The Stovebolt Site Forums The Shop Area Engine Shop Water in engine

We had a storm the other night. My truck is in the driveway and exposed to the rain. I popped the hood last night to see a puddle of water sitting in the oil cap. The valve covers of these old 6 cylinders are vented, not sealed tight like a modern engine. I see 4 vent holes on the top of the cover. I assume the water came through the seam down the middle of hood. How much of a risk is it that water could leak in on top of the valve cover and down into the engine through the vent holes/slots?

it is quite likely. The amount of water would be the question. If you are uneasy about it, remove the valve cover for a look,soak up any water with paper towels,drain the oil without starting the engine. Fresh oil,and you are done. Any remaining moisture will evaporate at operating temperature

Did you leave the hood open?

Check the hose from the front cowl vent. Could be turned directly toward the valve cover instead of down the firewall

I did not leave the hood up. I think it had to come through the seam in the hood.

mine will drip through the seam a bit.

I am reviving this discussion to see if anyone else has come up with a solution to this. After watching it for a while now I am 99% sure the water is coming through the seem in the hood and leaking on top of the valve cover. The design of the cover allows the water to puddle on either side and fill up to the point it looks like it could or is running into the vent slots in top of the cover. Has anyone separated the seam of the hood before and reassembled it? I was considering trying to pull the two halves apart and reassembling after adding a bead of silicone to seal the seem. Is this a mistake? Will I ruin the hood if I separate the two halves? Can the two halves be separated? Any other suggestions? I don't want to have to pull the cover and dry out the top of the engine every time it rains. I can't be the first bolter to have this issue.

If you use a sealer on the seam, don't use silicone. Use a urethane type that is paintable! They make some clear spray-on sealer called Flex Seal "as seen on TV". I bought some at Lowes but ended up not using it and took it back. You might spray that on the under-side of the seam, under the hood.

Make a deflector about 6" wide and attach it to the underside of the hood under the seam. If you put a little radius in it or even a slight V bend the leak, if any, will stay away from the valve cover. Then you can deal with water dripping onto the distributor cap.
Jerry

Good idea. That is a lot less risky and labor intensive than pulling the hood apart would be. I will make a little umbrella for the distributor cap.

I would be concerned with oil getting in the engine but not much about a little water getting on the dist cap. I had a 1950 DeSoto with a louvered hood. It was our daily driver. (I live in Seattle so, lots of rain!) It got plenty of water on the dist cap as well as on everything else under the hood, we never had any issues with it from water.

Yea, even without a leaking hood any car has the potential of getting a lot of water splashed on it while driving in the rain. The small umbrella was my poor attempt at being funny. Why make one? I am going to save one from my next fancy cocktail.

Just make sure you don't drive a Jag XKE. Those things would drown out the ignition if somebody spit on the sidewalk two blocks away! Of course, they DID have a Lucas electrical system, and the Brits drink warm beer because they have Lucas refrigerators!
Jerry

My solution was to purchased one of the vintage C.A.W. cast aluminum valve covers and a vented oil fill cap. The valve cover is bath tub. no water or crud can get in it. The cost was worth the $. There always is one on Ebay. The Wayne, Offenhauser, Fenton.etc valve covers are cheaper but at the moment not in production. I made some inquires and Offenhauser broke their mold and MAYBE be back up in 2017. The caw looks more original not too flashy, with a little history.

It's also possible to flatten the vent slots and TIG weld them, then go with a vented oil fill cap.
Jerry