Hunter 34 engine alignment

RoyS · Dec 7, 2021

Usually, you just remove the four bolts that join the two halves of the coupling and slide the propeller shaft with that half of the coupling slightly back toward the prop. Everything moves back, prop shaft and coupling half. Then you insert feeler gauges between the coupling halves and try to achieve equal spacing within, say, a few thousands of an inch by adjusting the motor mounts. However, you must maintain the prop shaft centered in the stern tube. That may be difficult while in the water. I always looked at that alignment from outside the hull while on stands. Hope I understood your question.

dmax · Dec 7, 2021

If the shaft is hitting the log, you need to center the shaft in the log first as Roy says - this is a potentially dangerous situation where the log can be damaged and water will enter. Most likely that shaft is too low from the motor mounts compressing over the years. Tough to do in the water but I'm sure there's a way to get it reasonably centered. This may work: cut a 1 - 2 foot piece of PVC pipe whose I.D. is larger than the log/stuffing box in half lengthwise (actually, better to do it 60/40 and use the 60). Place it over the log with any spacers/clamps necessary so the PVC pipe is centered and parallel to the log. Now see is the shaft is centered within the PVC pipe. A doughnut over the shaft the dimaeter of the I.D. of the PVC pipe would help with centering. There may be other methods, be imaginative - you don't want the shaft thumping against the hull.

markwbird · Dec 7, 2021

You actually want to do any final shaft alignment with the boat in the water. The hull shape will change when the boat is on stands due to being supported differently than it is in the water and this can affect the alignment.

Tally Ho · Dec 7, 2021

Do you have a zinc or something on the shaft that is hitting the strut or something else that keeps the shaft from sliding back away from the transmission?

I just removed my coupling and stuffing box to install a dripless seal, and as I was trying to work the shaft back out of the boat…it hit something. Went outside (boat on the hard) and found the stern-most shaft zinc was pushed up against the strut. Had to re o e it to slide the shaft back far enough to get the stuffing box off.

Or maybe I am not understanding the issue you are facing.

Greg

Mike Oldak · Dec 7, 2021

i had a marine mechanic help me align the engine on my H34 3gmf. I replaced the motor mounts (after 35 years) and had to reinstall the angle irons. I drilled out the mounting holes then inserted thickened epoxy and redrilled for the bolts. Then with the engine in place we added some shims under the engine mounts to get the engine at the right height and angle. We used a cell phone level app that we placed on the engine and also on the drive shaft to make sure they would be in alignment. Then pushed them together and bolted them up.

Mike

Tally Ho · Dec 13, 2021

Luna Blue said:
The shaft is clean and no zinc installed. As I stated, the boat is in the water and ready to align. My problem is the coupling. I need the coupling to slide back to be able to align. We should all understand that you don't do this on the hard. I was hoping to find some feed back here. We would like to get underway for the south. There's no service at this marina and others in the area are 6-8 month waiting list. Has anyone been successful with sliding the spit shaft coupling back towards the dripless and aligned the engine PLEASE?

I am not sure I understand what the issue is exactly…

1) do you have a split coupling? We’re you able to open it? Did you remove any set screws in the coupling that contact the shaft?
2) is the coupling bolted to the transmission output flange?
3) what sort of shaft seal do you have (traditional stuffing box, Volvo Penta dripless, PSS )?

Why are you trying to slide the coupling back? Do you mean you want to slide the whole shaft assembly (including the coupling) back away from the transmission output flange?

do you have a photo of the shaft/coupling arrangement as it is now? Maybe that would help us figure out how to help you.

When I replaced my shaft and coupling, I did a rough adjustment on the hard to get the shaft pretty well centered in the shaft log. Then some fine-tuning once the boat was in the water.

Greg

Tally Ho · Dec 14, 2021

Luna Blue said:
As stated prior, slip shaft coupling, PSS dripless. Yes, I have removed bolts between coupling. Removed set screw. If you have in fact done this then you know the shaft needs to be centered. Keep in mind aligning engine to shaft. Prior post in thread explains the details. Are you a Hunter owner? Have you personally done this with success? Original post... I need information as per my original post.

I used to own a Hunter, but your same boat. Now I have an O’Day 322, but they all have shafts, couplings and engines (unless you have a sail drive). So, just trying to offer some help…if you only want to hear from owners of Hunter 34’s, just say so.

No one seems to have an answer for you, probably because we can’t see what the issue is from your description...so I am trying to ask some probing questions to see what comes to light…

I have successfully changed my prop shaft, stuffing box, coupling and aligned it all so it doesn’t hit the shaft log.

Just put the coupling back on today, and bolted to the transmission.

Just trying to help.

Greg

MikeHoncho · Dec 15, 2021

Luna Blue said:
As stated prior, slip shaft coupling, PSS dripless. Yes, I have removed bolts between coupling. Removed set screw. If you have in fact done this then you know the shaft needs to be centered. Keep in mind aligning engine to shaft. Prior post in thread explains the details. Are you a Hunter owner? Have you personally done this with success? Original post... I need information as per my original post.

Take it easy partner….these people are trying to help you with what your are asking. You keep saying your trying to slide the coupler back. Do you mean the coupler itself back on the shaft and relocate it on the shaft or do you mean the whole assembly back? Your question is confusing……normally the whole assembly gets slid back, you do the work then you slide it all back to the mating coupling and align with feeler gauges between the two couplings. Help us help you.

MikeHoncho · Dec 15, 2021

So you are trying to align the shaft itself to the engine’s coupler without using the split coupler that is on the shaft? If so that is a new one for me.

MikeHoncho · Dec 15, 2021

Loosen up the collars on the drip less to allow movement, align the engine to the shaft using the couplers not the shaft itself, bolt them together the. Reset the dripless. Centering using the shaft itself makes little sense to me when you will change it while adjusting alignment with feeler gauges, then fix again after you slide the coupling back forward.

MikeHoncho · Dec 15, 2021

Luna Blue said:
The dripless gland is pushing shaft and coupling to the engine. Please try and picture this. Try to use the feeler gauge doesn't work like this because the coupling is making contact making the process rather impossible. Not correct.

Ok that’s making sense now. With my dripless I could loosen the shaft collar that loaded the matting surfaces. This would allow me to slide the shaft like your needing to do so the couplers aren’t forced together to get a accurate feeler gauge reading. Then when all done reload the seal. That’s all I got.

MikeHoncho · Dec 15, 2021

Luna Blue said:
Please try and picture this.

I think 5 people have been trying to picture this over what? 19 posts!