3.9v8 oil pump dash light

Hello all, this is my first thread so will keep it to the point, i have common oil problem. The oil light flickers on idol and get overheating issues. I got hold of a high flow gear set but the drive ends are wrong. I was thinking of swapping the gears onto the appropriate shafts. could this work? or is there a better way to increase oil pressure and hopefully sort the overheating. i have other issues but will keep researching and maybe post again.

thanks for all the advise in advance

sounds like 2 issues, are crank and cam bearings worn, increasing oil flow isnt the answer to those, does rad get hot all over are youi loosing coolant

thanks jamesmartin for the reply,

i have installed a new cam and done a top end build. i didnt look at the crank. the rad gets very hot. if i had to the get to the crank is it possible from bellow?

Is it possible you have a rover p6 front cover / oil pump? These had female end on distributer drive iirc

Think I would start with replacing the oil pressure relief valve and possibly the pressure switch at the same time - quick, cheap and easy. If that doesn't sort it then like Jamesmartin suggested maybe a bigger issue. If oil pressure is too low you will get a rattling top end as the cam followers won't pump up properly at idle, mine rattles sometimes if its been stood a while as the followers pressurise, but other than that top end should be quiet and smooth.

Are you sure the overheating and flickering oil light are related? Oil pressure when very hot will be less than "normal" or cold, what grade oil are you running? maybe a heavier oil would help. Cooling issues won't help for sure, remove the rad, check it over carefully, look for evidence of leaks then check the core is clear, if it is clogged carefully clean it - don't use a high pressure hose you'll probably damage the rad. Then flush and reverse flush the radiator, then do the same with the engine (remove the thermostat) you might consider checking the thermostat is working - easy to do with a pan of boiling water.

HTH

+ 1 on the pressure switch. Many times it's the problem and a new one is cheap as chips. Plus, it's easy to get to.

thanks for the replys, cooltide, classickev and west slope rover. i have an early non serp engine, i am still learning about v8's and land rovers so excuse my lack of experience. i have a female distributor and a male ended drive on the pump. i will remove the pressure regulator on the oil pump housing and possibly replace as i would rather have piece of mind. i am using 10w40 oil and after the new parts i fitted i need to change the oil anyways. i will update with pics of the change of parts.

i believe the oil and cooling issues are related, i have checked the rad core and refilled with correct spec coolant and everything is ok as far as i can tell. I have also changed the thermostat, next i need to check the temp sensor for the fans.

It is not a p6 front cover then.

The flickering oil light and overheating - did they start at the same time?
Once, I did an oil and filter change and after that I had no oil pressure. Investigation went as far as dropping the sump to check the pickup wasn't blocked, running flushing oil and all sorts. Couldn't get the oil pump to prime at all then a friend asked about the filter, said put the old one back on, so dived in the bin and fished it out - hey presto instant oil pressure. The point here is an iffy filter could be an issue.

Once I had the oil light come on, had been out laning and then caned it home. had to stop at some traffic lights, oil light flickered at idle. Next morning seemed O.K. but then in the evening when I drove home oil light came on and stayed on - that was a sticky pressure relief valve.

The only way to have any certainty about oil pressure is to check with a gauge. According to the workshop manual - remove the oil pressure switch, fit test gauge. Get engine to normal operating temperature and run up at 2400 rpm, oil pressure should be 1.76kg/cm2 (25psi) so don't be expecting big pressure. The manual says if there is no pressure, check for an air lock. If the pressure is low, overhaul the oil pump.

.thanks again for the input, the oil light and overheating did start at the same time. i have changed the thermostat and getting sporadic idle now. oil light flickering. i think the first course of action is to drop the oil and filter check the oil pressure relief valve and have a good look at the pump gears. as for the idle setting has anyone done a base idol set before? i am hoping all this work on the oil system should sort the oil light flickering. the oil light does flicker on idle at traffic lights. the coolant has been in for a few days and is going well but fear the temp sensor for the fan has failed or not working correctly. is there a better or more controllable temp sensor i can put into the circuit or a switch to get the fans going?

i do go laning and have done some 'semi' trialing with a mate and the engine bay was boiling and have had to stop to let it cool down on a few occasions.

Act products have info setting up all aspects of hotwire efi on their site. You need to pack oil pump gears with Vaseline to assist priming

bacon3000 said:

.thanks again for the input, the oil light and overheating did start at the same time. i have changed the thermostat and getting sporadic idle now. oil light flickering. i think the first course of action is to drop the oil and filter check the oil pressure relief valve and have a good look at the pump gears. as for the idle setting has anyone done a base idol set before? i am hoping all this work on the oil system should sort the oil light flickering. the oil light does flicker on idle at traffic lights. the coolant has been in for a few days and is going well but fear the temp sensor for the fan has failed or not working correctly. is there a better or more controllable temp sensor i can put into the circuit or a switch to get the fans going?

i do go laning and have done some 'semi' trialing with a mate and the engine bay was boiling and have had to stop to let it cool down on a few occasions.

Click to expand...

Hold up!
Do you mean you don't have a viscous fan and you are relying on the AC condenser fans? If so then that is why it is running hot, you can't rely on the AC fans to keep it cool, just don't do it. Either get a viscous on there or put on a suitable main electric cooling fan pronto. You absolutely can't chance unreliable cooling.

Base idle - easy. Do a search, pretty sure there are a few posts on that subject.

Do look at the pressure relief valve and pressure switch though.

Hello all, yes i am not running a viscous fan and after a quick search i now have one. my oil issue has turned into a rather larger problem so will end this thread with a full engine rebuild after dropping the oil to test the shells on the crank! found more problems there and bad wear all over. The oil pump relief valve i think was sticking and have replaced with a new relief valve and a new set of pump gears. After stripping the engine completely i have found more over heating and burnt oil inside and have started the long process of rebuild on a budget, so will be a while. thanks for all the advice as i have found out how not to do things and found advice on here a great help. Thanks again.