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 Posted: 04-02-2020 04:08 pm
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Ralph H
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Hi All
I have looked at a bunch of threads on this topic but nothing recent with photos still available. I wonder if anybody can show or describe a setup to vent the Crankcase other than into the back of the stromburg pancake style (dome shape) air filter. I have read several places about using a K&N filter or others that talk of running a piece of hose down and under the car. Looking for best solution.
2. related to this How much volume and what sort of air/vapours/oil/stuff comes out of this vent.

As of now I have a smaller hose from the back of the carb loosely stuck 4 inches into a larger diameter hose clamped to the block. It is a loose fit now with a gap around the smaller hose. Should this be a closed system ie. not open to the open air.
Any help appreciated.
Ralph

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 Posted: 04-02-2020 05:11 pm
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redracer
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The standard way with the aftermarlket K&N filters, was to use a 1/2" hose on the back of each filter going to a "T" fitting, which in turn fits VERY snuggly into the vent hose on the back of the engine.
However, in a hard left turn(think autocrossing) if the oil level was up to normal height, one would get some oil up the breather tube which got sucked into the carbs giving plumes of smoke out your exhaust(looks like you had just blown your engine)
On the race cars, the preferred place was to drill a hole in the center SQUARE on the top of the large auxiliary oil pump housing. Why this wasn't done to begin with, I don't know, as the location is very high up with no possibility of oil getting sucked in, plus it is always open for crankcase breathing.
hope that helps, bruce

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 Posted: 04-02-2020 09:29 pm
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Ralph H
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Redracer- Ok so what your saying is this vent hose thingy is intimately connected to the oil in the block and can at times send quantities of oil out of the system and needs to be kept under control. Could explain why there was a bit of oil on the block around and under the carbs. I blamed that oil on the Distributor shaft oil seal and have replaced that this week also.

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 Posted: 04-02-2020 10:58 pm
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redracer
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When you say distributor shaft seal, I hope you're talking about the internal one below the centrifugal weights? This one is notorious for leaking and the very early Healeys didn't even have one!
The exterior "O" ring on the shaft is almost never a problem.

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 Posted: 04-03-2020 08:51 am
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discogodfather
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I used to run K&N oval filters on my Webers then moved to some custom velocity stacks to try and get some lower / midrange power (with something like 107's cams) back. They did in fact connect to the oil separator to the back of the plate on the K&N's and the rear carb was oily sometimes but it did not miss.

I lost any way to connect to carbs with the stacks, so rather than plug it I just put a miniature K&N filter on there. It does smell a bit and you can see some fumes from time to time and a tiny bit of spray, but its only a mist and only after a hundred miles or so, visible on the inside of the hood. Nothing bad and a tissue mops it up for another 100 miles.

I worry sometimes no vacuum there is bad but it only would have vacuum under throttle anyway, so hopefully no big deal. I like not having the muck put back in the carb.

You can see the setup here:

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 Posted: 04-05-2020 03:36 pm
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John Finch
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I used a bicycle water bottle, ran each hose to it, connected with hose barbs and installed a breather filter on the top. Easy access to empty if/when required.

Attachment: Breather bottle.JPG (Downloaded 78 times)

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 Posted: 04-06-2020 01:51 pm
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Ralph H
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I am never ever going to take a photo under my bonnet and post it here after seeing these two photos. In comparison my engine bay looks like it was lived in by a herd of demented water buffalo for a year.

But thank you for the ideas and keep them coming

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 Posted: 04-06-2020 10:18 pm
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redracer
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John: you may wish to have the hose from the engine go as high as possible, or else quite a bit of oil can get thrown into your bottle on hard left hand turns.
Back in stock class in autocrossing, we were allowed to have/make an oil vapor separator, which I did and mounted it above the engine dampener on the firewall.
Still, the best place would be the square on the center top of your large auxiliary oil pump housing.

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 Posted: 04-07-2020 10:51 pm
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John Finch
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I appreciate the heads up!

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 Posted: 04-07-2020 11:18 pm
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Ralph H
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I have located the oil fill canister from my parts car and think I can adapt it to act as an open ended breather. REDRACER - I thought I could mount the canister on its side on the right side inner fender (where the orange box is on John's photo above) with one tube from the block to the bottom connection and a breather filter similar to Discogodfather photo shown here pointing straight up. That would put a new K&N filter at the same level as the air filters. The third opening will get plugged and I already made a new rubber gasket to fully seal the previous twist off filler top. It is pretty high up and if there is any oil it should drain back into the block on acceleration or hills. I.E. self cleaning. Thoughts?

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 Posted: 04-08-2020 12:08 am
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redracer
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You can not mount it on its side, as gravity flows the oil blown into it back into the sump. Ideally, you may want to put it in its original place, which is just to the interior side of the battery(for right hand drive cars, such as in the U.S.). The top should be as high as possible to allow the least amount of oil blow by to get into the canister in the first place.
That canister from the '73 engines was one of the items tey should have kept for the later engines.
best wishes, bruce

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 Posted: 04-11-2020 10:14 am
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discogodfather
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Hey Ralph here are some close ups, the K&N is an off the shelf that fits a 5/8" tube if I remember correctly. Don't have the exact part number. It's about 2.5" in diameter.

Works fine in a street car but not sure what it would be like in any serious action. I would imagine some sloshing and it would leak.




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 Posted: 04-11-2020 09:17 pm
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Ralph H
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Thanks for the photo set. This will be helpful I am sure. Now off to the shops (virtual) to see if I can find the beast.

followup: Turns out there are bunches of them online K&N and others for under $10 with 15mm or 18mm necks Ordered one of the 18 mm units in color matching blue.
Oh so stylish.

Last edited on 04-11-2020 09:42 pm by Ralph H

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