Crankcase Breather Smoke

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Wes
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Crankcase Breather Smoke

Post by Wes »

I've had my engine given the once over by my local classic car garage and my fears have been realised. The engine is tired/worn and on its way out. But the mechanic said the engine still pulls OK and everything else about the car & drive train was excellent. So for the miles, I do, and until funds allow, I'm looking at palliative care. The only real pressing issue is the smoke coming out of the breather and the fact that at a stop in traffic it come out from the engine bay and looks like theres a small fire under the bonnet. So how can i mediate (bodge) this smoke issue?

1. Would a Ø17mm breather filter work?
2. A pipe existing somewhere else?
3. A pipe that comes up and joins the rocker breather into the air filter?
4. Guessing a bung in the pipe end is a complete no-no?
5. Any other ideas?

Thanks
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mobylette
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Re: Crankcase Breather Smoke

Post by mobylette »

I used to drive the works Vauxhall Viva van with a badly worn engine. The mechanics had drilled a hole in the bonnet and put the breather through. It was like driving a small train! Perhaps this is not a solution for you though.
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Wes
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Re: Crankcase Breather Smoke

Post by Wes »

mobylette wrote: ↑Mon Oct 05, 2026 9:03 am I used to drive the works Vauxhall Viva van with a badly worn engine. The mechanics had drilled a hole in the bonnet and put the breather through. It was like driving a small train! Perhaps this is not a solution for you though.
hmmm maybe not :-)
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oliver90owner
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Re: Crankcase Breather Smoke

Post by oliver90owner »

It would seem the only means of removing the smoke from the atmosphere is to direct it into the induction manifold. Putting it to a position outside the air filter will very quickly block the filter with oily deposits, if it is a paper filter medium.

If the reason for the excessive crankcase compression is worn bores or rings, nothing else will happen - apart from just getting worse.

If the cause is broken rings/piston lands, the engine may soon require extra repairs or fail completely.

One slight improvement may be to retard the timing slightly if it is presently too far advanced.

Blocking the crankcase will only cause increased pressure and likely drive oil through the rear crankcase scroll , perhaps causing clutch failure due to oil contamination.

As I see it, the only likely approach would be to direct the excess crankcase pressure away from the area, to where it is not a nuisance to you - but would adversely affect other road users - in particular any pedestrians who may be breathing in the toxic pollution from your engine. Not a good solution.

One of the reasons why I now drive an electric car is to reduce pollution - particularly for other road users and pedestrians. Fossil-burning engines are bad enough emitting tail-pipe toxins, without extra pollution from engines in poor conditions. Get my point?
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Re: Crankcase Breather Smoke

Post by Wes »

oliver90owner wrote: ↑Mon Oct 05, 2026 11:09 am As I see it, the only likely approach would be to direct the excess crankcase pressure away from the area, to where it is not a nuisance to you - but would adversely affect other road users - in particular any pedestrians who may be breathing in the toxic pollution from your engine. Not a good solution.

One of the reasons why I now drive an electric car is to reduce pollution - particularly for other road users and pedestrians. Fossil-burning engines are bad enough emitting tail-pipe toxins, without extra pollution from engines in poor conditions. Get my point?
Wholeheartedly agree. Just buying myself some time.

As an engineer working in the field of renewable power/fuels, yes you've reduced the pollution at the exhaust pipe for UK road users but not from the life cycle. EVs are more polluting in the early phases due to energy-intensive mining and battery cell production, not to mention the plethora of forever chemicals/plastics involved. But you could argue you'd have those in a new ICE car too. The whole renewable space is a mine field when it comes to "green" claims! My fav was a proposal I worked on to manufacture Solar panels in Saudi Arabia. Trouble was Middle Eastern sand wasnt good enough quality for the glass so sand had to be shipped to the desert from China!
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Bill_qaz
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Re: Crankcase Breather Smoke

Post by Bill_qaz »

A breather catch can would be a good temp solution, removing t oil from the fumes and lessening the smoke.
Screenshot_20261005-120422_Samsung Browser.jpg
Screenshot_20261005-120422_Samsung Browser.jpg (18.05 KiB) Viewed 326 times
Regards Bill
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Re: Crankcase Breather Smoke

Post by Wes »

Bill_qaz wrote: ↑Mon Oct 05, 2026 12:08 pm A breather catch can would be a good temp solution, removing t oil from the fumes and lessening the smoke.Screenshot_20261005-120422_Samsung Browser.jpg
Ive just been looking at theses. seems a good solution.
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Re: Crankcase Breather Smoke

Post by 59Elva »

Wes,
So have you tried the Rislone High Mileage Ring Seal Smoke Repair that you posted about earlier? My experience is the oil additive approach is generally disappointing. STP seems to be a viscosity booster that has quieted minor ticking and maybe slightly improved oil consumption but certainly not at the level that the advertising claims. I used a Lucas fuel treatment in my old Kia that appeared to clean the injectors. It did nothing in my Weber equipped MGB.
Bill B. ‘59 Pickup USA
Wes
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Re: Crankcase Breather Smoke

Post by Wes »

59Elva wrote: ↑Mon Oct 05, 2026 1:34 pm Wes,
So have you tried the Rislone High Mileage Ring Seal Smoke Repair that you posted about earlier? My experience is the oil additive approach is generally disappointing. STP seems to be a viscosity booster that has quieted minor ticking and maybe slightly improved oil consumption but certainly not at the level that the advertising claims. I used a Lucas fuel treatment in my old Kia that appeared to clean the injectors. It did nothing in my Weber equipped MGB.
No i just saw this as i'm looking for ideas to keep my car going a bit longer so wondered if anyone had tried
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Re: Crankcase Breather Smoke

Post by Sleeper »

Wes

No 3 , just burn it off ( for now.... ) .

John
Wes
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Re: Crankcase Breather Smoke

Post by Wes »

Sleeper wrote: ↑Mon Oct 05, 2026 3:39 pm Wes

No 3 , just burn it off ( for now.... ) .

John
Thanks John. Ive bought a cheap catch can and some piping to the air cleaner so let see if this works
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les
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Re: Crankcase Breather Smoke

Post by les »

Wes wrote: ↑Mon Oct 05, 2026 11:31 am
oliver90owner wrote: ↑Mon Oct 05, 2026 11:09 am As I see it, the only likely approach would be to direct the excess crankcase pressure away from the area, to where it is not a nuisance to you - but would adversely affect other road users - in particular any pedestrians who may be breathing in the toxic pollution from your engine. Not a good solution.

One of the reasons why I now drive an electric car is to reduce pollution - particularly for other road users and pedestrians. Fossil-burning engines are bad enough emitting tail-pipe toxins, without extra pollution from engines in poor conditions. Get my point?
EVs are more polluting in the early phases due to energy-intensive mining and battery cell production, not to mention the plethora of forever chemicals/plastics involved.
Imagine the battery production needed when/if everyone buys electric. That’s another point to get !

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Re: Crankcase Breather Smoke

Post by 59Elva »

I don’t see a downside to trying the oil additive. Its a cheap bet that might payoff.
I read a story about traffic camera sabotage over there:

“Rees denied all charges, but the court heard that he had run Facebook groups that agitated against the rollout of the network of smart surveillance cameras enabling the Ultra-Low Emission Zone initiative of London Mayor Sadiq Khan. Under the now well established system, owners of cars with older engines — which the Mayor decries as being more polluting — have to pay a steep daily fee to drive in and around London.”

Are Minors being taxed out of London or elsewhere? It would be ironic as they are featured in so many of the British tv shows that we see over here. Probably more than any other make or model with the possible exception of the black London taxis. Weren’t the taxis diesel?
Does the MMOC have a publicity agent that promotes Minors in film and tv?
Bill B. ‘59 Pickup USA
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Re: Crankcase Breather Smoke

Post by Bill_qaz »

[/quote]
Imagine the battery production needed when/if everyone buys electric. That’s another point to get !
[/quote]

We don't have a national grid to support if we all went EV
Nor the real estate on forecourts for enough charging points, we can't all have home charging.
Not to mention pollution from increased tyre wear due to the extra weight of EV.

LONG LIVE ICE :tu1:
Regards Bill
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Re: Crankcase Breather Smoke

Post by svenedin »

I think this engine could be palliated by having an oil separator chimney type tappet chest breather fitted in place of the swan-neck type and plumbed in to a PCV valve on the correct manifold. This does require sourcing the parts needed which would not be quick. The right manifold is quite rare now. The oil separator would almost certainly need cleaning out and re-stuffing with stainless steel pot scourer. This is the system that my 1969 10ME engine Minor runs.

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
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Re: Crankcase Breather Smoke

Post by les »

Just watching a programme that mentions mining for ingredients to make batteries, the nickel has polluted the once pristine rivers and is interfering with the populations access to water. Perhaps not as clever as may first appear to praise electric so much.

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Re: Crankcase Breather Smoke

Post by Bill_qaz »

les wrote: ↑Mon Oct 05, 2026 9:24 pm Just watching a programme that mentions mining for ingredients to make batteries, the nickel has polluted the once pristine rivers and is interfering with the populations access to water. Perhaps not as clever as may first appear to praise electric so much.
:tu1: yes just watched and thats just one of many.
Regards Bill
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