Tinkerer

I hace LIGHTNING headers with silent choice.
I keep breaking the metal silent choice diverter plates.
this boat spits out two or three of these every year.

ANYONE ELSE HAVE THIS PROBLEM???

articfriends

iTrader: (1)

Tinkerer,how many hours are you getting between each time they break? I am also running lightning headers with silent choice and have never had same problem. I have run them for approx 200 hours,i did have a problem once with burning both actuater solenoids out,i mistakenly thought it would be a good idea to bend the lips on flapper slightly to keep water from puddling in y-pipe (even though they don't seal all that well) and when you ran boat over 5200 rpm's my circuit breaker i wired in would trip after 20 second's,i thought breaker was weak so i bypassed the breaker causing both solenoids to over heat and burn out. John at lightning headers was very helpful in figuring out what i did wrong,the water hitting the lip was pulling solenoids out of hold position causing the problem. I bent the original diverter plates straight,replaced the solenoids and haven't had problem since. I only run with them closed at 1200 rpm's or less and when i drive by the cops,are you running yours closed more than that? That might be why mine have lasted?

Tinkerer

I have almost dry exhaust and about 670 HP each.
they are lasting less than 75 hours.
I am just fatiguing them and they break in half and fall out.
I do run the silent mode higher up the RPM ramp then most do but I have an EGT and watch it for problems.
Non seen other than the plates breaking.

articfriends

iTrader: (1)

Just curious,are you dumping alot of water overboard somwhere else to make your exhaust almost dry?I want to cut back the water to my lightnings,i dump part of my water through a intercooler discharge then the rest goes out my exhaust.Has the linkage wore on your silent choice at all? When i replaced my solenoids i had to redrill the pivot screws bigger becausde the holes were elongated. The fatigue that keeps breaking your plates must be caused by the extra heat and pulseating caused by running them closed longer and almost dry. have you burned the hoses,are you still running the hose that came with them or something better?I considered welding up the water outlets in header and dumping some of my extra water overboard (was concerned about reversion) but i didn't need to with the cam i'm running. Maybe you could try a different material for your divertor flaps or have you already tried that? What kind of egt's do you run,i'm running gaffrigs with a probe bung welded in #7&#8 and they seem to read about 250 degrees hotter than actual temp(they run at 1450-1500 wot under boost but thats obviously high,the motor would have melted down long ago,thanks for any info you can give me,sorry none of this probablyt helps you with your dillema,Smitty

Tinkerer

I dump most of the water out on top of the drives.
Only the water that cools the engines goes out the exhaust.
Yes I do use the stock rubber exhaust hose and I do toast a piece now and then.
I am using the pneumatic actuators instead of the electric ones from Lightning.
There isn't any play in my linkage.
I think they are breaking just because the engines are preaty radical.
I don't hae to worry about reversion with the dry exhaust.
I have my thermocouples in the head at the exhaust flange. ( I know they should be in the header down stream from the flange about 3 inches.
I run mine at about 1350 - 1400 degrees and the plugs are a light tan with NO soot on the transom.