1. Home
  2. General Ford Forum
  3. Oil leak in 91 Crown Vic

Oil leak in 91 Crown Vic

Hello, I have a '91 Crown Vic 5.0 that's developed an oil leak. It's on the driver side and mainly effects the rear half of the block on that side. So far I've eliminated the valve cover as the cause (totally dry) and I don't suspect the oil pan ( I tightened the bolts. Plus the leak seems to be coming from higher up on the block). The oil hits the exhaust system either right above or below the exhaust manifold/exhaust pipe joint. From there it runs down the tail pipe and burns and generally making a mess. Anybody care to take a crack at the source of the leak? thanks, Tom

Reply to
Wallace
Loading thread data ...

Reply to
Sharon K.Cooke

Intake manifold gasket. The rear piece usually gets sucked in because the screen below the PCV valve gets clogged. Make sure you have this screen replaced also.

Reply to
Michael O

The distributor is on the front of the engine.

Check the screen where the PCV valve goes in. It sits on top of the engine in the rear. If that's clogged, clean it. That could be the culprit.

Reply to
SizzleMP

Exactly right. I had the identical situation and it was definitely the manifold gasket. Under the PCV valve and grommet is a tightly packed mesh screen about the diameter of a quarter and a half inch thick. It gets nasty and eventually stops up. When it does, the pressure in the engine cannot be relieved by the PCV and it starts destroying seals. Before I figured this out, it ruined or weakened the intake manifold gasket, both valve cover gaskets and the rear main seal on by '88 Crown Vic 5.0.

CJB

Reply to
CJB

Where is the PCV located on this engine?

Reply to
Mark

At the rear of the intake manifold, center.

Reply to
Michael O

Reply to
Thomas Moats

Does the air intake plenum need to be removed to get to the PCV valve?

Reply to
Wallace

No

Reply to
Bob

Get your head up there with a flashlight, after you see it once, you'll be able to feel for it in the future.

Reply to
Michael O

Of course, it's much easier to install after removing the upper intake plenum, so if you're planning to replace the intake gasket anyway, put the PCV valve in place before installing the UIP

CJ

Reply to
CJB

Thanks to all for the suggestions on the cause of my oil leak. It turned out to be the intake manifold gasket. The valve covers were also suspect so I had these gaskets replaced too.

Thanks, Tom

Reply to
Wallace

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.