Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Elmstoneboy]

Anybody know what the inch-Hg should be in the vacuum system of a V6 2.6
I want to check mine with a gauge instead of just pulling a pipe off. 

[chrisgixer]

Just wondering how to get the gauge in the system, without breaking into it?

In all the diags I've seen on the vac system, nobody ever pulled a gauge out. All that's really necessary is to confirm the the presence of vacuum at the relevant point, the vac tanks hold charge, and that the multi Rams move and HBV operates, etc.

[Diamond Black Geezer]

I suppose if you have a weak/leaking servo, this would give a lower pressure all along the system - however I have to say I've never heard of anyone with such an issue - the servos on Omegas seem to be pretty 'bulletproof'. Are you hoping to test for a potential air leak?

Can only repeat above poster, so long as there's a vacuum, and it's operating the systems, that's all you need. I'd be happy to tell you my readings tonight, if I had such a gauge, which I don't, sorry.

[Elmstoneboy]

Thanks both for your input.
As I am usually on my own when working on the car, I think it will be lot easier to
look at a gauge while I'm working the accelerator, and checking through the RPM range
as different parts operate, or not, and when switching off the engine, seeing if the
vacuum is being held.
It would also cut down on the amount of skin removed from the back of my hand when
delving into the nether regions trying to remove a fitting when trying to listen for a hiss.
As some of the rubber T pieces and elbows are getting a bit cracked, I want to replace
them and I thought an extra T on the vacuum pipe to a gauge would be OK, and when
finished, just plug the hole with a small peg.
 

[Diamond Black Geezer]

Appreciate what you're saying there. When on your own it's a pain, and I notice having a 2.6 you won't have a 'proper' throttle cable to rev when you're in the engine bay.

I've been in and out of the vac system of mine what feels like five times over over the last month. In the end I replaced almost all the thin vac pipes, and the main servo hose, too, from a breaker. They do get brittle, and the elbows do crack over time, so to be honest I'd be tempted to replace the lot simply as a matter of course. Very inexpensive, even by my standards, I know Rob G has some bits, as will many/most breakers on here.

Do you have an issue - or is this preventative maintenance?

[Marks DTM Calib]

I regularly use a vac gauge for V6 diagnosis and engine diagnosis in general.

It can show a LOT including engine condition.

Having said that, I don't recall the vac reading you should, achieve off the top of my head, it sits in the green on the gunsons gauge

[Kevin Wood]

About 18-20"Hg / 0.6-0.7 BAR is my recollection.

[Elmstoneboy]

Not so much an issue, more of a feeling it's not quite right and this may be the cause, and
a bit of preventative maintenance. Also just a bit of fiddling around.
Engine has only done 64K so checking it out.

Thanks Mark for the info on the Gunsons gauge, I shall order one tonight.

Thanks Kevin for the Vacuum info.

[terry paget]

I fitted a vacuum gauge to my Mini in 1960. They were sold as economy devices, advice was to keep it in the green (high vacuum) section for good fuel economy, never in the red (low vacuum). I soon realised all it told me was how wide open the throttle was, which I already knew.

[symes]

If op wants actual HG/inch reading I can connect gauge to my miggy and report back? as I got gauge on rover that I can use

[Elmstoneboy]

Thanks for the offer Symes, but Kevins info should be enough. 

I have now got a Gunsons gauge, as suggested by Marks DTM and that
appears to cover just about everything.    So just need to get a selection of
good rubber fittings, and give it a go. Can you buy these in mixed kits, T's & elbows?
The wifes Discovery could do with some new ones.

[Webby the Bear]

I've re-read the thread and still cant determine this so sorry if I've missed it....

Where are you going to fit the gauge to get your readings?

[terry paget]

I've re-read the thread and still cant determine this so sorry if I've missed it....

Where are you going to fit the gauge to get your readings?

Put another tee piece in the vacuum pipes to dual rams and HBV, near the brake servo pipe.

[Webby the Bear]

I've re-read the thread and still cant determine this so sorry if I've missed it....

Where are you going to fit the gauge to get your readings?

Put another tee piece in the vacuum pipes to dual rams and HBV, near the brake servo pipe.

Cheers TP 

[Elmstoneboy]

Right first time TP. this will at least tell me if the vacuum is what it should be and if the non-return
valve in the vac tank is working, then as chrisgixer suggested, check the rams and HBV.


Has the vac tank up behind the pollen filter got a non return valve? if so I,ll check that as well if I can get in there.

I've tried the listening method and can't hear anything.
It's one of those things that you just can't let go of until you've checked it.