TR2/3/3A Correct valve cover?

I have a 60 TR3 project and was wondering what is the correct location of the breather cap, front or rear of the engine? I see pictures of both locations. Also I have a spare valve cover with a metal tab welded to the rear of the valve cover with a hole in it. Is this a TR 4 valve cover? Thanks for your help and have a good day!

The correct breather location is towards the front, and it should be a chromed cover. Most 1960's have the small tab at the rear...most likely for a "race" type breather (that would come up from the block instead of the stock "down"). The small tab was eliminated at some unspecified time late in the TR3 production.

The TR4 valve cover had a cap, rather than a breather, and it was located near the rear of the cover.

There were several discussions on the little tab with, as far as I can see, no consensus as to what it was for nor what production runs had it or had not. John's speculation about a racing cap didn't com up, at least in my memory but as plausible as some of the rest.
Tom

TomMull said:

John's speculation about a racing cap didn't com up, at least in my memory but as plausible as some of the rest.
Tom

Click to expand...

Not really my speculation...that's off the VTR's website.

You are absolutely right, John, the speculation was on the part of the experts (who generally got things right). I'd like to see a picture of this arrangement, with the breather tube tied to the valve cover. I went back and found the reference:
"T R AUH-16.
Rocker Cover and Oil Filler Cap.
Except for late TR3Bs, rockers have the oil filler at the front. The late version
has the filler in the rear (like TR4s). The Oil Filler Ca
ps are push-on type and provide "open-circuit" breathing to
the engine with the integral mess filter. Valve rocker cover variations include:
* TS1 Early cover -- painted black.
* Late TR2 Changed to chro
me -- apparently no part no. change.
* TS18230E (ref. SPCEd4) no details
* TCF1 Late version with rear filler.
In addition, early rocker covers had a tab with hole on the rear, distributor side. No details as to when the

tab disappeared or its purpose; the tab may have been used in competition setup where the breather is routed up

and fastened to the tab."

CJD

You are partially correct on the TR4. TR4's up to Engine number CT14233E had the breather style cap like TR3s, but if Triumph had placed the breather at the front end of the engine there would not have been enough clearance between the engine and hood, so they moved the breather the the rear of the engine.

Since early 62 TR4s used the same engine as TR3Bs with Commission Numbers TCF 1 - TCF 2804 (May - Oct 62) they had the breather at the rear also, since that configuration would work on both the TR4 and TR3B.

When Triumph went to the closed system (for emissions purposes) is when they got rid of the crank case breather pipe on the lower left rear side of the engine with Engine Number CT14234E, inserted a plug into the breather pipe hole and went to a different valve cover with a cap that looks similar to a radiator cap.

Visit my website at: https://mysite.verizon.net/vze114b79/id13.html

Vila
1933 Chevrolet
1962 Triumph TR4
1984 BMW 633 CSi

Vila said:

...Visit my website at: https://mysite.verizon.net/vze114b79/id13.html

Click to expand...

Couldn't get that link to work -- I was hoping to learn the purpose of the big brass bolt in the middle of the early TR4 valve covers (the ones with the breathable cap).

All the caps I remember in the sixties on 3's were black with the white lettering (oil names). When my car got stripped circa '69, the thief took mine (along with the battery, top, side curtains, and seat cushions, must have been midnight auto supply) . The replacement breather I got from the Triumph dealer was metallic grey with red lettering. Think the chrome breathers were aftermarket.

Geo

I'm not sure what the issue is with the link, I just got it to open in both my original posting and in yours.

Try a Google search of " EC-130J CSO " and my website will be one of the first few listings that comes up. You may be able to get to it from there. May want to try it soon since Verizon just notified my they are discontinuing the free website service to customers and the site will be gone in a month or so.

As far as the large brass bolt in the TR4 valve cover. I have read that since Triumph sold their engines to other manufactures, and some used this threaded hole, they just put the threaded hole in all the engines and installed a plug when it was not needed. A year or so ago I saw some photos on the internet of other brand British cars from the era that appeared to have a Triumph engines. One had a copper pipe with brass ends that went from the threaded hole in the valve cover back to the base of the carburetor where vacuum hoses are normally connected and the other had a rubber hose connected that when to the air cleaner. The cars had a different intake manifold with a downdraft carb.

Vila
1933 Chevrolet
1962 Triumph TR4
1984 BMW 633 CSi