Holden 304 oil pressure issues, & no oil at rockers after rebuild

[GRPAVL]

I have 2 problems but first a run down, car is a vl calais now running a holden 304 v8 (as per my sig).

I originally thought that I had a dodgy oil pump as it wouldnt presurise after being rebuilt. After repacking it numerous times with vaso the oil lamp finally went out ..... now it wont turn back on .... ever.

When I have the key turned to on the oil light on the dash doesnt turn on though i do get engine check etc etc. There is no way it can have pressure while its not running.

I spliced the wire that runs from the oil pressure switch to the dash light and with the key still on shorted the end to earth. the lamp come on so thats fine and working as expected. Next I checked the orange wire had 12v which it did, and the purple wire has 12v when the fuel pump was working which it did. So I know the wires are ok but the oil sender doesnt seem to work. Is this a common thing for the 304?

Thinking that I may have damaged the engine by running it with no oil I removed the oil sender and replaced it with the sender from my old rb30 vl engine (via and adapter to fit the block). Luckily I still had the old oil sender wire so I reconnected that up. When I turned the key to on the oil pressure gauge wiggled bit to low, when I cranked it, it started up and almost instantly the gauge was fluctuating depending on the revs i gave it.

At this stage I was pretty sure my oil pressure sender unit was pooped but I decided to whip a rocker cover off just to check there was oil around the rockers etc. To my horror it was a little slimy but I would have expected to see more oil than that. I then got the wife to crank it for a second and the oil pressure gauge was working but I had no oil coming out the lifters to soak the rocker rails.

HELP ... what could be wrong and how do i fix it ....

Q

 

[GRPAVL]

oh and ive found other posts on this site while searchign before asking and they say

A) to check the oil pressure relief spring and check it's free length etc to check its not stick .... how, what, eh ??

B) the 304 run low pressure and it can take a while to lube up after a clean or flush (and mine is a rebuild) but i dont want to leave it idling to long as its only running headers at present and I like my neighbours. how long is a while, 20 sec, 1 min, 5 minutes ?

C) the oil filter should be filled with oil first before fitting, then fill engine oil to apprently prevent an air lock in the hydraulic system (causing low oil pressure). I did this when i vaso'd the oil pump last time and the time before.

D) Ive also blown into the suction pipe and can hear the oil bubbling in the sump (and being a rebuild know the pickup is clean)

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Any help appreciated.

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[GRPAVL]

anyone have a step by step on how to check the releif spring

anyone know how to test the oil pressure switch

anyone have any ideas where to start for checking why my lifters and pusrods arent giving the rockers any oil.

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[delcowizzid]

Go get a $20 repco mechanical oil pressure gauge .have you run the cam in at 2000-2500 rpm for at least 20 minutes first start has to be run up instantly to above 2000 rpm.it takes a fair while for oil to come out the rockers and if you have yellaterra rockers you wont get heaps of oil.

Sent from my C8660 using Tapatalk 2

 

[Darren_L]

you probably won't see a lot of oil at the top end at idle rpm or when you wind the engine over.
chances are you may not even have an oil pressure problem. But with no exhaust system fitted, you are never going to be able to hear any engine rattles etc from lack of oil pressure. Might be worth getting the exhaust system done before you go any further. I wouldn't suggest running the engine for any time until you can confirm if it has oil flow, the initial few minutes of running in a new engine are crucial to the survival of the camshaft in particular.

If you can't get the info you need here, I'd strongly suggest visiting the AussieV8 forum for some advice. There are a few guys there who know just about everything there is to know about these engines and always willing to help out

 

[GRPAVL]

its not a new cam (factory one thats done 160kms), and without any sensor in the hole it pumps the oil out nice when you crank it.

might get the oil pressure tester (rather than the vl dash one) and have ordered a new oil switch (only 40 bucks), that should tell me pretty fast. a mate of mate also told me today that the 304 has piss all flow in the rocker area till above 2000rpm so that has made me a little more releived.

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[GRPAVL]

feeling a bit better now.

went and got the new sender, and fitted it up with a t section so i can run the vl gauge unit as well.



first time round put the ignition to on and blam on comes the oil light and pressure goes to 0 on the gauge.

crank the car. Both show no pressure for the first split second then the warning light goes out and the gauge starts wobbling (as they do) at about 2 on the vl dash. kill the car. the light comes on and the gauge reduces to 0 again.

as for the rockers, I have been advised by you guys here and by a local mechanic that because they run a low pressure system there wont be any oil up to until you go over 2000rpm and even then its not that much. will wait to get the exhaust on and try again.

Thanks for the advise.

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[delcowizzid]

2 on a vl gauge is probably 2 bar which is around 29-30 psi depending on how accurate it is