Series 3 Oil bath filter replaced with paper filter - breather hose hanging loose...

Hi everyone, as the title suggests I've just disconnected the oil bath filter on my 2.25 petrol and replaced it with a paper one that clamps straight on top of the carb (Zenith). I'm quite pleased as it was simple, looks quite nice, and more importantly the engine seems to start and run a lot nicer since the exchange.

The slight hitch is the little three-way hose that went between the elbow on the big air intake pipe, the breather cap on top of the engine, and the base of the carb. Obviously the intake pipe has gone so one of the hose ends is now hanging loose and I'm just wondering what best to do with it. I've blocked it temporarily to stop stuff getting in there and to be honest it runs fine like that, but I guess that's not ideal?! I was thinking maybe cut a bit of foam or something to pack in there as a filter and just leave it as it is? Any ideas?

Much appreciated, cheers.

By doing that you have disconnected the crankcase breather system which circulates into the carb. By sticking on the air filter it doesn't have the back pressure from the oil system or the crankcase breather. It may sound smooth but I suspect you'll see power losses / poor acceleration etc. Have you driven it?

John S said:

By doing that you have disconnected the crankcase breather system which circulates into the carb. By sticking on the air filter it doesn't have the back pressure from the oil system or the crankcase breather. It may sound smooth but I suspect you'll see power losses / poor acceleration etc. Have you driven it?

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Right ok no I haven't driven it yet so you may be right there. Is there anything I can do about that in your view? To be fair it also ran fine when I blocked the breather with my finger so I couldn't really work out how important it was...

My experience with this is actually with an MGBGT. I had K&N air filter fitted. The engine did have loss of acceleration but the top end power was eventually OK. You'll maybe not notice the difference with a series engine and the weight of the landy. At worst a slight retune of the carb could be required.

OK thanks well I'll give it a try as it is and see what happens. It's a Britpart paper filter so wasn't expensive at least! And I've still got the oil bath one so it can always go back on. Also mine's a lightweight so as you say hopefully it might only be a small difference in power. We shall see! Thanks for your advice. Booking the old girl in for an MOT today so fingers crossed!!

Is yours the T type system with one leg going to breather, one to carb and one to inlet. If so just get a small paper filter for the inlet end, it will suck dirt into the engine otherwise. Don't be tempted to block the spare pipe as that will over (de)pressurise the block when you're on the overrun.

I've gone back and forth between the oilbath and various cone filters and have to say in terms of performance I'm no longer convinced that there's much difference. Just with the DTML carbs the pipe is pointing the wrong way!

I was never happy with the K & N filters on my MG. Given the modest performance of a series petrol engine the oil bath type is fine and that's what LR designed. I like the concept in that all you need to do is change the oil regularly. Easy servicing in the back of beyond.