Launchpad McQ's Catalina 30 Atomic 4 Saga

[lat 64]

Hi bill,

Wx in homer is sloppy melty snow .

Im in Fairbanks right now and the wx is not too bad here but it is winter. We got lots of snow so we were snowed in for a while.

@ Launchpad McQ,
I'm curious how this drip/leak think will play out for you because I have for a few years seen glycol drip out the throat of the carburetor. It is evident after long storage periods and has never been an issue when running the engine. Im hoping it's just a gasket but wiling to accept whatever repairs are needed.

cheers,

Russ

[Launchpad McQ]

Well this week I have some possibly good news to report. As Neil suggested, I pressure tested the block and it held 13 psi for over 30 minutes so I'm hoping its safe to assume the "lock-n-stitch" crack repair is not the source of the water intrusion in the oil. (Fingers still very crossed though) After a fairly lengthy conversation with Ken, he hypothesized and I agree the water is very likely raw water that backed up through the exhaust system.

Clue 1: The level of water in the FWC circuit didn't significantly decline when I was running the engine. Given the very milky color of the oil, it appears a good amount of water made it's way in. This was confirmed by....

Clue 2. The first sign of water intrusion was dripping water observed to be weeping from the lower exhaust manifold flange stud. When I disconnected the exhaust/flange from the back of the exhaust manifold, a couple cups worth of water "gushed" out of the manifold.

Clue 3. If a manifold (or block) perforation were the source of the leak, the FWC water level would've gone down. Also, if the crack were in the manifold, the hot exhaust would've turned the leak into steam that would've been observed at the tailpipe. However I was inside the cabin the whole time so I can't say if that were the case.

Clue 4. It's a Catalina 30. The limited headroom above the engine before interfering with the bottom of the galley cabinet necessitates a short exhaust riser. With any extended cranking of the engine, raw water can fill the water lift muffler, then back up the exhaust. "How long was I cranking the engine before it turned over?" Probably longer than I should've with the raw water seacock open.



Clue 5. Although it doesn't exonerate the exhaust manifold, the date stamp is '91 so it's still a pretty "new" manifold by our standards. It looks to be in pretty good shape by outward appearances. It shouldn't be rotten through even if it's had (cough cough) only 30 years of service. I'm still unclear why the exhaust manifold seems to fail the pressure test. My test method could've been flawed.

Next steps:

I've already changed the oil to the extent possible. As Ken mentioned, it'll probably take a few oil changes to get all of the water-contaminated oil out.
I reinstalled the manifold, carb, and exhaust in preparation for another engine run. I'm going to add green food coloring to the FWC water (I still don't want to use glycol until I'm sure I won't need to drain the system again) and run the engine. I'll note the water level in the FWC system to see if it declines or if the oil gets milky again.

[Launchpad McQ]

Hi Everyone,

The latest addition to the saga involves a near miss with 3rd degree life altering burns to my face, and separately, a near miss with a bad eye injury. So as usual, a tutorial on "How Not to Do It." Read on:

While I was still trying to diagnose the water incursion issue, the engine developed an additional problem. When I would run the engine for a short time (to warm the oil enough for the repeated changes) it would stumble and die every time I would advance the throttle. Definitely not the "explosive acceleration" that should be expected from a properly running A-4 as Don describes in his Carburetor troubleshooting video. I was guessing water had also made it's way into the carb. I took the carb off and there was quite a bit of "gunk" in there. I assumed it was water that had made it's way from the manifold but I wanted to be sure the fuel in the tank hadn't gone bad. (It's been over a year since I filled it up last and put a bottle of fuel stabilizer in there.) With the carb removed, I decided to run the fuel pump for a few seconds to take a fuel sample. The only suitable container I had laying around to catch the fuel was a discarded plastic tub from some Trader Joes salsa the night before. Since my Facet electric fuel pump is powered through an oil low-pressure safety switch at the rear of the block, without the engine running I had to bypass it and run a jumper wire over to the positive lead. I ran the jumper wire from the battery to the fuel pump and started pumping fuel while laying over the top of the engine to hold the fuel line into the salsa tub with my other hand. Just as the tub was about full of gas, I turned to see where to move my knee and the jumper wire slipped out of my hand. With my face 8" above an open container of gasoline, the jumper wire contacted the block and sparks shot everywhere. Everywhere, except miraculously not into the open container of gas sitting inches below my face. Say it with me in slow motion: Ohhhhhhhhhhhhhhhhhhhhhh ssssssssshhhhhhhhhiiiiiiiiiii............ Dumb. Dumb. Dumb. I instantly had flashbacks to my Air Ambulance days of transporting burn victims. Face burns are bad enough but inhaling fire instantly burns your esophagus and puts you in a bad place, fast. That was enough for the day.

After trying to shrug off my self-inflicted near miss with catastrophe the day before, I turned back to the water intrusion issue. For whatever reason I was reluctant to remove the exhaust (again) but decided it had to come off. Immediately the water-in-the-oil mystery was solved. I think we can rule out a crack in the block.



Clearly water backed up through the exhaust, into the manifold, and into the engine. Here's where things get a little mysterious again. The water lift muffler is full to a point 6-8" above its top where the section of open exhaust hose is. Couple this with the short exhaust hot section height limitation of Catalina 30's, and water had backed up into the engine. However, this picture was taken after the engine had been been running a couple days prior, not after an extended "dry cranking" event with the through-hull open that would ostensibly explain a muffler full of water. So the question is now.....why? TBD.

P.S. Okay so the near miss eye injury. In my diagnosis efforts I had removed the spark plugs and looked for any signs of water with a flashlight but couldn't see any. To be sure, I connected a remote starter switch and with my open eye trying to look into the cylinder, I "bumped" the starter and.......BAM! A full cylinder of water squeezed out of the spark plug hole at 100psi right to the face. It felt like someone had shot me in the face with a pressure washer. Water went in my eyes, up my nose, in my ears, and I was soaked. I guess there was quite a bit of water in there. After a couple seconds the shock wore off and I couldn't help but laugh. Water was dripping off the cabin roof and had made it all the way up to the V-berth. I wiped the water off my face and noticed....mmmmm....salty. Wait, salty. Yes! Salty! The block only has fresh water in the cooling passages! It isn't cracked! This whole rebuild hasn't been all for nothing! The water is coming from somewhere else! Yessssssssssssss!!!!!!!!!!!

https://youtu.be/Frtea7v6fB8

Click on the video and then imagine putting your face right over the hole