1974 mercury 110 (9.8hp) Prop HELP !

[mjbrueck]

I just checked Propco's website and they only have the 9x9 replacement. If you can't find anyone that makes a new replacement, check e-bay. <br /><br />Be careful with your rpms if you get a 9x7.5. If you're going to use that as your only prop you may greatly exceed your max rpms when lightly loaded. It would probably be worthwhile buying a tach. The 200 rpms/inch estimate is for higher pitched props. Going from 9.5 to 7.5 is a 27% decrease in pitch. With the extra slip going from a higher pitched 2 blade to a lower pitched 3 blade, your engine rpms will probably be 30-40% higher at any given speed. So when running in the 5000 rpm range with the 9x9.5, you may be increasing your rpms by 1500 or more with the 9x7.5 at the same speed.

 

[joemamma_222]

1974 mercury 110 (9.8hp) Prop HELP !

Hi All ! Just got off the Phone with mercury and they pretty much cant help me ! I've got a 1974 mercury 110 OB serial number 3924604 (9.8hp). It's on a 14 foot Sea Nymph. The 2 bladed prop is has now is getting pretty chewed. With 2 people in the boat It will plane out. Add my son and we are just pushing water. I wanted to get a new prop and Possibly Upgrade to a 3 bladed prop to get the Boat Up on pad. Is that correct thinking on my part ? Anyway Mercury cant give me a replacement prop... Am I stuck ? They did say that I was close to 1000lbs so I would need a 3 blade, but thats all they could say. We figured my Pitch is a 9.5 (2blade Original equip) she said the other Prop was the 3 blade supplied with the 110 and it was a 7.5 pitch. Anyone know where I could Find one of these ?<br />Thanks !!!<br />Joe In Ohio PUSHING water.....

 

[joemamma_222]

Re: 1974 mercury 110 (9.8hp) Prop HELP !

Ok thanks D. Lemme know How the preformance goes ! Are you sure thats a 7" pitch on the 3 blade ? The only reason I ask is that the Mercury Factory had said it was a 3 bladed 7.5" OEM. <br /><br />So to take a step back I need part 48-47670A10 and the original part no was:48-47670A1 <br />Can I ask ya what you paid for one ?<br />I did call a Used parts guy here in town and he wants 70 to 90 bucks for a used 3 blade with maybe a nic or 2....thought that mighta been a little high for used.....<br />Thanks D. <br /><br />Joe.

 

[dajohnson53]

Re: 1974 mercury 110 (9.8hp) Prop HELP !

I just bought a prop for my 1974 merc. 110. I still have the box in the garage and will try to remember to look up the part number, size and pitch as soon as I get a chance. It's a three blade prop.<br /><br />For what it's worth: I bought this prop at the local merc. dealer. This guy definitely doesn't stock parts that aren't currently in demand. He implied that it is a common prop for mercs of that size, both older and newer than our '74s. <br /><br />I had looked several places on the internet for a replacement prop for this motor and couldn't find one anywhere.<br /><br />It fit correctly and is of the diameter and pitch recommended for this motor, so I gotta assume it's right.<br /><br />Also, somewhere -either in the service manual or the owners manual - there were two props listed for my motor. One, the original 2 bladed prop (which I had to destroy to remove, and was beat up anyway) was listed for pushing small, light boats up to a certain size. The other, a three bladed prop. was listed for kicker and heavier boat applications. Turns out, it's the three bladed prop the local guy stocks and again, the implication by him was that they don't carry the two bladed option. Makes me think that the two bladed option is NLA, and that's what Merc was looking for? I wanted the three bladed anyway, so that was fine with me. <br /><br />I'll try to get you the info within the next day.

 

[dajohnson53]

Re: 1974 mercury 110 (9.8hp) Prop HELP !

I think it's part 48-47670A10 superceded from 48-47670A1 , 8 3/4" DIA., 7" PITCH, 3 BLADES (ALUMINUM).<br /><br />If Iboats doesn't have one or you can't pick one up locally, check mercruiserparts.com - I believe they do.

 

[dajohnson53]

Re: 1974 mercury 110 (9.8hp) Prop HELP !

PS: mercruiserparts.com also shows a 2 bladed prop also being available:<br /><br />48-47922A10 PROPELLER ***'Y, 9" DIA., 10" PITCH, 2 BLADES (ALUMINUM) supercedes 48-47926A1 <br /><br />The local price was virtually the same as what I've seen on the web, fwiw.<br /><br />But like I said, in my factory manual, it shows both these as an option, the 2 blade for light small boats, the 3 blade for heavier boats and trolling/kicker applications.

 

[joemamma_222]

Re: 1974 mercury 110 (9.8hp) Prop HELP !

Thanks all ! I definately am Thinking 3 blade since I am a little on the heavy side. Appreciate it ! Do you think I could order from this guy ??? <br />Thanks again D. And MJ !! WOW it's really amaxing what one can acomplish ion this board !!<br />Anxiously awaiting your Reply !!!<br />Joe.

 

[dajohnson53]

Re: 1974 mercury 110 (9.8hp) Prop HELP !

Originally posted by joemamma_222:<br /> Thanks all ! I definately am Thinking 3 blade since I am a little on the heavy side. Appreciate it ! Do you think I could order from this guy ??? ...

If you're asking about my local guy, no. If you're asking about mercruiserparts.com, I've dealt with them and they're good, and I believe they carry it. You should check out the IBoats Megamall too because they might have it as well.

 

[mjbrueck]

Re: 1974 mercury 110 (9.8hp) Prop HELP !

$70 to $90 is pretty steep for a small used prop. I bought 2 new props for a Johnson 18 from Propco about 2 years ago and I paid around $50 each.

 

[dajohnson53]

Re: 1974 mercury 110 (9.8hp) Prop HELP !

Joe - I'll double check the actual box of the prop I have and get back to you. The info on parts numbers I posted above is from a vendor website, not the box from my prop. <br /><br />I seem to recall it cost around $70 or $80 new, locally.

 

[Motor Boater Bill]

Re: 1974 mercury 110 (9.8hp) Prop HELP !

Be aware that if you buy a used prop, unless it is either tested or guaranteed, there is no way to tell by looking at it whether the hub is spun--which may be the case if it has a "nick" in it. You can beat these prices on eBay with a used prop, but a re-hub can cost about $35-40, more if you have to ship it both ways of course. If you can find a new one on eBay that may be a good deal, but expect to pay for it.

 

[dajohnson53]

Re: 1974 mercury 110 (9.8hp) Prop HELP !

Originally posted by D.:<br /> Joe - I'll double check the actual box of the prop I have and get back to you. The info on parts numbers I posted above is from a vendor website, not the box from my prop. <br /><br />I seem to recall it cost around $70 or $80 new, locally.

From the box my prop came in:<br />Mercury Black Max <br />p/n 48-47670A10<br />8 3/4 diameter; 7 itch 3 blade aluminum<br />Merc 75 (7.5 hp) adn 110 (9.8 hp) outboards 1968 - 1984 with 8 thooth spline hub.<br /><br />My factory service manual has three aluminum prop options (and one bronze which I won't list)<br /><br />A 48-47670A1<br />9 inch, 7 pitch 3 blade aluminum<br />for auxilliary motor application<br /><br />(my guess is that this p/n has been superceded with the one I have, the difference being 9 inch vs. 8 3/4. I would also guess that the original p/n listed below for the other props have been superceded by new ones with an "A10" at the end in place of "A1")<br /><br />A 48-477922A1<br />9 inch, 9 pitch 2 blade aluminum<br />for 600 lbs and over<br /><br />A 48-47926A1<br />9 inch, 10 pitch 2 blade aluminum<br />for less than 750 lbs<br /><br />Hope you find a prop!

 

[dajohnson53]

Re: 1974 mercury 110 (9.8hp) Prop HELP !

Originally posted by joemamma_222:<br /> Ok thanks D. Lemme know How the preformance goes ! <br /><br />Joe.

Joe: Just wanted to report since I finally ran the motor with the new prop. It wasn't a long or totally adequate test, but my impression is: It worked great. My subjective impression is that ran at higher RPMs WOT than my old, original two blade prop, but this is purely a guess. Last year, I got the motor and just ran the old prop for 4 or 5 days last August, 99% trolling speed, just WOT enough to check it out and see how fast it would push my boat (a 21 ft welded aluminum, ~2500 lbs wet). I didn't have my GPS with me this time to compare WOT speed either, but it kind of "felt" like it was faster and higher RPMs - but we're talking hull-speed type thing, around 7 mph (maybe now it's 8!). I certainly can't rely on my memory for WOT rpm "feel" and dont' have a tach... trolling rpms, who knows. I'm tempted to buy a tiny tach just to see what it winds out at WOT. But my feeling is that for a kicker on this large boat, it is working better than the original prop.