how hard is it to replace an A4 (with an A4 rebuilt)?

[steven]

Is removal of the engine possible with the boat in the water ?

Here is a pic. Where do you decouple ?

thanks all for advice, this is really new to me.

 

[Loren Beach]

Is removal of the engine possible with the boat in the water ?

I have not done this with any other boat, but it was relatively easy for *us to remove the old M25XP, and drop in the new Betamarine25, while at our slip. See my blog for some pix.
The main halyard was used, with the cabin top Lewmar 30 doing the work. I have since upgraded the housetop winches to size 40, and wish I had done so years sooner.

*Full disclosure: I was working with/along side an experienced ship wright. He had done many engine swaps before.

 

[steven]

Here is a pic. Where do you decouple ?
thanks all for advice, this is really new to me.

 

[Dave G.]

At the coupler. Should be 4 bolts holding it to the transmission.

 

[tenders]

Look at your black grounding wire in the photo above. The set screw brushing the wire on the left side of the picture is screwed into the coupling, perpendicular to the shaft. That presses a rectangular piece called a Woodruff key into the shaft and also locks the shaft to the coupling. If you are going to remove the shaft from the boat, or remove the coupling from the shaft, the set screw will need to be loosened - you might as well remove the set screw. If by some miracle you do not need to do this, the set screw does not need to be disturbed. You probably can’t remove the shaft from the coupling just by releasing the set screw and pulling out the shaft.

The other bolt touching the ground wire in the photo is one of probably four shaft coupling bolts that need to be removed. They screw directly into a threaded piece called the engine coupling, which doesn’t need to be disturbed. Once those bolts are out, nothing is holding the shaft to the engine except - possibly! - rust.

If you’re disassembling all this you may decide you want to refurbish the shaft packing gland, maybe replace the shaft itself, etc. (note, shafts are not that expensive.) This will require removing the shaft from the coupler, using whatever home-grown press device you can maneuver in place. Lots of discussion on how to do that at the moyermarine.com forums. Your boat seems to have pretty clear access to the coupling, which is good. My boat is a vee drive, and does not. Squeezing the coupling off the shaft in those conditions is probably the single worst job I’ve had to do on the boat.

 

[frick]

When I pulled my A4 Out of the E29 in 2002, The cost of the rebuild was exactly half the price of a new yanmar diesel. That same yanmar is still purring perfectly today. It was a GREAT Choice

 

[Joliba]

In 1976, while cruising in our Cal 2-30, we needed to pull our A4 out twice during the same year for repairs. The first time we were at a dock in Cozumel and carried the engine ashore on a gangplank. (See photos below.) The second time we had no outside assistance and were at a slightly rolling anchorage at San Cristobal island, in the Galapagos. There, we brought the engine back to the boat from shore in a small leaky wooden rowboat that I found abandoned on the shore. All transfers were accomplished using the boom with multiple halyards spaced to accommodate the stresses. We used a block and tackle (boom vang) to lift. We were 3 young totally inexperienced guys.... yet it was quite successful and not really too difficult. Or, perhaps, we didn't know enough to be worried. (The whole story is documented in my book.)

 

[Prairie Schooner]

@steven - It was nice to speak with you at the recent EYo video meeting, Steven. In a conversation with some friends yesterday they described changing from a dripless seal back to a stuffing box, while the boat was in the water. Their neat trick that might be of help to you is this: One of them dove on the boat and jammed plumbers epoxy putty around the shaft at its entrance into the log. This was temporary, but enough to prevent major leaking and keep the shaft located. You could even embed some wire loops in the plug to make it easier to pull out. FWIW

 

[Kenneth K]

One of them dove on the boat and jammed plumbers epoxy putty

Perhaps you mean plumber's putty, not epoxy? Epoxy might be hard to remove.

 

[Prairie Schooner]

Perhaps you mean plumber's putty, not epoxy? Epoxy might be hard to remove.

The stuff I've used was an epoxy putty. There are different brands, however. Might be other formulations.

 

[JP in Sandusky]

Or, perhaps, we didn't know enough to be worried. (The whole story is documented in my book.)View attachment 53520

I've done a few things with bigger old tractors. I've even heard guys talk through the pros and cons of "repairing" their own steam boilers. (I mean if you can weld a mower deck, why not try your hand at welding a steam shovel boiler.... )

I've never, though, seen anyone carry an engine or transmission barefoot! (Well, maybe....I did have a cousin that repaired 2-cycle engines, and he was regularly only wearing short-shorts and a grin.)