S14 simple boost leak test how-to

[Si]

Right, as it gets asked almost every week, and I had to test my crapheap, I thought I'd take a few photos and do a quick walkthrough of how to check for boost leaks with the stock WMIC setup.
I've aimed it to be quite simple, as it seems this is often the first thing people have to DIY on 14's!

Tools needed:

• 8 + 10 mm sockets
• Couple of screwdrivers
• A footpump/trackpump/portable compressor thing. One with a pressure gauge is best.
• Some of my other half's gran's plum jam.
• Some Old El Paso Salsa (Mild).
• An RX7 gearbox drain plug.

The last three items are optional. They can be replaced. Basically, what you need is a selection of jars and bungs that can be used to plug the various hoses that need plugging.

It's worth noting that I'm currently running grumpy spec pigeon on my car - as a result, if you have an aftermarket DV, or the OEM one, you'll need to remove it and plug that too.

The four main bits you need to bung up are circled below:


First, undo the two supports that hold the OEM pipework on top of the rad - one bolts to the cowling, the other to the slam panel.

Then, you need to undo and release the throttle body hose, idle air take off, and turbo outlet (and DV if you have it).


Then, bung these with a selection of jars and round things. A jam jar is typically the right size for the TB hose. The easiest way to get to this is to release the jubilee at the other end, twist the pipe round, then do it back up.


The turbo end is sort of aerosol size - a small can of 3 in 1 or small jam jar works perfectly.


The idle take off can be blocked with a big fat magic marker or sump plug.

Bung the DV up as well if it's not already

The next step is to pressurise it. Remove the vacuum line that goes to the stock boost solenoid pipework/Bren device/EBC/whatever, and attach the pump to this.


I pumped it up to about 1.4 bar, then left it, to see if it held.
A solution of washing up liquid and water is dead useful here - pour it over the various joints to find any small air leaks


That's it really Refitting is reverse of removal!

HTH

[sideways14a]

Nice one, i was going to do a write up about this as well (but using a tyre inflater cos i am a lazy 'tard )

Might save my f11 key (boost leak button)

[Si]

Tyre inflator is fine and dandy

I need to find a photo of my little adaptor that I've made that means you can use this method on FMIC pipework without a take-off.

Oh, and as a slight aside - if you find small leak that won't go away with just tightening the jubilees around the resonator pipe (cheers Nissan, for that plastic on metal join ) first try pouring hot water over the pipes, then tightening, and if that doesn't work, wrap a couple of layers of leccy tape around the joints, and tighten - it should keep the leaks at bay

[minwaash]

suprised there isn't a hummus container jammed in there somewhere

[Si]

Note the organic milk

[marko14a]

For a FMIC do you pressurise back through the actuator line?

[thedazman67]

Thats how i pressurised mine. However word of warning on the plugs if they do pop out they do so with some force mine did and hit me square in the chest. Was a bit winded after that and a nice bruise.

[Hesky]

I would do a test with the recirculating DV in situ and also removed, this way you can diagnose any issues which could be related to a weak DV that wont hold boost

[immy21]

This should replace the original sticky, Mods?

[DJFarmo]

Thanks for this idiot's guide to pressure testing the intake system.

My only question is, how did you attach your pump to the vacuum line? Did your pump have a standard car/bike tyre locking valve attachment on the end and you managed to make that work? Or did you have to put something else on the end of your pump to make it suitably fit the vacuum line?

The next step is to pressurise it. Remove the vacuum line that goes to the stock boost solenoid pipework/Bren device/EBC/whatever, and attach the pump to this.

[IrishPaddy]

i had to do this a year or 2 ago... my neighbours were wondering why the hell i had jars of jam and mustard hooked up to the car

great write up

[Si]

The pump I used does both valves - Schrader and Presta. The Schrader (car type) one uses a push on fitting with a thumb lever that locks it on (rather than screw on).

It's the same system that a lot of foot pumps and portable 12v inflators use

[handsomedez]

Good guide, been meaning to do mine for a while

Can I order one jar of your other half's gran's plum jam please?

[200sxs14a/cmk]

very good guide!! well done

[S14aDave]

Just thought i would add..... Be carefull if you have a carbon bonnet!

I did this, then launched a tin of chilli at 10psi straight at the underside of the bonnet, which luckily wasn't carbon

[dread]

Yeah definately be careful when doing this guys. Myself and a couple of mates once did a boost leak check on a Starlet gt and took the pressue up over 2bar, as he runs quite a lot of boost. Needless to say that getting a metal 3" adapter in the face is not the ideal thing to happen to you.

[anton87]

nice guide

[silverzx]

Pictures don't work for me?