'62 Olds 98 - PCV vac line
Thread Starter
Registered User
Joined: Nov 2015
Posts: 10
'62 Olds 98 - PCV vac line
Hi all,
I'm replacing all of the vac lines on my 98. I've referred to the 61 and 62 FSM which I have on CD and also trawled the forums. I can't find the info that I need for my scenario.
All of the AC and heater lines were disconnected under the dash, the fuel vac pump was connected round the wrong way and the soft line from the fuel pump was connected to the pcv valve.
The distributor vac advance was hooked into the AC line and onto the carb port.
The auxiliary tank for the trunk release was also hooked into the AC line.
Now I have the vac advance and the dashpot running off the carb port. This is the only small carb port I can see.
I have the trunk release T'eed off the brake booster line.
I have the fuel pump running off the hard line from the large rear carb port that is shared with the brake booster. The soft line from the fuel pump now feeds the AC and heater controls, as per FSM diagram. I've nearly replaced all of the AC/heater lines now, but got fed up with being upside down under the dash for one day!
The one line I have outstanding is the vac line for the PCV valve. This is the PCV valve with the breather tube on the air filter snorkel. I believe that vacuum is required to open the valve.
My FSM only shows the PCV with the adapter plate and check valve as an option or just the downdraft tube.
I've read that the recommendation is to convert to the later model PCV but I don't want to source all of the kit. The plate seems hard to find anyway and I have no other port available for connecting PCV into manifold without the plate.
I just need to get the PCV vac line connected. Does anyone know where this should be connected on a car with vac fuel pump and AC? I'm not sure if the PCV vac line will draw up crankcase vapors that should not be introduced into the advance or AC lines.
Thanks a lot
Les
I'm replacing all of the vac lines on my 98. I've referred to the 61 and 62 FSM which I have on CD and also trawled the forums. I can't find the info that I need for my scenario.
All of the AC and heater lines were disconnected under the dash, the fuel vac pump was connected round the wrong way and the soft line from the fuel pump was connected to the pcv valve.
The distributor vac advance was hooked into the AC line and onto the carb port.
The auxiliary tank for the trunk release was also hooked into the AC line.
Now I have the vac advance and the dashpot running off the carb port. This is the only small carb port I can see.
I have the trunk release T'eed off the brake booster line.
I have the fuel pump running off the hard line from the large rear carb port that is shared with the brake booster. The soft line from the fuel pump now feeds the AC and heater controls, as per FSM diagram. I've nearly replaced all of the AC/heater lines now, but got fed up with being upside down under the dash for one day!
The one line I have outstanding is the vac line for the PCV valve. This is the PCV valve with the breather tube on the air filter snorkel. I believe that vacuum is required to open the valve.
My FSM only shows the PCV with the adapter plate and check valve as an option or just the downdraft tube.
I've read that the recommendation is to convert to the later model PCV but I don't want to source all of the kit. The plate seems hard to find anyway and I have no other port available for connecting PCV into manifold without the plate.
I just need to get the PCV vac line connected. Does anyone know where this should be connected on a car with vac fuel pump and AC? I'm not sure if the PCV vac line will draw up crankcase vapors that should not be introduced into the advance or AC lines.
Thanks a lot
Les
Old(s) Fart
Joined: Mar 2007
Posts: 50,624
From: Northern VA
People stress needlessly over vacuum line routing.
Manifold vac is manifold vac. It doesn't matter if the lines are connected to separate ports or all to one massive tee fitting. If you care more about functionality than optical correctness, the PCV valve, booster, trunk release, and AC can all be connected to the same manifold vacuum port, so long as it is a large one.
Manifold vac is manifold vac. It doesn't matter if the lines are connected to separate ports or all to one massive tee fitting. If you care more about functionality than optical correctness, the PCV valve, booster, trunk release, and AC can all be connected to the same manifold vacuum port, so long as it is a large one.
Thread Starter
Registered User
Joined: Nov 2015
Posts: 10
Joe, I have read that putting the entire vacuum requirement through a single port can affect the brakes. I'm limited by the fitting on the carb.
I could T into the brake line quite easily as it's the same size hose. This would give me brakes, trunk, pcv on one line and the hard line for the fuel pump coming out the side of the same fitting on the carb.
I might try this as it's easily reversible if it doesn't work.
Thanks
I could T into the brake line quite easily as it's the same size hose. This would give me brakes, trunk, pcv on one line and the hard line for the fuel pump coming out the side of the same fitting on the carb.
I might try this as it's easily reversible if it doesn't work.
Thanks
Registered User
Joined: Jul 2009
Posts: 3,187
From: Dallas-Fort Worth
Guys I'm out of town and don't have access to my notes, but I can say the fuel pump vac is for constant steady operation of the A/C and heat system. Mine for whatever has been disconnected to, mine is a non AC 62 car. It was designed that way because of the fluctuation in vacuum off the intake or carb, when on and off the gas pedal. Also if you hook up your PVC line to the line for your power brakes, if you do not install some sort of check valve you could suck oil into your PB booster?? And everything else that your running to the PB booster. My 62 88 is a low compression 2 barrel makes it more difficult due to only two vacumum ports on the carb and do not have seen any on the 2 barrel intake manifold. I have a thread on some of what I just noted about in the 88 section that could help. I will look up this thread for reply's, I will be home Friday and can maybe be of more help.
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