?? about vaccum check valves

[87gninpa]

i managed to break one of my old brittle vaccum check valves. its the one right near the oil filler neck ont he drivers side, i think its going to the knock sensor?? anyways, i couldnt find one at any local parts stores and they said to just use a regular vaccum fitting. i put it on, but im afraid to start and drive the car until i know if this is ok. if its not, where can i get another check valve???

 

[zam70]

It goes to the EGR. Knock sensor only has a wire running to it.

Anyway - If it is installed in the right direction (so intake can suck air through it) , it will work fine.

 

[87gninpa]

i understand how the check valve works, but i meant is it ok to use a regular vaccum fitting(flows both ways, no check valve)????

 

[MistaScott]

Not unless you want to blow out your EGR solenoid under boost.

If you run without one, don't boost. They're there for a reason.

You can get a new one from GM or partszoneonline.com. Do a search for two way check valve and you will get the part number.

 

[zam70]

Yep - forgot that part in my post - you have to have a check valve there.

Once again - don't take what a parts counter guy says as fact.

 

[19gn87]

87gninpa...I wasn't able to identify/locate in my parts manual, but I'm thinking it would be next to impossible to find a new one anyhow. IMO your best bet may be to check with G Body Parts or various other board members with parts cars, etc.

 

[MistaScott]

I just ordered some new ones, Delco parts. Part number 14047619. They have an improved design and are smaller than the stockers.

 

[19gn87]

Good job, Scott!

 

[scottyb]

They stock the smaller ones at NAPA.
The local GM dealer showed none of the original types in stock locally, so I just bought one slightly different that has 2 ports on one side. If you need one right away, use one of these.

 

[87gninpa]

the GM dealer actually still has them, but they said theyd have to order them from lansing, MI and it would take about a week. so i went to autozone and they had the exact same thing int he help section, just a little smaller, works perfect
thanks guys

 

[CTX-SLPR]

Howdy,

How many of these little boogers are there on the motor? I'm building mine for basically scratch out of an 87 GN intake, fuel and electronic stuff ontop of an NA 4.1 Block going into either an orginally NA Regal or quite possible a 62 Buick Special.

Thanks,

 

[MistaScott]

Two, one before the EGR and one before the canister. They just prevent boost pressure from blowing the EGR and canister solenoids.

There is also a three-way check valve. Here is how the EGR branch of the vac system looks on a fully optioned GN:

CK VALVE-----TEE-------EGR SOLENOID
................... | ...........................................
................... | ...........................................
HVAC--------3 WAY CK VALVE--------------CRUISE

Ignore the periods, they are just spacers.