Dead Engine. Frozen. Where to Start?

[69reneb]

Just purchased a Coronado 30 with a seized Atomic 4. See pictures. PO did not relay any info on how it died.

I pulled the plugs and their is some rust. Pulled the dipstick and oil is black, but at proper level and no signs of water.

It wont turn over with the starter and I tried to manually turn it over with the flywheel and it wont budge. Tried oil and acetone in the cylinders to free it up. Still wont budge.

I saw on this site many people fixing a frozen engine, but not much details on where to start.

There is an atomic 4 engine for sale nearby for $900 and it is running and has a lot of new parts and rebuilt carb. May just purchase that one and swap it out, and sell the original. In which case, need instructions on best way to dismantle and remove the engine.

I hope to post what help I get and finish the story for others to use. Appreciate any help.

[Dave Neptune]

Welcome future A-4 mechanic

69reneb, first welcome to the MMI Afourian Forum!

How is your access to the starter area? If you can get the starter out and work with the flywheel you can get some real leverage for breaking it loose. My engine was frozen too when I bought it and it is still running today 29 years later now~all original except one exhaust valve! It is well worth spending a bit of time as once freed up the engine may just be fine, I have seen many a resurrection with these beasties.

It is worth making access ports to the engine that you can work "through". Are there any in your Coronado yet?

The carb looks really bad but is nothing to worry about yet.

Get the manual and learn how to reduce your pics to the 600 pixel range for our viewing.

Good luck, Dave Neptune

[ndutton]

Dave has more adventure in his heart than me.

From the looks of the pictures I'd pick up the running A-4 (see comments below). It may need some repairs itself but you'll have a better start point. I would not consider selling the seized engine but rather scavenge the useable parts off of it. If the manifold holds pressure you'll have a spare. Same with things like the raw water pump, starter, carburetor looks doubtful, distributor, reversing gear, head, valves, springs and related parts, etc. Lots of potentially good parts that may come in handy later on. The value of the parts will exceed what you may get for a seized engine by far. And who knows, the seized engine may be resurrected as Dave suggests. If it is you'll either have a running spare or something more valuable to sell.

About that $900 running engine, at that price I'd require a running demonstration and a complete cooling system pressure test. Without both the price drops in half. I'm a cheap S.O.B. Shake my hand on a deal and it's good as gold but you'd better count your fingers.

By the way, what year is your Coronado? Trim tab??

[hanleyclifford]

Neil is right. I sold a running engine for $200 once (half price for a kid). Spend a little time futzing with that flywheel (load the cylinders with Mystery Oil); and watch those fingers. Change the engine oil asap.

[Overdraft]

frozen engine

Well, I'll mostly defer to more experienced hands here, but ....

Last winter I did free up a frozen engine by complete dis-assembly. It is not back together yet.

I think the first question is, are you someone who would enjoy the project of engine rebuilding, or do you want to get back on the water with the least fuss?
If the latter, buy the running engine. Low ball offer and wait for a response.

If you want to get your old one running, then it is likely an involved project. If there is very light rust on the cylinders, then you MIGHT get it freed up by using a pry bar on the flywheel teeth through the starter hole. Remove starter and alternator. On most boats I don't think there is enough room to work the pry bar effectively, so its likely that at the very least the engine has to be moved forward to where there is more room. If you get it free, then it MAY run okay, but I would not be confident in long term reliability.

If you can't free it up, you need to remove head, oil pan and crank, then use a 2x4 inserted in cylinder and judicious application of a hammer to drive the pistons out. This requires removal of engine from boat and dis-assembly.
The amateur mechanic in me says that any time the engine has frozen, then the cylinders should be honed, the rings replaced and the valves ground.
And of course, if you've gone this far there are a few other items you might as well do. See Moyer's book.
Good luck. Cheers, Dave

[HalcyonS]

I don't work for the company but Kroil continues to amaze me. The say it creeps - here's an example. I had an old can, propellant gone, so I decanted into a (nalgene?) laboratory squeeze bottle with a feeder tube to bottom. I kept smelling kroil. Damn stuff was creeping up the 4 " tube and out the spout. No idea what kind of voodoo is in there, nor what it would do to a seized block, but if it were my seized block I'd be soaking it in kroil. YMMV

[sglazebrook]

I've had my Coronado 30 for just over a year now. Access to the A4 is great! The companionway stairs come off for access to the front, go through the galley cabinet for the carburetor and fuel pump (plus), and from the quarterberth for the water pump and reversing gear (plus).

One of the problems with the Coronado 30 is that the cockpit drains are right above the A4, and the drain itself is not a great design (hard to get a drain to fit in the hole in the fiberglass and hard to get a good seal) - mine had leaked all over the back half of the A4 and rusted it completely. My mechanic (before I found this site) told me the A4 was a goner and we bought a "rebuilt" one to replace it. Now that I know better I would have rather spent the time working the original A4 free (especially now that I know what I'm doing(?) and that the access it very easy).

From your pictures there are a lot of things to "clean-up" like bad spark plug wires (cracked boot on #2), the carb and fuel pump, and a few other things like blower ducting (not original as shown) - nothing too difficult. Have you checked if the prop/shaft spin in neutral? Are you sure it's in neutral? You can grab the shifter from quarterberth to shift it into neutral and grasp the shaft from the same position and give it a spin. I had a bad cutlass and gland that made it hard to turn in neutral when I got the boat.

What year is your Coronado 30? Hull number? I'm always on the lookout for them as there don't seem to be as many around as I would have thought.

[Administrator]

Uh, oh.

I can see this thread drifting off into a discussion of convex versus concave meniscuses (meniscusci?), surface tension (the magic of this stuff), the influence of diameter on whether that fluid goes up the tube (and how far), etc.

But not by me...

Neil?

Bill

[ndutton]

Oh no, not me. Talk amongst yourselves. Don't forget about the home brew 50-50 mix of ATF and acetone. It's been proven to outperform Kroil significantly.

[69reneb]

Update

its a 1970 Coronado 30' hull number 110. Has a trim tab, which is disconnected. not sure why. Probably stuck!

I'll try to spin the prop shaft. Trying to deal with one problem at a time! The boat was re-fitted in 2004. Nicely done! Just need to get her running.

Just dismantled some of the engine. Down to the head. Working the oil in to try and get the head off to see whats going on in there. I'm thinking that salt water came back in the manifold and that's why she's froze.

If nothing else, its a lot less weight to haul out.

I bought the running engine for $850. It has almost $600 worth of new parts on it. Electric fuel pump, rebuilt carb, new starter solenoid. I wish I could get a running engine for $200. In CA, the unknown rusty wrecks are going for $400.

I agree that parting it out, might be better, and keeping some parts for myself.

Thanks for all the help. Will update as I go.

[romantic comedy]

I have freed up engines by using a grease gun. I adapted a grease fitting so i could fill the cylinder with grease.

[69reneb]

Questions

I think the ducting was to vent oil fumes out. Its seems like a good idea, but I think the PCV valve would be better option?

Is that a good place to put the negative ground? on the front flywheel cover?

Thanks

[ndutton]

its a 1970 Coronado 30' hull number 110. Has a trim tab, which is disconnected.

I can't remember the hull numbers I built but it doesn't matter, I didn't start until January 1971. I remember the trim tab though, one of my responsibilities. If my memory serves, the trim tab was controlled by a Morse Red Jacket 64C cable, the same as the engine shifter. I'm somewhat surprised your boat has an Atomic 4 unless it's been repowered. We were using Palmer P-60's in the Coronado 30's.

Have you tried moving the tab with the cable removed?

[67c&ccorv]

I think the ducting was to vent oil fumes out. Its seems like a good idea, but I think the PCV valve would be better option?

Is that a good place to put the negative ground? on the front flywheel cover?

Thanks

You had to mention that didn't you!

[hanleyclifford]

That is where I have a ground cable, too. BTW, I'm hanging out with that carb throttle bracket.