Horror

[mattsay]

Just went on a short run with the Weber fitted (car was much better but still not right in my opinion). But, horror, please see attached photo. Loads of oil and I mean loads from the cam breather into the the air filter and down the outside of the carb housing and into the V. Is that why the Strommies wouldn't run properly?

What on earth causes that!

Worried.

Matt.

[mattsay]

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Next picture!

[V Mad]

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Oh dear Matt, that is messy. This is not a new problem; it has been mentioned on the forum before; some cars seem to have more oil splashing around inside the cam covers, and if this is combined with more than average crankcase pressure, the oil is blown up the breather.

Some have used a catch tank, which is a small canister that allows the air through, but also allows the oil to drain back down into the engine. I hope someone who has done it can help with more information.

[alan230752]

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could be your cam cover gauze is f***d or
During normal operation, a small amount of unburned fuel and exhaust gases escape around the piston rings and enter the crankcase, referred to as "blow-by"
[/sup]
[/sup] If these gases remained in the crankcase and condensed, the oil would become more diluted over time, decreasing its ability to lubricate. Condensed water would also cause parts of the engine to rust.[/sup]To counter this, a crankcase ventilation system exists to draw fresh air in from the air filter and expel the gases out the into the intake manifold. In a non-turbo engine, the intake manifold is at a lower pressure than the crankcase, providing the suction to keep the ventilation system going.

If an engine is damaged or enters old age, gaps can form between the cylinder walls and pistons, resulting in larger amounts of blow-by than the crankcase ventilation system can handle. The gaps cause power loss, and ultimately mean that the engine needs to be rebuilt or replaced.
[/sup]Symptoms of excessive blow-by include oil being pushed up into the air filter, out the dipstick[/sup]

[ams]

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Hi,

looks like excesive crankcase ventalation pressure. Possible causes could be at worst excesive blow by caused by a worn engine but more likely if the car runs well, a collapsed breather hose or similar. Or a blockage in the breather system causing pressure build up. Take all your breather hoses off and clean them all through. Ensure the breather system has not been compramised when the carb conversion was done. Did this happen at all with the Strombergs ? Alternativly there could be higher vacuume induction with the new carb thus sucking excessive oil and gasses from the breather system into the air intake. Maybe the inclusion of a filter or valve may be of help. Ask your carb supplier for advice here.

Hope this helps

Andy.

[alan230752]

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alan230752 wrote:

could be your cam cover gauze is f***d or
During normal operation, a small amount of unburned fuel and exhaust gases escape around the piston rings and enter the crankcase, referred to as "blow-by"

If these gases remained in the crankcase and condensed, the oil would become more diluted over time, decreasing its ability to lubricate. Condensed water would also cause parts of the engine to rust.To counter this, a crankcase ventilation system exists to draw fresh air in from the air filter and expel the gases out the into the intake manifold. In a non-turbo engine, the intake manifold is at a lower pressure than the crankcase, providing the suction to keep the ventilation system going.

If an engine is damaged or enters old age, gaps can form between the cylinder walls and pistons, resulting in larger amounts of blow-by than the crankcase ventilation system can handle. The gaps cause power loss, and ultimately mean that the engine needs to be rebuilt or replaced.
Symptoms of excessive blow-by include oil being pushed up into the air filter, out the dipstick

when i had my holley fitted.I fitted an oil catch tank
easy job, cam cover to tank,then into base of air cleaner
although when mine was fitted,It took over 3000 miles to half fill it,
judging by your photos yours would need empting daily
i think you should check the cam cover gauze and do a compression test dry and wet
excessive blow by seems likely

[Stagdad]

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Looks like crankcase pressure due to blowby as already stated but has your camcover got the flame guard infront of the gauze/breather pipe?That may make a difference.Does the exhaust smoke alot with that lot sitting there?some must be going down the inlet.

Cheers Steve

[Stagdad]

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ams wrote:

Hi,

Alternativly there could be higher vacuume induction with the new carb thus sucking excessive oil and gasses from the breather system into the air intake. Maybe the inclusion of a filter or valve may be of help. Ask your carb supplier for advice here.

Hope this helps

Andy.

Andy
I've got the same carb with no oil in the airbox so i don't thinkhigher vacuum is to blame.

Cheers Steve

[V Mad]

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Conversions likemy Weber, and the 4-barrel carbs usually use the air filter to draw in crankcase fumes; therefore there is only a very small vacuum. It is the pressure from the engine that pushes the oil rather than any vacuum pulling it.

Matt: I just had an idea: I think the long 1/2 inch pipe may be allowing oil to be pushed up the pipe; try using a 3/4 inch pipe all the way down to the cam cover; then fit my 3/4 to 1/2 adapter at the bottom end; this may allow oil to drain better; easy to do so well worth a try. Please let me know if this works. If not a catch tank should work.

Thanks Chris

[mattsay]

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Hi Guys,

Nice to hear the brain power!

Regarding Blow-by and compression tests, I did this today. The lowest PSI on any cylinder was 135 and the highest was 150 so I'm in the 10% - just. Most were 140 to 150 so I was fairly pleased with that. This was a dry testwith the engine cold.

I changed to the Weber kit because whatever I did, I couldn't get the Strombergsto run right even though they were "brand new" recon. I changed diaphragms, checked jet heights, float heights, needles, checked for sticking air valves, damper oil, incorrectly adjusted linkages etc etc etc.

The car runs nice when cold (I thought this was an indication of weak mixture i.e. fine on choke) but rougher when warmed up.

Everything HT side has been changed, so has the ignition (Aldon) and Flamethrower.

Although horrified to see the oil dripping (well oozing) into the V I thought that the poor old strommies didn't stand a chance and the mixture was so heavily affected by oil vapour (oil actually). So in a strange way I was actually glad to find a visual problem, only detectable since changing to the Weber.

However, the amount of oil did make me think that the vacuum from the Weber must be far too strong and was more like a wet and dry hoover!

I can only laugh really - almost 8 weeks of great weather and about 800 yards of driving, poorly!

On to the point - would this cause slightly lumpy idle, hesitation on acceleration and generally feel like not running on all8. I thought I had eliminated igniion and fuel.

Is the cam cover gauze an easy fix? I have a suggestion from V mad (Chris) to try too. A catch tank will obviously capture the oil, but will the lack of oneseriously affect the running of the car (I'm not in the slightest thinking of leaving it as is - I just want to solve my poor running at the same time).

Matt.

[flying farmer]

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To get that amount of oil down the engine breather on a short run I would have thought the baffle plate and gauze must be missing from the cam cover altogether:?

I think this is more than just a breather problem, if they are part blocked the oil tends to leak from every seal and gasket, this is more like it is throwing off the cam and straight down the breather. I think you may need to take the cam cover off and have a look inside

A final possibility, is the oil free to drain back into the sump at the back of that head or is it pooling up inside?

If that amount of oil was going into the engine it would give some seriously oily plugs

Neil

[alan230752]

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i may be old fashioned ,but for general diagnosis of engine
a good vacuum gauge works well .if read correctly

alan

[Giles]

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thats interesting Alan - I have never used one - how do you connect it - just to a breather ? I might get one

[alan230752]

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senses manifold vacuum
so connect to pedistal or inlet manifold
alan

[Stagdad]

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flying farmer wrote:

To get that amount of oil down the engine breather on a short run I would have thought the baffle plate and gauze must be missing from the cam cover altogether:?

Neil

This is what i meant when i said Flame guard ,so like Neil said check you have the baffle plate as they are sometimes removed and not replaced after sandblasting to get all the sand out.

Cheers Steve