How to validate the condition of the wood inside the transom

BillaVista

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Re: How to validate the condition of the wood inside the transom

As to your original question of "How to validate the condition of the wood inside the transom", my recent experience tells me that without a good solid visual inspection, you cannot.

I did the jump on the anti-vent plate test, with an experienced hand to help me evaluate and all seemed solid.

Then this happened:

Starcraft-2013-Jul-07-5501.jpg


Lo and behold this is what was actually in there:

Starcraft-2013-Jul-15-5746.jpg


Starcraft-2013-Jul-15-5747.jpg


Starcraft-2013-Jul-15-5748.jpg


Starcraft-2013-Jul-15-5749.jpg


I think, when a boat is of a certain age, depending on how it was cared for (if you can even tell the complete history), you're almost better off assuming the transom is going to be wet / soft / rotten.
 

kungpaoshizi

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Re: How to validate the condition of the wood inside the transom

Wow that sucks Billa! Was that from the 79? That's what I'm afraid of, when I saw a '83 venture with that I started to wonder the realities...
 

kungpaoshizi

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Re: How to validate the condition of the wood inside the transom

Kung, OK you have a longshaft '76-'77 Merc Inline 6 motor, mounted on a bassboat that looks to have a 20" transom. The motor originally mounted with 2 hexhead thumbscrews and two 3/8" thrubolts. If you had the original PTT unit, there would be 4 more 3/8" thrubolts, in the PTT brackets. If the motor is mounted to the CMC unit with the two thumbscrews and two thru bolts, I would think it is fine. If you are just using the thumbscrews, you have a problem. However, I see the PTT brackets are bolted on. Without the PTT pistons, those brackets do not take the intended strain. Can you put a piece of angle iron between the lower shock mounts and the PTT brackets to hold the motor from tilting? That should restore it to as close to OEM as possible.

You're saying to do this Chris? Do I not need to attach the angle iron to the cmc plate? (or I need to flip it in this picture)
picture003.jpg

What do you mean by thumbscrews? The main 4 bolts from the motor to the cmc and upper adapter plate are 3/8" and I don't think I could do anything with my thumb.. :)

And you're saying any way you slice it I don't need to put anything in the top bolts because the PTT in inoperable? (I have no idea if it works, cmc came with boat)

I was wondering if I could remove or change the bracket on the motor out to better fit the cmc, but then again I was thinking of just replacing the transom with coosa board and get a jack plate.. :D (really am thinking about doing that)
 
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Chris1956

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Re: How to validate the condition of the wood inside the transom

I was suggesting that you replace the PTT cylinders (which you do not have), with a rigid piece of angle iron. That restores the strain of the motor to the PTT bracket, as the manufacturer intended. The motor would be placed against the tilt pin and the angle iron would be drilled to receive the bolts thru the PTT brackets (likely a 7/16" bolt) and the lower shock mounts (maybe an 11/16" or 3/4" bolt). Trust me, your PTT is inoperable without PTT cylinders.

The "Thumbscrews" I refer to are in the front of the transom bracket, screw thru the transom bracket and clamp the motor to the transom. They were not used after the mid 80s or so, but were replaced by all thru bolts.
 

kungpaoshizi

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Re: How to validate the condition of the wood inside the transom

I was suggesting that you replace the PTT cylinders (which you do not have), with a rigid piece of angle iron. That restores the strain of the motor to the PTT bracket, as the manufacturer intended. The motor would be placed against the tilt pin and the angle iron would be drilled to receive the bolts thru the PTT brackets (likely a 7/16" bolt) and the lower shock mounts (maybe an 11/16" or 3/4" bolt). Trust me, your PTT is inoperable without PTT cylinders.

The "Thumbscrews" I refer to are in the front of the transom bracket, screw thru the transom bracket and clamp the motor to the transom. They were not used after the mid 80s or so, but were replaced by all thru bolts.


This is what OEM would have looked like? Apologies, this is the first picture I've come across that isn't a CMC bracket lol..
Would it be worth finding cylinders and a motor to restore the original PTT? Since I've thought about a jackplate, I'm thinking it might be nice to have PTT still, and with restoring the original bracket configuration I really wouldn't be adding too much let alone I wouldn't have any more setback than the intended minus the jackplate, and that would satisfy the structural integrity of the mount?


Mercury_0792.jpg
 

smokeonthewater

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Re: How to validate the condition of the wood inside the transom

You COULD find the original cylinders and pump but it would likely be cheaper to just find a newer motor... you can search on ebay but those parts are rare and often, tho not always, expensive.
HONESTLY, your best bet would be to sell the motor and the cmc unit and pick up a short shaft engine that fits your hull and has modern single cylinder integral PTT
 

smokeonthewater

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Re: How to validate the condition of the wood inside the transom

BTW
Read "free boat" in my sig... I have first hand experience with an old merc, poorly attached to a CMC unit.... I came across a great deal on another merc with the complete factory PTT so I used it but I sold the CMC unit... it sold FAST on ebay btw
 

BillaVista

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Re: How to validate the condition of the wood inside the transom

Wow that sucks Billa! Was that from the 79? That's what I'm afraid of, when I saw a '83 venture with that I started to wonder the realities...

Yea, that's the '79. Looks dramatic but in the end, with the help of the great folks on this forum, I replaced the transom and deck and she's tight and solid now and ready for another 30+ years of service (all the details in the Resto thread in my sig block). Plus I know every inch of the boat inside and out now! Silver lining, I guess. Good luck with your boat.
 

Chris1956

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Re: How to validate the condition of the wood inside the transom

Yes, That is what the OEM PTT unit would look like. Of course the trim cylinders would be black instead of grey. Do you have PTT brackets like those, or are yours shorter?
 

Chris1956

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Re: How to validate the condition of the wood inside the transom

I just look at your picture again. Your PTT brackets are fine. Unless you attach the lower shock mount to the PTT bracket, that motor should kick up when you decelerate, or skip across waves.
 

kungpaoshizi

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Re: How to validate the condition of the wood inside the transom

I just look at your picture again. Your PTT brackets are fine. Unless you attach the lower shock mount to the PTT bracket, that motor should kick up when you decelerate, or skip across waves.


So you're saying just put something here?
Sorry I'm unsure if what I have circled is the lower shock mount or it's where the bottom of the oem PTT attaches to.

I'm just wanting to be sure I'm understanding this all correctly so my next lesson isn't "I should have done something about that engine mount!"
:)
I definitely want to use the motor though, short of a powerhead rebuild, new distributor, trigger, switchbox, and ignition coil, everything else has been updated/replaced minus the lower unit.
picture004.jpg
 
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Chris1956

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Re: How to validate the condition of the wood inside the transom

The lower shock mount is on the bottom of the Swivel Bracket. It will move out when the motor tilts. I think you should clamp it to the PTT brackets with a rigid rod, angle iron, strapping or something. The thing you have circled looks to be the part of the transom clamp that has the lower transom thru bolt. Make sure that is bolted to the CMC unit.
 

kungpaoshizi

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Re: How to validate the condition of the wood inside the transom

bottom%20bolts.jpg
So bottom of the transom clamp get bolted to the cmc unit, and the lower shock mount where the OEM PTT was, macguyver that to attach to the cmc unit as well. I circled both.. that about sums it up? I guess I'll have to goto Menards and pick through possible options..
Thanks very much for the help, I really had no idea it wasn't supported that well. I always thought it looked a little funny though...

Also Smoke, I did find the PTT trim cylinders and motor on ebay, bout 600$ for all before rebuild kits... Not sure how many motors you have around there, but the cheapest 115 hp motor I've found around where I live or on ebay is about 2-3k$... :)
 

Chris1956

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Re: How to validate the condition of the wood inside the transom

You must bolt the transom clamp to the CMC unit. Absolute must. If you need to put a plate of steel or something to bolt the motor to, and then bolt that plate to the CMC unit, that will work. Attaching the lower shock mounts to the PTT brackets, will keep the motor from flying up when you decellerate or hit something.
 

smokeonthewater

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Re: How to validate the condition of the wood inside the transom

YOU aren't looking hard enough..... This one is too big for ya but just what I found in 5 minutes of looking... Asking $1000... Prolly buy for $750 and MAYBE less, junk boat, costs $45 around here, sell trailer for $250, buy a prop for $50-$150 and you're into an outboard for $600-$700
16 foot 90hp Johnson

I bought my first 115 as boat motor and trailer for IIRC $140 and the second 115 the next day for IIRC $50
 

smokeonthewater

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Re: How to validate the condition of the wood inside the transom

OR here is the factory PTT AND what looks like a power jackplate! for $1000 (or less)
1985 addictor
 

kungpaoshizi

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Re: How to validate the condition of the wood inside the transom

But the thing is smoke, wouldn't I be in this same situation if I bought another cheap boat or motor?
That's the kicker..

ANY boat I could buy for that matter, or engine, very well could be just as lazily taken care of as any junk boat or engine, so ya, I would then have to 'fix it up' all over again. I'm not worried about the money, but working on this boat with the setup (that I like) is much more logical and productive than starting all over..

I mean heck, I might as well just spend 22k on a brand new boat and motor right?
But why do that when for 10k I can make this boat and motor into perfect condition and I'll know I won't have to touch it for years at least.

Lol, Idk, it comes down to the chicken or the egg right? But saying the motor is too tall for the boat is an embellishment, the PO ran it for 5-7 years as it sits right now, so I know it's not a catastrophic combination.
 
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kungpaoshizi

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Re: How to validate the condition of the wood inside the transom

You must bolt the transom clamp to the CMC unit. Absolute must. If you need to put a plate of steel or something to bolt the motor to, and then bolt that plate to the CMC unit, that will work. Attaching the lower shock mounts to the PTT brackets, will keep the motor from flying up when you decellerate or hit something.

Excellent, thanks very much Chris!
 

smokeonthewater

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Re: How to validate the condition of the wood inside the transom

noooo saying the motor is wrong for the boat is absolute truth... just because someone ran it doesn't change anything..... That said I have no intention of talking you into something you don't want to do... Just trying to make sure you know your options.... If you look at the second link.... you could end up with all of the good stuff on your current motor for very little money... sell youe cmc unit for a few hundred $ sell the boat and trailer for a few hundred $ put the jackplate and power trim on your boat.... have an extra powerhead and lower unit OR sell the left over motor without power trim.... Take all of the best parts and put your stuff together.

Why spent 10k to make your boat great if you can do it for 1.5K or less
 
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