1969 20' engine choice
 

I am currently redoing a 69 SF 20 ft. (Will raise transom 5 in and deck 3 or so for tank and bailing). In looking ahead for engine choice I really like the e-tec. My choices would be 115 or 150. In reading old posts, the majority opinion seems to be 150 or more for hp. However, an e-tec dealer says the 115 will be plenty for the boat. So,...I'm wondering if anyone out there is actually running a 115 (e-tec or other) and can give info. on performance. I will rarely be on flat ocean so top speed is not that impt. But ability to plane and plow through rough ocean is. I took a 1977 Johnson off the boat and that was more power than I need.

Re: 1969 20' engine choice
 

Back when they were made we always hung inline 150 Mercs on 20's, I had a 115 on my 18 and it was just fine but could have handled the 150 and I wished I had done that for mid range in swells, the 115 would bog a tad. Keep in mind I think these new DI motors may be a good deal stronger than the old ones too, so a new 115 may be comparable, maybe someone else can add something regarding that.

You might check here for a motor-You will have to email in for a quote on a motor but they are on the biggest buy program this year so nobody can sell them cheaper, it involves dealer incentives for commiting to X amount of motors. You would have to weigh it against how good a relationship you have with a dealer, they can get their feelings hurt if he's a good friend.

www.usavemarine.com

Re: 1969 20' engine choice
 

Yes, I am running a 115, an old '84 Johnson V-4, although on a 20' Seafari - probably a little heavier and more windage than your CC. The motor is sound and solid, and with 2 on board and a full tank of gas I top out at 31 mph GPS - like you say, on open ocean I rarely can run it there, but it has a nice comfortable cruise point at 25-27 mph, put it in 2 - 3 ft chop and I'm down to 15 - 18 mph, holds a plane down to about 10 mph - which I have had to do when faced with unexpected 5 - 8' slop - would choose not to repeat that, thank you :eek:

If I had an open wallet, I would look at a 135, either an Etec or a Merc Opti - but then I have the 20" transom and original floor height, so motor weight would also be a concern to me. With the mods you're doing, 25" tranny, raising the floor, you won't have those concerns. Given that, a Suzy 140 fourstroke might be a real good choice, also.

On the flip side, there are those who think a 150 minimum is needed for these 20's - I just can't see that, given how mine runs with an old 115.

If I might ask, what hp was the old 77 Johnny you took off, that you thought was more than needed ? Some folks have put up to 225's on these boats - older, lighter two strokes, that would be a screamin machine... on a lake!!

All boils down to you, your preferences, need for speed, intended use, etc.

Bill

Re: 1969 20' engine choice
 

E-S-D - just a follow-up to your train of thought - I don't know when they changed the outboard motor hp ratings from measured at the powerhead, to at the prop, I'm thinking sometime after the 70's ?? but from what I think I know on that, wouldn't an older rating 150 be about equal to a new rating 130 - 135 ?

On the bogging, not uncommon on older, carbureted 2 strokes, mine bogs initially when coming off a prolonged low speed troll, till it clears out - don't have any injection motor experience, but I would suspect that more accurate fuel metering would help that greatly - two stroke carbs are notoriously hard to dial in for both mid range and top end, whether bike or ob, get too lean and you cook the motor, leave it fat for motor life sake, and live with the bog, unless you're racin, in which case you know your pushin the limits and in for constant tear down and rebuild anyways.

just some stray thoughts

Bill

Re: 1969 20' engine choice
 

More stray thoughts. Part I's '87 18 originally powered by a V-4 Johnson 112/115, slightly underpowered, in his opinion. Rebuilt V-6 Johnson 150, not sure of GPS WOT. Much happier.

My '79 20 MA originally powered by Merc. 200 BM blew up 1 hour after seatrial. Repowered 1999 V-6 carbed Johnson 175. ($600 for 200 HP carbs. (not necessary!)), not sure of GPS WOT. Much happier;)

The 20 is only minimally faster. Guestimatation: Both running very close to 50, light load, one occupant and trimmed. Both 15" transoms, and stock floor heights. Neither have T-top, trim tabs, or Porta- Potties. However, both do have fully stocked adult beverage coolers!

NOTE: We share a Jersey Speed Skiff, we guestimate closing in on 70 GPS, but thats unofficial as well. Stop down the LowCountry! Mike.

Re: 1969 20' engine choice
 

SC,
I have a 20' seafari myself with I/O, but two weeks ago I ran a clean 75 20' CC, with a very new 130 2-stroke yamaha. What a ROCKET!! full fuel, two people + dog, if you weren't holding on, you were going out the back. Based on the transome height, I would not put any more weight on the aft end of that boat even if the transom was 4-5" higher. I can't imagine 15 less hp would be a big production. The difference you will have between a 1977 outboard and a new one is going to be substantial. I do know somebody who is redoing a boat just like mine, raising the transom 5" adn plans on putting 115 2-stoke on it. 6 cylinders is too much weight, in my own opinion of course...

Re: 1969 20' engine choice
 

200 hundred ponies on the back of NoBones is nice to have
when those famous afternoon storms sneak up on us in Florida. The weight is not that big of an issue with a raised transom and deck. Plus the fact that when you are
loaded up with gear and people the fuel consumption is far
less with more HP. You do not have to stuff the throttle
with a load. I have been in 20's with 90HP to 225HP
I'll take the 175-200HP range any day.
See ya, Ken

Re: 1969 20' engine choice
 

I have been thinking about this same question for some time now, and this is what I came up with...

Alot of people here have suzuki 140's on their 20's, but the suzuki 140 is closer to a 115 b/c it used the same block.
The evinrude etec 115 i'd say would have about the same power as the suzuki 140. believe the prices of the two would be similar also.
I don't know anything about the merc opti's, but i have heard good things.
My personal engine of choice i think would be a honda 135. The 135 is based on the block of the 150 and is still only a four cylender, so your get the fuel efficiency of a smaller engine, but the power of a bigger one....

Ok..enough rambling. This is just my 2 cents.

Re: 1969 20' engine choice
 

Some things to look at when deciding on an engine size that are not usually brought up, are gearcase size and overall weight.

Some smaller block motors share the same gearcase size with their larger cousins, but with a numerically higher ratio. This lets them use the same props, but puts the RPM range significantly higher for an equivalent speed. This can make the predicted fuel savings of the smaller motor dissappear.

Other times, the smaller HP motor is on the same block as it's larger cousins, and so weighs the same, just has less power.

Best overall results usually come with the most power in a given sized block selection. That configuration has everything working in it's most efficient combination.

I have an 18SF with an Eagle series (60 degree V6 block) Ocean Pro 150. It's nice in that it's about 75# lighter than the 90 degree V6 blocks (200 and 225 hp). It runs low 40's (wot) on GPS and has it's sweet spot around 3000rpm.

I can't imagine putting any less power on a boat any bigger.



Darlene

Re: 1969 20' engine choice
 

If it were me . . . I'd look at a 115/140 suzuki or a 150/175 suzuki.

Re: 1969 20' engine choice
 

Wow! thanks for all the comments. I am a little stuck on e-tecs now but can be persuaded. The 115 is a v-4 and weighs 375#. The 150 is a v-6 and weighs 427#. The Suzuki posted weights have confused me and cause me to doubt. The 115 seems to weigh 427 but they list the 140 at 410 or 420. How can that be? I wouldn't consider a 115 4-stroke (getting on plane a worry) but may go with the 115 etec. It is also about $3000 cheaper than the 150 e-tec. As to the old engine, it was a 175 Johnson. I'm gonna do some research on its weight. With the low transom, the waterline was only a couple inches below the splashwell docked. That old carb engine stalled bad but cruised great. It had no pee hole but did have temp guage and pushed H2O out of two exhaust ports just below the engine. My mechanic said those ports were supposed to be a couple inches out of the water or the carbs loaded up. With mine, they were under H2O when trolling but trimming up the motor when trolling so that they were out of the H20 helped with loading up and stalling. My conclusion is that the old Johnson was too heavy for the boat making it very stern heavy when trolling. I am aware that more power gets you on plane quicker and is usually more efficient when carrying a load or working against a sloppy ocean. But my thinking is that a boat that is less stern heavy will actually troll better and more efficiently - which I do often. Am I right or wrong? It seems that Seacrafts are designed to be stern heavy but what is the limit? In other words, what would Moseley or Potter say about moving weight forward (console, battery, livewell) to offset heavier engine? Wouldn't that change the ride considerably from the way it was designed? Thanks for the link to the motor source. Will check it out.

Re: 1969 20' engine choice
 

To my knowledge the 140 Suzuki weighs less than the 115 because it is the same block as the 115 bored for larger pistons (less engine block weight).

I have the 140 and could not be happier....JW

Re: 1969 20' engine choice
 

That makes sense, esp if the difference is just 7 lbs. The larger pistons would not weigh as much more as what is bored out of the block - all else being equal. Haven't completely ruled out the Suzuki. Had a 15 that was great and never gave me any trouble.

BTW, the old Johnson 175 I took off weighed 385#'s, according to the manual.

Re: 1969 20' engine choice
 

115 and 140 have different trim systems, gear ratios, etc. Maybe those small differences add up and account for the difference in weight.

Re: 1969 20' engine choice
 

My 20 MA has a 200 Merc listed at 406 and a standard transom, but has both batteries under the front of the console that would be a must. My livewell is built into the transom and can't be moved, not sure what set up you have. Tough call on this one, maybe the 150 and you go on the Atkins diet [img]/forum/images/graemlins/tongue.gif[/img] not sure how much you would notice 35# though.

Re: 1969 20' engine choice
 

If you are raising the deck 3", you can more or less look at whatever engine you want (within reason). The deck in mine was raised 2.5" and I have a 75 gallon tank along with a Suzy 140 and everything is fine (no splashwell, no plugs in scuppers, etc).

Re: 1969 20' engine choice
 

I've got a 115 suzuki on my seafari. She runs great, great planing speed, great troller. Tops out at 38mph on gps. 28 cruise. Would love a 140 suzuki. Seafari a little heavier than a cc i'd think it would go great!!!! Good Luck!!!http://i151.photobucket.com/albums/s.../seacraft2.jpg

Re: 1969 20' engine choice
 

Finestkind - a lite blue Seafari on Cape Cod ? - was that you I saw last summer, mid July, outside of Barnstable harbor ? I was trolling in the red Seafari -

Interesting that you have a 115 suzi and get 38 mph gps - well above mine - what pitch / dia. prop are you able to run with that ?

ps - I'm also watching the ultimate Seafari thread with interest - I have a hard time believing that that's not too much top for that boat.

Bill

Re: 1969 20' engine choice
 

I run an E-Tec 175 on my 1976 MA CC and am quite pleased with the engine. I am on plane very quickly and have recorded a top speed of 51 mph at 5350 rpm on the gps. That being said I am sure that the 115 would do a good job as well. With the Florida rain storms I like to be able to get in quickly. With a 21" prop I cruise at around 3500 rpms at about 32 mph.

Re: 1969 20' engine choice
 

I haven't made up my mind completely but I think I may be leaning toward the 150 now. Over the 45 years I've been around boats, I have rarely heard anyone really unhappy about being overpowered but a lot of people are unhappy about being underpowered!

Re: 1969 20' engine choice
 

I once rigged for her owner a 20' CC, installing a 20" Merc 225 on a mechanical jackplate, with a low water pickup & nosecone. Cruised in the intercoastal at about 3800 rpm at 45 mph. Top speed was 62 mph at 6000 rpm running a 32" overhub chopper style prop.
The real story here? It was owned by 24 yr. old female attorney from Palm Beach who was given the boat by her Dad as a present for passing the bar exam.
It was fun to watch her flying down the waterway at 60 mph in a SeaCraft with a huge rooster tail behind her.

Do you need that much power? No, of course not. Sure is fun, though. :D

Re: 1969 20' engine choice
 

I think that would be a excellent choice, especially since I read the numbers above from the 175 ETEC, those are great #'s and I have a 200 Merc. Go to www.usavemarine.com and ask about the 150 ETEC, he is a big dealer and can ship it and give phone support if needed, might save some dollars but not sure where you are.

Re: 1969 20' engine choice
 

Yea bill I'm not sure what pitch or prop size it has but I do need to find out because I ran a ground out at billingsgate at 9:30 at night(ouch)!!!!! Had to sleep the tide out and finally got off around midnight!!! LOLOL oh well Live and learn!!!!! The poor stainless prop didn't look so hot after that so I have to get a new one for this season!!! And yes I am too also watching the ultimate seafari! I think it's great the kid thinks like me!! Yes I do think it's a little high but hell only one way to find out!!! I myself am hoping ot make or get a hard top made for my boat I don't want it to high just high enough for me to stand up. I'm short so I only need it around 5'10. Once I have that then I can get up on top and see how it is!!! But I wish him luck with his creation !!!! I think it looks great (not to fond of the flat steering wheel though it doesn't look to cumphy)

Re: 1969 20' engine choice
 

They can fix your prop finestkind no problem, you don't need a new one

Re: 1969 20' engine choice
 

Bill I told you that I didn't know the pitch prop I was running on my 115 suzuki. Well I found a guy that fixs props in Marston Mills, Cape Cod. When I took the prop off there was a 16 on the inside so I think it is a 16 pitch and I measured from the far outside of a blade across to the other and it was 12". So thats all I know about that I was just happy find the guy right near my house that fixes props!!!

Re: 1969 20' engine choice
 

Thanks EggSuckingDog!!! I looked around and found someone 10 minutes from my house that fixes props!! So I thank you or else I probally wouldn't have looked to get it fixed. Probally wouldn't have bought a stainless one either! So soon enough I will have my stainless back!! I call it my East Sandwich Beach Prop!! Thanks again!!

Re: 1969 20' engine choice
 

Is this a DF-115? They are designed to swing 14in dia prop's. If it's a factory Suzzy prop it will be a 14in dia. prop.

If it's a aftermarket prop, all bet's are off. The aftermarket guy's want to put smaller dia. prop's on them. :(

If it os a factory prop do NOT trust the marking's for the pitch.

Suzuki's always run less than they are marked. Don't ask me why. I don't know?

They can be as much as 2in of pitch less than what is stamped on the prop.

Alway's have your prop's check by a reputable shop before you make a change. You must know where you are, before you can know which way to go.
I use a shop that computer scan's the prop's. It's doesn't lie.

I have now had 4 Suzuki prop's checked and reworked.

The one's from last week that I bought were
2- Suzuki 14 X 20's RH & LH.

RH measured 19.1 pitch.
LH measured 18.7 pitch

They are now both 20 pitch.


The first one's I had were 14 X 18's RH & LH
RH measured 17 pitch
LH measured 16.7 pitch

They were both reworked to 18.5 pitch.

Re: 1969 20' engine choice
 

Hey Warthog ... or anyone else -

Can you tell me what the expected result might be, of switching from an aluminum prop, to a SS, of the same pitch / diameter ?

Also, any general thoughts on the following - my old '83 115 Johnny shows 8000+ rpm on the tach, at WOT, but I don't believe that, or it would have blown up - but I also show, on my Humminbird FF, which tracks voltage, that my motor's charging system is putting out something like 16.5Vdc - which is seemingly way high, and I'm thinking the high voltage output is giving me a false tach reading... and without a true tach reading, trying to fathom the mysteries of correct propping is kind of pointless -

any thoughts, observations, clues to correction ?

just a note, from a long history of dabbling in motor performance, especially including 2 stroke motors, I pretty much know that rpm and power output are directly related to designed in breathing capability, volumetric efficiency, breathing thru the ports - that's why Im pretty sure this thing ain't pulling cleanly all the way up to 8000+... by design it would run out of breath and choke before then - two strokes usually go flat, in power output, once they go beyond their designed breathing/power point (so do 4 strokes, for that matter)and it hasn't blown up, not that I ever hold it at WOT, but have certainly cruised at well over 6000 rpm, with plenty of throttle left, so, that's were I'm coming from that my tach is bogus, and thus my ability to judge correct propping ???????????

all thoughts welcome !!

thanks
Bill

Re: 1969 20' engine choice
 

First you need to have the voltaged checked out,thats way too high, that will cook the battery's early. I agree its not going 8K, there are different settings on them, maybe your is on the wrong one say for a 6 cyl.motor. I believe there is a regulator on those rudes and it may be possible to do it yourself, I can't imagine it being too hard. If you feel adventurous to DIY, go to this site for the part www.usavemarine.com, now I'm not sure if you can, so I'll give you a phone number ask for Mike- tell him where you came from- and he'll help 727 938 9796- actually ask him about the tach too while your at it.

Re: 1969 20' engine choice
 

The tach should have a switch for the number of poles your alternator has. Ask a dealer what the setting for your tach should be. The voltage should not affect your RPM readings, as they're based on the number of times your power pack is fired or the number of times the trigger on your stator is activated.

Re: 1969 20' engine choice
 

Frank can he do the rectifier himself? I've never had to do one or adjust the tach, thats why I said to call Mike about the rec and the tach, it just can't be too hard once somebody tells you where it is and it should be just change wires????

Finestkind: thats why you buy the SS, they can be fixed almost everytime, I know you guys have some rocks up there that could render one unfixable but the alum's are shot everytime.

Boy we really derailed Sonny's thread here :D

Re: 1969 20' engine choice
 

The back of the tach should have a small rotary switch witch can be moved with a small standard/flat screwdriver to the appropriately marked number of alternator poles. My Merc, with a teleflex tach uses the 6 pole setting. Of course, you can also try the different settings and see which one seems right. It probably won't hurt the tach, it just won't read right.

Re: 1969 20' engine choice
 

You are wise to pay attention to weight! As much work as you're doing to that boat, have you considered adding a good bracket like the Potter/Seamark deal to offset the weight of a heavy motor?

I ran a 1975 115 Evinrude (~90 HP at prop) on a 20' SeaFari for over 30 years, much of it offshore, including 6 trips from S. Fla. to Green Turtle Cay in the Abacos (Bahamas), a distance of ~160 nm one way. Power was adequate because it's only a 300 lb motor, so boat was well balanced and rode great. Cruised @ 4500 rpm/22-23 mph with very heavy load in 2-3' head seas or the 2' square waves (2' high, 2'apart) common to Little Bahama Bank; could plane at 12-13 mph/3000 rpm using trim tabs and full downtrim on motor and ride comfortably (sitting down!) in 4-5' head seas! Had zero durability problems; only complaint was fuel mileage (2.0-2.8 mpg). Last March I added a Seamark fg bracket and repowered with a 150 E-Tec; it's an awesome motor but way more power than this boat needs! Will run 50 mph but will start to chine-walk at that point; best cruise is 2700-2800/25-27mph/5.2-5.4 mpg! (Based on I-command tach & GPS spedo) I considered the 115 and would have probably bought it instead but they didn't start production till June 06. Evinrude is really sandbagging on the E-Tec hp ratings(NABM requires ratings to be within 10% of measurements); their 06 brochure contains hp/torque vs rpm plots for the "225" V-6 that shows peak hp at 240, so I suspect the "150" is at least 160-165, and the "115" is probably a 125, or 35 more prop hp than I was satisfied with for 30+ years!

I also considered a 140 Johnzuki (similar wt to 150 E-Tec)but it's fairly small displacement and I felt it might be a little weak on mid-range torque, which is important for running in heavy seas. The newer 4-strokes have more cubes but are also much heavier, so I wouldn't consider them w/o flotation bracket.
I'm a mechanical engineer and spent several months reviewing
engine options, so call me some evening at 561-622-7670 and we can talk and trade e-mails.

Re: 1969 20' engine choice
 

Thanks for the info DKB. Thats good stuff. I'm in the middle of a restoration project on a 20' sf. If I had the cash I would probably spring for the 175 suzuki but I think it may be a tad heavy for my 25" notched transom. When the time comes to make a purchase I might get a 130 yamaha 2S (If I can find a good used one). Seems to be a good match.