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dtr352
03-10-2005, 08:36 PM
I am trying to break in the cam on a motor I just rebuilt. The motor fires and revs to 3000rpm but after about a minute the number 5 exhaust pipe starts glowing red. What would cause this and how do I fix it?
MudPumper
03-10-2005, 08:40 PM
If you are running headers, they should all start glowing red near the block. Just be careful not to catch anything on fire.
MudPumper
03-10-2005, 08:41 PM
P.S. what kind of boat and motor??
dtr352
03-10-2005, 08:42 PM
I have my old bassett headers on it now. I thought I remember hearing that red pipes were bad but orange was ok. I don't know. So far it only gets red from the block to the bend.
dtr352
03-10-2005, 08:44 PM
southwind tunnel dragster, 460 bbc dual carb.
MudPumper
03-10-2005, 08:48 PM
I have my old bassett headers on it now. I thought I remember hearing that red pipes were bad but orange was ok. I don't know. So far it only gets red from the block to the bend.
Red is just a darker shade of orange, LOL. I wouldn't sweat it too much. One thing about doing it on a dyno is you can monitor EGT, air fuel mixture etc... to make sure your not hurting anything. Good luck, got any pics?
dtr352
03-10-2005, 08:52 PM
Pics are coming I just haven't had time to post them. I don't have a dyno so thats out. I am going to go pull the spark plug and make sure it isn't white.
MudPumper
03-10-2005, 08:58 PM
Fat is ok for now just make sure you arent runnin it lean.
dtr352
03-10-2005, 08:59 PM
#5 plug is definitaly alot whiter than the rest. Why would just one cylender go lean. How do you correct it. Any ideas.
victorfb
03-11-2005, 11:11 AM
you need to find out why that cylinder is burning lean. possible vacume leak, meaning air is coming in on that cylinder were its not supposed to. a cracked manifold on that runner will cause it. a leaking mateing surface on the intake manifold and head. also check valve adjustment. make sure the lifter is being pumped with oil. it may not be and not opening the valve enough for all the air and fuel. also and this one sucks is the cam lobe may have went south. this can happen in the first minute of break in. check to see if all the valves are opening the same amount. id be very careful as to finding out why that one cylinder is burning lean before i ran it again.