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Scott Pearson
05-02-2000, 04:51 PM
Ok everyone,
I am having a problem setting up my motor in my 1968 18 foot 2+3. Its a small block Merc. with an Alpha drive. I have 24 inches between the stringers and the mounts are 26 inches end to end. These are the mounts that have the adjustment bolt through them and they have a Pad type plate with 2 holes. They get mounted to a piece of angle iron which gets bolted to the inside of the stringers. I am open to sugestions here and could use the help. I was thinking on cutting the mounts and re drilling them so the through bold in moved closer to the motor mount itself. I do not want to cut the stringers.

Thanks (NJ) Scott

kevin
05-02-2000, 09:42 PM
SCOTT, CANT HELP YOU WITH THE MOUNT QUESTION BUT I WAS WONDERING HOW THE PROJECT IS GOING.

GEOO
05-03-2000, 05:15 AM
Scott,
My 18 came with a sb chevy with cut stringers. They ended up cracking. I reglassed new stringers and used cut down engine mounts. GEOO

seano
05-03-2000, 06:27 AM
Scott,

I had a smilar problem with my cigarette. The outside motor mounts ended up directly over the stringer. All I did was turn the "angle iron" around so it was facing out. I did, however have custom aluminum mounts made and also had enough space between the top of the stringer and the mount to get a nut on the motor mount bolts---hope this helps

Scott Pearson
05-03-2000, 08:00 AM
thanks for the info guys,Last night I took the mounts and cut them shorter then I re-drilled them in towards the motor. They fit perfect! Now I have to get the alignment tool so I know where to put the mounts to the stringer. It looks as though the mounts are going to sit about 21/2 - 3 inches from the top of the stringer. I have to notch a small amount out of the stringer to clear the alternator bracket.Thats even with raising the X dimension up an 1 inch. I will let you know how I make out. Kevin, thanks for asking, the project is coming out great. Im taking pictures of everything so I should have some good pictures to post soon.

Scott Pearson
05-03-2000, 08:04 AM
sorry...21/2 to 3 inches BELLOW the top of the stringer.

seano
05-03-2000, 08:14 AM
Being below the stringer will definitely be a problem--I raised the x-dimension also--it was a good thing i did. It sounds like you know what you're donig, but I'll ask anyway---have you adjusted the motor mount to it's exterm "up" position---I don't know it that will give you enough though...

Notching the stringer is dinitely a bad idea in terms of strenght. How about removein the "foot completely and havin a piece of aluminum fabricated ito a new "foot"---I have see this done.

PaulO
05-03-2000, 11:10 AM
Scott, Just finished my Merc Alpha. I cut the stringers down approx. 3" including the section for the alternator and the fuel filter. I then glassed and bolted an additional 1 1/2" Oak stringer to the original stringer to accomodate for the cut out (meatball engineering). That placed the mounts directly over the now thicker stringers. I then fabricated a steel bracket that bolted to the inside of the stringer and extended both inboard and outboard to accept any possible alignment. Installation was neat and so far, no stringer problems. I considered upping the x-dimension but decided against it because I could not find anyone who had done it (I was afraid of ventilation) and also becuase there is zero room up top. As it is, my hatch with factory scoop just clears the risers. Now that it is done, I don't think I would have wanted to change the x-dimension. You can easily approach a trim angle that creates ventilation. I wonder if the higher x-dimension would prohibit sufficient trim angle. Maybe that can be overcome with a cleaver type prop. Don't know. I would love to hear from someone who has done it.
PaulO

Forrest
05-03-2000, 02:00 PM
PaulO, in the future if you ever want to raise the X-dimension, you can do as GeneD and myself did and that was to find an Alpha One SS drive. Bolt that puppy on and you'll raise your X-dimension by 2-1/2 inches.
On my 16 the factory Mercruiser #1 drive was mounted about 1/2-inch high (meaning that the anti-cavitation plate was about 1/2" highe than the bottom of the boat). Now with the Alpha One SS my X-dimension is about 3-inches high and I don't get any ventialtion on take-off or at any speed for that matter. Also, GeneD doesn't have any vetilation problems with his Alpha One SS drive mounted on his 18 either.

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Forrest

PaulO
05-03-2000, 02:43 PM
Forrest, Assuming I could find one, how much do you think an SS should cost? What did you record as far as speed gains?
Paul

Scott Pearson
05-03-2000, 09:45 PM
Seano,
I did not cut the stringer except for the altanator itself. the motor sits down inbetween the stringers. I used alum. angle iron on the insides and through bolted them. the angle iron is 3X3 8 inches long and 1/4 thick. They sit about 3inches from the bottom of the stringers. I adjusted the mounts and the alignment tool slides in and out perfect. So I guess Im ok.

Thanks Scott

Scott Pearson
05-03-2000, 09:57 PM
Paul,
Sounds like we did the same things. I made a 3X3 1/4 thick by 8 inches long alum. angle iron and through bolted them through the stringers. The Angle sits about 3 inches from the bottom of the stringer. I had to also cut for the altanator. I adjusted the motor with the alignement tool and its perfect. Slides in and out no problem. As far as the X dimension, Phil McKay put his up 2 1/2 inches with a 1967 three hatch boat and he really didnt have a problem. It was an Alpha drive and he does a little over 70 MPH. Alpha SS drives are hard to find and parts are big bucks. I looked for a long time with no luck. Thanks again for the info! NJ Scott

seano
05-04-2000, 06:39 AM
Scott,


Sound slike you've got this thin licked...don't you just love boats? You should have seen how much fun it was adding thru hull exhaust to my cig. I wanted to keep the exhaust below the gunwale---what a chore! Anytime you try to do anything different from what the manufacturer intended, it turns into a nightmare because so many other things are affected. It is fun though---good luck with the Donzi---if you boat anywhere on eastern LI---keep an eye out--all white 28ss--2000 mag mpi w/bravo drives and custom alum fairing in place of original windshield(that's another nightmare which I'll share with anyone interested)

Scott Pearson
05-04-2000, 07:49 AM
Seano,
Tell me abou it! what a project! Im keeping the boat left hade steering, that should be a bitch in itself! Im sure I'll work it out. let me know about the windsheild project? Maybe I wont feel so bad.

seano
05-04-2000, 08:13 AM
First, I had to make a template of the deck. that was fun. I still have the original windsheild and gave that, along with the template to my custom fabricator guy(he's actually very good). The only problem is, he didn't follow the template and the faring did not sit flat on the deck---I thought I could pull it down by thru bolting it, but ended up separating the vertical piece from the horizontal piece---my fault, i should have just brought it back---but you should see the size of this thing---i needed a flatbed to transport it from the fabricator to the paintshop to rigging shop...anyway, i was able to fix it and get it bolted down.---more later...

Forrest
05-04-2000, 08:21 AM
Right PulO, that is assuming that you can find an Alpha SS. I recently saw one for sale at OffshoreOnlyDotCom (http://www.offshoreonly.com) for $2200. At this point, I can't tell you how much speed increase got by going to the SS since I only have four-hours of break-in time on the new engine. Also, this engine should have at least 100 more HP than the old, and for that reason, I'll never know where the speed increase came from. I will tell you this however, the boat handles MUCH better than it ever did before. I bet GeneD can give you a better idea on what sort of top-end to expect since he started with an regular Alpha One drive and later went to the Alpha SS drive.

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Forrest

GeneD
05-04-2000, 09:12 AM
Wow, I get to talk now!!!
Yea!
The SS, properly set up with the correct gearing and propeller for my boat, gave me about 10 extra MPH.
Believe it or not. I swear that was the outcome. I was in shock. The 10 over is compared to what the old Alpha One was putting out. The drive was doing me about 58 with my 305. I put the on SS when I got my 350 and lost speed. Finally went to Lake X and got it re-geared and re-propped and voila, speed.
I'll check with Lake X to see if there are any more SS drives to be had. (that will take some time though)
As for the motor mounts, yes, I had the same problem. (see the tech articles for "Donzi Restoration Complete". The story of my near nervous breakdown!)
What I decided to do was rebuild the stringers. I took some timbers (treated 2x8's) and attached them to the old stringers using all kinds of methods.
Then...I had to cut them down 5 inches!
The secret to this whole thing is to make sure that the stringers have 22 1/2 inch centers. Too bad you did this without consulting the crew, I have the motor jig sitting in my shop right now. Lending is cheap, freight. If you still need it, contact me. It fits into the gimbal and sets up your MM's perfectly, height and width and proper space from the transom plate.
I also have the transom jig for cutout of the drive.
FYI.
Good luck, it seems as if you have this all in hand anyway.

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GeneD
007
Melbourne, Florida

[This message has been edited by GeneD (edited 05-04-2000).]

Scott Pearson
05-04-2000, 04:11 PM
Gene,
Thanks for the info, I used the set-up tools you spoke of and they all worked out great. It looks like everything fits just fine.Now to find a good spot for the trim pump and bilge pump...any Ideas? Also need to cut holes for exhaust.

Forrest
05-04-2000, 04:35 PM
Mount the trim pump to the side starboard stringer. You will need to remove the floor-mount bracket and drill four 3/8" holes into the back of the bracket. Now use the holes you just drilled into the bracket as a template to drill the 3/8" holes through the stringer. Mount the pump as high as possible. Now, place four 3/8" SS bolts through the new holes you just drilled into the pump mounting-bracket. Next put the trim pump back on to the bracket. Finally mount the whole works on to the side of the stringer. You may need to space the bracket out for the stringer a bit. Four 1/2" SS nuts work great for spacers. Be sure to use some 5200 or something of the like on the bolts going through the stringers.

As for you bilge pump . . . good luck. The one in my 16 is mounted with 5200 in front of the engine since the cast-aluminum Mercruiser-inboard oil pan is only 2" inches from the bottom of the bilge where the original glassed-in wood for the bilge pump mount is located. The 5200 seems to be holding quite well. If you go this route, be sure to rough-up the bottom of the bilge-pump mount with some 60-grit sand paper and *totally* clean the mating surfaces.


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Forrest

GeneD
05-05-2000, 08:11 AM
Ahhh, the mounting of the old trim pump.
Tricky.
As Forrest and ScotB can attest, I found a rather useful method.
I built little shelves on either side of the engine, attached to the stringers. All glassed in and solid. You can stand on them. But then again, I have the three hatch and I CAN stand in my bilge. Not to blow my own horn or anything you know. But that worked out really fine. I wonder if I have pictures. Maybe there are some in the Registry?
The bilge pump I just screwed down to the little pad just in front of the drain plug opening. In my boat, there was just enough room for one of those little pump dudes. No auto float yet, I'll save that for phase II.

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GeneD
007
Melbourne, Florida

Scott Pearson
05-05-2000, 01:04 PM
Thanks guys! Some great ideas that will be a big help. I let you all know how it comes along.

(NJ) Scott

seano
05-05-2000, 01:48 PM
Hey gene,

did the same thing--glassed in a full length shelf on each side and put the batteries and trim pumps on them--I'll have to post some pics too---not to toot my own horn either, but I am actually proud of how the boat is turning out---hope to drop the port engine in this weekend---i haven't even seen my boat in more than 2 weeks---need to check into AA(Aronow...)Have a good weekend everyone.