Oops...A Newbie with a serious secondary Vacuum Leak - ZR-1 Net Registry Forums

CANUCK · 06-22-2008

Hello Guys,

I am a 'newbie' in great need of some help...

I took delivery of #438 Admiral Blue 1995 ZR-1 over a month ago. Between really crapy weather and moving into a new home my time in the pilot seat has been very limited.

The car is GOING to be great but right now it is 'ill'. I have a very serious secondary vacuum leak. In my make shift garage with dangling lights and an old kitchen table my Z went under the 'knife'!! I was able to pull the plenum with EXCELLENT advice from the registry. I was also able to find the leak fairly quickly.

The leak is at the output side of the reservoir tank. At the rubber 'boot' on top of the tank a 3 way male connector is attached. 2 of the connection points were EXTREMELY loose and would not hold vacuum. Under closer inspection it was quite evident this condition likely existed for some time as these points had quite a residue build up from air leaking past. I suspect the original owner was unaware!?!

Since it is impossible to effectively clamp these, I decided to try 3M (yellow) weatherstripping to get a seal. On first test it worked. I decided to let is sit for a few days and retest again before putting the plenum on...it FAILED. So instead of being cheap and a hack I decided to do it right and order some replacement parts.

I found a place called White Racing that sells kits. Has anyone had experience with their products as I suspect GM would not stock these vacuum lines and connectors anymore?

My apology for getting long winded here but I am in 'virgin' territory and I hope this makes sense. Now the next BIG question: The solenoid which has a line in and a line out. I put a vacuum on the line in and it holds as expected. The solenoid defaults in the off position so the valve should be closed; hence, a seal?? Now if I put a vacuum on the output side (isolating the solenoid - reverse direction toward the input) a vacuum does not hold. I expected this as in the off position I would think the circuit downstream of the solenoid would need to dump the vacuum closing the actuators??? I notice a foam filter on the bottom of the solenoid switch. Am I correct or is my solenoid switch 'pooched' also? Or is there another way to test it? If it may need to be replaced I see from previous form discussions, jeffvette mentioned it is a stcoked GM part so I'll check with a dealer up here.

Anyway, if anyone has some ideas or advice for me it would greatly be appreciated as I have yet to experience the perma smile of my Z's 405 HP. I sure would like to get it on the road before the snow flies!!

Many thanks,
Doug McMillan

06-22-2008	#1
CANUCK Join Date: Jun 2007 Location: Calgary,Alberta,Canada Posts: 14	Oops...A Newbie with a serious secondary Vacuum Leak Hello Guys, I am a 'newbie' in great need of some help... I took delivery of #438 Admiral Blue 1995 ZR-1 over a month ago. Between really crapy weather and moving into a new home my time in the pilot seat has been very limited. The car is GOING to be great but right now it is 'ill'. I have a very serious secondary vacuum leak. In my make shift garage with dangling lights and an old kitchen table my Z went under the 'knife'!! I was able to pull the plenum with EXCELLENT advice from the registry. I was also able to find the leak fairly quickly. The leak is at the output side of the reservoir tank. At the rubber 'boot' on top of the tank a 3 way male connector is attached. 2 of the connection points were EXTREMELY loose and would not hold vacuum. Under closer inspection it was quite evident this condition likely existed for some time as these points had quite a residue build up from air leaking past. I suspect the original owner was unaware!?! Since it is impossible to effectively clamp these, I decided to try 3M (yellow) weatherstripping to get a seal. On first test it worked. I decided to let is sit for a few days and retest again before putting the plenum on...it FAILED. So instead of being cheap and a hack I decided to do it right and order some replacement parts. I found a place called White Racing that sells kits. Has anyone had experience with their products as I suspect GM would not stock these vacuum lines and connectors anymore? My apology for getting long winded here but I am in 'virgin' territory and I hope this makes sense. Now the next BIG question: The solenoid which has a line in and a line out. I put a vacuum on the line in and it holds as expected. The solenoid defaults in the off position so the valve should be closed; hence, a seal?? Now if I put a vacuum on the output side (isolating the solenoid - reverse direction toward the input) a vacuum does not hold. I expected this as in the off position I would think the circuit downstream of the solenoid would need to dump the vacuum closing the actuators??? I notice a foam filter on the bottom of the solenoid switch. Am I correct or is my solenoid switch 'pooched' also? Or is there another way to test it? If it may need to be replaced I see from previous form discussions, jeffvette mentioned it is a stcoked GM part so I'll check with a dealer up here. Anyway, if anyone has some ideas or advice for me it would greatly be appreciated as I have yet to experience the perma smile of my Z's 405 HP. I sure would like to get it on the road before the snow flies!! Many thanks, Doug McMillan