Has any body tried to replace the thru hug exh prop. I can get the nut off with an impac but can not remove. Went to the dealer and was told that this model needs to be burnt off because of the rubber shock hub. I guess that I can thank the heavens that all I wanted to do was put a new prop on and use the old as a spare.. What the hell would you do out in the shallows at low tide and you bang up a prop. Any help in this crazy problem will surelly be appreciated. I've included a picture of the prop. This is on a 2002 Merc, 25hp EL long shaft. I have never heard of a prop that had to be burnt off, dammit it really pisses me off to think that if I don't have the ability or whatever to build a better system than this, I'll be dammed. .
25hp Merc Prop woes
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I think you may have misinterpreted what was meant. Evidently the splined hub is siezed on the propelleer shaft. Its alamost impossible to use a puller without damaging the lower gear unit or busting the prop. So remember when you do get it off to use anti sieze or a grease at the minimum on the hub and shaft splines, and to remove the prop periodically. Local conditions in which theboat is used as to water type and contaminates in the water will dictate how often to remove prop just to make sure its not siezed, as well as check for fishing line etc wrapped around prop shaft which will lead to a scored shaft and ruined lower unit seal and major damage to the lower unit. OK, now how to get the prop off, it has to be as that dealer says burned off, but Let me phrase it a better way.
First remove the props retaining nut and thrust washer and locking tab if used under the nut. Then with the foot in the full down position take a piece of rope and fashion a noose around one or two of the blades and secure it to the lower leg of the outboard. This is going to serve as a restraint so when the prop flys off it stays on thew shaft or drops nearby and does not go flying and get damaged any more than it will when its removed.
Now take a hand held Oxygen Acetylene, MAPP or Propane torch and heat between the supporting webs of the prop and the round section the prop shaft goes though. It will get hot, but not to the point you will damage any internal seals or parts in the lower unit or even harm the prop, as if its going to come off it will come off long before the prop gets to the point of being damaged from the heat. Inside this area is a rubber bushing (hub) that has a metal core with splines vulcanized to it. This hubs function is for reducing forward to reverse shock loads, not protect it from rocks and such as commonly heard, its merely a shock absorber when you go from forward to reverse in a boat. What happens when you heat this outer portion around the splined hub is the layer of rubber in contact with the props hub bore gets soft and liquid, and since these hubs are compressed when the are installed, the compression in the hub in addition to its outer layer being liquid and soft now will cause the prop to literally fly off the prop shaft.
Fine, now you have the prop off the shaft but the splined hub and probably a large portion of the rubber is still on the shaft. Now cut the rubber away so your down to the basic metal splined section of the hub. Use a grinder, file or such and file it along its length until you just start to penetrate through and it will come off with a little force or maybe all by its own. Do not appl;y heat to this metal portion as it will now trasfer heat to the shaft (before the rubber hub insulated the heat away from the shaft), or perhaps you can put a puller against the forward thrust washer and pull it that way, but in any case just basically splitting this piece will allow it to come off pretty easy. Most either aluminum or brass and work very easy with a file or grinder.
While your heating this hub section heat it all around a little at a time so its heated uniformily/
So now clean up that shaft with a wire brush grease it up with anti sieze and reinstall your new prop. Take your old prop to a prop repair station and have them replace the rubber hub. Its a common repair and will run anywhere from $20 to 40 and can usually be done while you wait After the hub is replaced you now have a spare which is as good in every sense of the way a brand new prop would be, unless its bent or dinged up, which of course can also be fixed at any prop repair station.
I had at one time worked props for some large major manufacturers as well as been a partner in a prop repair station back up until 1985 when I got fed up with boats and marine stuff and got out. It shold only take 5 or 10 minutes to remove even the most stubborn props on outdrives and outboards with the larger percentage of the time spent in applying heat.
Its a real simple straight forward method that is recomended by the factories. At one time I was certified by Mercury Marine, OMC, Volvo, Yamaha, Johnson evinrude and Michigan Wheel and Propco as a certified repair tech on their propellers and castings repair. Its easy, so go for it and put the price of labor for a marina to do it to your own good use, instead of a quick fast buck for them.
First remove the props retaining nut and thrust washer and locking tab if used under the nut. Then with the foot in the full down position take a piece of rope and fashion a noose around one or two of the blades and secure it to the lower leg of the outboard. This is going to serve as a restraint so when the prop flys off it stays on thew shaft or drops nearby and does not go flying and get damaged any more than it will when its removed.
Now take a hand held Oxygen Acetylene, MAPP or Propane torch and heat between the supporting webs of the prop and the round section the prop shaft goes though. It will get hot, but not to the point you will damage any internal seals or parts in the lower unit or even harm the prop, as if its going to come off it will come off long before the prop gets to the point of being damaged from the heat. Inside this area is a rubber bushing (hub) that has a metal core with splines vulcanized to it. This hubs function is for reducing forward to reverse shock loads, not protect it from rocks and such as commonly heard, its merely a shock absorber when you go from forward to reverse in a boat. What happens when you heat this outer portion around the splined hub is the layer of rubber in contact with the props hub bore gets soft and liquid, and since these hubs are compressed when the are installed, the compression in the hub in addition to its outer layer being liquid and soft now will cause the prop to literally fly off the prop shaft.
Fine, now you have the prop off the shaft but the splined hub and probably a large portion of the rubber is still on the shaft. Now cut the rubber away so your down to the basic metal splined section of the hub. Use a grinder, file or such and file it along its length until you just start to penetrate through and it will come off with a little force or maybe all by its own. Do not appl;y heat to this metal portion as it will now trasfer heat to the shaft (before the rubber hub insulated the heat away from the shaft), or perhaps you can put a puller against the forward thrust washer and pull it that way, but in any case just basically splitting this piece will allow it to come off pretty easy. Most either aluminum or brass and work very easy with a file or grinder.
While your heating this hub section heat it all around a little at a time so its heated uniformily/
So now clean up that shaft with a wire brush grease it up with anti sieze and reinstall your new prop. Take your old prop to a prop repair station and have them replace the rubber hub. Its a common repair and will run anywhere from $20 to 40 and can usually be done while you wait After the hub is replaced you now have a spare which is as good in every sense of the way a brand new prop would be, unless its bent or dinged up, which of course can also be fixed at any prop repair station.
I had at one time worked props for some large major manufacturers as well as been a partner in a prop repair station back up until 1985 when I got fed up with boats and marine stuff and got out. It shold only take 5 or 10 minutes to remove even the most stubborn props on outdrives and outboards with the larger percentage of the time spent in applying heat.
Its a real simple straight forward method that is recomended by the factories. At one time I was certified by Mercury Marine, OMC, Volvo, Yamaha, Johnson evinrude and Michigan Wheel and Propco as a certified repair tech on their propellers and castings repair. Its easy, so go for it and put the price of labor for a marina to do it to your own good use, instead of a quick fast buck for them.
Chipmaker Thanks, I probably misunderstood the mechanic. I've called a few other shops and they all say the same thing, so I conclude that I may want to go with a all aluminum prop if it's available. I understand the use of anti-sieze, but maybe when the dealer had it off a few months back they may not have used it....... Anyway thanks for the info,will be doing it this weekend if the weather permits....
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Ernieg
There was no link or assocaited image to your post, but your saying "if an aluminum propeller is available" am I understanding that as the prop on it now is not aluminum or stainless? Is it a composite type prop?
I would not think a composite prop would be repairable if it got heated up. I have never really dealt with any composite props except the ones they used to sell at one time for about 1/2 of what an aluminum one would cost and they recomended them as spares only, or the occasional plastic props on trolling motors etc. You may just have to sacrifice the entire prop and write it off if it is a composite.
There was no link or assocaited image to your post, but your saying "if an aluminum propeller is available" am I understanding that as the prop on it now is not aluminum or stainless? Is it a composite type prop?
I would not think a composite prop would be repairable if it got heated up. I have never really dealt with any composite props except the ones they used to sell at one time for about 1/2 of what an aluminum one would cost and they recomended them as spares only, or the occasional plastic props on trolling motors etc. You may just have to sacrifice the entire prop and write it off if it is a composite.
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I know a lot of you folks have boats, and props are a big item, but there are alternatives to buying a name brand (Merc, OMC, yamaha, etc etc) prop from the dealer.There are two or three aftermarket prop makers out there that make props equal to or better than OEM props, and in most cases these props usually are better in terms of durability. Michigan Wheel and Propco are two extremely good companies. OEM types tend to use a less ductile type of aluminum which is more like a die casting alloy, which breaks quicker when it gets banged. The other two manufacturers make their props using sandcasting methods, and while they may not have that fancy deep gloss paint job, they are 110% functional and you would not know the difference in operation between OEM and the aftermarket, expcet in your wallet with money saved. The aftermarket props usually can be straightened up easier without a chunk breaking out. The high gloss paint adds nothing after a hour or two, so why pay for it.
You would not believe how many boats have the wrong prop on them, even as delivered from a dealer. The prop a new boat has on it may run fine with the boat as delivered but add a few more folks or some fishing gear and all of a sudden it don';t work right anymore. Its hard to have your cake and eat it too with a boat and prop and motor combination unless you have gobs of excess horsepower. Your boat in its usually used configuration (example: 3 adults, 1 dog, two tackle boxes and case of beer full tank of fuel) should be able to be placed at full throttle and your max rpm of your engine should be able to be obtained. If the rpm is lower than your engines max rpm (listed in its owners manual) your over propped or over loaded, so you need to drop down in pitch of the prop or reduce the load (kick out the dog etc).
If your able to run higher or over the max rpm, your under propped, so add anaother case of beer etc, or go to a higher pitched prop. Lugging a boat motor is as bad as over reving it, and even with having the wrong prop but never running it at max rpms or loads it still puts more wear and strain on your motor. Usually if you can get within 500 rpm one way or the other your in the ball game. And its not uncommon to have the need for two or more props to meet conditions, but its rare to find folks that will take the time or spend the money to get whats required. Hot days a boat or other engines will run different than on cool days.
Having a stainless steel prop on a boat that is used in poluted or contaminated or salt / brackish water will accelerate your aluminum parts of your outboard or stern drive to corrode faster. An aluminum prop will not accelerate the corrosion as it does not setup galvanic action between as many dissimilar metals. So if you run a stainless prop keep a close eye on your zinc anode.
But if you want to save some money and get a quality product give Michigan Wheel or Propco props a try. You'll be more than satisfied. I have no vested interests in these companies, just experience in their products.
Its also nice to be able to order parts and accessories before hand than puttingyour boat in the water and finding out you should have done this or that and be at the mercy of a Marina and their overly inflated prices. While a spare prop is like having a spare tire, its really good to have just incase. But if you do not have the tools along to change it or have the tools and it won';t come off, you may as well not have any prop with you for a spare. Check those props and make sure they are in good condition, can be removed easily, and no fishing line from prevous use is wrapped between it and the prop shaft that can lead to a worn or cut lower unit seal. If you fish or runyour boat in waters with heavy fishing use, its a good idea to pull a prop p[eriodically and check for wrapped up fishing line. If yu find some, then remove the drain plug on your lower unit, and drain out just a small amount of lube. If its milky you have water in it, so you may have a faulty leaking propshaft seal. If it looks normal, top off if needed and replace plug and bump on. Its not uncommon for water to get in this torpedo or lower unit, and during cold weather it can freeze and bust a lower unit gearcase. It happens here in the Gulf region and I am sure it would be more of a problem up north, so its a quick and eay check to make and it can save big bucks down the road. I have seen many lower units that containd nothing but water. But the boats worked just fine.
You would not believe how many boats have the wrong prop on them, even as delivered from a dealer. The prop a new boat has on it may run fine with the boat as delivered but add a few more folks or some fishing gear and all of a sudden it don';t work right anymore. Its hard to have your cake and eat it too with a boat and prop and motor combination unless you have gobs of excess horsepower. Your boat in its usually used configuration (example: 3 adults, 1 dog, two tackle boxes and case of beer full tank of fuel) should be able to be placed at full throttle and your max rpm of your engine should be able to be obtained. If the rpm is lower than your engines max rpm (listed in its owners manual) your over propped or over loaded, so you need to drop down in pitch of the prop or reduce the load (kick out the dog etc).
If your able to run higher or over the max rpm, your under propped, so add anaother case of beer etc, or go to a higher pitched prop. Lugging a boat motor is as bad as over reving it, and even with having the wrong prop but never running it at max rpms or loads it still puts more wear and strain on your motor. Usually if you can get within 500 rpm one way or the other your in the ball game. And its not uncommon to have the need for two or more props to meet conditions, but its rare to find folks that will take the time or spend the money to get whats required. Hot days a boat or other engines will run different than on cool days.
Having a stainless steel prop on a boat that is used in poluted or contaminated or salt / brackish water will accelerate your aluminum parts of your outboard or stern drive to corrode faster. An aluminum prop will not accelerate the corrosion as it does not setup galvanic action between as many dissimilar metals. So if you run a stainless prop keep a close eye on your zinc anode.
But if you want to save some money and get a quality product give Michigan Wheel or Propco props a try. You'll be more than satisfied. I have no vested interests in these companies, just experience in their products.
Its also nice to be able to order parts and accessories before hand than puttingyour boat in the water and finding out you should have done this or that and be at the mercy of a Marina and their overly inflated prices. While a spare prop is like having a spare tire, its really good to have just incase. But if you do not have the tools along to change it or have the tools and it won';t come off, you may as well not have any prop with you for a spare. Check those props and make sure they are in good condition, can be removed easily, and no fishing line from prevous use is wrapped between it and the prop shaft that can lead to a worn or cut lower unit seal. If you fish or runyour boat in waters with heavy fishing use, its a good idea to pull a prop p[eriodically and check for wrapped up fishing line. If yu find some, then remove the drain plug on your lower unit, and drain out just a small amount of lube. If its milky you have water in it, so you may have a faulty leaking propshaft seal. If it looks normal, top off if needed and replace plug and bump on. Its not uncommon for water to get in this torpedo or lower unit, and during cold weather it can freeze and bust a lower unit gearcase. It happens here in the Gulf region and I am sure it would be more of a problem up north, so its a quick and eay check to make and it can save big bucks down the road. I have seen many lower units that containd nothing but water. But the boats worked just fine.
If you do end up trashing the prop; I would suggest taking a look at Michigan Wheel props. I have two of them for my Sea Ray and found that the Michigan Wheel 16 x 16 prop actually does much better than the stainless prop I originally had on. They are VERY reasonably priced and much cheaper than OEM.
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You could also try www.westmarine.com. They should have a few options. It's woth a look anyway.
Regards,
Greg
Regards,
Greg
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I imagine living in the area you live you shuld have quite a lot of options on where you buy a prop if needed at. MArinas and boat supply places in Florida are like slot machines in Nevada. There all over the place.
Mailorder would probably be the cheapest if $$ is an issue.
Mailorder would probably be the cheapest if $$ is an issue.
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I know that the sterndrive engines usually have a propping range of about 400 RPM generally I think the outboards are the same. Chippy is right, a boat may leave the factory propped as tested but may not be correct once the customer loads the boat with all kinds of stuff. I deal with this almost daily working as a boat tester for FORMULA BOATS. We have a guide line from the engine manufacturers as to how to load the the boat for propping. Usually half load. As for the stuck prop the old torch is probably the answer, it is recommended by Mercury marine to remove and grease the prop shaft every 2 months in fresh water and every month in salt water. As for prop type the aluminum works well on small boats but when you get into bigger and heavier boats the don't work so well.
Well after all this time, I, finally got roung to pulling the prop, and it came off easily. At first I thought that I wouldn't need to get a new hub pressed in but for 50 bucks I decided to have the hub installed and picked up a SS from West Marine in Holiday last weekend. Plan on some red fish for dinner next weekend.
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So, did you have to heat it up to get it off or what? I assume it was an alauminum prop then and not a composite type, since you elected to have th hub replaced. I sure wished I could have gotten that kind of hub replacement money when I was doing props. We used to charge $20 for hubs up to 40 hp, 30 for hubs up to 150 hp and all other hubs in larger outboards and all stern drives averaged $50. Replacement is quick and is easy with a press and funnel. You would be surprised at just how much difference i the outside diameter of a new hub is than the bore in the prop into which it is pressed is. But it slips into that bore pretty easy with a hydraulic press and driver / funnel and some lube.
When you speak of redfish are you referring top red snapper or red drum....Locals here call red drum redfish, and call snappers simply reds or snapper......... Sure is some fine eating, as is most salt water species. Grouper, Skamp, spade, sheepshead, and heck we eat amber jack and blues, and they are just fine, but a lot of folks tell you that they are full of worms and not edible.
Has the cobia run in yur area yet? The cobia run here in the pan handle is just about over but spanish are still very much active and hitting hard.
When you speak of redfish are you referring top red snapper or red drum....Locals here call red drum redfish, and call snappers simply reds or snapper......... Sure is some fine eating, as is most salt water species. Grouper, Skamp, spade, sheepshead, and heck we eat amber jack and blues, and they are just fine, but a lot of folks tell you that they are full of worms and not edible.
Has the cobia run in yur area yet? The cobia run here in the pan handle is just about over but spanish are still very much active and hitting hard.
(When you speak of redfish are you referring top red snapper or red drum....Locals here call red drum redfish, and call snappers simply reds or snapper......... Sure is some fine eating) Speaking of fish,I was the lucky one this past sat. 1 red fish (red drum) and 20" sea trout. All very good eating. Like to cook over a open wood fire or a wood fired smoker. Fantastic!!!!!!!!!! :smoking:
Chipmaker, I am sorry that it's taken so long to get back to you. Yes the prop was heated, only not as hot as I thought . I did nit see any heat damage on th end of the hub but better judgement told me to get a new insert. The prop ia aluminum. I know that this stainless prop is of same size and pitch as the factory prop but it mkes me feel faster. Probably because it's shinny.
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