Checking the Valves

Update by Alan Cesar to the Subaru Impreza WRX project car
May 22, 2013

Our Subaru's sidelined while we repair its engine.
We knew this one wouldn't be much good, but we wanted to check the rest, too.
It's easy to check if your valves are leaking. Just spray enough in to fill the port past the top of the valve, and wait.
If the fluid starts pouring out of your valves, then you've got a leak. All our intake valves were OK, but all our exhaust valves were not.

Why do we use starting fluid to check our valves? For starters, it’s mostly ether, which means you can get a wicked high.

Seriously, don’t do that. It’s a bad idea. You’re likely to kill brain cells and the rest of your body as well. If you use it to get high, we mean. It’s still good for helping start an engine. It’s also good for checking for leaky valves. Remember to properly ventilate your work area if you value your brain cells.

People use all kinds of liquids, from kerosene and gasoline to water. We prefer ether because of its low surface tension, which means it’ll creep past smaller gaps more quickly than many other types of fluids.

A visual inspection showed one of our valves was badly cracked, but we wanted to check the rest, too. It turned out that all our exhaust valves were leaking, but all the intake valves were perfect. If it’s time for a valve job and the engine’s blown up, we might as well upgrade. We ordered up a set of valves from Supertech: stainless steel intake, Inconel exhaust.

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