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[67hat34c]

Good idea genesis only one problem Reverse Rotation motors. Starboard one is giving us a little trouble right now and it is the reverse engine. You are right removal should not be a huge issue, besides I have my buddy Scott, Boatsb.

Outboards on a 36, not enough torque to push it. you would need 3 of them not 2. Remember these are semi displacement hulls, your Wellcraft is full plaining deep v. what would 3 250 to 300's cost, 60k plus all the alterations, beef up transom and build motor mounts another 20k or more i bet. However making it an express and doing the outboards would be a cool experiment for someone who has everthing. Wonder if the outboards would cure the keel walk problem, tripple set would be real stable.

 

[Boatsb]

When you get the crate engines get new trannys too. 1.9 and 2.1 are revereses so you use standard rotation engines.

 

[thoward]

Is there a motor that will run in reverse rotation?

 

[Boatsb]

the cam is differant as may be some other parts but the reverse at the transmission fixes that ASAP. I believe most diesels do that too. I have seen older internationals that literalls swapped front for rear and changed the rotation that way.

 

[Genesis]

Detroits are available as reverse rotation but most other diesels are not - its done in the gear. Ditto for MOST gas engines (but again, not all!)

 

[Boatsb]

The transmission being reversable makes it easier to have 1 engine for either side. cuts inventory cost as there is one set of parts.....

 

[Trojan]

All that is required to reverse the engines is to change the cam. Older gas boats with velvet drives were all engine rotation changes.



BILL

 

[67hat34c]

that is right. it has a reverse cam with timing gears instead of a chain, also reverse starter. cant remember about the distributor gear but i think it is the same.

If and when we have to rebuild we will just rebuild the one that needs it, these are crusader model 350 which as most know has a much different block than what Mercruiser used. Mercruiser used a automotive 454 with 2 bolt mains. Crusader used an industial 454, not to be confused with a truck block, that has 4 bolt mains and i believe a little heavier casting, possibly other differences. Anyhow none of this is in the budget financialy or time wise, over spent both last year, have to cool it for a while. If we do top end and carburator and it turns out to be only part of the problem then we only wasted the money on gaskets as they would be done on a rebuild anyhow. The only problem is we are not getting 4400 rpms, only 3900. same props and bottom is clean except slime. We unfortunately did not keep very good performance records from when everthing was good, only memory and possibly a few notes, stupid me.

 

[Boatsb]

Try adding some high octane fuel and see if it helps. Boat gas is 89 octane and you may need more depending on the engine and how real the 89 is. Also are they pinging? If not they are probably not overprpped.

 

[67hat34c]

not over proped, they are the 3 blade props that were on it when we got it., have reconditoned one time due to bending one up then retired them when we decided to go to 4 blade set. bent those up so put the 3 back on.

Need to ck them out, run with deck open and listen, do compression ck and timing. plugs are new so not an issue, no points have pertronix ignition and the vacuum leak was fixed. Oil just changed 10w30. not running hot.

 

[Maynard Rupp]

Steve,

in 2002 we sold a 28' Carver powered by twin 305 GM gas Crusader engines. At cruising speed - just on plain - she got 1.15 miles to the gallon. In January of 2003 we took delivery of our 1988 40' DCMY with 3208 Cats. When we brought it up from Ft. Lauderdale we were floored to accomplish the exact same fuel comsumption - on plain - as the old Carver. Since fuel prices went through the roof all of our old gas burner freinds stay at the dock and watch with envy while we continue to cruise.

Oh, you forgot to mention plug wires

It must also be said that if you are getting good service from your 454s and the "package" suits your cruising needs I would be reluctant to make any expensive modifications.

There is no comparison to maintaience costs between Crusader 454s and any diesel. I own both and do all the maint. work. Just compare the 7 quart oil change with its $4.00 filter. I can buy a mile of plug wires for the cost of one injector replacement. Plug wires last forever anyway, usually one change between overhauls. From what the experts tell me, and what I see here and on YW, the average life of a high powered DD 6V-92 is about 1300 hours. A 454 Crusader will go twice that.
The real fact is the size of your boat should dictate whether you use gas or diesel engines. The fuel costs are almost the same.

 

[Maynard Rupp]

There's nothing particularly bad about gas engines.

Their limitations come from their torque and how their torque curve looks. At a certain size boat they just don't do it anymore.

I'd draw the line in the mid 30' range; a 32 is viable with gassers, and a 34 might be. Somewhere around 34-36 you get to the point where you need the torque of diesels if you expect reasonable engine life.

Karl, our '86 36C at something in the mid 20k weight range is just fine. Cruise at 16 knots @ 20 gph. Top at 24 knots. 0.9 to 1.1 ganllons/mile at 8 to 10 knots. Hatteras lists the weight for the boat at 28k regardless of engines. Of course those Crusader packages weigh a lot less than a DD 6-71 package. A full tank of gas also weighs 400 lbs. less also.Any larger boat than ours would need diesels for sure.

 

[67hat34c]

Maynard, this got stared on a thread on boat us, someone wanted to know about converting gas to diesel so i put in my .02 worth and got raked over the coals by 2 members, one who is an expert and one who is a poser.

My contention is that if you want to convert to save money you never will, if you have plenty of money and want to go faster at cruise , longer range etc. then convert, why not.

Go to that site and look at the thread and see the quality or lack of quality of the responses from the members. Have never see poor responses like that on Sams site.

 

[Genesis]

Karl, our '86 36C at something in the mid 20k weight range is just fine. Cruise at 16 knots @ 20 gph. Top at 24 knots. 0.9 to 1.1 ganllons/mile at 8 to 10 knots. Hatteras lists the weight for the boat at 28k regardless of engines. Of course those Crusader packages weigh a lot less than a DD 6-71 package. A full tank of gas also weighs 400 lbs. less also.Any larger boat than ours would need diesels for sure.

A 36 is right on the hairy edge of what works with gas engines. Much depends on how you use it - how heavily its loaded, how much range you need, your operating needs in terms of speed, etc.

16kts is too slow of a cruise for most people "on plane". An 18-20kt cruise is reasonable but will beat gas engines to death in that boat.

1 gpm at 10kts is about what you get with most larger diesel boats at displacement speeds as well.

I'm not knocking gas engines - among other things they're VASTLY quieter than diesels, especially old ones. 6-71s ain't quiet by any stretch of the imagination! They're incredibly cheap to maintain compared to diesels too.

Lots of people are scared of gas engines because gasoline can go "boom". They forget that according to USCG statistics, more boats are lost due to diesel fires than gasoline explosions. Why? Turbochargers, which present two severe risks not present with gas engines - direct fire (exhaust leak, lube failure, etc) and "grenading" (leading to fire.) Gasoline explosions can be avoided by using your nose before starting up - its the best fume detector ever invented, and its free.

Believe me, once you get diesel fuel lit, it burns really, really well.

 

[Boatsb]

Thats a good agument for naturals over turbos too. Never heard of a natutal catching fire. Has anyone else?

 

[67hat34c]

Genesis, my arguement regarding how well diesel fuel burns. the guy on Boat Us said it is easier to put out diesel fire than gas. Guess he has never seen raw diesel burning, I have and holy cow is it hot. once it gets going you are not going to get it out easily.

as far as noise, i think the cummins 330b's are quite with the right mufflers. now your detroits especially scotts 853's with dubious mufflers, forget it. I know when he starts his boat in merritt island because i can hear them from orlando. (60 miles away)

 

[Boatsb]

Loud pipes save lives.