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Posted by: ezbngreen914 Aug 19 2011, 04:06 PM

I think I almost have this thing back on the road, but noticed something when I was working on the fuel lines. I noticed that the hose between the Cylinder head and the Flashback valve on the passangers side is missing.

What is the purpose of this hose/system?

Its been missing the whole time Ive owned it (10 months).

Is it safe to take it for a short test drive without it?

Man, I'm Jonesing for some seat time but I don't want to mess anything up.

Posted by: type47 Aug 19 2011, 04:13 PM

I think it's basically a vent for the crankcase as the vapor from the crankcase vents through the pushrod tubes, then through the tube in the head, is combined with the same tube from the other head at the anti-flashback valve and from the valve to the air cleaner for the vapors to be burned in combustion. If you don't have a hose connected to the head vent, you risk oil spray in the engine compartment.

Posted by: 914Mels Aug 19 2011, 05:14 PM

Can you take a picture of the engine showing whats missing?

Posted by: SLITS Aug 19 2011, 05:18 PM

Type 47 has the correct answer. One hose from each head (rocker box) to the Anti Flash Back valve and then a hose to the air cleaner. Crankcase breather & emissions control. Valve only prevents a backfire flame from entering the crankcase for prevention of a fire or explosion.

If you don't hook the hose up, you will have oil all over one side of the engine.

If you plug it, you take the chance of blowing seals on the engine (flywheel, front seal, push rod tube seals)

Posted by: Derek Seymour Aug 19 2011, 05:42 PM

QUOTE(SLITS @ Aug 19 2011, 04:18 PM)

Posted by: ezbngreen914 Aug 19 2011, 09:08 PM

Thanks for the info everyone! 914 world to the rescue once again. I think I'll go to the auto parts store and get some hose tomorrow.