Oil Squirting Mi16 Head

[Gentrix 2 1 Cars]

Dear all,

 

a member from our german forum "french-classics.de" asked me for your help.

 

He is running an alloyblock Mi16, which is heavily modified for german means. Throttlebodies and some sort of mappable ECU.

 

He also runs big cams and therefore closed the oil holes for the hydraulic lifters, because he now runs fixed tappets.

 

The problem though, is the oil vapour.

 

He connected the outlet from the rocker cover directly to the sump and got loads of pressure, so that the spark plugs where sitting in oil.

 

He now has an oil catch tank installed, but gets a good amount of oil squirting in the tank.

 

 

What would be the best setup for his catch tank?

Premise is, no Oil vapour should be routed to the throttlebodies again – so should not be sucked into the manifold and combustion chambers, but can be re-routed to go back to the sump.

 

Are there any other modifications one could think of to reduce the pressure in the head?

 

 

Thanks in advance for your answers.

 

 

Andi

[welshpug 1,662]

I believe a restrictor can be fitted into an oil gallery in the timing belt end of the head.

 

part number 5 in this image is a one way valve;

 

 

http://www.miamistu.co.uk/pug/GB/309F/0/02A60A.HTM

 

maybe fit an insert of some sort that restricts oil flow?

Edited June 30, 2010 by welshpug

[boldy205 75]

I dont have much experiance, but would a calch tank with a drain going back to the sump for the oil?

[Jrod 7]

Those valves maintain a residual oil pressure in the hydraulic tappet supply (0.4 bars)

[Gentrix 2 1 Cars]

Thanks for the answers so far.

 

 

I dont have much experiance, but would a calch tank with a drain going back to the sump for the oil?

 

^ , sorry?

 

 

Those valves maintain a residual oil pressure in the hydraulic tappet supply (0.4 bars)

 

But what does that ^ mean - regarding his problem? should he remove this/these valve/s?

 

What about the Oilcatchtank-arrangement?

 

Isn't there a possibility to keep the crankhousing under vacuum without sucking oilvapour in the manifold?

If the crankcase has vacuum it should be possible to return the oil to the sump, right?

 

 

andi

[B1ack_Mi16 67]

Can't really see that the lifter oil supply will have anything to do with the crankcase pressure.

 

Either the crank case ventilation is underdimensioned, or the piston rings are blown and hence engine breathing too much air through crank case.

[Gentrix 2 1 Cars]

Can't really see that the lifter oil supply will have anything to do with the crankcase pressure.

 

Either the crank case ventilation is underdimensioned, or the piston rings are blown and hence engine breathing too much air through crank case.

 

 

Actually, it is blowing too much through the rocker cover ventilation - and you can not feed the oil back to the sump, because it is pressurised due to not having the standard breathers any more.

 

The question is how to reduce the pressurising in the head and how to set up the catch tank routing most efficient.

 

 

Andi

[Gentrix 2 1 Cars]

^ Anyone? Please

[engine killer 6]

I experienced much less issue than yours but it was still quite an amount of vapour from the breather.

 

A slight modification from the current breathing system has been done.

 

From the diagram, the cap (#2) should be connected to the inlet via a hose (#7). Instead of connecting to the hose (#7), I have it connected to a breather filter which trap most of the oil from the vapour before venting out. I have also drilled a big hole on the top of the cap (#2) and glued another breather there.

 

I think the twin breather should slow the speed of the vapour hence traping more oil.

 

Hope this help.

 

Will post some pict later.

[Gentrix 2 1 Cars]

thanks - I'll pass that on

 

andi

[engine killer 6]

hope you guys won't find this twin breather silly or stupid