a bit of playing around I discovered that the piston in the bottom dead center position allowed the rings to pass beyond the lubricator hole in the top of the cylinder The result is that on the bottom of the firing stroke it allows the compressed gas to exit through the oil hole and sprays oil back through the hole. On the intake stroke it allows air into the cylinder at about 15° before BDC which I think is changing the air fuel mix. I have gotten it to run with and without a plug in the lube hole but the firing is entirely different. It has a much stronger firing with the hole plugged.

I have checked all of the dimensions and since I had redrawn it in CAD I checked the assembly.

Did I miss something or is the a correct situation? I am using a square O Ring for a piston ring.

Gordon
Geez Gordon, You didn't get a single reply 11 yeasr ago. Do yhou have plans for this? If not, do you know where a fella can get them?
 
Back
Top