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TR6 TR-6 PCV Routing Question

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davidk

davidk

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The charcoal canister on my 1974 TR-6 is long gone. The pcv system is currently routed from the valve cover, thru a pcv valve, to a tee, then to both carbs. Is this correct? There seems to be a lot of oil being sucked into the carbs. Is there a better way to do this? Thanks for your help.
 

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David, looks nice in there. Not sure about those PVC valves, I might go with the one from a "70 TR6 or one from the TR4-250 type from a junker because you will need the bracket to put on your manifold and I would get a new rubber for the vacuum. Hope you don't have too much blow bye to be able to control.

Wayne
 
I think you are right about the manifold sucking a lot of oil vapors. As you may know the port's opening in the carb body is just inboard of the air valve so the only moving part of the carb that the vapors pass is the throttle disc.
I have a 74 as well and there was no OEM PVC valve in the vacuum line.
I did install one to see if it had any effect on the ammount of vapors entering the carb. After a few months it clogged up and restricted the ventillation to the point that oil was spraying up the dipstick. My cue to take the thing off.
I've been told that the oil vapor problem is really bad if one has the after market cylinder head oil feed line.
MAYBE without having that line from the Charcoal Cannister, too much vacuum is pulling on the valve cover.
In other words, instead of drawing from the 2 places (valve cover and charcoal cannister) it is doing all the sucking on the valve cover. /bcforum/images/%%GRAEMLIN_URL%%/rolleyes.gif
 
You want to see oil sucked in???? Switch to a non baffled aluminum cover and then add the auxiliary oil line from the switch outlet on the block to the back of the head.

At least you still have the benefit of the baffle in the stock cover, which is what I switched back to and got rid of that line.

You could also install a Good Parts Oil Separator kit, but you will need to weld a bung in your oil pan to accept the 1/4" pipe return line fitting.

https://www.goodparts.com/shop/index.php?categoryID=8

This is what you will get and that ain't nearly all that came out. I went from one quart every 900-1,000 miles to one quart every 250 miles.
 
As far as a baffle in the valve cover, would a piece of sheet metal, bent to cover the hole with a small amount of clearance (1/4" ?) serve? I could easily make one up for my alloy cover.
 
Yes put a little steel wool type material to use as a filter. At least on the 6 you need to watch your clearances.
 
Saw this setup on a car for sale on ebay. Looks like a filtered breather on the original opening, with a new opening and pvc valve on top of the valve cover. Different, but it may work....
 

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Darrell,

The clearance, as Don states above, on a TR6 is critical and I do not believe that you have 1/4" of room to play with.

Next is the issue of attaching a metal baffle to an aluminum cover. Bolts require holes, which cause leaks and potential to come loose and drop inside engine. Welding aluminum is not for those without experience.

Just remember, if it drops inside your engine while it's running, you could have much bigger problems than the oil issue.

JMHO.....
 
Brosky said:
Darrell,

The clearance, as Don states above, on a TR6 is critical and I do not believe that you have 1/4" of room to play with.

Next is the issue of attaching a metal baffle to an aluminum cover. Bolts require holes, which cause leaks and potential to come loose and drop inside engine. Welding aluminum is not for those without experience.

Just remember, if it drops inside your engine while it's running, you could have much bigger problems than the oil issue.

JMHO.....
Click to expand...

Hi Paul,

I have a 4A, and I believe there is clearance. But good point about the possibility of a bolt dropping inside. I'm planning on venting the line into the air cleaners, so perhaps a baffle/filter there would be better. Or I could use an external separator, but I haven't found a good spot for one yet.

-Darrell
 
davidk said:
Saw this setup on a car for sale on ebay. Looks like a filtered breather on the original opening, with a new opening and pvc valve on top of the valve cover. Different, but it may work....
Click to expand...

Looks like somebody is trying to sell Paul's car!
 
Thanks for providing that picture, davidk. I'm tempted to try that little air filter in line.
If too much air enters the filter and not enough oil vapor, then the oil vapors will build up pressue and cause leaks.
Because of my past experience using a pcv valve, I'll know just where to look! /bcforum/images/%%GRAEMLIN_URL%%/banana.gif /bcforum/images/%%GRAEMLIN_URL%%/banana.gif
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Looks like somebody is trying to sell Paul's car! [/QUOTE]

LOL.... /bcforum/images/%%GRAEMLIN_URL%%/lol.gif

Did you notice the height of the welded flange and the PCV? That looks like it may need a hood scoop to keep it from denting the hood in the rear.

And Don, I got rid of my cardboard radiator shroud this past spring, so you know it's not mine.
 
David K., do you know what that PCV valve that you're using is from?? If you're going to use a non-original valve like that, you need to get one from an engine that is about the same size as the TR6. Several of the guys in our club are using the PCV valve from a Pinto (2300cc), and are having good luck with it. Perhaps the orifice on the one you have is just too large.
 
Martx-5, are the guys you know putting the PCV valve in the original existing vent/ vacuum line?
Or did they add a port like the pic davidk supplied? THANKS.
 
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