Catalina 30 MKIII Major Engine Maintenance

Jan 24, 2009
7
Catalina 30 MKIII San Juan Island
I think I have a leaking oil pan gasket. I can't imagine that it is possible to fix this problem without removing the Universal M-25XP. I can't imagine removing and repairing the Universal M-25XP without removing the galley cabinetry above the engine. But... the Corian countertop is one piece and continuous from the companionway, around behind the stove, and all the way past the sink to the end of the island kitchen. I have seen the videos of people taking the older style wood cabinet off to get excellent engine access... did not look like a fun job, but looked doable. I literally have no idea where to begin to address this problem. Any thoughts/ideas/links/videos are MUCH appreciated.
 
Jan 4, 2006
7,817
Hunter 310 West Vancouver, B.C.
Have you tried tightening the pan bolts when the engine is smoking hot. Like running it flat out for an hour or more. The gasket may soften somewhat.

If that fails, any way to drop a couple of cables vertically down to the engine and lift. All you're looking for is about 6" of clearance to get under the engine.

And after that fails, any engine supports on which you can lift from underneath using small pneumatic envelopes or jacks ?

I've looked with fear at my Yanmar in the past for your exact reason and have a plan without destroying half the boat in the process. Maybe only a quarter. Sorry I'm not familiar with the Universal M-25XP but I don't envy your removing that much interior cabinetry. Not a pleasant thought.
 
Sep 24, 2018
4,752
Catalina 30 MKIII Chicago
Maybe drop the pan a 1/2" and slather the surface with RTV or gasket maker? If there isn't clearance under the engine, maybe mark the height on the engine mount screws, raise it up, take care of the work and then lower it back down?

I've looked at this absurdly large and presumably delicate piece of corian multiple times wondering the same thing. The best ideas I've come up with are an oscillating tool to break the epoxy holding it to the counter top. You can also cut the counter top at an appropriate spot You can add a T shaped transitional piece to hide the gap or fill it in with your favorite caulk or epoxy during re-installation
 
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Jan 11, 2014
14,211
Sabre 362 113 Fair Haven, NY
Other than seeing oil under the engine, what symptoms do you have that suggest an oil pan leak? Oil pressure switches are a common leak source and rear main seals are also a common issue.

If the engine needs to come out, sliding it forward before lifting it up may be the way to go.
 
Jan 24, 2009
7
Catalina 30 MKIII San Juan Island
Other than seeing oil under the engine, what symptoms do you have that suggest an oil pan leak? Oil pressure switches are a common leak source and rear main seals are also a common issue.

If the engine needs to come out, sliding it forward before lifting it up may be the way to go.
I was able to use a small mirror and flashlight and could see oil along the top edge of the pan and oil droplet on one of the bolts. That is why I think the oil pan might be the source. The pan looks corroded, as well & have read that pin hole leaks can develop. That said, I do not have a ton of experience with this type of problem solving. I will have a look at the oil pressure switch next time I am on the boat. Where is the rear main seal?
 
Jan 11, 2014
14,211
Sabre 362 113 Fair Haven, NY
Where is the rear main seal?
The rear main seal is at the aft end of the crankshaft where it exits the block and attaches to the transmission. The leak will show up around the bottom edge of the joint between the transmission and the engine block or the joint between the bell housing and the transmission. From these points the oil can seep along the engine and show up elsewhere.
 
Jan 24, 2009
7
Catalina 30 MKIII San Juan Island
Have you tried tightening the pan bolts when the engine is smoking hot. Like running it flat out for an hour or more. The gasket may soften somewhat.

If that fails, any way to drop a couple of cables vertically down to the engine and lift. All you're looking for is about 6" of clearance to get under the engine.

And after that fails, any engine supports on which you can lift from underneath using small pneumatic envelopes or jacks ?

I've looked with fear at my Yanmar in the past for your exact reason and have a plan without destroying half the boat in the process. Maybe only a quarter. Sorry I'm not familiar with the Universal M-25XP but I don't envy your removing that much interior cabinetry. Not a pleasant thought.
I have not tried that, but it seems like a bunch of good ideas there. I am skeptical that I can get wrenches on any of those bolts with the engine in place, let alone with the engine super hot. I don't think there is any vertical clearance at all without removing the cabinet. I think I will end up having to cut the corian. The only video i have seen on this topic is the one linked below. He does not show the cutting of the corian or removing of the cabinet, but at least I can see where he cut the corian.

 
Jan 24, 2009
7
Catalina 30 MKIII San Juan Island
Maybe drop the pan a 1/2" and slather the surface with RTV or gasket maker? If there isn't clearance under the engine, maybe mark the height on the engine mount screws, raise it up, take care of the work and then lower it back down?

I've looked at this absurdly large and presumably delicate piece of corian multiple times wondering the same thing. The best ideas I've come up with are an oscillating tool to break the epoxy holding it to the counter top. You can also cut the counter top at an appropriate spot You can add a T shaped transitional piece to hide the gap or fill it in with your favorite caulk or epoxy during re-installation
I found the video below to be the only one I could find where the corian was cut. He does not show the cutting of the corian or the removal of the cabinet (would have been handy to know where the screws are), but you can see where he cut it. The good news is, once cut, you can have the same very good access as the older boats. I have seen several people say the cabinet removal was a 30 minute job on the older boats. I think a t-shaped transitional piece (maybe a nice varnished piece of wood) is a great idea. I think keeping the corian in two pieces is the way to go...

 
Jan 4, 2006
7,817
Hunter 310 West Vancouver, B.C.
let alone with the engine super hot.
Wear long sleeves and have a volunteer wrap your wrench arm with layers of Saran Wrap to stop any hot oil from penetrating your sleeve. Also wouldn't hurt to have a deep bucket filled with ice cold water nearby.

I'd go to any lengths to avoid the destruction work this might entail.

Best of luck. I can really feel for you on this one.
 
Sep 24, 2018
4,752
Catalina 30 MKIII Chicago
I found the video below to be the only one I could find where the corian was cut. He does not show the cutting of the corian or the removal of the cabinet (would have been handy to know where the screws are), but you can see where he cut it. The good news is, once cut, you can have the same very good access as the older boats. I have seen several people say the cabinet removal was a 30 minute job on the older boats. I think a t-shaped transitional piece (maybe a nice varnished piece of wood) is a great idea. I think keeping the corian in two pieces is the way to go...

Unless you have a 3D printer that can account for the lip at the edge of the counter, I think a super thin bead of caulk might be the way to go. The gap would likely be the kerf of the blade. You can also find tan/sand colored caulk. I'm sure there's ways to color match it yourself as well. I saw a carpenter color match polyester resin to the corian. He said he'd been using this method for years and so log as he roughed up the surface with a grinder, it always adhered.

I'd probably use an oscillating tool with the largest metal circular cutting blade I could find. Tiny kerf and fairly easy to avoid cutting cabinetry below. I recently used this to cut some sheet metal and was surprised at how straight of a cut I could make

To free the countertop from the cabinets I'd use an oscillating tool with a flexible straight blade. A circular blade might also work. Either way, it doesn't look like a fun job.
 
Jan 11, 2014
14,211
Sabre 362 113 Fair Haven, NY
I found the video below to be the only one I could find where the corian was cut. He does not show the cutting of the corian or the removal of the cabinet (would have been handy to know where the screws are), but you can see where he cut it. The good news is, once cut, you can have the same very good access as the older boats. I have seen several people say the cabinet removal was a 30 minute job on the older boats. I think a t-shaped transitional piece (maybe a nice varnished piece of wood) is a great idea. I think keeping the corian in two pieces is the way to go...

Corian can be repaired. Search for repairing cracked Corian. The cut made to remove the Corian is the same as a crack.