2tg oil pressure drop at operating temp

[2TG KE35]

at idle the oil pressure drops when operating temp is reached.

if you give it revs then the pressure increases at a steady rate.

it maybe a piston ring problem or some thing else.

the compression on all cylinders is a bit low under 165psi (should be 184.9psi according to river)

so I'm just wondering if this could be because of the rings or is this oil pump related??

your help would be much appreciated.

cheers

Preston

[-GT-]

That's normal, i see that on mine. As long as it isn't an excessive difference, you should see a slightly lower idle pressure when warm, compared to cold startup. This is due to the lower viscosity of the oil when its hot.

It comes up when you rev it so i'd say its fine. Does it seem too low? Does your guage have markings to indicate the pressure? Somebody may be able to tell you what pressure you should see.

[2TG KE35]

well according to rivers post on 2tg

the oil pressure at idle speed should be more than 1.1 psi.

i just went and checked it again and the pressure at idle is just above the 0 mark on the gauge. so not so good.

and also at 2000rpm the pressure is supposed to be between 40-60psi but my motor is at about the 20psi mark.

what could be causing the pressure to be low. the rings or the pump.

im guessing rings.

pce

[w810sc]

hey what type of gauge are you using, the TA22 GT oil/ammeter or an aftermarket?
if the GT sort, what type of oil pressure sender are you using, it could be the wrong one.
if you can get another oil pressure gauge install it and compare the differences (mechanical or electronic)

if you have the GT one, i read somwhere to use a VDO to correct the value of the sender.
http://www.toymods.net/forums/showth...light=pressure
i had this same problem.

fonzy

[Dale]

To answer your question the rings being shot wouldn't effect your oil pressure, it'd be the pump or a blocked gallery or something along those lines.

I think if your engine is still running then the issue will be with the gauge or the sender

[71TA22]

I think if your engine is still running then the issue will be with the gauge or the sender

Agree with Dale. Remember your oil pressure sender and guage if original will be 25+ years old.

I have been running a 2TG for 120,000km with the guage showing similar symptoms to yours. Oil pressure gets up to just over 60psi on a real cold start with choke. Once warmed up pressure is just above 0 at idle rising to just over 30psi at full throttle.

I have had the engine tested and oil pressure is in spec. Advise was that as the guage showed pressure all was well with the engine (if it showed no pressure then worry). Just keep a regular check on oil level.

If you are really concerned get the engine tested.

[rob20v]

This sounds pretty normal. I am curious as to what engine oil you use as I know some of the newer low viscosity oils will do this. If in doubt get your hands on a good oil pressure gauge (liquid feed) and temporarly replace the sender and actually check the pressure at the sourse. I do this on all engines I rebuild. At least then you will have piece of mind.

[goldta22]

Ive noticed some oils run lower pressure when warm than others but everything
sound all pretty norm to me you cant always expect the gauges in a 30 something year old car to still read the manufactures specs all the time stop stressing and just enjoy

[2TG KE35]

im using a brand new mech gauge.

you know those cheapys they have at the auto shops. its one of those.

the motor seems to run ok.

just needs the carbies tuned.

and before the gauge i was just using the oil pressure switch that i purchased new.

the pressure warning light never came on until she reached temp.

im using castrol gtx3 20w50 or some thing like that.

i got a quote on a new oil pump it was $275. BS

so a new oil or good condition oil pump with thicker oil??

what oils are you guys running in your 2tgs?

if anyone has a top condition oil pump they don't need im willing to take it off your hands.

cheers for all the help guys.

Preston

[oldcorollas]

can you get your hands on a direct mechanical gauge to test the pressure with?

a cheapy gauge could be plus or minus 10psi or more.. don't trust it for exact measurements.

is the oil still original colour? doesn't smell too much of petrol?
a 50 weight mineral should be fine, but you can try a 20W60 and see if it makes any difference..

i would still think it is the cheapy gauge.. which are usually just an indication of oil or not at higher revs....

can you borrow a VDO or a direct mechanical gauge?

[2TG KE35]

hey oldcorollas

well i can try to get a proper gauge when the funds are more plenty full.

but may wait a little while for that.

any suggestions on brands?? VDO u mentioned

ill have to check the oil smell tomorow.

as for the color its quite black in color, motor had oil changed not so long ago. hasnt been driven at all as its got not exhaust. but i have been running it. but only for short periods and it hasn't really revved past idle much. any particular brands of oils you would recommend.


pce

[2TG KE35]

the oil fukn smells of fuel!!

why would there be fuel in my oil?

[-GT-]

Incomplete combustion + blowby?

[2TG KE35]

to fix this i need to do what??

changed oil today pressure seems a lot better.

[rob20v]

You could check your compressions. The Toyota T series engine manual says the STD compression pressure is 165 psi with a minium pressure of 142 psi and a maximum difference between cylinders of 14 psi.
I tried to find the STD oil pressure but it is not listed.