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Hello from Portugal,

I am doing a rb25/30det swap into a GQ patrol and I have a question about the vacuum line hookup.

post-127913-0-18034300-1419794527_thumb.jpg

Does this output has the any kind of check valve ? Is it threaded so I can replace it by an AN8 adapter or something. This line needs to be connected to 2 vacuum reservoirs (one for the brake booster and clutch, the another one is to operate the rear locker).

This had previously an rd28t diesel in it, since on a diesel the vacuum is a byproduct of the alternator, I never had to worry about check valves since it only sends vacuum.

Any ideas are welcome.

--

Regards,

Alfredo Palhares

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Diesel Patrols are a bit of a trick as normally their system doesn't see positive pressure.

The clutch booster has a check valve in the actual vacuum hose (check hose orientation) and usually the brake booster has a non return valve at the vacuum hose connection to the diaphragm.

Check you don't mix the brake and clutch vacuum supplies. The clutch supply has an orifice to bias vacuum to the brake booster.

The vacuum tank has no check valves.

I'd be fitting a check valve in the vacuum supply hose, close to the engine.

Use worm drive hose clamps on all vacuum hoses between the engine and that new check valve.

Have seen V8 petrol trucks backfire when starting and blow vacuum hoses off. (in the olden days)

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