bad oil pressure?

#1

i know that as the L series engines get old they develop a bad oil pressure problem. but unfortunatley my oil pressure gauge kept hittin zero when i idle and the engine is warm, does anybody know whats causing this problem and if the oil flows to the mains then to the camshaft or the camshaft down?

#2

'83 FSM, pg LC-9:

Oil pump
Pressure regulator
Oil filter
Cooler
then it splits
1) main brgs, crank brgs, conn rod brg, rod, piston squirter, pan

2) Cyl head -> chain tensioner
Cyl head, cam bracket, cam brg, cam, rocker, timing chain, pan

So, yeah, loose cam brgs could hurt pressure. So could a stuck pressure regulator (or oil filter bypass, which doesn't seem right to me, but that's the way it's drawn on the page).

Are you running an actual gauge? Oh, wait, yours is a gasser, which has a dash gauge. Wrong diagram. Start over. Pg. LC-2

[later]
L24e is pretty much the same as the LD28, except no oil cooler and the oil filter bypass doesn't dump to pan, but just . . . bypasses . . . the filter.

Might suspect the gauge system, OEM gauges are notoriously inaccurate. You don't need much oil pressure at idle, I'm happy with anything over 7 PSI. Just enough to turn off the idiot light.

Are L-engines known for low oil pressure when warm? What's the purported cause?

#3

usually the oil pump starts to puke around higher mileage L engines.

Im suspecting the gauge to be off because i opened up the fill cap while running the engine and i saw a good amount of oil coming out of the cam bearings. ill try to yank a oil pressure sender at the local pull-a-part and see if thats the problem im having

#4

Replacement oil pumps are very cheap for the L24e/LD28 engines, if that's all that goes wrong.

For testing, I really like a mechanical gauge.

#5

the sender is at fault, i ran a mech pressure probe and it was reading great. guess its just time to get a new sender

#6

Whew, NAPA wants $96 for the Echlin OP6081 for the LD28 or L24e w/analog guages.

Whereas the sender for the digital dash is Echlin OP6178 and is only $83.

They list a couple of Beck-Arnley senders too:

That one's only $30.

#7

And, if you've got the two-terminal unit (that NAPA implies is for the digital dash), there's one on eBay, ends tomorrow.

Auction 8033607466.

#8

naw i only got the single sender one, im planning on special ordering a new one the next time i get down to the local napa

#9

kassim503 wrote:the sender is at fault, i ran a mech pressure probe and it was reading great. guess its just time to get a new sender

What sort of numbers did you get for pressure? You have the gas motor don't you?

#10

yep ive got a gas motor,

when it was cold it ran at 50psi at 3000 rpm and idle was around 40

when it was warm (oil temp is 140 degrees) it was 45psi at 3000 and idle was around 20

when it was hot (oil temp was 200 degrees) 30 at 3000 and idle was at 10

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bad oil pressure?

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