papa tiger

A stuck open or cooler 150 F. thermostat would cause the dampness in cool conditions. The hotter ford thermostat would warm it, and the wind dampner if very cold would help with warm up speeds. Toasted ! : wallbash:

*91f150*

c hanged the pcv valve today......looks like it had never been changed. pretty gummed up. have yet to drive it since changing it though it seems to idle better.

I've heard the thermostat is a pain to change. Bought the oem one. Any truth in this or suggestions.

*91f150*

engine now seems to be missing while idling......also the the valve cover to airbox hose keeps getting gummed up. Sick of wondering and worrying about this. What do I need to do to set my mind at ease I want to know for sure. Will a compression test give me a solid answer?
Will this work?
http://www.canadiantire.ca/AST/brows....jsp?locale=en

Tote-M-Pole

A compression test will give some valuable info. However, it may or may not tell you where to look. I do not believe the head gaskets are an issue. As far as the thermostat goes, I believe that the OE thermostat is a 192 degree F thermostat. If you have anything less than 192 it could contribute to the white foam you have seen.

With that said, the last 302 I had was in a 87 Grand Marquis. It had the white foam issue on the dipstick and cap you describe. What I found is that underneath the PCV valve is a filter of sorts. It is a cavity that Ford pushed a long length of wire into, it curled up on itself very tightly and acted as a filter. Unfortunately all it would do is collect oil/vapor residue and stop the PCV from pulling vapors out of the crankcase. There by stopping flow through the PCV. I learned this the hard way when crankcase pressure blew out lower intake manifold gasket and I could not stop the subsequent oil leak from the rear of the intake manifold to block interface. When I removed the intake manifold I found this crappy design.

Hope this gives you something to think about.
Merry Christmas

papa tiger

A hot compression test of all cylinders, than let the engine cool down to room temp, then a cold compression test, compare them. Cool test should be slightly lower but all cylinders should be comparable. If not you have an indication of the mechanical condition of your rings and valves. If your gasket is blown between cyls lower compression of them, but a water leak from the gasket may only be noticed with rust on the spark plug or in the cyl itself with a bore scope. Cracks are another story and pulling down and testing them is the way to go. Recharging the battery may be necessary to do all the testing to get good cranking rpm's and accurate records kept of cyl psi comparisons. Very low compression would indicate a major problem in cyls affected and cause poor power. Expensive to fix. :b angin:

*91f150*

wow thanks for all the great information guys, you really know you sh*t. As far as that filer you spoke of tote, is it replaceable, cleanable? if not, when I seafoam the engine like I want to, it couldnt hurt to add a little through the pcv hole, could it?
Anybody know if seafoam is hard on older engines?

papa tiger

Use care, wear gloves, think it is mostly white oil/ kerosene? Some swear by it. Lots of white smoke for a while. Used unwisely it can be not so wise a day. Take your time and be cautious. I prefer to add to gas tank and drive a good day trip into the distance to heat it up good. I love to long trip so carbon hasn't ever been a big deal for me. The stop and go never really getten it on, without any hard day trippen is really a tough one on the old mill.

Tote-M-Pole

91,

You can easily remove this filter. Hopefully Ford has a better design by now. At the time I tried to clean it. It was a waste of time, I bought a new one.

As far as seafoam goes, I have never used it so I will not comment.

*91f150*

how do i clean it, the pcv valve is buried on the valve cover against the firewall

Tote-M-Pole

In my 87 302 the PCV valve was in the lower intake manifold at the back right next to the firewall. The filter thing was just below it. If your PCV valve is in the valve cover I doubt that you have one.