indysupra

iTrader: (3)

You had me at "a strippers chest".

fbc25el

I hope that was foging oil that shot out of the exaust on start up

Quick2500

My BBC did pretty much the same thing. Had a consistent knock that wasn't able to be pinned down to one cylinder. Torn it down and found a spun and beaten main bearing. Had billet caps fitted and the mains line bored to fix the damage, and obviously a new crank...

c_deezy

iTrader: (1)

Here is an example of a spun rod bearing and the piston slapping the head: https://www.youtube.com/watch?v=yx57...ature=youtu.be


End result: http://www.offshoreonly.com/forums/t...converter.html

mike tkach

iTrader: (3)

92nsx,please report your findings on this,a lot of members are watching.

turbofox54

Is the knock at engine speed? Or at half speed? That's how I ballpark a noise as being in the bottom end or top end. Valve train runs at 1/2 engine speed.

92nsx

I would say the knock "speed" is the same as deezy posted. I wish I would have recorded it when I was idling into the dock. I was just pissed that it happened and didnt think of taking out the cell phone
I do have a boar scope in my hand, going to peak inside the spark plug hole and or valves along with pull the oil filter tonight, if time permits.

I have 12 yards of fill to move and pack down for the boat shed before this next 3 days of rain comes in.

Two questions:
Is there a way to check if i have a bad lifter? Or just crank the motor little by little and check for up/down play in the push rod?

Also Im sure its a waste of typing, But in the passed I have just ran conventional 20w-50 in the engine. This year Im runing 20w50, or 25w50 syn blend marine majestic oil. with 1 quart of Lucas oil treatment.
A good fellow buddie has had good luck with it in his 500HP's so I figured i would use it also. What are the odds that the oil may have caused this? I have maybe 45 min of engine run time on this oil change....

Yes: ManOfWar's video was of first spring start up with the motor being fogged down.

c_deezy

iTrader: (1)

Good luck with the investigation. I tried the spark plug wire removal trick when I was troubleshooting my truck engine but I didn't notice any difference in tone/knock with the plug wire off.

In my limited experience a lifter tick is just that, a tick and they will usually pump back up with a little rpm even if it's ticking at idle. I used to have a vid of that as well but I think it got left on an old phone...

Budman II

iTrader: (1)

A buddy of mine had a ticking sound develop after he leaned on it going after a challenge from a local Fountain. It sounded just like a lifter ticking, and we tried various things with the valvetrain trying to solve it. We finally gave up and pulled the motor, and found that one of the con rod bearings had been hammered flat and was squished out of the rod where it was hitting up against a main journal, producing the sound. Surprisingly we didn't really hear a knock - just the ticking. The bearing looked like a penny after you put it on the rail of a train track.

airjunky

iTrader: (2)

Cant recall any rod bearing failures that passed the cyl drop test , sometimes letting them idle in gear with the drive in a tub of water and exhaust going through prop helps. If you have blown the head gasket prior on that 502 yank the freeze plugs out and extract the sand and sediment out before you start taking the engine apart.
if you have a boroscope you may be able to pull the distributor and look for a cooked rod or main cap down past the valley drains and cam.and a wiped cam lobe if your gen5