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Triumph TR6 - SU Conversion

Hi All
Just installed a pair of HS6 SUs in place of the Strombergs, can anyone who is running on SUs tell me what they did with the breather from the top of the rocker cover,
R. Algie

Ron, my 71 had SUs when I got it. The breather from the top of the valve cover is connected to the bottom of the air filter cover. Apparently, any oil or emissions or whatever blown out the breather hose goes back into the engine that way.

You probably don't need it, but I can email you a picture if you like.

JL Bryan

Thanks John
I'll give that a try, when I first installed them I connected the breather to a spare vac point on the inlet manifold but the vacuum in the engine seemed too high.
R. Algie

Ron-I have pretty much the same situation, having converted to the early ZS used on TR4s'. I tried hooking the hose from the valve cover to the air cleaner housing, but found it didn't keep sludge from forming in the valve cover and also soaked the air cleaners with oil. Maybe it would work in a warmer and drier climate. If you are using an electric fuel pump, a road draft tube can be grafted onto the blanking plate used to cover the mechanical fuel pump opening, sort of like the pre-emission TRs' used. Others have run a hose from the valve cover to a bottle. The pcv used on the early TR6's is also a possibility. Whatever you use, I would suggest checking the inside of the valve cover for condensation and sludge. I guess the best solution would be to use the later SUs' that came with the fittings for the hoses, like the stock carbs.
Berry Price
BTP Price

Ron, I too had HS6 SUs mounted when I purchased my '74 and had the same challenge. I purchased the catch tank with a breather from Speedwell (see link).

Since all the other antipollution stuff has been removed, I refurbed and stored the carbon canister and mounted the catch tank in its place. Run a hose to the valve cover outlet and another small diameter drain to below the car and you are set. My car produces about 6 oz of gunk during our 6 month driving season. Around half of that is condensed water vapour (not antifreeze). Just empty the tank in a gentlemanly fashion - not on your neighbours driveway for example.
Cheers. Steve
Steve C

Thanks folks
Plenty good suggestions there, at the moment I've connected it to the air cleaner box as I don't get much problem with sludge, if I do have problems I'll try the catch tank
R. Algie

Rod Nichols from Idaho went through this last year. Rod, any suggestions?

Rick O.
Rick Orthen

Ron, I haven't noticed any sludge in my air filter box. But it has been extraordinarily dry here in SoFl since I got the car last August. I was told that any junk gets sucked back in and burned, but I really don't know.

Actually, I kind of like Steve's idea. My oil pressure is always pretty high and I seem to use excessive oil, but don't have a bad leak. One suggestion was that my oil is getting blown out of the valve cover or something and his idea would allow me to see. I may try it!

JL Bryan

I really like the stick it back in where it belongs" by way of the fuel pump block off plate. Any ideas where that attachment can be bought?
Don K.

Don - try
Brent B

On my carb-setup, I attached a K&N air breather filter. Seems to work ok, and look good to.
P Johnston

Don--It is my understanding that the block off plates for small block Chevys works. You'd have to tap a fitting on first though.

Rick O.
Rick Orthen

Mine vents to atmosphere via a K&N filter. I have a fuel pump block off plate that was intended for a SB Chev. Fits perfectly wo modification.

John Parfitt
73 5 Speed.
John Parfitt

Rick - the block off plate is a basic size, a one fots all allmost. I was wondering about one with the fitting attached.Thanks . I
ll check out Good parts
Don K.

Sorry it took awhile, but I think an engine that is old and tired, producing a lot of 'by-product' (smoke and blow-by) probably needs the catch tank (mine was a Castrol plastic oil bottle) much more than an engine in a good state of repair. The old parts car engine that I had in for the last 6 months produced a wretched amount of 'crud'....oil & water mixed. That stuff shouldn't be drained back into the oil pan.
I had a K & N filter on the valve cover, & excess pressure, probably from worn-out rings, pushed oil out onto the intake & exhaust manifolds. (that was also with the alloy valve cover, and no baffle , but that was another thread) At that point, I put the 'Castrol catch tank' up front, right behind the headlight. Currently I am running a tube from the valve cover to a T, and to each carb. No big problems yet! I think putting a PCV valve in there would restrict the carbs from relieving that crankcase pressure??? My new engine was seeping a bit of oil out the dipstick tube, and I had a PCV valve in, seeping stopped with removal of the valve.

Next...Aren't there a couple different versions of the HS6? Different emission requirements? Different 'plumbing'?
Did I ask more questions than I answered?

P.S.... great weather in Boise the last three days, drove the TR6 all week! Cool mornings, 60-70 F in the afternoons....Bill, Rick C &'ll get there soon!!
Rod Nichols

This thread was discussed between 13/03/2004 and 19/03/2004

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