Mattman928

Has anyone run a full vacuume test on their shark? If so, how does one do it, and what should the test look like?

I was thinking about pulling the vacuume hose from the check valve at the brake booster, and then pulling a vacume on the tube. If this is the right path, how much of a vacuume should I pull, and how long should the vacuume hold for?

Nicole

When Docmirror did it on my car, he worked his way from the check valve to the 40way connector, to each of the lines. We quickly found two areas leaking - the vacuum reservoir line and the climate control line.

The vacuum reservoir itself was not the problem - it turned out the line wasn't pushed in deep enough - a relatively easy fix.

The climate control line leaked at the plastic connector that is plugged into the rubber vacuum manifuld in the center console.

Since both were fixed, the car is like transformed. Much smoother in all respects. Totally awesome!

docmirror

AS mentioned, I've pulled vac on several 928s. I think you are talking about the vac for the accessories. If you have the Mighty-Vac kit, you would use the mighty-vac on the line from the engine that goes TOO the four way splitter. the mighty-vac mimics the engine manifold vac and you should be able to draw about 14 inches. If the system is in good shape it should hold near what ever reading you get for at least one minute. This is a very rough estimate, and less than that might be okay. A perfectly sealed system will hold for quite a while.

insure the test includes the check valve, as they are known for failing. Fixes in this area have a direct effect on the idle operation, and won't be noticed much above partial throttle. If you find a leak at the four way, just start blocking off circuits one at a time until you've identified the leaker. Then follow that back to the valve or canister, and check that independently with the mighty vac.

Doc

khalloudy

Doc,

do you have a detailed full system (both) vaccum test in steps? that would be good as i suspect leaks in my car too, and you're a little far to bring my car to you

Sincerely,

toofast928

The web site below shows some simple Vacuum gauge readings that may be helpful.

http://www.secondchancegarage.com/public/186.cfm

SharkSkin

Basically it's a process of isolating bits of the system till you find the one that's leaking. Pump down a section, see if it holds. If not, try to further isolate the problem. If it holds, move to the next section. I just pumped down the whole system past the check valve, found that it held vac regardless of HVAC control or door lock position for over an hour, and left well enough alone.

That link looks like a very informative one to pass along though, thanks!

IcemanG17

I found Pirtles site and Tony's site very helpful in tracking down vacuum leaks/problems

http://members.rennlist.com/pirtle/svc.html
http://members.rennlist.com/v1uhoh/