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Breather Pipe/Plug

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sail

sail

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In my pile of stuff and somewhere on the to do list is a breather pipe for the crankcase. Question is how to get the plug out of the block? Engine is in the car and once started there will be no turning back. With the pan off is there room to get at the backside?
I assume the valve covers were different from the push on oil fill cap to the eared as I have.
 
Richard,

It's impossible to get to the back of the plug from inside the block. There is a cast channel inside, covering the plug area, to prevent oil splashing into the pipe.

Just take a very sharp chisel, drive it into the plug and carefully pry it out.
Did that on a TR4 engine with no problem at all. Came out very easily.
 
Thanks both, hoped it would pull w/o grinding. Put some blaster on and will go for it later today.
As far as the valve cover cap I would assume it would be best to put on a push on. Does the valve cover have the same flange just w/o the cut outs? I really don't want to buy a new cover.
 
Richard, May I ask, are you going to the road draft tube, or a custom setup? and what is the motivation behind ditching the original PCV setup? Not trying to change your decision, just curious.
I plan on popping that plug on my TR4A motor, but only because it's going in the TR2 and I want it to be correct for that car (Road draft tube), otherwise I'd keep the PCV setup.
 
Richard,

If you are going to do the conversion, I would go ahead and replace the rocker cover since the neck is different where the cap mounts (longer to support the slide-on cap versus the eared twist-on cap).

My first TR4A had already had the PCV valve arrangement removed when I got it and the rocker cover replaced so all I had to do was remove the plug in the block and install the tube.

Scott
 
I did this (removed plug and added the tube) w/o changing the valve cover and got quite a bit of relief from the problem of oil oozing from every seal and pore. I mainly kept the old valve cover for the look.

Slide hammers & chisels will likely work if the engine is out of the car... otherwise you may find there isn't much swing room down there. I weakened the flat part of the plug a bit with a dremel, then was able to punch a stubby flathead screwdriver thru the thing. Can't recall if I used a lever or the side of a ball peen hammer. Once the screwdriver was thru I twisted and pulled to extract the plug.
 
If the PCV system is working right, it should not cause any leakage. A blocked PCV can, and will, cause leaks by causing excessive pressure buildup in the crankcase, But I can't argue with the "Keep it simple" train of thought. Like I said, I was just curious. You can retain the later valve cover and oil fill cap if you want. Once you install the road draft tube, you need to disconnect the line from the port on the valve cover to the intake and block off the port on the intake. otherwise you've created a vacuume leak. this leaves the port on the valve cover with nothing to do. Find a breather filter and slide it right on there. there's your fresh air inlet normally in the older style oil fill caps.
either way, you'll need to re-adjust your carbs to make up for not having the crankcase gasses entering the intake
 
Thanks for the comments. It all makes sense. Good to know I can make the original cover and cap work. I doubt the old style cap will work on my cover with an extension of some sort but got it for next to nothing so worth a look. A new cover isn't in the budget and mine is in good shape. Otherwise I will take your advice and get a breather filter.
Haven't gotten out there yet to work on it. My wife's birthday started at noon yesterday and will hopefully end sometime tomorrow.
 
sail said:
My wife's birthday started at noon yesterday and will hopefully end sometime tomorrow.
Click to expand...
Hehehehehehehe! that sound about right! have fun.
Check the local speed shop for a breather. maybe try Summit if you don't have any luck locally. A nice K&N breather will give you that "race car" look when you pop the bonnett as well.hehehehe
 
FWIW - I left the tubes connected to the air cleaners as I didn't see how anything sucked in there would be a vacuum leak since it is just a bit more air into the air cleaner side of the carbs.

As for the original PCV being up to the job if not blocked -- IMO that little opening in the valve cover was inadequate to let the whole block breathe. This is quite different (and much cruder) than later PCV systems on Triumphs and others.
 
Good point.. I had assumed he has the PCV setup with the big flat valve and the pipe running to the intake, but TR4As also had the setup with the pipe just running into a "y" and then stuck into the air filters. If it's that setup, like Geo said, just leave it and add the road draft tube....
 
Yes I do have the round PCV valve which I intend to take off and plug the manifold inlet.
Lots and lots of filters on line. Will probably check NAPA first.
I hope I just cleaned up the last birthday dinner (crab legs) so tomorrow I can get back at the car.
 
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