Ok so I have a friend who has a built 455 olds. Had all measurements and machining done correct by a very good machine shop and paid for it dearly. At the lake for testing on start up oil psi is at about 50psi. Heats up and of course oil psi drops to about 25 psi and that's pretty good for an olds. When throttling up oil psi increases as it should to about 40 psi. Bearing clearances are set at 3.5 thousands and running 2050 oil. We'll after a good hit of the throttle for a short while maybe 15-20 seconds and off throttle it shuts off. When trying to restart it acts like it's seizing up and doesn't want to start and white smoke starts coming out of the breathers only when trying to crank. Now backing up the pump was starting to make a weird noise kinda like a grinding noise but not really. So it's making a noise that probably shouldn't be there. It won't start and so he was frustrated and he gets towed back to the beach and the day was over. He's thinking the engine locked up and it's that. The next day he decides to try and start it and it cranks just fine and actually starts with 50psi at idle. WTF!!! We decide to cut open the oil filter thinking it should surely have metal shavings in it if it was locking up and it's clean no shavings at all!!! The question is can your pump lock up making it seem your engine is locking up when it really isn't. When braking the engine in we ran 3 sessions of 30 min each and oil psi maintained at 45psi with the pump disconnected.


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Easiest way to know is disconnect the driveline and see if the pump spins or if the engine spins that will determine in which direction you need to inspect further .


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I understand that but what I'm asking is under heat will it start locking up?  It spins freely by it's self but does that mean it's good?


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Hydro lock?

What was it doing when it died?

If I had even a question of the pumps condition, it comes apart.

It's running Bassett wet headers. I can see it may be sacking water. How do I stop it from sucking  water

It's running Bassett wet headers. I can see it may be sacking water. How do I stop it from sucking  water

What do you have controlling the water now? It should have a valve operated by pressure or rpm.

There should not be one drop of water on the headers below 1,500 rpm.

GT

What do you have controlling the water now? It should have a valve operated by pressure or rpm.

There should not be one drop of water on the headers below 1,500 rpm.

GT

Yea that's OK for sure I know it's not coming out until 1800-2000. .0035 was heavily recommended by many sources and people because of it being a marine application. So that's what I went with. Anything else I prefer .0025.

One more thing comes mind. When I was on that 15-20 second blast I was trying to get the nitrous to engage and it wouldn't. Kinda dismissed it and was going to check out the wiring and fuses on it later before it quit and was locking up. What if I was getting strait fuel and no nitrous and when I let off it drowned the engine Hydro locking it with fuel. Could explain the white smoke a little.

  It would of just flooded the motor and it would of been black smoke.

Yea true. I'm gonna disconnect to engine from the pump and run it and see what it does. Hope for the best. Also can different cams cause water to suck in more easily?

Yep.

Lobe separation should be 110° or greater if running wet headers. Duration cone into play also, if extreme.

GT

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Here is my cam specs.

Ok did a 30 min run at 2,000 rpm. Oil psi was good good as well. Pump disconnected so ruled that out of the engine. Go to restart engine and it's doing the same thing. Feels like it's locking up. Oil psi is good!!  WTF!!!  Went to feel the starter and it was at 230 degrees. Engine is at 150 degrees. That doesn't seem right. Found out the starter wasn't disengaging like it should and was stuck on the flywheel spinning the whole time at what ever rpm I was running and getting hot. So when I was to restart the engine the starter was locking up and making the engine seem it was locking up. So making sure in the future  I will deff make sure it's shimmed correctly. New starter is on the way.

Sounds like a wiring problem.

Hmmmmm.

GT

Could be the flux compactor

Ok did a 30 min run at 2,000 rpm. Oil psi was good good as well. Pump disconnected so ruled that out of the engine. Go to restart engine and it's doing the same thing. Feels like it's locking up. Oil psi is good!!  WTF!!!  Went to feel the starter and it was at 230 degrees. Engine is at 150 degrees. That doesn't seem right. Found out the starter wasn't disengaging like it should and was stuck on the flywheel spinning the whole time at what ever rpm I was running and getting hot. So when I was to restart the engine the starter was locking up and making the engine seem it was locking up. So making sure in the future  I will deff make sure it's shimmed correctly. New starter is on the way.

my 460 ford did the same thing. Changed the starter and the boat runs all day.


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Could be the flux compactor

you got to start thinking fourth dimensionally.....