That I've never come to. Only seen it done in a plant maintenance shop with a very long press.
Removing the Propeller Shaft Flange - H41AC
- Thread starter dkinzer
- Start date
Heat is a good friend here. I had a difficult flange to remove . Heated to 350 to 400 degrees -which is well below any metal transition temps. Two benefits- 1st the flange expands and you can add more WD or Liq. wrench. 2nd the flange expansion makes it easier to remove. I did have room for a puller on my boat but it took several careful tries.
Heat would be more like a torrid concubine here. With a big hub like this, an air/acetylene torch would be the minimum but an oxy/acetylene torch would probably be best to move things along.
Unfortunately, this doesn't help @Rich Stidger getting the flange back on again unless he resorts to a split flange. I believe a split flange is recommended to be installed initially by a pro shop first.
I wonder if anyone with a dripless mechanical seal is reading this and realizes the work required every 6-8 years to renew the bellows.
No need to send coupling to machine shaft it that is your question. I reused mine. I actually had a new split coupling I was going to use but could not get it on the shaft. Still don't know why it would not go on. If I remember I was able to tap the old coupling back on without much trouble. I had the shaft well lubricated.
It's worth a try with the flange at 200°F and a quick swipe of oil before it goes on. May well do the trick. I would check it for angularity before getting into alignment with the Xmission flange.
The coefficient of thermal expansion for the steel flange is probably about 6.5 microinches per degree Farenheit per inch. Given the 1-1/4" diameter hole, heating to 200*F (say 150* above ambient) would yield an expansion of the hole to about 1.2512". If the shaft itself is exactly 1.250" that should allow the flange to slip relatively easily. You could also toss it in your oven at 350* and get yourself some additional space.
"Angularity" - Does this mean that the flange might not be perfectly perpendicular to the shaft? If this is possible, how does one check for the precise alignment and if it is not correct, how is it corrected? IIRC, the alignment spec is 0.001" per inch diameter of the flange. So the flange to shaft alignment has to be darn near perfect in order to align the shaft flange with the transmission flange.
If there's a God above, please don't let that happen or it's off to the machine shop we go.
Rotate the prop shaft flange and measure the clearance at a single point relative to a fixed object while pressed against that fixed object. That fixed object will be your Xmission flange. That clearance must (we hope and pray) remain within 0.001/inch of flange diameter.
It's off to the @#*&%#*&^%*! machine shop we go to see if they can correct it or replace the whole assembly.
Unfortunately, yes. But FIRST, the prop shaft flange has to be perfectly aligned to the prop shaft and THEN the prop shaft flange is aligned to the transmission flange by kicking the
out of the engine, UP, DOWN, LEFT, RIGHT, IN, OUT, ROUND AND ROUND until you're blue in the face. Oh yeah, and then after you do all that, remember that you should have loosened the engine supports so the engine would move when you kick the out of it.Engine alignment, the making of a man OR alternatively, the breaking of a man.
Attached are the instructions I started with decades ago (two anyway) and have trimmed them back to suit myself. They'll help you to understand what you're trying to achieve and enable you to streamline where you see fit.
I'll pray for you.
Will you be able to clear the rudder ? Split flange in the picture ?
Prop shaft is offset to stbd, so no issues clearing the rudder with my MaxProp.
To keep my mental heath I installed a Sigma drive, so no more engine alignment and flange troubles. It alowes a 3° of center misalignment in any plane. Costs a lot, but mental health has a price
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I would be interested in trying an inductive heater unit now that they are easy to buy.
Original one we purchased for the low low price of $500, is the "Mini-Ductor II". Now they have competition, and a chinese clone can be had on amazon or whatever for $200
They come with a bunch of different sized coils meant for rusty fasteners, but the most useful coils are long and flexible, so you can wrap it around any metal object a few times, and heat the metal in seconds without a flame.
They made life easy in some cases, with no risk to damaging rubber dust boots or whatever else was near.
With a torch you can control where the heat goes, and get the flange hotter than the shaft. With practise you can do that with the induction heater tool, but not quite to the same level of control. So that might be a problem in this case. They also heat quickly so you need to make sure you don't get it too hot, depending on the task.. Hold that trigger and steel is red in a relatively short time.
Nice to have when you don't want a flame, or even gas and hoses, while working in a tight space.
Has anyone tried them for this type of task ?
I remember playing with an induction heater about half a century ago back in class. What we were looking at was the penetration of heating as a function of induction frequency. Couldn't tell you what the relationship was for anything now. If you can't get really fast surface heating, all is lost.
The hub is so thick, you know it's going to heat the shaft as it slowly comes up to temperature.
Ralph,
I agree with you.
The concept of using heat to separate concentric items depends on the outer mass expanding much faster than the inner one..
If they both heat equally, assuming that they both have similar thermal expansion coefficients, you’re just wasting time and energy.
For separation of the flanges, I still believe that a socket located in the centre, and using bolts to press them apart has the most promise
That of course is the method for driving the prop shaft flange off the shaft. However, when things get sticky, you may find yourself looking for an assist such as :
............. which is the only way when you've got a big hub as these things do.
This, not so much :
this bolt is driving me nuts, i keep loosing no matter what i do, any solution at this?A fervent religious belief.
A few pennies in the poor box every week.
And for you non-believing heathens, make sure the big hex nut on the Xmission shaft is bloody tight
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