Oil

[Number 6]

what would cause a lot of oil to accumulate in the air intake pipe directly below the air filter box???

This is on a KV6 2.0 ltr..


any suggestions would be gratefully recieved

[tantallon]

Originally Posted by Number 6

what would cause a lot of oil to accumulate in the air intake pipe directly below the air filter box???

This is on a KV6 2.0 ltr..


any suggestions would be gratefully recieved

Blocked crankcase breather
Check all pipework and filters

[Number 6]

Originally Posted by tantallon

Blocked crankcase breather
Check all pipework and filters

Well i have just had a look and it apears that the breather pipe that goes into the inlet from the engine via a "T" piece is completly knacked,it looks as though it has melted at some point,this is the one under the engine cover...

[SD1too]

Originally Posted by Number 6

what would cause a lot of oil to accumulate in the air intake pipe directly below the air filter box?

The cause is linked to the crankcase breather system John as tantallon suggests but it’s not a blockage, quite the opposite in fact.

Each cam cover contains a wire mesh filter on the suction outlet of the crankcase breather system leading to the plastic inlet manifold chamber. This filter is supposed to trap oil droplets from the vapour by condensation, thus allowing only gas to proceed into the engine for combustion. The filter doesn’t work and so oil is deposited in the intake system and runs down by gravity, collecting in the air cleaner outlet hose.

By comparing the 75’s system with that on my SD1, my theory is that the filter on the 75 doesn’t stand a chance of working due to the high temperature and humidity inside the cam covers. By contrast the SD1’s filter is external to the rocker cover where it is cooler. I get no oil deposits from the crankcase breather on this engine suggesting that it is the placement of the wire mesh filter which is the cause.

It’s been suggested that maintaining the oil level below the ‘max’ mark on the KV6 dipstick is a solution. I have tried this without success. I have also tried an experimental paper fuel filter in the breather tube which has reduced the problem but not eliminated it altogether. A catch tank seems to be the only answer.

Simon