Prop Too Tight?

[chargerboy]

Just finished putting my Alpha 1 lower unit together and on the boat, now installing the propeller, but when I tighten it to 50lbs torque, it pulls the prop shaft so far forward that the gears don't engage in forward or reverse. Back the prop nut off so the prop is slightly loose, and now forward will work but not reverse. Loosen it so the prop is so loose that it wobbles and i get reverse back. What is the cause of this and how do I fix?

 

[Rocky_Road]

Re: Prop Too Tight?

Just finished putting my Alpha 1 lower unit together and on the boat, now installing the propeller, but when I tighten it to 50lbs torque, it pulls the prop shaft so far forward that the gears don't engage in forward or reverse. Back the prop nut off so the prop is slightly loose, and now forward will work but not reverse. Loosen it so the prop is so loose that it wobbles and i get reverse back. What is the cause of this and how do I fix?

Have you got the thrust washer going on before the prop?

 

[chargerboy]

Re: Prop Too Tight?

Yes I do

 

[Don S]

Re: Prop Too Tight?

Just finished putting my Alpha 1 lower unit together

Are you sure you have the lower unit put back together properly????? There is no way tightening the prop can change the shifting.
When you tighten the prop down, can you still turn it?

 

[chargerboy]

Re: Prop Too Tight?

No, I'm not sure that I put the lower unit back together properly. When the prop is tight, I can still turn it freely. I received the lower unit already taken apart, I had to install the bearing carrier assembly, along with the bendable tightening ring and the retainer. I'm pretty sure that's what I've done wrong, but I don't see how bad I could have screwed that up. I pushed the carrier in as far as it would go, and tightened the ring to what felt like the manufacturers spec of 220 pounds of torque. Could it be that it still did not go in far enough? Any ideas of whether or not I should be seeing the threads on the lower unit housing after turning it in? It did not go in far enough to expose any of the threads, and when looking at it through the top down the exhaust run, I could see a part of the retainer that was shiny, as if it could have gone a little further in. Tried, but couldn't get it to go any more.

 

[Don S]

Re: Prop Too Tight?

It takes a lot of special tools to put a drive together correctly. And all the parts have to be in the proper order. Did you check gear heights? Backlash?
Did you even look at a service manual?
IF not, look here
http://forums.iboats.com/showthread.php?t=251571

 

[chargerboy]

Re: Prop Too Tight?

I appreciate the manual Don, so far I've been working off bits and parts of information I've located in random places on the internet. Seeing as I did not replace any parts in the drive, I didn't think I'd be changing any of the measurements inside, the drive was disassembled by somebody else for inspection, and never put back together. I made sure to put everything in the right order (the bearing carrier was already assembled, I just had to re-install it) and put the lock ring and retaining ring back on. Is it still necessary to have all the special tools for this? I thought I could get away without them. I've read in one manual how to check the heights and backlash, but if the drive worked fine before being taken apart, would any of that have changed?

This sounds like it might be over my head, I was hoping for an easy answer, I'm new to working on boats, great with cars, but this is completely different territory. Thanks for taking the time to help, and sorry if i sound like such a newbie.

 

[Don S]

Re: Prop Too Tight?

Did you get all the shims and spacers back in place properly? Are you sure they weren't missing from your pile of parts?

 

[JustJason]

Re: Prop Too Tight?

tightened the ring to what felt like the manufacturers spec of 220 pounds of torque

Torqueing to 220 FT/LBS is not a thing that's done by feel. It takes a hella big torque wrench to do it, plus some muscles, plus a way to secure the drive.

If the inner end of the prop is hitting the retaining ring, and you are positive you have the thrust washer in, then the drive is put together wrong.

 

[chargerboy]

Re: Prop Too Tight?

Did you get all the shims and spacers back in place properly? Are you sure they weren't missing from your pile of parts?

I haven't seen anything in the manuals that suggest any spacers or shims relating to the installation of the entire bearing carrier assembly. All bearings and seals were already installed, I just had to slip the single part inside, tighten the ring, and that was the only work I did on it. I didn't have any leftover parts in the box, and I haven't seen any indication that I missed any spacers or shims.



Jason, you are right, I'll buy a 3/4 inch torque wrench tomorrow and double check. I did muscle it in there pretty tight, but it would be best to see if I can't get it in any further.


Does anybody know of a measurement I could take from the top of the retainer ring to the outer edge of the lower case to get an idea if it's placed correctly?

 

[cr2k]

Re: Prop Too Tight?

And yes there are usually several threads showing when the carrier is in all the way.

 

[chargerboy]

Re: Prop Too Tight?

I looked all over, I can't find any photos that show the correct position of the carrier. Here is a photo of mine, does this look to anybody like it should be in any further?

 

[JustJason]

Re: Prop Too Tight?

The retainer looks alright depth wise, how exactly did you torque it? With just a breaker bar hopeing for the best?

Any chance you can take multiple pix of all your parts? Pix of the prop and all the washers parts and pieces you have.

If you lock the drive in a stand (or hell, just lay it down on a table and have somebody hold it) Grab the propshaft and pull it in out out. How much play do you have? 1/16th of an inch? More, less??

 

[chargerboy]

Re: Prop Too Tight?

Here are the parts i think you mean. I first installed the new propeller, a 19 pitch 13 1/2 inch 4 blade stainless prop made by Signature and noticed the problems, so I reinstalled the old prop that came with the boat to try, and had the same problem.

My torque wrench only read up to 150 lbs, so I maxed that out, and then put a breaker bar on it to turn it what i thought was 50% more effort to get it to the 220 lbs mark. There is 3/8ths of an inch play in the shaft with the prop off and the gear in neutral, although when the gear is in forward it tightens it up so there's no play, pulling on the shaft will put it back in neutral if it's not connected to the upper unit linkage.

I apologize for the size, I uploaded these from a different site as this one wouldn't let me upload any more photos.


http://img266.imageshack.us/img266/2509/002gzb.jpg
http://img12.imageshack.us/img12/2479/003vd.jpg
http://img202.imageshack.us/img202/8158/004lpo.jpg
http://img38.imageshack.us/img38/2411/005iqkg.jpg

 

[Bob_VT]

Re: Prop Too Tight?

PLEASE DO NOT load anymore photos until you have read and followed the directions found here http://forums.iboats.com/showthread.php?t=285637

Our max size is 640 x 480

 

[achris]

Re: Prop Too Tight?

When the prop is tightened down, can you rotate the shift shaft or is that locked up? Does the prop push up against the edge of the gear housing? Can you turn the prop easily or is it stiff?

Also, when you put the bearing carrier in, with reverse gear and its bearing on, did you put the reverse gear shims in?

Chris......

 

[ENSIGN]

Re: Prop Too Tight?

How many extra parts did you have left over? You're going to have to get a factory service manuel and the correct tools.Cheaper to let a dealer repair it.

 

[chargerboy]

Re: Prop Too Tight?

Chris, when the prop is tight, I can't move the shift selector. And no, I can't find any shims in the diagrams that I should have installed. From what I could see, the carrier had a gear, a large washer, a rubber o-ring and that was all connected to the body of the carrier, inside were some needle bearings. I didn't see anywhere inside the lower unit or on the carrier itself where shims should have gone.

Ensign, that might be what I end up doing, although I got my torque wrench today, checked the retainer, and i was only 20 pounds shy of the reading. It budged 1/8th of a turn and still didn't help. I didn't have any parts at all left over from putting it all back together except for a small metal pin that came with my new water pump that I couldn't figure where it goes since it didn't come off the old unit or in the box.

 

[achris]

Re: Prop Too Tight?

When the prop is tightened down, does the prop push up against the edge of the gear housing? Can you turn the prop easily or is it stiff?......

And the rest of the question?

... I didn't have any parts at all left over from putting it all back together except for a small metal pin that came with my new water pump that I couldn't figure where it goes since it didn't come off the old unit or in the box.

That pin is not for use on these drive...

Chris.....

 

[chargerboy]

Re: Prop Too Tight?

Well I figured out the answer, one of my friends came by to look at the prop today and said I had a worn, and wrong sized thrust washer. He tried one of his props with a thrust washer on it and it worked just fine. I don't know how the previous owner ran it like that, but I will go see if I can find a thicker washer tomorrow. Thanks a lot everybody for your time and help.