Easy wastegate function check.

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Easy wastegate function check.

Postby lotusflasherman » Sun 12.02.2017, 00:05

When I had a 'misbehaving' turbo several years ago I followed the Lotus Service Notes procedure (EC 14 Page 61) to check for 2mm of rod movement when a pressure of 9.8 to 10.2 p.s.i was applied using a pump and gauge.
Since then I've always found using part of that procedure is much easier than trying to 'wriggle the rod with pliers' which seems to be the accepted method. I connect a pump and can easily see whether the rod is moving or not ...
Tried pliers once and wasn't sure if I'd gripped it properly and my hands tended to be in the way to see whether the rod moved. Using a pump also confirms the wastegate actuator diaphragm is OK as well.

All you need to do is unscrew 2 jubilee clips and take off the large turbo to air filter tube, remove the small hose from the turbo leaving it on the wastegate and stuff a pump connector into the hose. Pump and 'hey presto' the rod moves :-D , or it doesn't :( ... A bike pump with a football adapter or a car tyre pump with the tapered airbed adaptor is ideal for the job and easy to get the required pressure to move the wastegate - see photos ....

wastegate bike pump.jpg
wastegate car pump.jpg
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Leave me alone, I think I know what I'm doing.
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Re: Easy wastegate function check.

Postby tb10 » Sun 12.02.2017, 01:43

:clap: :clap: :clap: :clap:

:cheers: :cheers:
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Re: Easy wastegate function check.

Postby GeoffSmith » Sun 12.02.2017, 12:17

Calypso Red S2 #417

USB ElanScan interfaces - £60 incl. UK P&P & £65 incl. ROW P&P
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Re: Easy wastegate function check.

Postby Steve A » Sun 12.02.2017, 18:59

Good job that man :clap:
"If everything is under control, you are going too slow."
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Re: Easy wastegate function check.

Postby Vaughnc » Wed 15.08.2018, 11:36

Glad I found this post - this is a very easy test and helped me eliminate one possible cause (for an erratic boost gauge). Of course the wastegate may still stick when hot, but at least its obviously free moving when cold.
Thanks !
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Re: Easy wastegate function check.

Postby Oscarthecat » Wed 16.06.2021, 00:48

Tried this today and worked a treat. Thanks Phil!
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