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280 volvo penta outdrive, changed lower leg, now have spacer question

Rmitch

New member
Ricardo,

I originally posted this problem on the Bayliner forum and tonight I saw you had left a message, sorry to get back to you late. I read your post on BOC about there being only two spacers and since I had a long spacer from the 280 leg I removed, I ordered a short spacer, but it still was too long, the rear of the prop stood off the zinc ring more than 1/4". After getting little response from the BOC, I cut down the short spacer from the forward side (zinc side) .220 and it now looks like it fits much better, with only about 1/8 gap. This gives fuller spline engagement and I feel better about the prop nut having more thread engagement.

This outboard leg was changed because of a gearing issue with the 4 cyl Isuzu. I think you were a part of the solution in the fall when I discovered the issue and could not "pitch" my way out of the underprop. I ordered a leg online, was told it was a 280 leg, it is marked with 1.89 and should help solve the problem. This new leg showed bearing race issues and with the shimming involved, I took it 200 miles to Great Falls to a Volvo shop and they replaced the bearings, filled it with lube, pressure checked it and called me to come get it with the caution that "you are going to have to do something about the spacer" It then quickly became winter here in Montana and I winterized and put it out of my mind. I am concerned that the shaft does not seem to fit either of your pictures, it does have a threaded hole in the end and everything except shaft length seems to be right, there is some slack in the splines, not bad, but there and when I tighten up the prop nut it snugs up well with no slack.

I copied the picture of the shaft with a ruler next to it. Is this shaft length something to worry about?

Robert
 

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Do you know the part numbers you have? According to volvo penta propellor guide the 280 takes part number 839423 for both short and long hub props. There are actually 4 different linecutters go to volvo penta propellor guide the key is to properly ID the lower gearbox. Compare the different linecutters i have the SP-A and it also has the short spacer and the prop is inside the sacrificial anode.
 
Good morning Robert!

Ricardo,

I originally posted this problem on the Bayliner forum and tonight I saw you had left a message, sorry to get back to you late.
I'm glad that you saw it.

I read your post on BOC about there being only two spacers and since I had a long spacer from the 280 leg I removed,
A 280 propeller shaft requires the long spacer/line cutter regardless of which prop (long hub/short hub) is being used.

I ordered a short spacer, but it still was too long, the rear of the prop stood off the zinc ring more than 1/4". After getting little response from the BOC, I cut down the short spacer from the forward side (zinc side) .220 and it now looks like it fits much better, with only about 1/8 gap. This gives fuller spline engagement and I feel better about the prop nut having more thread engagement.
The thread title suggests that you changed lower units, so let's start with which lower unit you now have.


This outboard leg was changed because of a gearing issue with the 4 cyl Isuzu. I think you were a part of the solution in the fall when I discovered the issue and could not "pitch" my way out of the underprop. I ordered a leg online, was told it was a 280 leg, it is marked with 1.89 and should help solve the problem.
I would need to see the lower unit gear case in order to tell which one it is.


This new leg showed bearing race issues and with the shimming involved, I took it 200 miles to Great Falls to a Volvo shop and they replaced the bearings, filled it with lube, pressure checked it and called me to come get it with the caution that "you are going to have to do something about the spacer" It then quickly became winter here in Montana and I winterized and put it out of my mind. I am concerned that the shaft does not seem to fit either of your pictures, it does have a threaded hole in the end and everything except shaft length seems to be right, there is some slack in the splines, not bad, but there and when I tighten up the prop nut it snugs up well with no slack.

I copied the picture of the shaft with a ruler next to it. Is this shaft length something to worry about?
First off....... your spacer is missing the line cutter!

The shaft length, the spacer/line cutter and which spinner to use has been a common misunderstanding for a long long time. I have even seen where Propeller Suppliers have it wrong!
Even though the bare shafts (250, 270, 275 -vs- 280, 285, 290 and so on) are different in over-all length, when the correct spacer/line cutter is installed, the NET amount of splines will be the same!

Also, when a long hub prop is used (will not work on the 250, 270), the AFT-most part of the 2 pc spinner will extend into the area where some may think that the shaft is too short. The shaft is NOT too short...... the AFT part of the spinner extends into this area!



.... we will see 2 prop shaft lengths being used between the 250, 270, 275 and the 280, 285, 290, SP and the C lower gear units.
.... the 250 and 270 prop shafts are NOT internally threaded for use of either the 1 pc or the 2-pc spinner with the center locking bolt.
.... when the correct spacer/line cutter is used, it allows for the correct length of exposed prop shaft splines.
.... whether a long or short hub prop is used, the spinner style (1 pc or 2 pc) takes care of the flush or recessed spline issue.




Robert
 
The prop is a Michigan pr 404, measures 3 1/8 on inside bore. Not sure if this a long hub or short hub.

Hub is marked with VTB and also 1.89, I will try to post photo, been trying all morning. I will review this forums practices for photos, I obviously am doing it wrong.
 
Rick,

Here is a photo of the new (to me) gear leg. It is marked VTB on the hub right above the shaft and marked 1.89 on the hub. The propeller is a Michigan PR 404, measuring 3 1/8 long on the inside hub. I do not know if this is a short hub or long hub.

VP NEW LEG  2- Copy.jpgVP NEW LEG 3.jpgVP NEW LEG 4.jpgVP NEW LEG 5.jpg
 
Robert, that is a 290 or later lower unit. If you had to replace the vertical shaft spline coupler with the long version, it will be a “C” or later unit.
 
Thanks all,

I sent a long coupler and a short coupler to the tech in Great Falls, I got back the short one so I assume he used the long one. So, since this is a 290 lower leg, do I need to know anything about different capacities or usage? Is the one piece prop nut good to go with the thin nylon spacer?

Do I know call this leg a 290 C leg?
 
Robert, please re-read my post #4.


RicardoMarine post #4 said:
The shaft length, the spacer/line cutter and which spinner to use has been a common misunderstanding for a long long time. I have even seen where Propeller Suppliers have it wrong!
Even though the bare shafts (250, 270, 275 -vs- 280, 285, 290 and so on) are different in over-all length, when the correct spacer/line cutter is installed, the NET amount of splines will be the same!

Also, when a long hub prop is used (will not work on the 250, 270), the AFT-most part of the 2 pc spinner will extend into the area where some may think that the shaft is too short. The shaft is NOT too short...... the AFT part of the spinner extends into this area!



.... we will see 2 prop shaft lengths being used between the 250, 270, 275 and the 280, 285, 290, SP and the C lower gear units.
.... the 250 and 270 prop shafts are NOT internally threaded for use of either the 1 pc or the 2-pc spinner with the center locking bolt.
.... when the correct spacer/line cutter is used, it allows for the correct length of exposed prop shaft splines.
.... whether a long or short hub prop is used, the spinner style (1 pc or 2 pc) takes care of the flush or recessed spline issue.



Thanks all,

I sent a long coupler and a short coupler to the tech in Great Falls, I got back the short one so I assume he used the long one.
OK..... the long vertical shaft spline coupler is required for any C or later AQ series lower gear unit. Since he returned the short coupler, do you believe that it's safe to assume that he used the long coupler? If so, the lower is a C or later.

So, since this is a 290 lower leg,
If will NOT be a 290 if the above is correct!

do I need to know anything about different capacities or usage?
No! The reduction of 1.89:1 is all you need...... and is only good if your engine calls for this reduction.

Is the one piece prop nut good to go with the thin nylon spacer?
OK..... this is where most have trouble understanding the shafts and spacer/line cutter.
The 250, 270 and 275 prop shafts require the short spacer/line cutter...... it does not matter which prop hub length is being used.
When the short spacer/line cutter is used, X amount of shaft/splines are exposed.

The 280,285,290,SP, and later all require the long spacer/line cutter..... it does not matter which prop hub length is being used.
When the long spacer/line cutter is used, that same X amount of shaft/splines are exposed.

If you are using a long hub prop, then you must also use the AFT-most section only of the 2 pc spinner along with the center locking bolt.
If you are using a short hub prop, then you must use either the 1 pc spinner, or both sections of the 2 pc spinner, along with the center locking bolt.



Again...... use the short spacer/line cutter for the 250, 270 and 275 prop shafts, and the long spacer/line cutter for the 280,285,290,SP, and later prop shafts.

Do I now call this leg a 290 C leg?
NO...... the 290 is a 290...., the SP is an SP....., the C is a C......, and so on.
 
This may help you with the spacer/line cutter and exposed shaft/spline length, etc.


250, 270 and 275 shaft
The 275 shaft will be internally threaded for the keeper bolt.
Also, the 275 exhaust outlet has been moved AFT so that a long hub propeller can be used.

Prop shaft 250 thru 275   dimensions.jpg


280, 285, 290, SP and later


Prop shaft 280 thru SP  dimensions.jpg


Prop shaft lengths explained.jpg
Prop shaft lengths explained 2 .jpg
Prop shaft lengths explained 3 .jpg





This last image (below) does not pertain to your question. I posted it by mistake.
 

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Rick,

First of all thanks for all your help, not only in finding this gear leg on line but with your patience in dealing with this problem. I am confident that what we now have will work.

To finish the subject, I have attached two photos of the prop shaft with the line cutter and the prop nut installed. I also measured the shaft length from the shoulder (without spacer) to the end of the prop shaft threaded end and it was 4 1/2 inches, which does not match the pictures you kindly attached. And, when I cut down the spacer, I ended up with the "X" dimension of 3 inches from the spacer to the hub nut with the hub nut screwed all the way in. The inside of the prop hub is 3 1/8, so all is well.

I did like your picture of the prop nut with the safety wire.

VP PROP SHAFT 1.jpgVP PROP SHAFT 2.jpg
 
I would like to see the AFT end of the prop while installed ..... minus the spinner.

If the splined shaft is fairly flush with the prop hub splines, then you can use a full spinner along with the locking bolt..... or both parts of the 2 pc spinner along with the locking bolt.

If the splined shaft is recessed within the prop hub splines, then you would use the AFT-most portion of the 2 pc spinner ONLY, along with the locking bolt.
 
Rick,

Here is the photo of the end of the splines with the prop attached. The spline is slightly recessed. The prop nut with a the thin nylon spacer fits well.

VP Prop shaft end 1.jpg
 
Rick,here are a couple of photos of the side view, I did clean up gouges and scratches on the lower leg and painted it black. VP PROP SIDE 3.jpgVP PROP SIDE 1.jpgVP PROP SIDE 2.jpg
 
The prop fit looks to be ok. I wasn't sure about the AFT end.

Also, I couldn’t help but notice that the ring anode has been painted.
Sacrificial anodes cannot be painted! The material must be able to expose itself to the water.
If this boat will be moored (even if for a short duration), you will want to replace the ring anode.

There will be a second sacrificial anode attached to the lower area of the transom shield.
That anode cannot be painted either!



.
 
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Good catch, I know better. I need to get another anode and another locking bolt, the existing bolt allen head is rounded off and difficult to tighten. Thanks.
 
The OEM keeper bolt will have a nylon insert in it that creates restlstance against backing out. The hole for the nylon insert weakens the bolt.
If the threads were to become corroded, this bolt can break at this location.

I would replace it with a non-OEM same length and grade SS 5/16” NC cap screw.


.
 
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