Go Back  The Hull Truth - Boating and Fishing Forum > BOATING FORUMS > The Boating Forum
Reload this Page >

So today, I bent my Prop shaft on my Yam F300

Notices
Like Tree1Likes
  • 1 Post By mdees88

So today, I bent my Prop shaft on my Yam F300

Old 08-20-2017, 02:10 PM
  #1  
Senior Member
Thread Starter
 
Join Date: Oct 2013
Location: South LA
Posts: 802
Default So today, I bent my Prop shaft on my Yam F300

I hit something hiding under the surface, doing about 40 mph. Fortunately, no boat damage, but felt the obvious lower unit damage.

For those who fish out of Cocodrie, LA, I'll post the coordinates after I get them off of my machine. Briefly, it's about a mile south of El Rincon, heading dead on target to the sulfur mine.

Edited to add debris detail:
N 29deg08.113'
W090deg40.374'

It's obvious the prop shaft is bent. Just a scuff mark on the outer casing, prop doesn't even look bent. Prop won't spin, and you can see that it doesn't match up with equal clearances between the housing and prop. It will turn, and vibrates like hell at low rpm's. Ran okay at about 30 mph coming in.

What now? I'm okay when it comes to mechanical stuff. I usually fix my own forklifts, and I've changed the water pump on my F225. I have access to a machine shop if needed.

Should I pay an expert, or tackle this myself?
I have insurance, but not sure of my deductible... $1000 if I had to guess.
Brokenline is offline  
Old 08-20-2017, 02:37 PM
  #2  
Senior Member
 
Join Date: Nov 2016
Location: Stuart Fl
Posts: 298
Default

It's a $750 job , at least that what it cost me on my 08 HPDI 250 .I took my lower unit off and took it to the mechanic .
My buddy did his own , but the shaft was like three hundred , I think . He tried to straighten it in a arbor press , didn't have much luck .
It's a two kinds of metal shaft , stainless friction welded to chrome moly , I think .
Smitty 45 is offline  
Old 08-20-2017, 02:40 PM
  #3  
Senior MemberCaptains Club Member
 
Join Date: Mar 2002
Location: FL
Posts: 18,841
Default

My experience with bent propshafts (unfortunately have had 2 - ug ) has been that you will never be able to get the shaft straight. And remember that you have bearings and seals in there - and it ain't gonna be cheap whatever you decide to do.
First Light is offline  
Old 08-20-2017, 02:48 PM
  #4  
Senior Member
 
Join Date: Jan 2011
Location: englewood, florida
Posts: 5,329
Default

are you certain its the shaft and not the prop?...the prop could be tweaked to do what you have described...you need to pull the prop and check the shaft before making a decision...

this would be an insurance claim in the event the damage is significant if you choose to make one....now that I mentioned that this will turn into a "never use insurance for a small claim" thread and I apologize for that...
bladenbullet is offline  
Old 08-20-2017, 03:03 PM
  #5  
Senior Member
Thread Starter
 
Join Date: Oct 2013
Location: South LA
Posts: 802
Default

Thanks for the replies so far.

I just had an acquaintance, who works as an outboard mechanic look at it. It's definitely the prop shaft, and he said it's bent pretty badly. Mentioned that hopefully gears aren't damaged.

I guess my primary question is, Is this a job I should tackle myself or let them get on it?

Brokenline is offline  
Old 08-20-2017, 03:13 PM
  #6  
Admirals Club Admiral's Club Member
 
Join Date: Nov 2011
Location: sarasota
Posts: 3,550
Default

It depends on what u do for a living....

Doctor, lawyer, gemologist, cpa, etc....call a mechanic

Can barely afford to fuel my f300.. have nothing better to do...have the correct tools..and can afford to pay a mechanic when it gets screwed up...by all means go for it..

And post pics.
gumpire is offline  
Old 08-20-2017, 04:35 PM
  #7  
Senior Member
 
Join Date: Dec 2010
Location: Connecticut & Misquamicut, RI
Posts: 723
Default

Drop the LU. Buy and new shaft and seals and have at it. Worst case, you take the LU to a mechanic if you can't get it done.
RustyGaff is offline  
Old 08-20-2017, 04:45 PM
  #8  
Admirals Club Admiral's Club Member
 
Join Date: Jul 2014
Location: Stapleton, AL
Posts: 2,707
Default

Originally Posted by Brokenline View Post
Mentioned that hopefully gears aren't damaged.

I guess my primary question is, Is this a job I should tackle myself or let them get on it?

Let me tell you what happened to my coworker a month ago. He's a charter capt. and he had his ipilot set up next to an oil rig. it lost signal and he drifted into the rig. he cranked his yam f250 and when he was moving away from the rig the prop hit the rig leg and shut the motor off. he cranked it up and drove away. he fished the rest of the day no problem, very little damage to prop.

next trip out after going 10 miles his lower unit starts whining... 5 more miles it locks up. lifted lower unit out of water and the paint melted off it got so hot. He filed the incident with his insurance and got an ENTIRE lower unit for the price of his deductable ($750) I think. This is the second brand new lower he has got through insurance claims in the last 8 years. My point is you do not know how much crap is damaged or misaligned. Would be bad to fix prop shaft yourself then have gears in lower tear up 3 trips later. You have insurance for a reason... use it
bladenbullet likes this.
mdees88 is offline  
Old 08-20-2017, 04:49 PM
  #9  
Senior Member
 
Join Date: Jan 2006
Location: Sunny florida
Posts: 23,041
Default

Originally Posted by Brokenline View Post
Thanks for the replies so far.

I just had an acquaintance, who works as an outboard mechanic look at it. It's definitely the prop shaft, and he said it's bent pretty badly. Mentioned that hopefully gears aren't damaged.

I guess my primary question is, Is this a job I should tackle myself or let them get on it?

Probably not. May require special tools, presses. How competent are YOU?
billinstuart is offline  
Old 08-20-2017, 05:02 PM
  #10  
Senior Member
 
Join Date: May 2005
Location:
Posts: 843
Default

Go insurance route, thats why you pay the premium. Its a $1k accident for your deductible
Smoke n Mirrors is offline  
Old 08-20-2017, 05:11 PM
  #11  
Admirals Club Admiral's Club Member
 
Join Date: Nov 2008
Location: Jupiter, FL
Posts: 2,068
Default

Here's the high level work scope

Remove lower
Remove shift rod assy
Remove hub bolts
Need slide hammer attached to prop shaft threads to remove assy
Need to press off gear to disassemble and replace shaft

Pretty easy with right slide hammer and a press with right split plates.
lobsdiver1 is offline  
Old 08-20-2017, 05:25 PM
  #12  
Admirals Club Admiral's Club Member
 
Join Date: Jul 2014
Location: Stapleton, AL
Posts: 2,707
Default

Originally Posted by Brokenline View Post
It will turn, and vibrates like hell at low rpm's. Ran okay at about 30 mph coming in.
Who knows how much additional damage you caused running 30mph with a bent prop shaft, surely that had to add some serious wear and tear to the gears in that time. Did you pull the lower drain plug and see how much metal shavings were on the plug?

If this was a $200 DIY job and I was 100% sure of the extent of the damages I would defiantly entertain the idea fixing it myself. But we're talking about damage to a lower unit (the second most expensive item on a motor besides the powerhead). Heck even your mechanic said "hopefully" there's no damage to the gears.

This seems like a no brainer insurance claim to me...
mdees88 is offline  
Old 08-20-2017, 05:37 PM
  #13  
Senior MemberCaptains Club Member
 
Join Date: Apr 2004
Location:
Posts: 1,510
Default

Drain your lower unit and carefully examine. If you see metal pieces you know you have extensive damage. Slowly rotate your prop shaft by hand. If you feel roughness you have extensive damage. If you don't find extensive damage you may have other problems, but the odds turn in your favor that you do not. I used the jack technique and successfully repaired my shaft to a .003 inch runout, within spec. I used a scissor jack applied against the anticavitation plate and the prop nut. If you go this route you will need a dial indicator and stand. I got mine online for $33 and worked fine. Otherwise borrow one.

Some will say you are crazy to use this technique on a tight tolerance, high cost, lower unit drive train. It is possible to break something but the way I see it you don't have much to lose. If you pay to open the lower unit and straighten or replace the shaft you are looking at $750-1,000. If you have to replace additional LU components your costs will go up by hundred dollar increments. The worst is if the Bearing carrier cracks. That is probably in the $3-500 range. I fixed my bent shaft for $0 and did it in an hour.
Inlander is offline  
Old 08-20-2017, 05:51 PM
  #14  
Senior Member
 
Join Date: Dec 2014
Location: 70605
Posts: 2,161
Default

Pull LU and drop at shop for inspection and estimate. Hold off on submitting claim until you have a number to make that decision. Did you pull plug on LU and was there any water intrusion?
Kenner 23 is offline  
Old 08-20-2017, 07:01 PM
  #15  
Senior Member
 
Join Date: Dec 2003
Location: NorCal
Posts: 2,748
Default

If it's as easy to fix as some are suggesting a pro shouldn't charge that much, I would call around and get estimates.
jayyy is offline  
Old 08-20-2017, 07:05 PM
  #16  
Admirals Club Admiral's Club Member
 
Join Date: Sep 2014
Location: Hinesville GA
Posts: 4,670
Default

Read the service manual on what you need to do to rebuild your lower unit (shims gauges measurements etc) then file an insurance claim.
Yes I had one bent recently and now have a new lower unit.
Gnrphil is offline  
Old 08-20-2017, 07:14 PM
  #17  
Senior Member
 
Join Date: Nov 2016
Location: Stuart Fl
Posts: 298
Default

I believe the tolerance is .003 ? Not a job for the tailgate ?
Smitty 45 is offline  
Old 08-26-2017, 06:44 PM
  #18  
Senior Member
 
Join Date: Dec 2014
Location: 70605
Posts: 2,161
Default

Update???
Kenner 23 is offline  

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are Off


Thread Tools
Search this Thread