Engine Mount Status

[rnummi]

Could someone take a gander at these and comment on condition? Replace the rubber? W/ what? Leave them be for awhile?

[Beta Don]

There is no flex *at all* in the stuffing box on 4D61 powered A27's, so the prop shaft cannot move at all in any direction. This means the engine/trans cannot move at all, so rubber engine mounts are not an option - I ran into this problem when repowering mine. Yanmars come with very cushy, soft, noise and vibration absorbing rubber engine mounts, but because of the Albin's rigid stuffing box, I could not use them

If you're keeping your 4D61 and the lag screws are tight (meaning your engine beds are not rotted) I would definitely leave well enough alone and not touch the engine mounts - You have enough real problems on your hands already without opening up that can of worms!

Don

[Vic K]

FYI:

I had two different mechanics look at the mounts that were under my 4d61 that look like yours and both said they were shot. What to replace them with was the problem. First of all I had a flex coupler installed between the shaft and tranny, the engine mounts ( this is the second set of mounts) I ended up with came from a new Beta. Now there's very little or no engine vibration that's noticeable. Also the noise level is low enough at cruise rpm that you can carry on a conversation, hear the VHF and even play the stereo. I'm not saying is quiet but it's a heck of a lot better than before. Certainly don't need ear plugs or muffs.

If your still going over your boat make sure to look at the hull to deck connections. That may have the same level of surprise as the pilot house cabin connections.

Vic

[JT48348]

Could someone take a gander at these and comment on condition?

Man that looks bad. Very very bad.

[Sprig1]

Hi Vic do you know what flex coupler you have. I might as well put it on the list. Thanks Chris

[Vic K]

Chris,

I'm pretty sure it was by 'R&D'. There are different configurations for different engines and mounting hole arrangements. I believe a 4 X 4 (square and holes) fit mine. You can talk with their people.

Vic

[rnummi]

Can they be DIY or is it a yard job?

[Vic K]

The mounts were installed on my boat in the slip by a mechanic. I'm sure if you know what you're doing and have the equipment you could DIY. The alignment it self takes some knowledge. I think three out of the four bolts that held the old mounts had to be cut. These were not lags but bolts that fasten to nuts bedded in the engine beds. The holes for the new mounts were in a different position. Where possible the old holes were filled with epoxy.
Like Don mentioned you have to be sure the bed is solid.
Attached is a photo of the 'harmonic balance' (someone had to tell me what it was) that was connected to the old shaft. This along with the rubber in the mounts were put there for a reason.
Good luck,

Vic

[Beta Don]

Mine had that same enormous 'flex coupling' if indeed that's what it is

My old engine mounts had huge lag screws into the engine beds - 5/8ths by 3 inches I would guess. It looks from the photos that yours are the same. When I removed them, the beds were sound so I just filled the holes with epoxy and drilled new ones for my new engine mounts

Maybe my mounts were the same as yours - Not sure. I do know that there was a good bit of wear on my bronze shaft where the it came though the stuffing box, so either my engine was misaligned or the engine mounts were shot or defective. There was only 1100 hours on the old engine when I removed it

You can DIY the engine alignment, *if* you understand the principle of what's happening. You pretend that the flange on the prop shaft is a 'fixed' object and only the engine/trans is moved port or starboard and/or up or down so that the transmission flange aligns perfectly with the coupling flange on the prop shaft - This assumes the shaft is where it needs to be . . . . centered in the stuffing box. When you get the transmission end close to where it needs to be, you'll see that the front end of the engine will need to be moved to get the flanges flush with each other. You use a feeler gauge when you get close so you can tell if the two flanges are perfectly mated. When the two flanges touch, inserting the feeler gauge will show you where the 'crack' is widest and that will tell you what you need to move on the mounts to get the flanges to fit absolutely flush together, where the smallest feeler gauge will not fit anywhere between the flanges - Only then do you put any bolts in to hold the flanges together. If it's your first try at this, it may take all day - Once you've done a few, it goes much faster because you have a better understanding of what need to be moved, how much, and in what direction. Anyway, when you get it to where the two flanges come together and there is no room for the smallest feeler gauge anywhere around the flanges, you can rest assured the engine is properly aligned

Don

[rnummi]

Thanks guys....looks like a yard job... . My inventory of things to do keeps getting longer. Good info though. i need to get her off the trailer and 4 miles down the street to a lift.