300sd switchover bypassed

While getting to know my engine I have realized that the previous owner bypassed the switchover valve coming off of the Alda.
Should I reconnect this? If so, how can I test
to see if the switchover valve is working properly?
1984 300SD Thanks, Jeff
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The purpose of this valve is to prevent an engine runaway. The valve vents the line to the ALDA whenever (hopefully never) the turbo boost exceeds 16 psi. The electric pressure sensor is on the top rear of the intake manifold.
Defeating this safety system creates the possibility of engine destruction if the turbo's wastegate (relief valve) fails to open at its 10 - 11 psi threshold and an instance of full power that drives the turbo pressure above normal limits. The ALDA then would become so pressurized that it would add substantially more fuel to the motor creating more boost pressure and making it run faster and faster until BOOM!
The valve gets dirty and may leak; that creates flat acceleration when the ALDA doesn't get the proper boost pressure. Or, the banjo fitting on the rear of the intake manifold gets clogged with soot (cleaning it is easily done with a straightened paper clip).
You can experience the effect of the ALDA by test driving the car without the banjo connected to the intake. The motor will run fine but acceleration will feel flat; the hissing noise is the turbo pressure blowing out of the banjo hole.
--

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Thanks for the explanation T.G.
Sounds like I should get a new switchover valve, clean the banjo fitting and reconnect everything.
Again, thanks, Jeff
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Has any heard of an engine blowing up from bypassing the switchover valve?
Jeff
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No. But diesels have been known to do so for another reason - running (uncontrollably) on their lube oil.
And let's not forget that these 617.95X are now old machines and have weakened somewhat with age so no drag racing for them!
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On Apr 16, 1:49 pm, "-->> T.G. Lambach <<--" <"T.G. Lambach at NoHamorSpamcomcast.net"> wrote:

Hogwash. I drag race mine every time I can. That is every time I can find a suitable victim. Usually a dump truck or semi towing a wide load. I've only lost once to a dupm truck. That was humiliating. Then he dropped a stone out the back. Yep, he had a full load.
Okay. So maybe I'm exagerating.
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