Spinning the Hub?

I bought a 99' Triton TR20 from a Soldier that was moving to Korea. The first time I took the boat out on the water I noticed that it wasn't running like a Merc 200EFI. I took it to some friends at the local Triton dealership and they said the motor was blown. I didn't have any compression in cylinders 5 & 6. Of course the Soldier was already gone to Korea, so I was on my own to get it rebuilt.

I got the engine back rebuilt and ran it through the 10 hours of break in period. For reference this is what I did. 1-2 hours - trim all the way down, double oiled, stayed under 3,500 rpm. 2-4 hours - stayed under 4,500 rpm, still d. oiled, varied rpm levels. 4-6 hours - varieid rpm levels between 3,000 and 5,000 not getting on it really hard. 6-10 hours - I'd get up to full throttle but I wouldn't stay there long. I ran the whole first 42 gallon tank through double oiled and everything seemed to be working fine. Engine sounded great, ran great, 6,000-6,400 rpm kept me around 65mph or so.

At full throttle running up the river the engine sort of went into neutral for about 1-2 seconds. During that short time period the rpm's went out of control. Mind you I was already at full throttle running the river during a HUGE bass tournament. Once the motor "over reved" it blew to pieces. Has anyone ever "spun the prop" before? Now I have a prop problem and a brand new engine that doesn't work. How do you say... "up a creek without a paddle!" Any help or suggestions would be helpful. Thank you all.

Did you get a warrenty with the rebuild. If you have to pay to get it rebuilt again buy a factory rebuilt block from Mercury. The prop spinning only happens to older style rubber pressed in hubs. Thats one reason Mercury doesn't make them anymore. All their hubs are Flo-torq design now.

If I read this right, 6400 rpm on a 200 EFI.may be a bit high.6K? yea iv'e done that , but not 6400.

After speaking to multiple dealership and talking to various mechanics these are some of the things I've done to see what's wrong with my motor.

1) Spun hub - I've put the boat in forward gear and tried to spin the prop by hand/feet and was unsuccessful. Test failed. I did not spin the hub according to "X" mechanic.

2) Blown Gear box - I drained the BRAND NEW lower unit oil into a tub and did not see any pieces of metal where I may have sheared the gears. I did however have some very fine, dust-like metal shavings on the end of the magnet style screw. I don't know that those fine particles mean anything, so I don't want to rule this test a fail.

3) Blown engine - I pulled all the spark plugs out and none of them showed any signs of damage or excessive wear. All of those were brand new also since the motor was just rebuilt 11 hours ago.

If anyone has any more tests I can do to trial and error what my problem is, feel free to contact me via this thread or call me anytime at 931-980-7728.

Thank you

post this in the Mercury forum and I'm sure someone will point you in the right direction. good luck!

Did you check to see if the shifter is working. If the linkage or the cable is out of adjustment it may keep the motor from turning over since they will not start in gear. Will the starter engage the fly wheel and turn the motor over. I don't think most people could turn a prop by hand even if the hub had spun.