cozi500

Hi all i have a G3 running a c20let engine, just lately the oil pressure seems to drop, and the oil gets hot, i recently checked the oil cooler after it had run for an hr, the oil was reaching the cooler and the pipes are pressurised to it whilst running but the pipes are cold inlet and outlet from the cooler, also the oil cooler is cold oil in there, could the pressure relief valve have pack up and oil cant circulate properly? not sure the the oil temp at the filter housing and pump is hot, then from the inlet to the outlet of cooler is cold.? any help please

ChrisH

Sounds like you have a blocked oil cooler. Take the oil cooler off, fill it with water block one end of it up and try and poor it through to the other side, it shouldn't hesitate to come out the other end.

cozi500

Its got oil in there and i can blow through it with ease, the oil dosent seem to flow through it though, it seems to fill it up, but dont seem return to the engine, whats the best way of testing this, is there a flow and return from the oil cooler sandwich plate? it must flow one way,

ChrisH

Perhaps somethings blocked up in the sandwich plate or in the pipe somewhere.

cozi500

cleaned them out aswell, how does the system work, does the oil get sucked up the pick up pipe, via the pump, into the sandwich plate/filter goes round the cooler back the the sandwich plate, to a pressure relief valve, as the pressure builds up the valve opens returning the oil, yes. but what i cant understand if the engine oil is hot going through to the pump and to the filter, why isnt the oil cooler and pipes hot, surely the oil would cool down that quick, the oil in the cooler is nowhere near the temp as the engine oil.?

ChrisH

No, the pressure relief valve is purely if the oil pressure is to high, it will let the oil go through the system unfiltered. But everything else is right. That is very weird, so it's hot at the sandwich plate? I don't get it, theres pressurized oil in the pipes and cooler but it' not hot, if i said the pressure relief valve is busted then there wouldn't be oil in the cooler but would cause it to be cold....Very strange, i will have a ponder on it.

cozi500

Ive removed the pressure relief valve and spring, there was no pressure behind it from the spring though! i thought these had some pressure behind them from the springs.

ChrisH

It should consist of a spring and ball bearing, the ball bearing is what takes the pressure.

tabetha

Has the sandwich plate got a thermostat built in ?, as you don't know the oil temp if it isn't getting hot enough it WON'T flow, as it doesn't need cooling, normally they open at around 80-85C.
I've just fitted a state cooler to my 2wd sapphy and it stays at around 80C, so cooler is on off all the time cycling back and forth, maybe your oil isn't getting hot enough ?
tabetha

cozi500

No ball bearing, the let engine uses a spring and a plunger, the plunger takes the pressure.

cozi500

Yes themostat inside the sandwich plate, have got oil going through the cooler now, so thats sorted but have another issue.

cozi500

have another issue, when the engine is at temp on a run, when decelerating the engine will cut out and wont tick over, no fault codes though any ideas.