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T-Series the copper pipe?

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NutmegCT

NutmegCT

Great Pumpkin
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Could someone explain the differences in the valve cover "ventilation" in these three photos?

unnamed (1).jpg

unnamed.jpg

open pipe.jpg

I assume some air filter change/modification has gone on in the third photo, but can't figure out why that copper pipe is "open to the elements". Was it supposed to have a draft tube going down toward the block? Or is the valve cover (and pipe) just wrong for that style carburetor air filters?

Thanks.
Tom M.
 
Emailed ya, but that chrome valve cover may be aftermarket (or maybe a chromed original), but the vent would've been oriented toward the now non-extant air cleaner box and connected there. Looks like in the first picture the vent does drop down below the engine. I would think that the one in the third picture could be a source of grime in the engine bay.
 
Thanks. So in the third picture, should the valve cover be replaced with one not having that pipe? Or at least, should there be an extension on the pipe like in the first photo?

I'm assuming in the second photo (with the pancake air cleaner), there's no vent pipe.

Tom M.
a/k/a T-series Neophyte (and Digital Troglodyte)
 
The third one has its valve cover on backwards. Oil cap should be toward the front. Here's a picture with stock air box:

TD engine.jpg
 
So ... if the engine has the twin SUs with individual air cleaners ... there shouldn't be a "vent pipe" on the rocker cover?
 
It needs the vent regardless of air cleaner type. That third one is plumbed incorrectly, seems to me. Not sure how the second one is vented; possibly through the oil cap.
 
Thanks. An interesting anomaly!

Take a look at this from an MG parts catalogue (Anglo Parts):

Index says Part 13, MGTD rocker cover.

Rocker Cover.jpg

Doesn't seem to show a vent pipe at all.
 
Things like this happen over the years when guys stray from the original factory hardware. The center pic is vented correctly, even though it has an after market casket valve cover. The first pic looks like an attempt to direct any fumes and or oil weepings over the side. In the third pic, the valve cover is definitely on backwards, not sure what the plumbers elbow is for, LOL. Never saw a pair of those pancake air cleaners that was worth their salt. The TD original oil bath air cleaner is about the best you can get to trap dust and dirt, reason they were so popular on farm tractors for many years. 60 + years is a long time for most of these cars to retain their original equipment, some of us were lucky enough to get a car with everything as factory still on it. I did have to buy a pair of Volks air cleaners on mine, only thing missing. PJ
 
Thanks Paul - so a TD should have the a single oil-bath cleaner, right?

I'm thinking that third photo in my first post, is someone's home-brew modification, adding the pancake cleaners to the carbs, but not knowing what to do with that rocker cover that's on backwards, and should have the pipe connected to an oil-bath air cleaner.

TM
 
A lot of cars trucks and engines in other equipment in the 40s and 50s had oil bath air cleaners, but over time and after parts stores started offering paper air cleaner inserts, a lot of folks went to them so they didn't have the mess when changing the oil and cleaning the oil baths and when improperly told that the paper filters were just as good as the oil bath, there was no contest. Caterpillar and International farm tractors with their massive air cleaners back then had an oil reservoir in the base, be amazed just how much dirt was collected in a short time. PJ
 
Thanks. But why would you want to plug up the vent hole? Shouldn't that vent hole be connected by tube/hose to one of the pancake air filters? So fumes/oil can be pulled into the engine and burned?

The original top-mounted oil mesh filter does that - and the exploded diagram above shows the intake tube at the top of the pancake filter.
 
Tom, the valve cover vent was among the first attempts at pollution control. Suck the fumes back and burn them. If the side vent is clear and breathes normally, there is no need for that top vent, as stated, an aftermarket decorative plug/cover and or a mini filter is available for it. unless of course you want it to be as factory. PJ
 
"If the side vent is clear and breathes normally, there is no need for that top vent"

Thanks Paul. My eyes aren't what they used to be. Where is the side vent?

TM

 
Wow - I'd never have noticed that.

Thanks Paul.
 
The TF has twin air cleaners similar to the first picture, BUT one has a spigot on the back side to connect to a vent hose.
 
Thanks Jim. My post #7 shows a spigot on one of the pancakes. Doesn't that connect (via rubber hose) to the vent in the rocker cover?

TM
 
Probably Valve cover are from MG TC- I have one 1946 TC and the air filter just connect with it-if you have pancake air filters is better to connect a pipe to one
to avoid gas overpressure in the valve cover
 
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