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Discussion Starter #5
Yup. Its all a learning experience. I'll do it all again but with some type of sensor.
Plugs were black on Thursday. I saw the fuel pressure drop below 5lbs. I got off the throttle but it was to late.
 

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Man I saw this on your build post and was hoping you were yanking our chain. Looks like some physical damage have to see the piston and valves and then it is hard to tell sometimes. Hope there is not too much colateral damage.
 

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Discussion Starter #10
The good news is the # 3 cylinder is OK. The Piston needs to be replaced and the head needs some filling.
So I'm going to upgrade to better exhaust valves. Have the head repaired and reseated. Recheck the springs and if needed replace them.

I already bumped the jets up 10 digits.

As I wrote before. I seen the fuel gauge drop and got off the throttle. As soon as I leveled off I heard a noise and shut down. After a few minutes I tried to start it and it wouldn't budge. I figure I seized the engine. So got a tow in from Billy (SKOM). Hopefully This is all I need to replace.

We tore the top end down today and found that the exhaust valve had broke off and was pinned between the head and the piston. From the looks of it the aluminum took a beating but gave to the valve but still taking out the plug.

I'll order the new piston & ring and call a local builder to see if he has time to re-seat the exhaust seat & weld up the head. Replace whatever needs to be replaced and be back on the water doing it all again.

I'll have a Pyrometer on before the next trip. I'm also going to upgrade the Fuel delivery. Any suggestions on a good fuel pump will be appreciated.

its all a learning experience. Hopefully it will be a better build when i get all the parts back.

I was real bummed last night. Hardly slept. But after getting the top end off. I'm much better now:)devil

Minor set back.
 

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The good news is the # 3 cylinder is OK. The Piston needs to be replaced and the head needs some filling.
So I'm going to upgrade to better exhaust valves. Have the head repaired and reseated. Recheck the springs and if needed replace them.

I already bumped the jets up 10 digits.

As I wrote before. I seen the fuel gauge drop and got off the throttle. As soon as I leveled off I heard a noise and shut down. After a few minutes I tried to start it and it wouldn't budge. I figure I seized the engine. So got a tow in from Billy (SKOM). Hopefully This is all I need to replace.

We tore the top end down today and found that the exhaust valve had broke off and was pinned between the head and the piston. From the looks of it the aluminum took a beating but gave to the valve but still taking out the plug.

I'll order the new piston & ring and call a local builder to see if he has time to re-seat the exhaust seat & weld up the head. Replace whatever needs to be replaced and be back on the water doing it all again.

I'll have a Pyrometer on before the next trip. I'm also going to upgrade the Fuel delivery. Any suggestions on a good fuel pump will be appreciated.

its all a learning experience. Hopefully it will be a better build when i get all the parts back.

I was real bummed last night. Hardly slept. But after getting the top end off. I'm much better now:)devil

Minor set back.
sorry for your set back, good to stay positive. I have had great luck w/ product engineering fuel systems. They were the only constant duty electric pump I could find when I was 1300hp 600ci motor. They offer a 2 year unconditional warranty. A little expensive, but great insurance.. Good Luck
 

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Discussion Starter #13
HAY CAVE
did the piston burn,.......or get beat by the valve?
Piston got beat by the broken exhaust valve. I was amazed to see that the cylinder was fine. It must have broke just as I was shutting down or the valve stayed flat. The spark plug took a good hit.

I'm not sure if I want the guys who rebuilt the heads to weld this sides damage up. I was told that they checked the springs and they were fine for my addition of a roots blower.

I have a bunch of people telling me to take the heads to a local shop. I'll stop by today and see what he'll charge me for welding up the damage, grinding to the correct cc, new exhaust valves and check the springs out again.

One piston and one ring set will be ordered today. If time allows, I'll go to Bergerons and see if they have a Pyrometer in stock. I may be able to tap the heahers myself but if not I'll let them do it.

Once I get the piston in we'll pull the engine and remove the rod and check the rod, crank and bearings out. I'm getting used to night shifts:D
 

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sorry for your set back, good to stay positive. I have had great luck w/ product engineering fuel systems. They were the only constant duty electric pump I could find when I was 1300hp 600ci motor. They offer a 2 year unconditional warranty. A little expensive, but great insurance.. Good Luck

Don't most larger pumps require a fuel return line to the tank?
 

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Piston got beat by the broken exhaust valve. I was amazed to see that the cylinder was fine. It must have broke just as I was shutting down or the valve stayed flat. The spark plug took a good hit.

I'm not sure if I want the guys who rebuilt the heads to weld this sides damage up. I was told that they checked the springs and they were fine for my addition of a roots blower.

I have a bunch of people telling me to take the heads to a local shop. I'll stop by today and see what he'll charge me for welding up the damage, grinding to the correct cc, new exhaust valves and check the springs out again.

One piston and one ring set will be ordered today. If time allows, I'll go to Bergerons and see if they have a Pyrometer in stock. I may be able to tap the heahers myself but if not I'll let them do it.

Once I get the piston in we'll pull the engine and remove the rod and check the rod, crank and bearings out. I'm getting used to night shifts:D
Hey cave, Looks like the valve dropping created the burned off electrodes? If the vale went away then were would all the heat go? it will burn the thinnest and weakest part in that cyclinder!!! Lets see the rest of the plugs:)devil
 

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Discussion Starter #20
Hey cave, Looks like the valve dropping created the burned off electrodes? If the vale went away then were would all the heat go? it will burn the thinnest and weakest part in that cyclinder!!! Lets see the rest of the plugs:)devil
OG,

Plugs 1 thru 4 look exactly or similar to the plug on the right.
Plugs 5 thru 8 look exactly or similar to the plug on the left



I should have replaced the exhaust valves with inconel from the get go. Live & Learn.

Jay of MHP Machine is replacing all the valves, Springs, 10° Locks, repairing the damage to the valve chamber, valve job and a new blower friendly cam with less duration. Previous Exhaust duration 316 @.575. Less reversion with the new cam.
 
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