New boat bad motor

[wander1]

Hello
I recently purchased a Catalina 27. It had not been used in 6-8 yrs. The PO said they were told it has a cracked block.
So let the journey begin!!
I got the starter rebuilt,put in a new battery. It turns over and has spark. I hooked up a temporary outboard tank as the extinct fuel filter was full of junk. It turned over and fired once in a while. I checked compression and found zero in 1,2 &3, 4 had 90# ( Auto Zone has a loaner program where you purchase the compression tester and they refund your money when you return it.).
So far the diagnosis is exhaust valves on 1,2,&3 were stuck open. I removed the engine from the boat and have it at home as the boat is at a marina 4hrs away from where i'm at.
I took the head off and removed the valves after much patience spraying them with pb tapping them down turning the engine over with flywheel til they came back up and tapping back down.About 15 or more times until I was able to pry them out.
Thats all for now trying to figure out my next move!!!

[Al Schober]

Welcome to the forum! Sounds like you've made good progress already. Taking the engine out of the boat and doing the work you've done so far is an excellent start and bodes well for your success in getting a reliable running engine.
If you don't have one, buy the Moyer Service and Overhaul Manual. Our host sells new ones, or sometimes you can get one on eBay that already has some greasy fingerprints.
As for the cracked block, give the top of the block a good visual inspection. My experience with cracked blocks is that the cracks are in the area of the valves and are visible to the eye. You may also want to try a liquid penetrant inspection. This involves applying a red dye to the surface then wiping it off. Then a white powder is applied that will pull the dye from any cracks, making a red line in the white dye. These can be done without further disassembly of the engine.
Your next step is to decide whether to do a full teardown, inspection, and rebuild - or just to put it back together and run it. Don't forget to consider the short block option - Moyer Marine sells short blocks ready to go at an attractive price.
Keep us advised - we're interested in how you make out.

[JOHN COOKSON]

A pressure test of the block and manifold would be a good idea since the PO has said the block is cracked. Maybe it isn't cracked at all! Or maybe it is a write off. I never trust what POs say..............
+1 on the Moyer manual.

TRUE GRIT

[edwardc]

+1 on the pressure test. Unfortunately, you'll need to have the head back on to do it.

[wander1]

I did purchase a manual form MM.
I tried to do the block pressure test but I don't think I was doing it right,and didn't have the right parts to do it with.
So I moved on and removed the head and found the stuck valves.
The exhaust valves on 1,2,&3 were so stuck. I don't know if I can ream the guides or if they need to be replaced. The seats on the block and the valves don't look bad. So far I haven't seen any sign of a crack in the block.
Where would I get the red dye and white powder that Al Schober had mentioned.
I thought that if I could get the valve situation fixed and get the engine to run I could see what happens on a stand with a bucket of water.
Any help or advice is appreciated.

Bill

[Al Schober]

Bill,
Reaming the valve guides is not a big deal - all you need is the right reamer. If the guides are tight, they certainly don't need replacing.
I believe all the valve stems are the same diameter, but I also believe Universal used a slightly larger reamer on the later engines (problems with sticky valves?). The early engines also has an oil spray to the lower ends of the valves. So, valve stem clearance is not a 'sacred cow' on these engines.
But before reaming, I'd try cleaning them up. Take a 1/4" dowel and wrap with some 220 grit - if it doesn't fit, take off a wrap. You may be able to remove enough 'varnish' to get the valves to move freely. You can always take off metal - it's hard to put it back on.
The dye penetrant kits are available on Amazon and eBay - perhaps at your local auto parts store. To me, they seem expensive. Before I bought such a kit, I think I'd try some red food coloring and some flour from a sifter (no personal experience with this technique, if you try it let us know).

[sastanley]

My boat came with a stuck valve, and magically, a reamer..I think .316". I've not had to use the reamer, but it seems like a nice tool..you'd also need the valve spring compression tool so you can get the valve out.

[marthur]

I have had good luck with spray carb cleaner to dissolve the carbon and varnish sticking valves in place. Just be ready to change your oil to remove the carb cleaner that runs down into the oil pan before you run the motor.