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Re-power on a budget

Posted: Mon Sep 21, 2009 11:33 am
by Terry
My 40 year old Volvo diesels are in need of repairs and I've been warned about chasing parts for a 40 year Pugeot truck (what these engines were originally designed for). For one side, a water pump and pulley will be well over $1000.00 for parts alone!
I'm thinking or re-powering with either diesel or gas. Might or might not keep the same Volvo 250 drives as they are that old too.
Any thoughts, comments or advice?
Any leads on engines? What to avoid?

Oh yeah, the budget part..... I don't have one.

Re: Re-power on a budget

Posted: Tue Sep 22, 2009 7:54 am
by GOVAN
My dock mate has a 37' steel cruiser. Early 50's vintage, but, a very nice boat. He is a diesel mechanic. His gas engines are slowly fading and the steel gas tanks are rusting inside. He replaces fuel filters frequently. He intends to acquire diesel engines.

I thought that would be very expensive. However, he has discovered that school buses are retired long before the diesel engines need major work. He intends to acquire two school bus engines. Apparently there are many available to pick from.
He was offered one, whole, bus for $1000.00. He passed on that as he had no idea of how to dispose of a bus.

Brian - SIOUX

Re: Re-power on a budget

Posted: Tue Sep 22, 2009 11:03 am
by Terry
Hey David,
How big are your Volvo's and do you think these might be a good fit (I'll have to change to gasoline) and might these get me up on plane?

http://toronto.kijiji.ca/c-cars-vehicle ... Z127782999

Re: Re-power on a budget

Posted: Wed Sep 23, 2009 8:15 am
by Rob
Hi Terry,

David has 4.3 L V6s (about 230 HP each I think) which easily get Buster on plane.
I have the original straight 6 Volvo 170 HP engines which will not get Catherine Ann on plane . . . . but my boat is likelly 2000 lbs heavier than David's.
Cadoruca has lower HP 4.3 L V6s and planes easily as well, but is an even lighter boat than Buster.
You would not want to re-power and end up with "almost enough" power to get on plane.
I don't think that you would want to be under 220 with new engines . . . . maybe 250 original spec on used engines.

These are the best (US) prices that I have seen on new Volvo engines/outdrives http://www.marinepowerservice.com/Boati ... 450402.cfm

I would love to re-power as well . . . . . it's just that "no budget" thing that keeps getting in the way.

Rob

Re: Re-power on a budget

Posted: Wed Sep 23, 2009 9:27 am
by Terry
Thanks for the info Rob.
Getting up on plane is no big deal for us, I was just curious. I've got nowhere to be in that big a hurry and couldn't afford to play like that. We usually cruise around at 6 knots but wouldn't mind to get (efficiently) up to 8-10 knots if traveling with others. Could I assume that getting a bigger motor than I need, that it might work easier while traveling at lower speeds. (less fuel?)
Budget is my biggest hurdle and I'm looking for an easy way out.

Re: Re-power on a budget

Posted: Wed Sep 23, 2009 11:59 am
by Rob
Hi Terry,

I can't get past the "budget" part of re-powering either :)
The problem with buying used is that there is always a reason that the seller is repowering.
The engines/outdrive are worn out/abused/can't get parts/whatever.
Trying to mix and match different types of engines and outdrives can get complicated.
Creating a marine conversion to an auto/bus engine could definitely get complicated.

You could cut the repowering cost in half by going to a single engine.
A brand new V8 and outdrive might set you back $20K installed but would solve maintenance and reliability concerns for many years.
Add a bow thruster and you would actually have more docking control than with the twin engines.
Something to think about . . . . .

Rob

Re: Re-power on a budget

Posted: Fri Sep 25, 2009 7:13 am
by dpearson
Terry et al

Rob's response regarding Buster's engines is accurate. They are Volvo Penta 4.3GXi with SX legs. I don't think they have changed much from the $13K price I paid for the combo. Add up the labour and all the equipment that went along with the re-power and the budget will make you take a deep breath.

One point I would like to make is in reaction to the desire to be able to go 8-10 knots "efficiently". The Alcan hull speed calculates at 7.7 knots. Because they have a planing hull they can go faster, but it takes loads of horsepower. If you were happy at hull speed, you could probably use a 40HP outboard. If you want 10 knots, you probably need 120HP or more.

I sometimes think about the options for power, including the thought of putting in a single big V8. The modern 8.2l V-8 pumps out 420HP which is just a little bit shy of the 450HP in Buster. But with the single leg, it would have less resistance and might actually be faster. It would also be about 600lb lighter than the twin V-6's which would help the boat get up on plane. Then I watch the Poker run and I think "why stop at ONE big block?" and then my wife hits me.

Food for thought.
David

Re: Re-power on a budget

Posted: Fri Sep 25, 2009 7:54 am
by Terry
David,
You're the third guy to bring up the idea of outboards. One thought was to get rid of my swim platform and design a new one that would accommodate a couple of outboards. Probably the cheapest route and certainly the easiest one for maintenance. Don't know what it would look like but would likely take away from the "integrity" of the boat. I love the classic look of these boats and would hate to bastardize it too much.

A little lengthy for this forum, but here's some thoughts from a guy "in the know":

On Sep 15, 2009, at 8:44 AM, David H Wells wrote:

Hello Terry,
Nice looking boat.

Have you an idea of the weight of the vessel? Also what is the current draft? These will have a bearing on the positioning of the outboard motors and tankage if you decide to go that route.
On first thoughts, to keep the same draft (otherwise the boat will look like a drag racer with big tires at the back) you will need to add about the equiv ballast equal to the weight of the existing engines minus the weight of the outboards and bracket. You can add water and waste water tankage as well as adding a grey water tank. This will keep the on board water as a "static" weight factor.
Yes you can move or add batteries to your hearts content, but keep one dedicated for each outboard for starting purposes. The weight for the batteries and the distance from the center position longitudinally and laterally should be tracked.

Doing significant mods like this by yourself if a hit and miss game. It is not easy dealing with weight changes in a boat as it affects the trim, pitch and balance of the vessel. The PROPER way to do it of course is to have a Naval Architect involved to design the changes. He will design the weight distribution so you end up with a well balanced vessel in all respects. I have a couple I work with who I trust to do something like this properly, but they are not cheap.

The philosophy of suggesting outboards is that they are "modular" and inherently easier to deal with from a maintenance/storage and purchase point of view, but you will need counter rotating outboards if you are going to go this route properly.
The outboard mountings themselves are a no brainer as long as the brackets are the right height and they do not hang out too far at the aft end. If you need to keep the swim platform function this does add a little to the size and design scope. The engines should be as close into the transom as possible, so they do not get submerged in following seas. They should be far enough out so they can be tilted out of the water when not in use.
There are certain important anti-corrosion measures required when dealing with all modifications to marine engines and battery systems fitted to aluminum boats. These should be part of the main thinking from the beginning. Trying to deal with that stuff later is very technically and practically "difficult".

Fuel tankage is another issue we discussed. A NEW alcohol compatible fuel tank, or one for each engine would be the best way to go. If you use oil injected engines you will also need oil reservoir tanks, one per engine. The sixing of these tanks should be carefully calculated to match the quality of the gasoline tanks. This way you will not run out of oil before the gasoline is finished. It is best to have slightly larger oil tanks than the "mix ratio" required. This way you will run out of fuel first before you cook the engine by running out of oil first.

Other options are to replace the outdrive packages with a pair of newer, not necessary Volvo gasoline or Diesel outdrive packages. With aluminum it is easy to fill the outdrive hole with an aluminum plate welded in, then cut the new shape hole and instal a new or newer outdrive package. Singe the boat is already set up for outdrives this will involve less engineering changes, would not involve a Naval Architect or making an expensive bracket arrangement.

If you go for gasoline powered outdrives you will have to instal the whole engine space in full compliance for the ABYC (TP1332) recommendations for gasoline engine installations in boats. Even if you repower with diesels, or rework what you have, the requirements have changed over 40 years, and the installation will have to be upgraded to meet the existing requirements per TMS TP 1332 (Canadian Marine Safety mandatory requirements).

Before jumping to exclusions or conclusions lets meet at the boat and have a real look at what you have and try to sort out the most practical options. At the present time you have all options open to you. Once you start making decisions the options disappear one by one.

Sincerely

David H Wells AMS Y/SC.E
Accredited Marine Surveyor and Consultant



----- Original Message -----
From: Terry Robb
To: David H Wells
Sent: Wednesday, September 16, 2009 9:58 AM
Subject: Re: Alcan 370

Thanks for your input on my ordeal David.
I promised myself I wouldn't panic but am really leaning towards the two outboards solution. We'll haul out in Peterborough (Willowbend Marina) in a few weeks and arrange to meet there. If we go that route I might get lucking as Tom has the equipment and know how to strip the boat if need be. He might also be interested in some of the equipment and fuel.
Thanks again for your help and we'll touch base again soon.

--
Terry Robb
Mastercard III
http://www.alcanboats.com/mastercard_iii.htm

Hello Terry,
No need to panic. You have all the choices and all the options open at this point.
I was thinking we could keep an eye out for matched pairs of O/B's from boats involved in accidents where the vessel is trashed but the motors OK. Would prefer not to think about motors that have been sunk. Modern engines are much better fuel consumption than older engines although they are getting better. Four strokes are better still but somewhat limited in power because of their physical size getting almost as heavy as low power i/o's.
When looking for used motors some of the early OMC Ficht OB motors are quite problematic, and repeatedly so I have heard..Sometimes seizing up for no obvious reason due to improper oil/gas ratios. ALWAYS expensive to fix.
New motors are very expensive, even when purchased singly.

As mentioned there are "schools of thought" ref one large or two smaller engines. There are benefits to both sides of the argument. One engine is lighter than two, needs smaller fuel tank. Two have the reliability (redundancy) factor but cost more to buy and maintain etc..
For the reasons you mentioned two would be best on a boat of that size.

A motor bracket would best be attached to the edges of the transom sides and bottom. This way they are attached to strong points of the vessel.

Weight distribution will be an important consideration. Something you could do is move the generator as far back as possible if it is not already at the back. This will keep some "fixed" weight factor back there.

The prob with using "tankage" as "ballast"is that the weight diminishes as the water or fuel is used. This upsets the pitch and sometimes trim of the vessel. With the heavy diesels and only the fuel load the pitch change as you use fuel will be minimal.

By mounting the outboard as far back as practical will help this situation somewhat as the leverage will be best that way. All boats "turn" around a point determined by the weight distribution in the boat. A boat will turn on a point further back if there is a lot of weight in the back. If you take that weight out the turn point will move forward until the weighting factors are changed to bring it back.

The bottom line with this is that weight changes in a boat seriously affect trim, pitch and handling.

Yes, give me a call when the boat is hauled and we can meet there.

David


Re: Re-power on a budget

Posted: Fri Sep 25, 2009 11:08 pm
by dpearson
Terry

I didn't intentionally bring up the topic of outboards. I was trying to emphasize the inefficiency of boats at anything over hull speed. I did consider outboards when looking at re-powering Buster, but I/O seemed better given that that the engine compartment was already set up that way. It might be worth considering that outboards would leave a lot of room for fuel. If you removed the engines, you could probably carry enough fuel in the engine compartment for a tans-oceanic crossing. Nothing that credit cards can't solve

Re: Re-power on a budget

Posted: Thu Nov 12, 2009 11:36 am
by rambunctious
Around 2001 I owned a 37' Allwest with 17hp Volvo engines that were tired. I found a 27' Formula boat with 305ci chev engines and Volvo 280 outdrives.Purchased the whole boat for less than the estimated rebuild cost for one older 170hp engine. Removed older engines and replaced with these chev 305's. best thing I ever did with this boat. Ended up with props that were a little to big but with added trim tabs as well the boat would cruise at 20 knots @ 3000 rpm @ 1.2 NMPG.Installation was easy'the spacing for the engine mounts was the same and the cut out for the outdrives needed little changing.Boat ran very well when I sold it & the present owner is satisfied with it. On a separate note about re-engining,there is a 37 ' allwest in Sault st Marie Ont , the owner has removed the 170hp original engines and installed a 225hp Volvo single
DSL with 280 dupprop drive and claims 20 MPH cruise 25 MPH top speed. he changed the fuel tanks to a pair of 50 gal aluminum truck fuel tanks.This drops his fuel capacity but he's only turning 6 cylinders dsl instead of 12 cyl gas and with the added efficiency of the DSL should still maintainreasonable range.He also added DSL Genny and a bow thruster.

Re: Re-power on a budget

Posted: Thu Nov 12, 2009 11:37 am
by rambunctious
Around 2001 I owned a 37' Allwest with 17hp Volvo engines that were tired. I found a 27' Formula boat with 305ci chev engines and Volvo 280 outdrives.Purchased the whole boat for less than the estimated rebuild cost for one older 170hp engine. Removed older engines and replaced with these chev 305's. best thing I ever did with this boat. Ended up with props that were a little to big but with added trim tabs as well the boat would cruise at 20 knots @ 3000 rpm @ 1.2 NMPG.Installation was easy'the spacing for the engine mounts was the same and the cut out for the outdrives needed little changing.Boat ran very well when I sold it & the present owner is satisfied with it. On a separate note about re-engining,there is a 37 ' allwest in Sault st Marie Ont , the owner has removed the 170hp original engines and installed a 225hp Volvo single
DSL with 280 dupprop drive and claims 20 MPH cruise 25 MPH top speed. he changed the fuel tanks to a pair of 50 gal aluminum truck fuel tanks.This drops his fuel capacity but he's only turning 6 cylinders dsl instead of 12 cyl gas and with the added efficiency of the DSL should still maintainreasonable range.He also added DSL Genny and a bow thruster.