heywier427

S13 Redtop.

Im pretty sure I know what happened, and what caused it to happen, but looking for someone to say, yeah sounds about right.

What caused it to happen - Heavy abuse, and pcv delete, and vent to atmosphere.

At high rpm, I got the heart saddening sound of oil starvation/beginning of rod knock. I know this sound well...
Immediately shut it down and coasted to the grass. Did I do it in time, I say to myself??? Pop the hood and there is oil dripping off everything below the waterpump & down... Dipstick shows down maybe 1/2+ a quart down...wtf. No oil light... Start it up, scary sounds. Turn it off. Google. Lifter tick?

So what I think happened was the block pressurized cause of no pcv/scavenging, which pushed oil out of the front main seal (which had signs of seepage), which momentarily stopped the function of the oil pump, which caused the lifters to bleed down.

Does that make sense to anybody but a hopeful me?

Lot of threads saying you must manually bleed the lifters, but has anyone tried pressurizing the oil system? This is the procedure that I know of for priming LS lifters, which are notorious for sucking at life/needing priming for no reason.

Will try pressurizing on monday and see what happens. Its not really a rod knock noise. Its def. a head noise, and it def sounds like 10 empty lifters clanking away.

What say you?

ANDY black s13

the oil pump is crank driven,
so if the cranks spinning it won't suddenly stop making pressure because of a leak
the pcv delete and vent to atmos if done so it can vent
the crankcase will make zero pressure
lifters dont need bleeding unless they have been turned upside down and air has got in as the oil has drained,one way check valve can hold oil for years
my guess is the oil got hot and thin and from cornering G's it starved the pick up

heywier427

Thank you for the response.

My rebuttal would be, my oil cooler is huge and puts oil cap. to 5.75qts. I only use 20w50 syn. with a zinc additive (super thick sludge), and I was also going in a straight line on the hwy. Not to say the oil still cant get hot doing a pull up hill on a hot day.

There are so many threads talking about lifter tick & low oil as a cause, thats where my thinking is coming from.

Also that the loss of the oil pump seal, didnt actually stop the pumping but allowed for aeration of the oil.

I will pull the valve cover/drop the oil, and inspect.

Thanks again for the response.

Edit: oil pump is upgraded S14/new pick up seal. Oil pan is not dented in any way. I actually dented it downwards/out, and it has over 10" of ground clearance with a sway bar under it.

Also, front main seal only leaked for this occurrence. Put the missing oil back in, and no oil is "pouring out". But I only checked this quickly/looked for dumping oil, because of the noise.

ANDY black s13

I wrongly guessed it was a drift day or track/grip event,
you seem to have covered most things with the cooler/oil grade/sump mods etc
if the oil pressure warning light is working then the pump was still making some pressure or more than 15psi if using stock switch,
could have a cracked oil pump gear,instant lower pressure but just over 15psi

possible the oil gallery feed to the head is blocked by old gasket sealant or something similar and the lifters are starved of oil/bled down as running/you heard the noise

have to get rocker cover off as you mentioned and see what it reveals
fingers crossed it is a simple fix