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Daurie
11-27-2008, 09:19 AM
Quick question about my PCV system. I have the Sealed oil tube cap and sealed valve cover breather that attaches to intake elbow. PCV valve between carb and oil fill tube. What's happening is when I pinch off the line going from the PCV valve to the oil fill tube engine dies. Lots of vaccum on this line. I have a little vaccum on the line going to the valve cover breather cap. When I remove dipstick, orange oil fill cap or oil fill tube cap I get high idle. I removed the PCV diaphram and it is in perfect shape. Air will flow through the PCV valve going from oil fill tube into carb base. Air will not flow from carb base to oil fill tube. I don't know exactly how the rover system is designed to work but it seems like I have an excessive amount of vaccum in the engine. Engine runs well and idles smooth otherwise.

Happy Thanksgiving!
Thanks,
Daurie.
Daurie
11-28-2008, 03:56 PM
anyone??
LaneRover
11-29-2008, 06:59 AM
My only thought is that why would the engine die by pinching off a PVC tube? To me that says that you are not getting enough air through the air intake.

Does the truck run fine when driving down the road? Is everything else stock with the oil bath air filter or do you have an aftermarket airfilter on it?

Brent
Daurie
11-29-2008, 07:53 AM
Everything is stock. The engine dies when I pinch off the line only at idle. I can bring up the RPM and everything runs fine with it pinched off. The breather on the valve cover flows air with no restriction. Still scratching my head on this one. Thanks for the reply Brent.
LaneRover
11-29-2008, 08:01 AM
Does the PVC valve from the oil fill tube go to the base of the carb? I re-read and I think the answer to that is yes.

Does the PVC from the oil breather cap go into the elbow before the carb? Again I re-read your original post and I think that the answer is yes.

If so then that would explain why you have a lot of air going through one PVC tube and not so much going through the other IF there is a problem with air flow at idle in the carb. Then the one at the base of the carb would be providing nearly all of the air to the engine under idle and thus be why the engine dies when you pinch it off at idle. I would check and see if the butterfly valve has slipped (not sure if it can) or see if there is anything else that would restrict airflow at idle but not at higher RPM's.

Brent