Prop Shaft Alignment Yearly Maintenance Item

[deafgoose]

Exactly. How much would it have to be off before we would notice?

I hit rocks and totally destroyed my stock prop and there were chunks missing from the blades. I also hit a log last year and one blade was significantly bent.

With a brand new prop, my boat feels so smooth and my shaft was never inspected for alignment.

[cab13367]

Al had you noticed any vibration before checking the alignment?
Just wondering how much it needs to be out before a fella would notice...

No vibrations, but I saw an older post by Brian Raymond of SC and he said that one consequence of an out of alignment shaft is a leaky shaft packing gland because the shaft is spinning in an oval pattern and my boat always has had a leaky packing gland. I changed the packing rope at the start of last summer and it didn't take long for it to start leaking again and would not stop no matter how much I tightened the nut.

[deafgoose]

Interesting.

My shaft seal must be good because I keep my boat in the water at the marina all season and my automatic bilge never turns on.

[DOCDRS]

I checked the gap a little more closely and it looks like I have about .014" at 3 o'clock and zero at 9 o'clock - the couplers appear to be touching at the 9 o'clock position. At the 3 o'clock position, I can insert the feeler gauge about 3/4" snd then it hits something solid. Also, when I run my fingers around perimeter of both couplers, they are perfectly aligned which I think is because they somehow marry up to each other, which explains why I can only insert the feeler gauge about 3/4" - is this correct?

So I would appreciate if those that have done this could give me some advise as to how to get the gap consistent between the two couplers. Do I loosen all the trunnion pins? Or just the rear if I am going to move the rear of the engine?

Thanks,

Al

Good to hear guys doing this. Al you just have to loosen the rear trunnions, both of them. .014 is huge imo. loosem the 2 pins on either side then using a crowbar on the metal motor mount apply pressure in the direction you want to move the motor, this is the trickiest part getting the crowbar in the right place,( in your vdrive to close a ports side gap you are correct in moving the back of the motor to the starboard side)as you apply pressure hit/tap the trunnion/mount with a hammer/5lb hammer sledge, to help vibrate the motor to mount loose(very helpful). You should get a .002 gauge as this is what you will want to get the tolerance to. It definitely helps to have 2 people doing this one checking and one moving the back of the engine....it just goes quicker. Let me know how ya make out.

[DOCDRS]

Brad/Doc,


My question has to do with the trunion pins. I don't know how these pins work so once I loosen the nuts on them, do I tap them toward the back of the boat or towards the front? Put another way, do I tap the threaded side or the non threaded side?

Tap the threaded side(bolt on the end so you don't frig the threads to the back of the boat,)

.

Also, if I decide to move the back of the engine towards the port side (which is what I think I'll do), I obviously have to loosen the trunnion pins on both rear engine mounts. But do I need to loosen the front ones also? I'm thinking I shouldn't but I'm not sure.

No don't have to loosen front

.

Also, what will happen if I continue to leave it as it is? It's been like this for 4 seasons now and to my knowledge, it's not causing any issues.

I guess my answer is why would you not want to have a properly aligned engine to propshaft when you can and are supposed to? Less vibrations on your vdrive, tranny , motor, cutlass bearings,boat. imo And the real speed guys are big on this.

Thanks for this procedure - I would never have undertaken this without it.

Al

[cab13367]

Thanks Doc, I'll give it a shot. And after reading some of Brian Raymond's posts about why it's important, I definitely want this to be right. For one thing, it explains why my shaft seal has always been leaky even after I changed out the packing rope last summer.

[deafgoose]

Thanks Doc, I'll give it a shot. And after reading some of Brian Raymond's posts about why it's important, I definitely want this to be right. For one thing, it explains why my shaft seal has always been leaky even after I changed out the packing rope last summer.

Does your boat have a drip-less seal?

[cab13367]

Does your boat have a drip-less seal?

No, it does not. I think the dripless seals came out in 2007 on the Moombas.

[rdlangston13]

Thanks Doc, I'll give it a shot. And after reading some of Brian Raymond's posts about why it's important, I definitely want this to be right. For one thing, it explains why my shaft seal has always been leaky even after I changed out the packing rope last summer.

how leaky is leaky on a non dripless shaft seal?

[cab13367]

Well, I think I may have to throw in the towel on this one and take it to the dealer to do. I cannot get the engine to budge. I loosened all 4 trunnion pins on the rear engine mount. I cannot get a pry bar in there to get any sort of leverage so I have been beating on the side of the engine (at the motor mount) with a block of wood and a sledgehammer. It has not moved at all.

Any ideas for those that have done this? I have not loosened the pins on the front engine mounts, per doc's advise. I might try that next.

Al