My V-20 performance

[chrisrub]

Hi all,

I'm new to the forum. I inherited a 1985 V-20 (pics coming) with an OMC sea drive 1.6 liter outboard engine. It's all stock from what I can tell. I've been using the boat for about a year and have a few questions.

What performance should I expect with this hull/motor combination, as far as mpg, cruising and top end speed, etc?

From what I gather, I'm getting about 1 to 1.5mpg. To get the boat cruising on plane at a decent speed I have to have the rpms at 4500. WOT is 5000 rpms. Top speed I figure is around 25mph

I don't have money to put into a new motor, so are there any things I can do to maybe slightly improve my numbers?

Thanks!

[macojoe]

Sounds to me like she is propped wrong?? thats sounds alright for cruz speed but top end should be better then that, and my V with a 175 outboard was getting 2 1/2 mpg.
What is the prop you have on there?? Most run a 17 pitch, I use to run a 15x15 1/4 on mine, got out the hole fast but lost a bit on the top end.

[chrisrub]

I have to be honest I don't know much about props. The one that is on there came on the engine when my grandfather bought the boat from the original owner. It has never been replaced or worked on as far he and I know.

[macojoe]

There should be a number on it someplace, either on the prop or in the center were the nut is, find that and go from there

[cterrebonne]

yep right behind the nut and washer, you probabaly could see it without removing those items. it will say somthing to the effect of this 13 7/8 x 17 the last to digits are your pitch.

[THEFERMANATOR]

15 pitch stainless will be your best bet for that boat. You have the same basic combo as my V and I topped out close to 30, and cruised around 20-22 turning 4200-4400 RPM's. My max RPM's were 5300. Milage on that boat is actually not very good as it is underpowered pretty badly. That 115 is working it's tail off to push that boat. Mine burned 32 gallons in just over 2 hours of running, so 1.5 miles to the gallon is about all it will get. Unfortunately your best option is to repower as there isn't alot you can do to that 1.6L to make alot more HP. You could swap over to a bubble back exhaust and go to the bigger carbs, but it still would only get you a few more HP and use ALOT more fuel. At least you already have the right boat to start a bracket project with. Where are you located at?

[chrisrub]

I'm located on Long Island, NY.

I figured the answer would be that it is severely underpowered. It just doesn't seem like enough HP to push the boat and be fuel efficient.

I've thought about getting a bracket and starting a project, but that may be down the road a little bit for me..

Thanks for the replies

[THEFERMANATOR]

If the SEA-DRIVE portion is still good, you could swap out a larger OMC onto the SEA-DRIVE assembly. This isn't an easy option as most of the time the bolts are coroded into place to the point there is no hope of getting them out. If you could though, you could swap a 200 or 225 over to your assembly. Although you would probably need to beef the transom a bit as a 225 SEA-DRIVE assembly is HEAVY!

[spareparts]

Ferm, what about the 140 Seadrive, could you swap a V4 looper on to the existing bracket?

[shaneburris74]

Alright I did a little math (with some help).....1.6 litres comes out to 96 cubic inches. With my limited knowledge on HP vs. CI, I'm thinking that the max HP that you could or would want to get out of a 1.6 litre would be about 115hp....yall agree with that theory?
That being said, would Wellcraft hang a ~115hp motor on a V? I thought they came from the factory with 150's or 200's????

[THEFERMANATOR]

Alright I did a little math (with some help).....1.6 litres comes out to 96 cubic inches. With my limited knowledge on HP vs. CI, I'm thinking that the max HP that you could or would want to get out of a 1.6 litre would be about 115hp....yall agree with that theory?
That being said, would Wellcraft hang a ~115hp motor on a V? I thought they came from the factory with 150's or 200's????


The 1.6L SEA-DRIVE was a factory option, I have one sitting outside. Yes it was only a 115HP flywheel rated engine, roughly equivelant to a 100HP engine today as we now rate at the prop. You could find a 140 SEA-DRIVE assembly as they do pop-up from time to time and swap it over to it. Or you could find a 25" shafted 150 or 175 cross-flow(there a bit thirsty still, but light weight compared to a looper) and take it loose from it's mounts and swap the powerhead, mid and lower as an assembly over to your SEA-DRIVE set-up.

Since you're in the great white north, that most likely means your boating season is coming to an end right now. I would sit back and watch craigslist and ebay for a used bracket and a used outboard. With the way things are going right now you could find a bracket and outboard in good condition for under $2K and just re-power it. Also watch that SEA-DRIVE assembly. If something breaks on it you would be money ahead to re-power it. Parts for the SEA-DRIVES are almost impossible to find when you need them, cost an arm and a leg, and will most likely not be in much better condition than your broken parts. You have to remember that the newest of the SEA-DRIVES out there areabout 20 years old. And these things were put on boats that were meant to be run in saltwater. They are getting all used up for the most part unfortunately, and OMC has long since left the scene with any new parts.

[shaneburris74]

Thats interesting stuff to know that Wellcraft had a power option of a 100hp motor. Here I am worried that when I hang my 150hp on mine that I'm gonna be lacking in power. I know alot of guys on here run 150's but I still have that worry.

[reelapeelin]

Thats interesting stuff to know that Wellcraft had a power option of a 100hp motor. Here I am worried that when I hang my 150hp on mine that I'm gonna be lacking in power. I know alot of guys on here run 150's but I still have that worry.

I'm runnin' a 17P prop on my 150 and toppin' out just over 40 mph (GPS)...it's plenty of power, but just once I wanna punch a V-20 w 225 hangin on her tranny...Oooooeee:beer:

[shubey61]

Runnin a 200 johnnyrude w/a 15 x 17 prop, tops out at 5600 rpms 45.7 mph on gps

[chrisrub]

Thanks for all the responses.

How big of a project is it to do a bracket repower job?

What would be a good bracket/motor combination to keep an eye out for?

[macojoe]

You want a flotation bracket and anything from a 140 to 175 will be fine!

I did mine as a few others here, I use too run a 175 with great results! My 23 Sea Ox is also a old sea drive bracket conversion!

[reelapeelin]

Thanks for all the responses.

How big of a project is it to do a bracket repower job?

What would be a good bracket/motor combination to keep an eye out for?

One thing we've talked about here when converting to bracket/outboard is be sure to use a 25" shaft motor as a short-shaft has a tendency to flood the motor when trottling back to a stop...

Another consideration is motor weight and these days the E-Tech has 'em all beat in the power-to-weight ratio department...an Armstrong aluminum flotation bracket and an E-Tec 175-200 would be my choice

[jjjjasonab]

I have the 2.0 model sea drive and i hit 55 mph w/ 225hp via GPS in 1-2 foot seas. Its gotta be the prop. go to the prop shop and get a new higher p prop or buy my seadrive and motor and slap it on there and hold on, ill take 1500.00 for the whole drive and motor and its already off the boat, i had a bad transom. Jason 1-757-724-8686

[Hammerhead]

I have the 2.0 model sea drive and i hit 55 mph w/ 225hp via GPS in 1-2 foot seas. Its gotta be the prop. go to the prop shop and get a new higher p prop or buy my seadrive and motor and slap it on there and hold on, ill take 1500.00 for the whole drive and motor and its already off the boat, i had a bad transom. Jason 1-757-724-8686

WOW,....fo' real??? that's a deal. :clap:

(Chris,... look into this.)

[chrisrub]

I have the 2.0 model sea drive and i hit 55 mph w/ 225hp via GPS in 1-2 foot seas. Its gotta be the prop. go to the prop shop and get a new higher p prop or buy my seadrive and motor and slap it on there and hold on, ill take 1500.00 for the whole drive and motor and its already off the boat, i had a bad transom. Jason 1-757-724-8686


I will definitely keep that in mind if I decide to go that route. Right now I am looking at some other boats, but still haven't decided totally against a repower. Thanks for the offer!

[cterrebonne]

WOW,....fo' real??? that's a deal. :clap:

(Chris,... look into this.)

i'll back it up too, my 200 ficht was mounted too low and i was at 49.5 - 50 turing a 19" about 5600 or so i believe.

[chrisrub]

I'm sure it's a good deal, but by the time I get it shipped up here or run down there to virginia and pick it up I might lose the value there.. I'm not gonna rule it out just yet though

[Steplift 72']

The 1.6 litre is just under 100 cube's. 115 hp on a V-20 should get about 30 mph. A crossflow V-4 will drink the fuel if cruised at over 4000 rpm. I've had 2 OMC crossflow motors and found 3800 to be optimum cruise for mileage.

Have you checked compression, with a 15P prop it should turn well over 5000 if it's making the rated HP.

I've seen an early 70's V-20, lightly loaded, with an 85 Johnson make 28 at WOT.

My old V with a 135 hp crossflow Johnson ran mid 30's and got at least 2.5 mpg. The older V-20's were lightly equipped compared to the boats from the 80's and later.....how loaded down is your boat?

Your boat needs a 17P to get cruise speed in the proper rpm range, but doesn't have enough HP to turn it.

I tried a popular brand aftermarket prop on an 83' crossflow and it ran awful. We had to run an OMC prop, might have been an exhaust backpressure issue. What mfg prop are you using?

[chrisrub]

The 1.6 litre is just under 100 cube's. 115 hp on a V-20 should get about 30 mph. A crossflow V-4 will drink the fuel if cruised at over 4000 rpm. I've had 2 OMC crossflow motors and found 3800 to be optimum cruise for mileage.

Have you checked compression, with a 15P prop it should turn well over 5000 if it's making the rated HP.

I've seen an early 70's V-20, lightly loaded, with an 85 Johnson make 28 at WOT.

My old V with a 135 hp crossflow Johnson ran mid 30's and got at least 2.5 mpg. The older V-20's were lightly equipped compared to the boats from the 80's and later.....how loaded down is your boat?

Your boat needs a 17P to get cruise speed in the proper rpm range, but doesn't have enough HP to turn it.

I tried a popular brand aftermarket prop on an 83' crossflow and it ran awful. We had to run an OMC prop, might have been an exhaust backpressure issue. What mfg prop are you using?

Haven't yet checked compression. I'm not even sure of the prop mfg, as its never been changed/serviced since my grandfather bought it back in 94!

I usually carry a light load. It's usually just myself, sometimes another guy or two will come. I run about 1/4 tank of fuel most of the time as I don't go far. Typical trip (3 miles each way, plus drifting and moving for about 3 hours) will burn about 10-12 gallons of gas.

[THEFERMANATOR]

I have the same boat with a 1.6L SEADRIVE and it had a fresh rebuild on it. I was using a 15 pitch stainless prop and was turning 5300-5400 WOT with me and 2 dogs in the boat and 3/4 tank of fuel. The 1.6L is pretty underpowered for a V-20, and milage will suffer because of it. I had to run 4200 just to keep the boat on a plane with mine, and it sucked down 35 gallons in 2 1/2 hours of running during break-in(just before the transom delaminated). The 2.0L has ALOT more power potential to be had, but a repower with a bracket would make the most sense financially if you keep it.

[Steplift 72']

Something is really wrong with the fuel consumption you've quoted. I've had 8000 pound boats that used less fuel. My 248 Offshore with twin 140's would run a 30 miles on 32 gallons with smooth seas.

1.6 litre parts are cheap, if you can get the HP up maybe you can re-prop to cruise below 4000. As long as you're cruising at 4500 you can forget about mileage with that crossflow motor.

[reelapeelin]

Something is really wrong with the fuel consumption you've quoted. I've had 8000 pound boats that used less fuel. My 248 Offshore with twin 140's would run a 30 miles on 32 gallons with smooth seas.

1.6 litre parts are cheap, if you can get the HP up maybe you can re-prop to cruise below 4000. As long as you're cruising at 4500 you can forget about mileage with that crossflow motor.


You HAD a 248 OFFSHORE!?...lordy, what happened to it:head:

[Steplift 72']

I bought a 248 Offshore new in 1985 and powered it with twin 1986 Evinrude looper 140's. I ran it until 1994 and have since owned a few more including a Grady White 248 Offshore with twin 130 loopers. The Wellcraft 248 was the best boat I've owned, I had it 140 miles offshore once and typicall ran 80 to 100 mile out. It was so easy on fuel compared to the Grady White, it planed out nicely at 3500 and cruised economically up to 4300 which was getting close to 35 mph. I never installed trim tabs on the boat because it planed so flat at such a low speed. It had the best walkaround design I've seen since the front deck walkway turned outboard and drained over the side.It would really scream loaded lightly and it's embarrased a few bass boats and ski boats. I sold it to a car salesman that forgot to install the plug....he thinks. They're lucky to have survived. It went down in WC Block 110 about 18 miles south of Cameron, LA in the winter of 1995. They were picked up by a commercial boat minutes later. I saw a 248 project hull for sale at a marine salvage place somewhere around Atlanta. They also have a 21 Nova for $750! I always loved the look of the Nova. I belive the place might be called Lanier Marine Liquidators.