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hit a rock or log and damaged prop-anything other damage I should or can check for?

C

cybrdweeb

Member
Took the boat out for the first time since changing a leaking shift shaft seal and all was great until coming in to the dock and struck something hard under the water. Luckily I was going very slow and shut down right away and floated away from the impact. I looked at the prop in the water and could see it was damaged but no blades missing so I fired it up and drove off slow and did notice a slight vibration. Got on shore and the prop has a couple small pieces missing and one slightly bent edge on a blade and lots of seaweed tangled.

I already sent the prop out to be repaired but I'm worried about concealed damage.

My questions are:

1. Will just a small amount of damage to the prop cause a vibration?

2. Is there anything that protects the outdrive (SP C drive) and motor from impact damage such as a shear pin or something similar? (Nothing is broke because it shifts and drives- just wondering)

3. I ran it on the muffs when I got home and looks like there might be a very slight wobble looking at the prop cone- I assume this mean bent prop shaft. I'm posting a couple videos and maybe someone can tell me if it looks ok or not.

thanks

[video]http://s151.photobucket.com/user/cybrdweeb/media/Wellcraft%20Excel/M4H06360_zpsdb3cae12.mp4.html[/video]

[video]http://s151.photobucket.com/user/cybrdweeb/media/Wellcraft%20Excel/M4H06361_zps6f1f190c.mp4.html[/video]
 
To answer your questions:

1) Yes, a small amount of damage to your prop can cause vibration.
2) Yes. There is a splined sleeve designed to shear in case of major impact. It is located between the upper and lower units.
3) Not necessarily, you will need a dial gauge to ascertain that the shaft is bent. The wobble maybe just caused by the prop hub or a bent blade.

I think you have already noticed that the skeg is broken.
 
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Good eye on the skeg- actually it was ground down by the previous owner who forgot to raise the outdrive all the way before trailering. Had the skeg been proper length I may have saved the prop.
 
I agree with Eduardo.

Pull the propeller, and place a dial indicator on the shaft. Turn the shaft and see if there's any "run-out".
The OEM service manual will give you an acceptible run-out range..... and it isn't much.

Good news is, this prop shaft can be removed, straightened (if not bent badly), and re-installed with ZERO change to any shim values and/or bearing pre-load changes.
Don't let anyone tell you otherwise!


.
 
I did a "backyard mechanic" check of the shaft last night- I took a Sharpie marker and and visegrips and clamped the tip of the marker very close to the shaft and spun it and watched for ink marks on the shaft indicating a high spot. No obvious bend so I then moved the tip to touch the shaft and spun it and watched the ink trail- it was thicker on one side by a little so it may have a slight bend. I'll have to get a dial indicator to check for sure but at least at this point it does'nt look too bad.
 
Now I'm confused about the prop- the one that is on it is a VP part # 854979 which according to the website is a "long hub". I see a long hub is supposed to be held on by just a nose cone and no spacer. Mine currently has a cone and a spacer so do I have the wrong prop or the wrong cone setup? Outdrive is 1992 SP-C.
 
Don't feel alone.... this stumps many AQ series Volvo Penta owners.

Look at the link that Eduardo posted.

NOTE: There is an error in the language of that information.
The verbiage reads; "Standard Hub installation" and "Long Hub installation", and they're showing "A" as being two different spacer lengths.
The prop shaft length determines which spacer/line cutter is used (short .625" -vs- long 1.30") ..... not the propeller hub length.

I.E.
200, 250, 270 and 275 are what we'd consider to be "short shafts", and all require the short spacer/line cutter in order to net the correct prop shaft length.


280, 285, 290, SP etc, are all what we'd consider to be "long shafts", and all require the long spacer/line cutter in order to net the correct prop shaft length.


IOW, it's somewhat of a misnomer to call out short shaft/long shaft, when in reality either prop shaft will net the exact same length when the correct spacer/line cutter is used.

If we were to swap a correct long spacer/line cutter for an incorrect short spacer/line cutter, the prop hub will now interfere with the ring anode and bearing carrier.

Just a heads up on that!



"A" is the prop shaft spacer/line cutter and will be the long one for your SP drive.
This part remains the same for either propeller hub length.
DO NOT change this part!

"C" and "D" represents the 2 pc spinner..... which when used together, these net the same over-all spinner length as the 1 pc spinner.

"C" and "D" (w/ the center keeper bolt "E") are both required for the short hub propeller.
"F" is optional when "E" is used.

D" only (w/ the center keeper bolt "E") is used with the long hub propeller, but only for a prop shaft that is internally threaded.


Nothing else changes.



.
 
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DSC06365.jpgWell it gets even more confusing after measuring my shaft - it does'nt match either the long or short shaft dimensions. Am I measuring correctly?

DSC06362.jpg
 
You are over-thinking this.
The SP C lower unit is very similar to the 290. These are still in the AQ series family.

Just use the space/line cutter that came on the drive originally (assuming that is was correct to begin with).
If the short spacer is used, the propeller will make contact with the ring anode.

The 2 pc spinner will allow you to use either the short of long hub propellers.

BTW, your SP-C drive will look like this drive.
Your hydraulic cylinders will connect directly to the main suspension fork.
Your lower unit exhaust outlet housing will also look like this one, and will have the back-flow prevention flapper on it.





Here's what a 275 lower unit looks like.




Your SP-C lower unit ring anode will look like this.




This is a ring anode for the 250/270/275 lower units.




.
 
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Thanks Rick- I seem to overanalyze everything. I should have just realized it worked fine before so put it back the way it was- instead I imagined a probelm that didnt exist.

thanks for the reality check!
 
I got my prop back after repairs and went to put it on realized I dont have a spacer (line cutter) or washer for under the cone. Either I never had a spacer or it was stuck in the prop when I sent it out and it didnt come back.

The prop DSC06377.jpgDSC06378.jpgDSC06380.jpgseems to fit fine and spins freely but has very little clearance on the back side. If I need a spacer what size shuold I get- there isnt much of the threads on the shaft sticking out now. Also whats the purpose of the washer under the cone?
 
You are missing the line cutter/spacer! I think the part number for the SP-C is 832082, but you may want to check with your VP dealer.
If you are talking about the nylon washer, I would say that nylon does a better job than metal in preventing the cone from becoming loose once you tighten it and further secure it with the Allen bolt. Not sure if it may also be there to prevent electrolysis/fretting between the prop and the cone as well, but whatever its mission I would leave it where it is.
 
I may have been mistaken earlier.

It's possible that somewhere during the time when the C and later single prop drives came out, the earlier spacer/line cutter was no longer being used.


Let me go back to this image.
The propeller looks to be too close to the ring anode and bearing carrier here.

attachment.php


And this small recessed area (in the prop hub) I believe is missing a ring spacer.

attachment.php





I made up a drawing with some notes here.

The blue line here shows a shoulder location that does not exist on the pre-C drive prop shafts.
Instead, this shoulder is further forward, so the typical spacer/line cutter stops further forward on this shoulder.

The end result still places the propeller in the same location... and the long hub prop/short hub prop "spinner" suggestions would still apply.
 

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I ordered a line cutter and nylon washer yesterday before your post- looks like I need to look for a ring spacer for the prop now. I guess I'll see what fits and what doesnt when I get all the parts

thanks again for all the help- much appreciated!
 
cybrdweeb said:
I ordered a line cutter and nylon washer yesterday before your post- looks like I need to look for a ring spacer for the prop now. I guess I'll see what fits and what doesnt when I get all the parts

thanks again for all the help- much appreciated!
Click to expand...
OK.... now I'm a bit confused here.


If (key word "if") the SP-C prop shaft shoulder is in a different position from the earlier shaft shoulders, then it would look like a ring spacer is required.
This would fit into the small bore of the propeller hub. ... similar to the AFT prop of a Duo Prop set up.

However, if the SP-C prop shaft shoulder is in the identical location as the earlier prop shafts, then the spacer/line cutter (SEQ #37 as per Eduardo) would be required.
This is what I first starting suggesting early on in your thread..... until I saw that shoulder location.


Eduardo.... help me out here! :confused: ............ ;) ......


Look at the difference in the space between the shoulder and the end of shaft (attached image).
Even in this image, they show a greater distance.
 

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Ah, gotch ya.
I was thinking that there was a difference because of that shoulder location.

BTW, there's an SP-A and there's an SP-C and later drive.
As far as I know, the SP-A is similar to the 280/290 prop shafts.
 
Well the saga continues- I got the spacer/line cutter and its a Volvo Penta part and the correct one for my prop (long hub) but the spacer stops at the shoulder way to high on the shaft so the prop doesnt slide down far enough. I did take the boat out without the spacer and it ran great- the prop is very close to the anode but doesn't hit when spinning by hand but appears to be wearing there when running. I need some sort of spacer or a different prop but don't know what to look for.

PROP1.jpgPROP2.jpgPROP3.jpgPROP4.jpg
 

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cybrdweeb said:
Well the saga continues-
  1. I got the spacer/line cutter and its a Volvo Penta part and the correct one for my prop (long hub)

  2. but the spacer stops at the shoulder way to high on the shaft so the prop doesnt slide down far enough.

  3. I did take the boat out without the spacer and it ran great- the prop is very close to the anode but doesn't hit when spinning by hand but appears to be wearing there when running.

  4. I need some sort of spacer or a different prop but don't know what to look for.
Click to expand...


  1. Again, the propeller hub differences should have no role in this. These spacers are specific to the propeller shaft..... not the propeller hub.

  2. Let's talk in terms of Starboard, Port, Foward and Aft.
    IOW, the spacer/line cutter that you bought is resting too far AFT..... correct?
    As I see in your photo, this would clearly be the case.

  3. Do some math here.
    Measure the distance from the bearing carrier to this shaft shoulder, and then measure the corresponding location of the recessed area within the prop hub.
    Compare measurements.

  4. I think that this takes us back to the idea that the SP-C propeller shaft is quite different from the previous model propeller shafts.



Do you recall the round washer like spacer that I posted earlier?

I'm now thinking that you need this style spacer..... of which will not include a line cutter.
If so, perhaps the thickness of this washer/spacer will bring the prop hub further AFT enough to give the clearance that is needed.


Questions:
This prop was sent in for repair... correct?
Is it possible that the spacer remained in the hub, and was lost at the Prop Shop?



Quick story:

I did a drive service on a man's boat which included propeller repair.
This was a SeaRay with Volvo Penta DP drive.
When he picked up the boat, I gave him a thorough shake-down on Duo Prop installation... since I had not installed his propellers (two sets.... and I wasn't sure which set to install).
I showed him exactly where each spacer was to be installed.

Well, he installed the props, but he omitted the FWD propeller spacer.
He ran the boat until he discovered the problem.
The FWD propeller had moved forward and chewed up the prop shaft bearing carrier.

Some $800+ later, he discovered just how important these spacers are.



.
 
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Yes I sent the prop out for repair and it is very possible the washer/spacer did not come back but I'm not sure there ever was one.

I've searched the internet for a replacement spacer but have come up empty- the only VP spacers I find are like the one I already bought that doesnt fit.

I need a beer - my brain hurts
 
I think I got the problem solved- I made a spacer that rests on the shaft shoulder and moves the prop out a good distance. I cut a section off the line cutter spacer I bought and slid it on the shaft.

I still dont know what the proper distance should be between the prop and anode- the skirt of the prop is just a little below the anode ring. I could shorten the distance by grinding the spacer smaller if I have to.

I'll ask the experts- does this like it will work ok?

DSC06430.jpgDSC06431.jpgDSC06433.jpg
 
If this spacer washer cannot slide forward past the shoulder, in theory it should work just fine.

I'm thinking that the thickness of the spacer should match the depth of the recess in the propeller hub.


Does the prop hardware seem to fit OK?

******************************

And once again, let me remind you that your payment is ten days past due. :D




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I think I wll decrease the thickness of the spacer.

Yes the hardware fits good- I am using just the cone without the cone spacer and it snugs up nicely- the center of the cone actually fits inside the prop.
 
The prop clearance with the anode seems just about bang on to me.

The cone center is supposed to fit inside the prop hub. Make sure you also install the nylon washer.

Still scratching my head about the spacer in the line cutter you got, and I'm just wondering if they gave you the correct part. The one in the sketch for the SP-C seems to have a very, very narrow spacer attached to it; max 1/4" is my guess.

Another thing you may want to do is to coat the stainless Allen bolt with Quicksilver Perfect Seal or similar before installing it; it will prevent galvanic reaction with the prop cone and it will help to prevent it from becoming loose once you have tightened it.
 
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