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Discussion Starter · #1 ·
Hey guys,

Just want to start off saying I've been reading these forums for years now and I can't say enough for the quality of people on here and the info thats provided.

Time has come that I finally need to ask a question myself and hopefully get pointed in the right direction.

First off I have a late 70s Kona hull with a mild Ford 460 and berkely jet.

I was cruising around the lake pulling the kids on the tube at 3/4 throttle and when one fell off I looped around to pick him up, as I slowed and threw the throttle stick into neutral the engine died, which isn't normal. I tried to restart it and the engine hard cranked as if the timing all of a sudden was too far advanced and the cyclinders were fighting against the starter motor. It did fire up after a few cranks and I took off once again. While jetting back to the dock at near full throttle I heard a loud BANG and looked down to see 0 oil pressure on my dash gauge and the mech gauge I have on the back of the block.

I ended up limping back to the dock and I know I should have shut it off but there was zero noise coming from the block besides that first bang. No valve clatter no rod knock nothing. i eneded up pulling the motor and checked the oil pump, oil pickup and pump drive shaft. everything is a ok and no metal in the motor. Anyone have any ideas?? I expected the pickup to have fallen off or the shaft to have been bent. Got everything reinstalled and sealed last night. Going to put a manual pressure gauge on and prime the pump with a drill to see what I get.

Any suggestions are greatly appreciated,
matt
 

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Discussion Starter · #3 ·
Nothing visually wrong with the timing chain from underneath, just hooked up a drill and a manual oil pres gauge and spun the pump... 0 pressure. Out of curiosity I pulled the oil filter off and spun the pump again and it puked oil just like it should. Im at a loss now, kinda strange. The motor was rebuilt top to bottom 2 seasons ago by a reputable shop in southern CA so i know its not old sludge plugging a port
 

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OK ford has a gasket for the oil pump and if the bolts come loose you will lose oil pressure or you have internal problems with the pump

Sent from my QTAQZ3 using Tapatalk
 

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Nothing visually wrong with the timing chain from underneath, just hooked up a drill and a manual oil pres gauge and spun the pump... 0 pressure. Out of curiosity I pulled the oil filter off and spun the pump again and it puked oil just like it should. Im at a loss now, kinda strange. The motor was rebuilt top to bottom 2 seasons ago by a reputable shop in southern CA so i know its not old sludge plugging a port
Are you sure it didn't jump time? check the chain sides for slop
 

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Your description is vague but some of your symptoms suggest the possibility that you popped a lifter from its lifter bore.
 

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Oil pump drive shaft, dist gear drive pin broke... just throwing ideas out. Something is preventing the oil pump from turning. Also would explain timing off hard to start issue.
 

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Your description is vague but some of your symptoms suggest the possibility that you popped a lifter from its lifter bore.
I agree, if the pump is pumping oil out the filter then it is working fine. I would pull the valve covers and have a look, then turn the motor over and make sure everything is going up and down as it should... might have broken the cam or lifter is out of the hole like LakesOnly stated and not letting oil get back to the sensor passage...
 

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Im with Rex, it could drag enough to move oil without the filter. But not enough to make pressure.

Be safe, schick
 

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Im with Rex, it could drag enough to move oil without the filter. But not enough to make pressure.

Be safe, schick
If the Distributor drive pin shears the gear wont turn = no spark... The shaft for the distributor turns the pump driving by the gear. Ford's use a hex drive for the oil pump shaft itself...
 

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Discussion Starter · #15 ·
Oil pump is good, drive shaft has no indication of any wear. After looking st schematics of oil flow and with the noise its sounding like a cam bearing spinning. The diagrams do show bearings 3 and 4 passing oil through and up to the head so I'd guess if I lost one then the other would still be pumping. It is what it is but a rebuild at the beginning of season wasnt in the plan :cry::cry:
 

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Oil pump is good, drive shaft has no indication of any wear. After looking st schematics of oil flow and with the noise its sounding like a cam bearing spinning.
These engines rarely spin a cam bearing and I've never known one to fail in a mild and good running engine (ie, you'd been pulling a tube around the lake all day), but anything's possible.

The diagrams do show bearings 3 and 4 passing oil through and up to the head so I'd guess if I lost one then the other would still be pumping.
The 460 oiling system does not send oil to the valve train via cam bearings, the oil path to the cam bearings ends at the cam bearings. Also, the top end receives its oil prior to those galleries that divert oil to the cam bearings.

Keep looking.
 

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spun a main/rod brng? not knocking but turned blocking oil passage? Shit man I'd tear it down and save what you got now, a loud bang is never good.
 

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