"Burnt" spark plugs
01-05-2011, 09:57 AM
#51
Registered
Join Date: Nov 2001
Location: Pennsylvania
Posts: 3,385
Likes: 0
Received 0 Likes
on
0 Posts
I think he said he was running aviation fuel in some percentage. We would need to know the cc of the heads to know if the domes were too much. I run -12cc pistons with blowers.
01-05-2011, 10:55 AM
#52
Registered
Thread Starter
I think I need flat top pistons as well. Sucks the engines were just assembled. THis is a lesson learned from appliying car engine know how to marine application, two different worlds. I can run aviation gas 50% or 100% since its $4 gal. but this is not practical in the marine world. Problem is I have 2 engines that will have to be torn down. Piston dome is -17cc
01-05-2011, 11:16 AM
#53
Registered
Join Date: Nov 2001
Location: Pennsylvania
Posts: 3,385
Likes: 0
Received 0 Likes
on
0 Posts
I think you can make them live as is, you will just need to tune appropriately. Richer 12afr, less timing 31-32 and make sure the cylinder heads stay cool as possible. Alum heads would also be a benefit if you do not already run them. What is the current comp ratio?
01-05-2011, 12:39 PM
#54
Registered
Those look like little domes for closed chamber heads. I believe those run with open chamber heads give you around 10.5:1 compression. With the right tune up you should be able to work with that with 93 octane.
Last edited by picklenjim; 01-05-2011 at 12:41 PM.
01-05-2011, 06:36 PM
#57
Registered
Thread Starter
on another note, i would like to thank all of you for your valuable opinions and insight. all of the information and commentaries have been helpfull and educational for the future. hopefully I can get this engine toghether, tuned right and running smooth.''
again, Thanks
again, Thanks
01-05-2011, 06:37 PM
#58
Registered
Thread Starter
01-05-2011, 11:03 PM
#59
Registered
Join Date: Nov 2002
Location: SOUTHERN CALIFORNIA
Posts: 708
Likes: 0
Received 0 Likes
on
0 Posts
check fuel pressure, low pressure and or volume can lean a motor which will get the combustion chamber so hot the valve seats will fall out.
I had a carb float stick which caused needle to stay closed, motor was then only recieving half the fuel from the other side of the carb. pop! my engine looked exactly the same
I had a carb float stick which caused needle to stay closed, motor was then only recieving half the fuel from the other side of the carb. pop! my engine looked exactly the same
Last edited by JJONES; 01-05-2011 at 11:07 PM.
