40hp too small?

[idsebby]

So did a quick search and can't find any relevant threads. Mby I didn't try hard enough?
I have a 5.2 Rimini rib debating a few things about what motor to go for.

The two motors I have currently are 92 40hp mariner and a 93 40hp Evinrude. I was going to put the Evinrude on my boat and just sell the mariner and buy a small aux.

But I started thinking that the 40 is probably too underpowered?

So my other idea is buy another 40hp mariner run twins and sell the Evinrude?

Basically I wanna know if it's a bad idea to just have a single 40? Because it would be much easier to just run the Evinrude.

Also looking at a 1990 Suzuki dt55 might spring for that? It's been sitting 5 years. I do most my own work so not to worried about replacing parts. I just want to have enough safe power don't really care about going real fast.

As you can see I am on a tight budget. I need to do things the cheap way but still be safe.

[idsebby]

Do I even have enough transom space for twins?

[Last Tango]

Hi

Generally speaking you need a minimum of around 50hp/ton to get a boat onto the plane so it's going to depend on what you want to do with it. Loaded with divers and their gear It's going to struggle.
With just a couple of adults you're probably looking at the right side of 20 knots.
If your budget's tight do you want to be feeding and maintaining two engines? (probably going to have to re-prop them to get the benefit.)
I'd try it with one of the 40hp & if that's not hacking it, sell them both and get something a bit bigger.......I'd have some reservations about the 26yr old Suzuki that's lain for five years, remember outboards seldom get the opportunity to wear out, they die of neglect and not being used

[treerat]

I'd be nervous about putting twins on a Rimini, my transom was suffering and that was with a single.

If it was me I'd sell the engines and add something in the 75 - 90 hp range, especially if loading with divers and people. Two of you pottering about a 50 would roll along ok.

[jonp]

Two 40's would give around the same performance as one 60 hp. Personaly I would be looking at a single 70 and sell the other two.

Jon

[idsebby]

Yeah I see all your points. I am also looking at a 2000 mariner 40hp he wants 870euro. Gonna sell my Evinrude and probably grab that. I am not gonna be diving off it cause I sold all my diving equipment ;(.

Mostly gonna be fishing with 4 guys.

I can get the dt55 for about 300 so it's still tempting. It was an old speed boat engine. Been in a garage for 5 years.

[Xk59D]

If it is 4 adults you better be looking to max out the hull rating hp wise or you will struggle to get on plane.

Hang tight and do not throw good money away, something will come along.

[berat]

If you dont need to ride at the maximum speed all the time you can get a smaller propeller. And by this time sell one of the 40s and wait for a good opportunities for max adviced hp

[idsebby]

Well I sold one 40 this afternoon. The other 40 I was looking at sold so gonna take a look at the dt55. Really need something under 900 so kinda on a tiny budget.
Anything over 100hp probably would be too much for that boat?
Sorry all this Hp rating stuff and boat size is pretty new to me.

[idsebby]

Originally Posted by berat

If you dont need to ride at the maximum speed all the time you can get a smaller propeller. And by this time sell one of the 40s and wait for a good opportunities for max adviced hp

What would a small prop do? More torque?

[berat]

More torque & easy plannig, but the maximum speed will be decreased. I remember my old 50hp johnson prop was 13-3/4 x 15 Aluminium, should be same with yours.

[idsebby]

https://www.donedeal.ie/view/1276611...e<br /> <br />

What ya guys think of this too big?

He wants 900 for it and that's the tip top of my budget.

Also about the smaller prop not a bad idea will look into that if I get a 50 or so.

[ashtonmarine]

Hi

I the link does not work for me but if it was my money I would:

Use the 40hp you have in the short term
Look for close to the max HP for the boat after checking the transom is solid
Trade up when you find the right outboard at the right price.

As a broker the thing that amazes me is when people rush. Buyers get the wrong boat and sellers if they rush dont get the boats value. This is the same for outboards. If you rush in it will be wrong in some way or you will miss something.

As for auxiliary. Having something to get you back and not need help is always the best way. Having said that I good anchor, VHF radio and flares also work for a lot of people. There is no right or wrong and for me its more about what you are happy with.

have fun

Dave

[idsebby]

Well long story short I ended up taking all your advice. Got a Suzuki
1991 DT 85. Its got good compression 120 122 117 lowest on the bottom. Been sitting on a pallet for two years, But started up right away. Oil injection has been removed. Has brand new prop. pumping water very very strongly. New thermostat. It needs the gear box water seal redone but the box is shifting fine. Also needs a block water float sensor it's causing a fault and going into limp mode. Three new carburetors have been fitted. All in all it needs some maintenance but he seems to have taken care of it. I know it's old but most the parts are new on it so should get a few seasons out of it. I got it for 525euros so if it blows up next week I can at least sell the prop controlls and tilt unit and cover my losses. Anybody had experience with these outboards.

[Xk59D]

yup, i had exactly the same engine.

the compression is bob on from memory and certainly bang on difference limits allowed.

i assume you mean a flow sensor which apparently is this (need serial number to be 100%)- http://www.suzukimotorcyclespares.co...e%20temp?uID=0

fixing the gearbox may prove difficult, what exactly is wrong? was it ever ran with water in there? new prop and water in gearbox says to me the prop was smacked and that could mean the shaft seals are the issue which potentially means the shaft is bent. i would put a dial gauge on it before you do anything just to be sure.

i have lost a gearbox before with water intrusion whilst at sea and it isn't fun nor cheap so please do your homework to avoid what happened to me.

[Xk59D]

some gearbox part diagrams here-

Fig. 26 - Transmission - Suzuki DT 85 Parts Listings - 1988 to 2000

Fig. 25 - Gear Case - Suzuki DT 85 Parts Listings - 1988 to 2000

once you get part numbers whack them into this for prices in UK-

Suzuki Spare Parts

[idsebby]

Gear box seems fine. Guessing / hoping it just needs some new seals been sitting a couple of years and was just run in a tub recently. The skeg was replaced 4 years ago and the gearbox inspected at that time. Someone backed the boat into a wall on a trailer broke the skeg off. Would it be horrible to test the engine for a few mins on the water with water in the oil?

[Last Tango]

It depends on what you mean by leaking? A few drops of water in new oil will not do any harm short term but if the oil is trickling out / water trickling in you'll wreck the gearbox pretty quickly.
Do a quick pressure test on it and see where and how badly it leaks.

[Xk59D]

hey buddy,

with all due respect it is too early to know if the gearbox is fine.

do not run it with water in it no, no good can come of it and depends on how bad the leak is how long it will last.

maybe it is just me but i don't buy that damage was done reversing into a wall myself so i would be checking it out properly.

a pressure test will ID the leak all going well but won't prove the shaft is okay.

the best thing to do is the pressure test and if okay dial gauge the shaft. there is a good chance it is okay but i'm thinking skeg, prop and it needs seals....ummmmm.......bent shaft is a possibility which is what normally ruins seals (as well as wear/tear).

if the gauge proves it is okay then you may still have issues stripping down 25 year old bolts depending on what seal/s are going. best case is it is the oil O ring which is literally pennies. it is dangerous to assume it is only that though given the circumstances for me and for minor checking you can rule it out for peace of mind.

[idsebby]

I get ya makes perfect sense. I did a quick test on the shaft to see if it was bent badly. Seemed fine I just held a flat head steady while moving the prop. There was no wobble in it but that's obviously just to see if their was major damage. Gear box shifted fine obviously there could be a hundred and one things wrong. Your man did not have a problem with me checking the oil and seemed genuinely shocked when it was the wrong color. I am pretty sure he had it on the water plenty of times after the skeg was fixed unless he was blatantly lying to me. He said he got it with a broken skeg.
I should probably just do an oil change and then run it for a bit and check for water yeah? How do you guys do leak down tests on the oil?