Oil Immersed Exhaust Valve springs

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denisj
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Oil Immersed Exhaust Valve springs

Post by denisj »

I vaguely remember reading a thread on this here
I’m working on a Triumph motorcycle engine and was hoping to refresh my memory on the logistics of this idea.

My searching came up with nothing. Anyone know where the inf is?

Have you done this?
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Re: Oil Immersed Exhaust Valve springs

Post by englertracing »

To do this you can,
A make a cup around the valve spring,
b put a tube in your oil drain, and drill a small hole in it so it drains while shut off, preventing valve cover leaks, and allows you to remove the valve cover without spilling oil everywhere.
On ohc bikes you might have to dam up the cam chain passage around the cam bearing making it attain a level before spilling over

In any case you need to take into account how much oil will be trapped when running.
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denisj
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Re: Oil Immersed Exhaust Valve springs

Post by denisj »

Thanks for these tips

I am also wondering if there is any adverse effects in doing this in a touring format or if it is best left for racing
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Re: Oil Immersed Exhaust Valve springs

Post by hoodeng »

What year Triumph are you dealing with?

Cheers.
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Re: Oil Immersed Exhaust Valve springs

Post by denisj »

1970

I would also be applying this to a 78 T140 and a 70 BSA A65
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Re: Oil Immersed Exhaust Valve springs

Post by hoodeng »

You really dont have a way of damming with those heads, making a cup type lower retainer will retain some oil, but the angle they are on is going to work against you and the oil will just tip out of the retainer instead of agitating. Good quality valve springs are probably more important than trying to create an oil bath.
There are a couple of other guys on this forum that work with early Triumph BSA type engines.

Cheers.
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Re: Oil Immersed Exhaust Valve springs

Post by denisj »

I can see the BSA being difficult

With the Triumphs i think I can make the pushrod tube longer forcing the oil to have to fill the rocker first

Here are pics of the stock Triumph goodies
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Re: Oil Immersed Exhaust Valve springs

Post by MadBill »

denisj wrote: Mon Sep 02, 2019 3:08 pm Thanks for these tips

I am also wondering if there is any adverse effects in doing this in a touring format or if it is best left for racing
There's really no need/value for any spring cooler mods in such an application. If you're concerned about spring durability, there are many higher grades of springs that can handle far more RPM and lift than any stock or typical replacement grade parts.
Felix, qui potuit rerum cognscere causas.

Happy is he who can discover the cause of things.
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Re: Oil Immersed Exhaust Valve springs

Post by denisj »

It seems to me keeping this location cool woild be benificial overall
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Re: Oil Immersed Exhaust Valve springs

Post by pamotorman »

oil does a lot to cool the valve spring as I saw a movie of a test done at the GM tech center. the stock block chevy engines test running at indy were losing valve springs in just a few laps. GM did a dyno test where they could shut off the oil to the top end and with see thru valve cover you could see the valve spring turn red after just a few minutes of running with out oil. this is where the valve spring oil spray bars in the covers came from, the "G" forces in the turn at indy was preventing the oil from reaching the springs and causing the valve spring to fail
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