Inliners International Forums General Discussion Engines '55-7 235: Mice made me a 10quart milkshake, advice?

I bought what turned out to be a '50 Chevy Fleetline (has a '49 grille) last week that has a fair body (crappy old bodywork aside) and runs pretty nice, because for $200 I figured I couldn't go wrong. Turned out the engine is a '55-'57, I haven't looked for a serial to ID the year yet but thats what the casting number is.

The car hasn't been on the road since 1971, and has only been driven enough to move it around here and there since it has no brakes. But it does run nice and quiet, the points are slightly burned so it's a little rough, but no obvious signs of trouble.

Well, I never checked the oil until today and what I got was milky brown. So I drained it. The pan that normally is 1/3 to 1/2 full with 4 1/2 quarts was close to overflowing with about 10 quarts of milky oil and water mixture. I think the only reason it's not more full is any more than that would go out the draft tube. There were like chunks and things in it, too.

So then I figured I would pull the valve cover. I had already noted drops of water condensated on the rockers through the oil cap. That cap is new chrome where the rest is typical untouched old engine compartment.

So here is all this fuzzy crap all over the head, around the pushrods, etc. It looks like maybe it sat with no oil cap and a mouse built a nest in here that wasn't found until after the motor had been run.


So I am wondering if this is a sign of a cracked block or head? Thats an awful lot of fluid in there. There's no way to check through the radiator for bubbles, etc. right now b/c the water pump is bad - I had to put a bucket under the front to catch leaking coolant - but I have a used '55 water pump I could probably put on there to use to test it and just fill it up with plain water. That and some fresh oil and I run this off a line to a tank for 10 min aught to confirm me one way or the other.

Any advice on if I should mess with this to confirm if it's bad, or maybe try and change the oil 3 or 4 times and see if it clears up? If not, what about another engine?

I'd just as soon keep an inline in this, but given the newer I go the easier it will be to find a runner, how new of an engine can I use with the stock front mounts? Hopefully this has a '55-'57 bell and I can switch to a T5 later on.


Thanks a bunch -

Bill K.

Looks like I can put in pretty much any 235 or 261 through '62 or so if I need to. If I'm going to change it, may as well get a 261. I looked one over in a '61 Chevy truck and if I take the spacer off the fan it will fit the same - radiator is in the stock position on this rig and it all fits, just really close. Maybe I'll put a flex fan on there. So now I just could use some opinions on if I can save this motor or not, before I go through a case of oil and try and add a filter to it -

Since I first posted this I found a guy with a personal page telling of finding "a lot of water in the oil" in a '52 Chevy pickup that had sat for about 10 years, though he didn't say how much "a lot" is and doesn't seem to have an e-mail anywhere on the site. I am thinking about checking some cars in the junkyard (pulling dipsticks) and see if I find another one with a similar oil situation. Maybe the 235 I pulled my used water pump from...

Obviously sitting that long water can accumulate in a lot of ways. If it was me I would just pull the motor and tear it down to check it. If you can purchase a known good 235/261 for a few hundred bucks and don't need to rebuild any time soon I would do that.Or just rebuild the 235(more expensive).

Dear Bill;

With the pan full of water there's more wrong than condensation. First pull the head & have it checked while paying close attention to the head gasket.

You may get lucky.

Rarely do those blocks crack & when they do It's on the outside.

Good luck, John M., #3370

I think what would help is if I could find a way to tell if this oil has just water, or water and antifreeze in it, although I think it must be both or the water would seperate out of the oil. The cooling system has antifreeze, however weak it is, in it now. I'm thinking since I need to change the water pump to test anything, maybe flushing it out and filling with plain water, filling the oil and going from there might give me some answers.

I think if it's cracked, it will be from freezing, in this climate it gets as cold as 20 below at times in the winter.

As for engines, between the yards I go to and my one buddy I could probably check over 50 of them, priced from free to $75 or so, but finding one that turns over and doesn't have the same problems as this will be a crap shoot.

Change the oil and temporarily replace with a brand with no dyes added to it (some oils do have dyes). Empty/flush your cooling system and replace with plain water. Briefly run your engine -- allow it to warm up and then cool down. Take a sample of the cooling system water and put in a jar. Also remove the oil dipstick after the engine has run and smear the oil on the end onto a clean surface and put that to the side. Go back to the parts store and buy some fluorescent tracer dye and add it to your cooling system. Before running the engine take a small sample of the new dyed water and compare it to your earlier sample. Use an incandescent black light (UV) that you can get from the local hardware store. You should be able to distinguish the new fluid from the old via the dye. Also, you should be able to see that the fresh oil smear does not already have that dye present. If you can see that the dye is not already present in both the old sample of cooling water and fresh oil then proceed to let the engine run and fully warm up and then idle for an extended time.

Let the engine cool down and remove the oil dipstick. Smear the oil on the end onto a clean suface and examine with the black light. You are looking for the presence of the fluorescent tracer dye that you put in the cooling system. If it is there then there is some sort of leak between the two. That is not a 100% certain test if you don't see the dye (there might still be a leak that needs the engine to be under load to show up, etc.).

Hope that is useful...

Kevin