Boost Gauge Question.

[the godfather]

OK. My boost gauge was installed (by someone else) and it didnt work. I have now replaced it and wired it up myslef. It works. But! I say but! Having been plumbed by the SAID expert, the gauge goes down instead of up. Being it is tapped into the vacuum line. Is this correct? It reads between 15-18 wich is about right. When I rev the engine the pressure drops to 15.
What is with that?
I am confused!

NOTE: It is a RaceTech gauge. Electronic type with the sensor under the bonnet.

[MudRunnerTD]

What engine is it on?

[Ben-e-boy]

I have never seen a boost gauge tapped into a vacuum line. mine is just above the inlet manifold

[the godfather]

ZD30 Engine...the grenading model.

[YNOT]

There is no vacuum line you can tap into on a ZD30 to get a boost reading, you need to get a fitting welded or brazed onto the intercooler outlet pipe.

Tony

[the evil twin]

15 PSI is atmospheric pressure (well 14.7 nominal) so I am with Tony in that it's maybe not plumbed correctly.

If the sensor is in any small dia rubber tubing on a ZD30 then it sure isn't measuring boost. The ECU boost sensor is on the Intercooler and most people opt to plumb into the Intercooler outlet pipe for aftermarket gauges

[the godfather]

Thanks guys. I will weld a socket in and get it sorted.
I guess that will teach me for getting so,meone else to do what I should have done myself the 1st time eh.

[patch697]

Thanks guys. I will weld a socket in and get it sorted.
I guess that will teach me for getting so,meone else to do what I should have done myself the 1st time eh.

We've all suffered from that once or twice mate........... Never a good thing when you part with your hard earned for the privilege.

Post up some pics of your mods when you get them sorted mate.

[Ben-e-boy]

whats wrong with drilling and tapping a fitting in guys

[the godfather]

whats wrong with drilling and tapping a fitting in guys

I will be looking at tapping a thread 1st. Will depend on how thick the wall is.

[patch697]

I will be looking at tapping a thread 1st. Will depend on how thick the wall is.

Its thin wall so I'd be welding a boss to it so you'll know its going to stay there.

Good piece of mind I think.

[the godfather]

Yep just checked. Way to thin for a thread so will have to be a weld.

[MC97GQ]

Just a thought,

If it is too thin to tap, you might actually be better to braze or silver solder unless you have access to mig/tig equipment. I wouldn't try a standard stick welder you would probably blow a bigger hole.

Just a thought

Mark

[the godfather]

Yep. I will most likely have to braze it anyway. I have a million brass fitting and no steel ones...lol
Either way though, I'm a fitter welder by trade and do it for a living. But if your not well practiced I agree...get a mate to do it.
And if you are in WA, I just might be that mate.

[robbo0001]

Gday guys,
in the process of fitting a boost guage, and Pyro, to a 2.8TD via a pillar post arrangement..The kit came with the fiting lines for a 3 litre( I think) that incorporates a vacuum line "T", a small filter element for trappibg moisture, a "black box" that the guage wiring and the air sample line hose goes to...having plumbed this in and no result, I am looking at brazing a fitting to the intercooler pipework.

So is it
1. the pipe directly OFF the turbo to the intercooler...or
2. the pipe OFF the intercooler to the intake manifold?

Which pressure reading is more relevant to engine maintenance?
I know its a 2.8 and not a 3 litre, but I really miss not having a Scanguage to be able to monitor the engines stats under different conditions..so any diagnostic ability is a benefit, in my eyes.

Wherever the fitting is brazed, I then hope to run one piece of vacuum tube to the "black box" inside the engine bay somewhere.

Cheers

[NZDaz]

2. The pipe of the intercooler. Both would work but the second gives the pressure at the intake - assuming there is a few psi drop through the intercooler.

[robbo0001]

Cheers mate...will get it mounted next week.

[the godfather]

Well. 8 months down the track and I finally got around to welding a steel socket in to the intercooler intake pipe and plumbing my boost gauge in there. Works a treat. I was going to go on the out let side but had second thoughts due to ease of access on the inlet side. I do recomment that if you do this your self make dam sure you clean it out thouroughly. You dont want any nasties getting in either the intercooler or the engine. I took some pics but cant post them, from here at work.

[the godfather]

Some pics of it being done.
04052012(001).jpg04052012(003).jpg

EDIT: Dam it, I can't load the pics

or can I.

http://www.nissanpatrol.com.au/forums/attachment.php?attachmentid=15884
http://www.nissanpatrol.com.au/forums/attachment.php?attachmentid=15885

[mudski]

By the looks of your IC it needs a clean out and weld up itself...

[the ferret]

Just get the old bike valve, drill the hole and fit it with the lock nut and washer, no welding and fit the hose to that!!.
Cheers, the ferret.

[Cowboy]

Can I ask a silly question here ???

What is the difference between Boost Gauges for petrol and diesel engines ??

I noticed in Supercheap yesterday that they had the Calibre Digital Electronic Boost guarge on special for $40.00, but it says it is only suitable for petrol. I was going to get it, until I read that...

Cheers

Rick

[the godfather]

By the looks of your IC it needs a clean out and weld up itself...

I assume you mean the intercooler. It has a very slight leak, as they all seem to after a while. Looking at changing it up to a larger unit.

[mudski]

Yeah mate, thats what I was refering too. :) I just took all the hoses off my ZD30 and to my surprise they were all spotless inside. No leaks, or that i can't see on the IC too. Still gotta get this Provent fitted though.