How much faster is a 25HP Outboard over a 15HP?

[@2quack]

No life vest, no kill switch, and heavy metal! LOVE IT!

[@publicdefender77]

@2quack 😁Grew up in the 80s! This is how it was done.

[@NeasYellek]

Surprised you lived to tell by the new modern safety everything 😅

[@publicdefender77]

@@NeasYellek 🤣 exactly!

[@peteryeung111]

Agreed, best motor ever made. Easy to work on and reliable.

[@timlong1462]

I have a 25 on a fully loaded and decked 1440 and love it. Got it on a 0-6" adjustable jackplate with 4" setback and shallow water scoops. Thing rips hard. Put in a 4 blade stainless 10x12 prop with some nice cup to it. Got a few videos on my channel showing it running like a surface drive. Best so far was 34.5mph in about 6" of water. I discovered what the airboat guys have known a long time. Skinny water is fast water. You get something similar to ground effect and ride even higher on plane. Absolutely love this thing and how fast it will plane to hop sand bars and stuff on the river.

[@publicdefender77]

@@timlong1462 Yes, I have seen your setup. I think it's awesome. I would like a tiller extension. What do you recommend for that? I also have the same 200 hydrofoil you have but haven't put it on. Does that really help with speed or just keeping it on a plane with a higher motor?

[@timlong1462]

⁠​⁠@@publicdefender77 cool, I love the small outboard John boat community on YT, Always looking at other peoples videos to learn new stuff or get ideas. For my 2000 Johnson 25 a short bit of schedule 80 2" PVC conduit slid right over the tiller. Made it about 4"longer than the handle. I cut several slits and clamped it with hose clamps. Then 1.5" regular schedule 40 pvc will fit perfectly inside. Then I just used a round bail PTO pin/hitch pin to pin them together for quick detachment. Cheap if you have some laying around and sturdy The foil only helps for the first few seconds getting up. After that mine is several inches above the water if I've got the plate raised. I definitely know it helps in my case. I trim the motor down so the prop is actually pointed up, raise the plate to get clearance so the motor is actually pushing up on the transom. That thing will get up on plane in about 2 boat lengths and I can hole shot in about 2 feet of water. Th foil acts like an elevator surface, and also keeps my prop from ventilating for the first few seconds

[@publicdefender77]

@timlong1462 I ran a 2000 Johnson 30hp on this boat with a crappy prop and this 89 25 seems to be a little faster. It has the lighter mounting bracket and the exhaust is a little louder which i feel gives it more grunt. I have a heavy 14 foot fishing boat with a 40hp that I can only get 31 out of so weight is my biggest factor.

[@timlong1462]

@@publicdefender77 Weight is huge. I notice a decent difference just between a full tank and almost empty. I also sometimes think the older motors may have been rated different. I've met some guys on the river with 15's and 20's that move out. So much is weight, hull shape and prop so it's hard to pin down. I'd like to see a back to back with this 25 and a 30 if you still have it. This Old Outboard converted a 25 to the bigger 30 carb and I've considered it, just haven't been able to find one for a reasonable price. Also would be awesome to see the 40 on this boat if that's possible with the mounting.

[@PondBoys]

Boom!! nailed it good video bro just picked up a 25 Johnson tiller ,sold a 20 Evinrude a few months back love this motors

[@publicdefender77]

Thanks Brother. I am here in Wisconsin and if the good weather can hold out im hoping to run a 9.9 merc vs the 15 hp Rude. These older motors run forever!

[@TheWeekendAngler]

Great video! Showed up in my suggested tonight and I'm glad I clicked on it. I clicked the Thumbs Up and the Subscribe immediately after, too! Those smaller OMC (Johnson/Evinrude) outboards are bulletproof. Interesting tidbit of information for you; in that era, the 20, 25, 30, and 35 OMC outboards all used the same block. The horsepower difference was determined primarily (not exclusively, however) by intake and carburetor combinations. About 10 years ago, I purchased a J20CRESB (1990 Johnson 20hp) and although it pushed my 14' flat bottom jon boat fairly well, I wanted a little extra. I swapped intake manifolds to the one from the 35hp and ended up with a roughly 30hp outboard. Performance was amazing, and I think I picked up the intake on eBay for around $20. I was getting around 30mph GPS speed on that little jon boat.

[@publicdefender77]

Thank you, much appreciated! I love that about those motors. This 25 hp has very low hours and is super clean inside. I had a 1999 johnson 30 and this 25 seems to be as fast. I think it's a good one.

[@DaveDeBoer-g2f]

Both very good engines and very dependable

[@publicdefender77]

I love them both and will never sell them!

[@DizzyMan24]

Love those early 90s motors. Still have my dads 1994 20HP. Best run was 35MPH, but it was upgraded to 30HP and has a 15p prop, lol.

[@publicdefender77]

@DizzyMan24 that is fast from a 20! Or was that after putting the 30 carb and intake on it?

[@DizzyMan24]

@publicdefender77 After doing the 30HP upgrade. Not really sure how fast she ran as a 20HP.

[@Yamahaoutboardguy5090]

Those Evinrude 9.9s just keep on going.

[@publicdefender77]

Solid motors!

[@michaelyoung7911]

I have an 18hp and 40hp evinrude motor that I picked up last year I’m getting back running. Can’t wait to get them on the water.

[@publicdefender77]

@@michaelyoung7911 I love both of those motors! I have owned several of those as well. Still have a 40.

[@publicdefender77]

@@michaelyoung7911 Here is my 40. kzbin.info/www/bejne/jmOQlIGYetSWjJosi=5xkfIA2Py7Q79pQe

[@Goldminer63]

That's a fast little boat.

[@jacobswell2533]

I think you can go up a pitch or two and trim the motor up one hole with the 25hp. you should aim for 35 mph

[@publicdefender77]

@jacobswell2533 i did put a 15 pitch on and am getting the same speed. Maybe slightly less. It seems to chug a little more than the 13. If I lost 100lbs that would really help 😆

[@seriksson9721]

It probably depends a lot on which boat they are on and which propeller is used.

[@publicdefender77]

Yes, I am pretty sure I could get another 2mph out of the 15 and another 1 out of the 25.

[@flyinphil42]

The Nissan 18 hp also had an excellent power to weight ratio , it was 2 stroke weighed around 80 pounds.

[@publicdefender77]

@flyinphil42 what years were those?

[@flyinphil42]

@@publicdefender77I think they were the mid eighties models. I have seen some used models for sale , Nissan was bought out by Tohatsu , who now sells New outboard models that are made in the same factory in Japan as Mercury Marine. The Tohatsu comes with a five year warranty whereas the Mercury has a three year warranty, the Mercury costs more too.

[@publicdefender77]

@flyinphil42 years i haven't seem one in a very long time

[@flyinphil42]

⁠@@publicdefender77The Nissan 18 was basically a 15 hp with a bigger carburetor. It was a good motor , it’s a shame evinrude Johnson never had a version . I believe mercury had an 18 hp also in the early 80’s , probably Nissan copied it , made it better I’m guessing.

[@justinburkett5578]

I got my 15 evenrude when I was 13 . Best motor I ever had

[@publicdefender77]

@justinburkett5578 when I was 12 I got a 1985 15 to replace my 1960 10hp evinrude. The leap in technology blew my 13 year old mind!!

[@justinburkett5578]

@@publicdefender77 my 15 was a 1976 model and I also had the older model first I called it the egg head motor . Worlds of difference between them

[@garycuster5031]

It's not just speed but the thrust. I worked on evinrude outboards for many years. These two horse powers aren't in the same league.

[@publicdefender77]

@garycuster5031 That is awesome. Thanks for the comment. Huge Evinrude fan here. My Yes, you are exactly right. That's why I mentioned the 25 has over double the displacement. The torque is night and day. But, that 15 is at the top of power to weight ratio. Both excellent motors.

[@billyholderman1691]

Remember to adjust your turn knob screw for your idle adjustment

[@DaveDeBoer-g2f]

The 15 was under rated back in the

[@publicdefender77]

@@DaveDeBoer-g2f that motor was very underrated! That was engineering perfection in 74 when they introduced it.

[@johnfontenot7861]

25 Hp kicks butt.

[@publicdefender77]

@@johnfontenot7861 solid motor for an 89. I would rather have that than a 4 stroke

[@johnfontenot7861]

@@publicdefender77 i luv my 4 stroke!

[@JohnRusatsky]

Life jackets when you get tossed out

[@publicdefender77]

I live on the edge 😆

[@locker1325]

31 mph probably feels like 100 on that boat. Love a good 25 hp ob

[@publicdefender77]

Yea, she is screaming! Fun to pass larger boats or at least keep up with them.

[@micro4329]

I have a old 64 model sears semi vee hull its rated at 15 hp but i did run a 20 merc on it but traded it now have a 15 everude an a 20 hp Johnsons. Will see which one i like soon hopefully the merc was fast.

[@publicdefender77]

@@micro4329 Those are all strong motor. What year is the johnson 20?

[@dannyvision730]

Like the Miami Vice soundtrack.

[@bigjay6743]

I have an 18 murk on my 14 foot aluminum. She flies.

[@publicdefender77]

Those are solid motors!

[@goldcountryruss7035]

My 16'6" Western w/OMC 28spl has done 41MPH with a modified prop, will cruise @25 all day.

[@publicdefender77]

@@goldcountryruss7035 that's flying!

[@steelparkeroutdoors]

I have both same motors, I run the 25 on my 12' aluminum. used to run the 15 but with 2 people and all the gear, had to run pretty much wide open. the 25 runs half throttle.

[@publicdefender77]

The 25 has the torque. That really is the biggest difference, especially with adding weight. I bet that 12' flys with just 1 person.

[@huntercityss9142]

congrats both engines are great i think you should try changing the propeller with different twists maybe it will speed up more. traveling rarely we run at 100% power, so the engine with more horsepower will be more durable,

[@publicdefender77]

@huntercityss9142 Thank you! Yes, I need to do that on the 15. The 25 I tried many different props and the 13 seems to work the best.

[@bennyblanko3]

Oh, and I have a couple yamaha 8's (2 stroke and 4 stroke) and they are both too slow for that boat. I really like the 20 and 25's. You don't need to run full throttle, and they aren't too bad heavy.

[@frankartieta4887]

This seems about right ! A wee bit more than 7 mph faster ! Seems they both do a good enough job !

[@publicdefender77]

@frankartieta4887 to be fair to the 15hp it could be a little faster with a better prop. The real difference in in the torque. The 25 has the torque for when the boat has weight in it.

[@frankartieta4887]

Something to think about is the fact ! That double horse power gives no where near double speed ! Just a sad fact of physics ! It would likely take more than 4 times and more to out do the 15 in speed ! A 60 horsepower motor would not likely go double speed the 15 !

[@publicdefender77]

@frankartieta4887 exactly. You burn so much more gas just to get a few extra mph. The 15 wins the mpg battle 😁

[@frankartieta4887]

@@publicdefender77 I live in south Louisiana ! If you ever seen the show Swamp People and a episode featuring willie or junior edwards ! That where we have our camp ! Lots of lower speed in swamps full of submerged trees and dead heads ! A engine that is big enough is big enough ! If you get hung up ! They lighter too :) If you got to push ! We use a lot of go devil and surface drives ! They all slower than outboards ! Thing is they tough and speed dont matter !

[@publicdefender77]

@frankartieta4887 I'm here in Wisconsin off the Mississippi and several other rivers and I love that stuff. All of the footage was off the Mississippi river.

[@lars9631]

I can confirm those numbers. I have a boat of similar style and size and my 15hp Evinrude will do 23mph and my 30hp Evinrude will do 30mph. I also have a 25hp Mercury that does 30mph. All 2 stroke in perfect condition. You would think it would be more than a 7 mph difference.

[@publicdefender77]

@lars9631 Awesome! Something fun about simple little boats! I actually ran a 1999 Johnson 30 on this boat and didn't see better top speed numbers than the 25. To be fair to that motor the prop wasn't as nice as the 25 and could have used a 15 pitch. Thanks for watching!

[@rowynmaddocks6731]

The bigger motors have more torque

[@publicdefender77]

@rowynmaddocks6731 that torque makes all the difference in the world when there is weight in the boat or when you are fat like me 😆

[@jimdoughty3005]

I would be curious to know more about the motor set up on the boat which can effect the overall performance of the boat. Good speed from both engines but could he wring a little more out of both motors? Raising the engine on the transom to a point that the anti-cav plate is equal to or no higher than one inch above the keel would make a lot of difference in the performance. Maybe even trying other props for best RPM without going over the max RPM. I also noticed that he had more load in the boat with the 25hp than the 15. That would make a difference also.

[@publicdefender77]

@jimdoughty3005 yea you are exactly right. The 15hp would benefit from a 11" prop. The 25 I tried both a 13 and 15 and I seemed to get a tad more out of the 13.

[@jimdoughty3005]

@@publicdefender77 Yeah I can see that. "Rule of Thumb"....you can get or subtract 200rpm with each change of prop pitch. And that's fairly accurate. It was for me anyhow....LOL. You also have to watch the RPM's so you don't go to far over the rated MAX RPM. That there is a little misleading.....I have seen these JohnnyRudes do 5700 to 5800 rpm with no problems. I still run an 86' 90hp Rude that I rebuilt and propped out for 6Krpm. That was back in the 90's and it still runs great. Well I'm getttin off on a tangent here.....enjoyed the video very much. Hope to see more from you. Thanks!

[@publicdefender77]

@jimdoughty3005 I appreciate that. My channel is kind of all over the place with, boats, guns, snowmobiling, deer hunting. Fun stuff 😁!

[@matthewbond8874]

I had one of these 25s back in the late 80s. Paired it with a 14m sea nymph. Best boat I ever owned and it was fast and fun. Only thing different was I wore a life vest or at least had one at hand.🎽

[@publicdefender77]

@matthewbond8874 yea, Sea Nymphs are great. I had a nice 14 with a 35. I'm sitting on a throwable and you can probably see I have 2 life jackets in the bow area under the seat. Way too many wardens out on the Mississippi to not carry life jackets.

[@bennyblanko3]

My 9.9 is good, 15 is better, and 20 is perfect for my 14' decked lund semi V, but I'm not going near 30 mph! I usually don't run full throttle anyway, as it is a little sporty for that boat. Sometimes though!

[@Support2A]

I could water ski behind that! 😂

[@publicdefender77]

@@Support2A I learned on a 10hp evinrude😆. It had some torque!

[@Twilightzoneisreal]

You could probably play around with the prop pitch to make it faster, it being a light weight boat and all.

[@publicdefender77]

I definitely need to do that with the 15. I was planning on it until I dropped a spark plug. In the video you can see i had an extra prop in the bottom of the boat i was going to change out and show how much better it did. The 25 i did play with props and the 13 and 15 are basically the same. I get a few more rpms and about .5mph more from that 13. It also performs better with weight. Thanks for the comment.

[@allenbowick4716]

I have owned both, a '80 15 Evi & '85 25 Evi. Traded the 15 for the 25. Wish i would have kept it. Both are one pull wonders. Both rock solid dependable. Sure your new merc or yammi may be faster quieter and better on gas. But dependability i seriously doubt.

[@publicdefender77]

@allenbowick4716 these are bulletproof and in its year i don't know if any of the other brands were actually faster. Maybe I should fine a merc 25 and run them side by side

[@ericschulze5641]

​@@publicdefender77the merc. Is slightly better

[@publicdefender77]

@ericschulze5641 I had a Merc a 1988 15hp and it was slower than my 85 evinrude 15. The stupid shift on the tiller handle was also a pain in the ass.

[@Kq750.]

Were are you testing?? Look's familiar

[@publicdefender77]

@Kq750. I'm on the Mississippi & Black river out of Lacrosse Wi.

[@micro4329]

Not sure I'm in middle of trade for it just guessing late 70 or early 80 will let you know definitely later keep in touch

[@gregkobylarz8648]

How many HP is that boat rated for? Maybe 10 HP tops?

[@publicdefender77]

25hp is max hp

[@jool9392]

1 log and you're done for.

[@bastienforster4869]

what size boat do you have

[@publicdefender77]

@@bastienforster4869 14 foot mirrocraft

[@grant31781]

Wow that does run a bit faster than your heavier boats with more power. How much does that boat weight. It looks lighter built than my boat.

[@publicdefender77]

O yea, it's very light. That makes all the difference in the world.

[@ericvonp]

You look like Don Johnson

[@publicdefender77]

@@ericvonp 🤣🤣

[@SteveSutherland-n5l]

In my experience quite a bit.

[@tjsmith3060]

Still not a good comparison. With the 15 the boat was completely empty. With the 25 there was fishing gear and a bunch of water in the back.

[@publicdefender77]

@tjsmith3060 Yep. Sorry it didn't meet your standards! I really want to run the 15 with the 11 pitch prop next.

[@gman77gas]

When the lake is a mile long does it matter?

[@publicdefender77]

@gman77gas Not at all. Could do with a 2hp. I fish a long ways on the Mississippi so the speed helps.

[@ericschulze5641]

If a big thunder and lightning storm comes rolling in yea it matters

[@gregbell5975]

I don’t think your going to float if the boat goes over 🙈

[@donaldmartin4620]

The fact is I have a 15 hp outboard on my 16 ft Saturn amd then I have a 25 I use also on my 16 ft in fable Saturn to no match the 25 hp give way more power on the ocean amd waves amd I go way out to on my Saturn but only woth my 25 hp tho now for a lake 15 hp Easter amd get enough power out of it

[@meco72104]

30mph in that boat is really moving. How can you do a fair top speed run with the 15 hp only running on one cylinder?

[@publicdefender77]

It was running on 2 for most of the day. Running on 1 it can't even get on a plane.

[@meco72104]

​@@publicdefender77 would like to see a top speed run after the tune up.

[@publicdefender77]

@@meco72104 I will do it. I'm going to run it against a 1996 evinrude 15

[@meco72104]

@@publicdefender77 Looking forward to the video.

[@Phil-bz1kz]

I get about 38k with a 15hp, and 51k with a 25hp

[@publicdefender77]

Yea, that's right on!

[@Phil-bz1kz]

@@publicdefender77 thazs with a 14ft RIB

[@steveballard515]

10 hp

[@jameslakes5019]

😮 25 hp faster my 40hp Johnson runs 37 mph 16 ft hunting boat 25 hp marineer run 31 mph long shaft electric start

[@publicdefender77]

@jameslakes5019 my Evinrude 40hp only pushes my heavy 14' northwood to 31

[@john0johno650]

😊the music is a little too much

[@publicdefender77]

@@john0johno650 I appreciate that comment.

[@meatwad3000]

Its 10 hp faster😮

[@kylejudd532]

Unfortunately I wouldn’t trust either one to get me to the end of the dock! Any evinrude I ever had was a complete piece of trash, sorry but that’s my experience

[@publicdefender77]

@kylejudd532 that's too bad. They never have let me down. Owned over 10 and never been stranded that wasn't my own doing.

[@seriksson9721]

I'm no expert on the subject, but shouldn't a life jacket be appropriate when trying to break a speed record? It probably doesn't slow down the speed that much and is good if an accident happens. Nice program.

[@publicdefender77]

There is a life jacket in the boat and I'm sitting on a throwable. Thanks for being safety minded.

[@joeyjoe8892]

I'm not an expert on the subject either but don't you think they should put a skinnier guy on the boat maybe pick up another 10 Mi an hour

[@publicdefender77]

@joeyjoe8892 yes, thanks for pointing out that I'm fat 😆!

[@joeyjoe8892]

@@publicdefender77 that's not what I meant I meant for Weight Wise hey I'm no skinny guy either

[@allenbowick4716]

Life jackets are for pussies

[@sammyrothrock6981]

That 25 hauls

[@publicdefender77]

@@sammyrothrock6981 yea, that particular motor is very strong!

[@frankartieta4887]

I agree ! that 25 on that boat ! You better keep a eye on where you point it !

[@publicdefender77]

@@frankartieta4887 😁