I/O vs VD settled. Hit a "log."

I have had both I went from a 2002 300 da stern drive to a 2009 350 da v drive 8.1 horizon now you will find that io owners love them and v drive owners talk handling gas milage is different if you keep cruising speeds the same for both sizes I also am in fresh water I Dropped my cruise speed from 30 mph @ 27gph when I was in 300 to 24 mph @ 26 to 28 gph instead of 30'mph@38 gph so you can slow down to min fuel as for maintenance io is more maintenance vs Vdrive log strike mine are mostly in tunnels so it would roll off maybe catch prop stern drive will bounce over catch prop so damage would be min on both iOS defiantly better in skinny water v drives are non forgiving but inall I prefer vdrives alot less high dollar components in. The water good luck with your decision
 
johngus said:
can't there be damage to the u joints for the drive after the high RPM while fully tilted?I would have the boat hauled,call your insurance and at the least have the drives pulled and engine alignment checked.I would also check the engine mounts at the stringers to ensure no damage.that was a hard impact and even though no seems no damage now,it may present its ugly face in the future.documant the incident now to protect yourself later..
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That is great advice. A report of the incident is in process. You never know what might happen down the road. The boat will be hauled and fully inspected at the end of the season.
 
This is a Volvo outdrive and I'm guessing they are also supposed to pop up on impact. I was in another boat when this happened and luckily we were there to tow them in and get it trailered. The boat was taking on a lot of water and both bilge pumps were on full blast. I think it was about $17k in damage altogether. If you lose your shaft on a inboard boat you only need to plug the hole (there are special emergency plugs made for just that).

This was due to hitting a log that was submerged a few inches under the water at about 35mph. The outdrive lower doesn't look bad but had fractures that made the drive unusable. I looked at the drive and couldn't see them but they were there apparently.


photo.jpg
 
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JV II said:
I would advise you to go with something that is fresh water cooled. A 2004 that is sea water cooled in salt water will have a significantly lower life.
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Here we go again with Salt vs. Fresh Water. I would take a salt water boat that has been used and maintained than a fresh water boat that hasn't moved all year and scarce maintenance. If a salt water boat is clean that means somebody has spent TIME on that bought to keep it that way. Long live salt water boaters!
 
LM230 said:
With an I/O, trim and swim, push the boat out of the hazard. This is probably only an issue with inland boating/smaller lakes etc, but I was a nervous wreck in unknown water with a V-drive, even with good depth equipment. JA
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Love the words "trim and swim." I wish I had known it earlier, I hit a submerged dumped concrete island this summer. I was going very slow, and stopped instantly. So far, so good. But, I could hear something banging as we bobbed in the water. I was scared it was the hull (wasn't), and wanted out. Now the bad part, I started the engine and tried to back out. Dinged up the prop just a little bit, and broke off the back inch or so of the skeg on a vertical line. Then, I tried trim and swim, and with just the trim up, I drifted back out of the hazard. Swimming would have been a hazard, but I carry two oars on board, and pushing back would have been a snap if needed.

My new second favorite maxim from this site after "Docking Speed Should Never Be Faster Then You Want to Hit Something" is "Never Power From Submerged Objects, Trim Up and Push Back."
 
I have a question - doesn't something "break" to allow the drives to pop up? I ran over the newspaper with my snowblower, broke the sacrificial shear pin so the auger stopped spinning. Much cheaper to put in a new pin, but it did have to be replaced. Do the drives have something like that?
 
I can't see how you would use $3750 more in gas at 50 hours. I don't spend that in a season on fuel.
 
rondds said:
I have a question - doesn't something "break" to allow the drives to pop up? I ran over the newspaper with my snowblower, broke the sacrificial shear pin so the auger stopped spinning. Much cheaper to put in a new pin, but it did have to be replaced. Do the drives have something like that?
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I've hit two newpapers with my blower and never broke the shear pin. But, talk about a bad paper jam and a really bad state of mind and frozen hands.

In my Mercruiser manual, there is a a topic - Drive Unit Impact Protection -

Shortened Quote: "The power trim hydraulic system is designed to provide impact protection for the sterndrive unit.....etc. After clearing a hit object, the hydraulic system allows the sterndrive unit to return to its original operating position, preventing loss of steering control. No impact protection is provided in reverse." (As I've learned.)

Nothing addresses any sort of shear pin. I just carefully moved after hitting concrete in my case, and tested things out. It drove fine, mostly hurt pride and about $200 in cosmetic concerns. I've probably gone 20 hours since. Probably should have had it checked out, but will get the repairs done at season end.
 
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skolbe said:
I can't see how you would use $3750 more in gas at 50 hours. I don't spend that in a season on fuel.
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That sounds right. My calculations, though correct, are based on the unrealistic operation of the boat at its cruising speed for the entire 50 hours. In reality, there is a lot of lower consumption trolling around at no wake speeds. Unfortunately for my wallet, I am a destination boater. Not much trolling goes on when I'm at the helm.
 
ZZ13 said:
That sounds right. My calculations, though correct, are based on the unrealistic operation of the boat at its cruising speed for the entire 50 hours. In reality, there is a lot of lower consumption trolling around at no wake speeds. Unfortunately for my wallet, I am a destination boater. Not much trolling goes on when I'm at the helm.
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50 hours at 30 gal/hr. and $5 gas will cost you $7,500. Not sure how you are calculating almost half the amount of fuel???
 
ZZ13 said:
I think that is sound advice. Does anyone know if there is any statistical analysis on this anywhere based on actual lifes of comparable engines in the two environments? I'd like to try tofind what "significant" means based on facts. Problem I have with v-drives is the size of the boat needed to get them. We really don't need any more space than a 300 provides. I did some math and for a 50 hour season, it will cost $3750 more in fuel to go the same distance in the V-drive 320 that one could go in the stern drive 300 (based on mpg at each boats optimun cruising speed). There's a lot of maintenance (if done yourself) that can be done for those $3750 a year. That gap increases as fuel prices increase.

The 2004 300 is a fresh water boat its whole life and will stay in fresh water for 3 more years. At that point another decision looms. Might decide I don't like cruisers and their annual costs, and then go to a deck boat.
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I agree with Skolbe. There is no way on God's Green Earth that you could use $3,750 more fuel in a 320 with V drives compared with a 300 with I/Os. Your Engineer spouse must have been using a slide rule and misplaced the decimal point!:smt101. A 300 is only 2 feet shorter in length and 1 foot less in beam and about a ton or so lighter. On plane at 3600 rpm my 320 uses about 26 gals per hour. Assume a 300 with I/Os would get at the absolute best 15%-20% better mileage which would be 4-5 gals X 50 hours x $5 or $1,000 to $1,250 more per year. Realistically the number would more likely be $500-$600 per season which is chump change compared to maintenance and purchase costs. The additional maintenance costs of I/O's over time would likely wipe out most of the fuel savings.

A 05 320 vs. a 04 300 would be $20K-$30K more based upon what I see on Yachtworld. At 5.5% interest, this is about $2K more year. Your decision should be based more on this difference than any potential fuel savings. If you plan to spend more time below decks than above, the extra cabin space of the 320 might be worth the extra cost. If you are like me and my wife, we have yet to spend a night on the boat which is one of the reasons I have it up for sale.

Finally, you mentioned above that you might move to salt water after a few years. If this is the case, very few fresh water boats will have closed cooling and to add it at a later date is not a trivial amount of money. I believe the previous owner of my boat spent $10K-$15K to have the dealer convert it to closed cooling because he thought he was going to move the boat in the winter to his home in Naples and bring it back in the Spring to WI. He never took to the boat to FL so I have a fresh water boat with closed water cooling that has never touched salt water except some condensation off a salted rim margarita.:smt043
 
My boat on plane burns 24 gph. But I also idle around over half the time at 1600 rpm's at 5 gph. My fuel cost is about $3.80 a gallon. I probably go through 500 gallons a season. 750 gallons max. I just had my props redone and new bottom paint which has brought my fuel consumption down. My dock neighbor used to let me driver her 300 with 6.2 mpi's and Bravo III's. The boat was a blast to drive. But it was harder to dock. But it ran like a rocket ship. However it was less comfortable as a cocktail cruiser.
 
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i have run 70 hrs with a 12 gallon per hour over all thats 840 at 4.00 thats $3360.00
 
320Bob, the purchase price difference is what I am seeing while looking. They are a factor. Sorry to drag everyone down the fuel cost calculation rat hole - was just trying to make a point. My calcs were based on Boat Test's numbers at cruise speed. They had the 300 with screws at about 22 gph and 34mph and the 320 with V's at about 26 gph at 24mph. I used $4.50 per gallon for gas price and calculated how much more it would cost in fuel to go the same distance in the 320 at cruise speed as one could go in the 300 in 50 hours at cruise speed.
 
ZZ13, The difference in gas is nominal when considering the whole picture of your move up in size. If that's really a concern, keep the 175 Sport. Brian
 
Bridog said:
ZZ13, The difference in gas is nominal when considering the whole picture of your move up in size. If that's really a concern, keep the 175 Sport. Brian
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I never stated whether it was a concern or not or whether it was a major factor or not. I just presented an analysis of one piece of boat ownership and what I could do with that fuel difference costs. And I am keeping the 175 Sport, in addition to whatever cruiser I end up with.
 
thats over the whole season its a an overall average for the season no wake and running at 24 mph @26gph so its trawler and planing and no wake seasonal average fresh water lake running
 
It's always interesting to look at your overall consumption for the entire season. I always put the boat away with full tanks and keep track of all gas put into the boat during the season. Add up the total gallons consumed and divide by the engine hours. Even my fat-arse pig averages, for a season, anywhere from 13-18gph. I try to remember that as I'm looking at the floscans showing 16gph each engine at 3300rpm.
 
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