Oil circulation issue??? Please help.

[lewise30]

Gday all. I am new to this forum and was wondering if anyone can help me with an issue I have with my E30 323i.

I recently purchased another 1985 E30 but with the m20 engine in it (previous ride was a E30 318i). Im not really familiar with these engines. But when i bought it the previous owner said that it had a dodgy oil pressure sender which causes the dash oil indicator to stay on...but now im not so sure.

It has the normal noisy rockers but will be adjusting them soon. So ive pulled the valve cover off and noticed that everything under there is very dry with thick black like carbon over everything...which tells me i have a oil circulation problem . So i took the oil tract off and made sure it wasnt blocked. I left it off and turned the car over and oil was coming out but not at a rapid rate. Refitted the tract and turned it over a while and oil seemed to be coming out but not as much as i thought it would. Is this normal at all or is there something wrong with the oil pump???

I have done a little research on the lubrication system and i beleive it relies on vacuum pressure to circulate the oil effectively...is this true??? As the hose that connects to the top of the valve cover was split from one end to the other where it connects to a T piece...oh and the vacuum hose that is connected to that T piece to the top of the intake was totally blocked. And also noticed oil in the throttle body.....

Can anyone help me try and rectify this issue i have with this engine. I have tried to explain it as best as possible without confusing anyone.

Any help and info is much appreciated thank you.

[HairyScreech]

The vacuum is not really an issue, it sounds more like this engine has been run pretty hot for quite a while, thus turning the oil to carbon. Where does the temp needle sit on the gauge? Past halfway?
The only way an m20 becomes sludged up like that is poor quality oil, lack of changes and/or heat.

It sounds to me like the first thing you need to do is get some of that crap out of the system, I personally don't like engine flushes and would rather see some good quality diesel oil used as the detergents added to diesel spec oil will do the job a lot better.
Expect to keep an eye on the oil and change it pretty quickly as it will fill with crap in no time.
A new filter before the oil goes in an a new one when its dropped out is also a must, you don't want all that crap going through the oil bypass.
There are more radical ways to deal with this but I wouldn't advise them by proxy.

When you set the valve clearances make sure that it is not the injectors tapping rather than the rockers, pretty common.
Also it may be wise to leave them until the oil system is cleaned out, unless the clearances are huge then a slightly slack noisy tappet is a happy tappet.

Re the breather hose, certainly unblock that and fit a proper hose, its not the cause of the op light but will not help, it is probably why you have oil in the inlet tract.

[lewise30]

Thanks for the info it will help alot. Regarding its running temp I've only seen it about half. But the previous owner did mention that it does get a little hot on highway trips.

[HairyScreech]

I wouldn't be suprised to see it has a 4 pot 90 degree thermostat in it rather than the proper 6 cylinder one, that or a nasty old radiator.

[lewise30]

Ok I will take the thermostat out and have a look and check the radiator as well. Why would the coolant light be on, on the roof panel? Could it be a dodgy switch? This thing definitely needs some tender loving care lol.

[lewise30]

What are the procedures to clean out the oil system. Will the diesel dissolve the carbon off the rockers, cams etc? I have a feeling the oil pump is failing, so what pressure is normal.

Thanks again.

[lewise30]

What are the procedures to clean out the oil system. Will the diesel dissolve the carbon off the rockers, cams etc? I have a feeling the oil pump is failing, so what pressure is normal.

Thanks again.