plywood sandwich, decking/floor

[aquaprouts]

Hello....recently purchased a good condition 77' 196 with a 93 merc 150 efi.....stearn decking behind bench seat a bit sagging as well as the fuel tank coffin cover....can someone tell me the correct thickness of plywood to reglass in? Additionally can anyone tell me the original thickness of the teak shim trim that the center console sits on?  Also, my merc has a 5 bladed high five prop...engine came off a freshwater bass tourney boat......any pros or cons with this on my 196?....tops out around 41 mph but need to hitch a tach up.....thnx for your help on my project

[dburr]

Welcome prouts!

Any idea if the deck has been done before? If it is soft the are about 472 1/2 different ways to fix it, how you do it depends on your skill/desire. The more you can tell us directly about your issue the more concise the answers will be. Pictures are a big help too..

Do you want to replace the teak or do you want to go big like RickK did and put toe savers under the console?

What's the numbers in the wheel? Five blade is cool, pitch and diameter will give the 196 guys an idea of how close you are to good running numbers, it will also depend on how you want to use the boat..

Standing by..    

[aquaprouts]

Thnx for the welcoming.....the floor deck behind the bench seat has had no work done other than being jacked up below.....the upper and lower skins are sound and some disintegration of the wood coring directly in front of the bilge access door.....an approx 30 x 24 inch area.....was planning on cutting the upper deck skin dead center from the bilge access door to the coffins stearn panel end point......peel it back, remove rotten wood and replace and glass in new plywood subfloor and lay top skin/glass back on....sound good?  Im not familiar with toe savers...any pics?....was planning on replacing the console teak shim lift trim as original or perhaps with a trex or other man made lumber if i can find one resembling a teak finish and that it can be routed for a bullnose profile.....any suggestions here welcome......any opinions about using a doel/foil type fin on a 196 with a 150 merc efi.....advantages or disadvantages.....thnx! Capt kurt

[seabob4]

Kurt, by mentioning a Doelfin, I assume you are having holeshot issues...which very well could be related to the hi-5.  Yes, you need to put a tach on her to see your WOT, preferably around 5500...

[aquaprouts]

No real issues with hole shot....hve been on the boat for only several hours....i happen to have a se 300 fin from the boat i am selling so just curious if others have found a benefit to using a foil fin on a 196 with similar power(150 hp).....i did find that there seems to be a short trim range
on the 196 with a 20 inch shaft/transom.....you can only trim the engine so much before cavitation.....was not sure if the shorter blades on my 5 blade high five prop may contribute to this as there is not as much length of prop biting the water.....thnx

[GoneFission]

Hello....recently purchased a good condition 77' 196 with a 93 merc 150 efi.....stearn decking behind bench seat a bit sagging as well as the fuel tank coffin cover....can someone tell me the correct thickness of plywood to reglass in? Additionally can anyone tell me the original thickness of the teak shim trim that the center console sits on?  Also, my merc has a 5 bladed high five prop...engine came off a freshwater bass tourney boat......any pros or cons with this on my 196?....tops out around 41 mph but need to hitch a tach up.....thnx for your help on my project

OK - here are some responses to your questions:
-  Original plywood thickness for the deck core was 1/2" - the teak piece that the console sits on was 3/4" thickness, but some models left it out and screwed the console directly onto the deck...  
-  Nothing wrong with a HighFive - I'm running one and it's the best prop I've ever run.  However, I would guess the correct pitch for your setup would be a 19" pitch - check the prop and see what you are running.  A '93 Merc 150 should turn about 5500 RPM at wide open throttle with the right prop - I'd guesstimate that would be mid-40s with your setup.
-  Don't run a Doel-Fin or other fin on your mota - on the Aquasport, it will jus slow her down and make her suk mo' gas.  But do make sure the mota is at the right height on the transom - that can make a big difference!

[dburr]

John votes no on the fin, I will vote yes.  Every boat I have ever had I have put one on, I really like the trim response with them and don't care about the difference of the loss of 1-2kts at top end.  I am not however running a 5 bladed wheel and that could make a difference on the response.  I am much happier with the trim control that the fin gives with a 3 bladed wheel and it cuts down on porpoising on the Sport 15 whaler with a 70 that I have.  On that little wood chip the fin also helps keep some part of the boat in the water when running close to full chisel   , damn thing is boarder line scary. Kinda like I imagine the 196 will be with a big motor :twisted:... That said, motor height is REALLY important, to low and fuel consumption goes up and speed does drop more then 1-2..

I have one on the 222 Osprey and get much better trim response then without. Course it is a heavier boat too.

Take look at RickK's 170 rebuild and you will see what I am referring to about a toe saver console, ought to be a new man law that we all have them..

[dburr]

Once you cut into the deck it doesn't make any difference how big the hole is, the fix will be the same, just more cost in materials with a bigger hole. I am not a 196 guy so I can not go with particulars.. If the soft spot does not come close to the stringers you will should/need to put butt blocks under your patch so why not cut back to the stringers to have something for the patch to land on? Again, lots of options...

[gman 82 aquasport]

Agree with dburr here on cut it back so the edges are over the stringers for better support. My 82 19-6 had 1/2 inch between the glass layers Hope that helps..

As for the fin, I have run my 19-6 with and without it, I run a Johnson 150 with a 25 inch shaft..but I need to raise my motor another bolt hole..I like mine with the fin on it...turns better and tracks better but that's just my .02...play with in with the fin on and off and see which you like better..
I can get about 36knts out of mine at about 5300 rpm..15x17 stainless 3 blade prop..nothing special

[slvrlng]

I was going to do the same repair as you until I decided to inject the soft spot in my floor.  I drilled 72 1/8 holes and injected with thickened epoxy. I was worried about cutting out the section of upper glass and then getting it back in level. My repair worked really well and the spot is not noticeable at all anymore. I have a thread on doing the repair, I will try to find a link.

[slvrlng]

Here ya go !!!


viewtopic.php?f=8&t=10525

[aquaprouts]

Thanks for the epoxy info gents.....in my case, on my 196, i have a decking void/hollow spot of up to 1/2 inch in a 2x3 foot area behind my bench seat between the stearn off coffin cover and the bilge access hatch....will the resin trick work filling such thick voids?...it seems it would be more work as described than simply cutting the top later/skin with a utility knife or saw(just enuff for access), peel it back and rip out and replace the core plywood.....this would leave the nonskid more intact as i think i can cut a long a center seam on floor that has no nonskid and also cut a seam horizontally on the bildge access hatch at its forward side at the bottom of the top layer of glass.....i can also cut a non visible working horizontal cut similarly below the surface at the stearn side of the coffin hatch seam.....great info from the members here!

[GoneFission]

Here's a thread on fins:
viewtopic.php?f=13&t=5684&p=38561&hilit=doel#p38561  

Good luck!

[fitz73222]

Well I guess I'll throw in my $.02 on the Doel Fin... I've used them on various hull and engine combos in the past and found that they can make a big difference on a boat that needs one and have a negative effect on one that doesn't. A boat that porpoises or is stern heavy; it will create enough additional lift to actually increase speed in the midrange and top end because it changes the hull attitude to a more desireable angle or in the case of porpoise; will force the stern up and bow down and eliminate the obnoxious hull hop, allowing you to run faster at the same throttle setting. On a hull that has no basic issues it will slow you down because of the addtional drag and stern lift. I have seen them actually counter positive trim response because when you trim the engine out your actually pushing the stern down which in turn lifts the bow. By design, the Doel Fin creates more stern lift which is an opposing force to pushing the stern down created by positive trimming (out) For a 19-6 with a 150 you should not need one. As you mentioned, start with tach and see what your WOT numbers are; I suspect you have too much bite with a 5 blade, giving you a sluggish holeshot and your top speed number is low; I think you should be seeing easy mid-forties. I would be looking at a 3 blade for this application. My favorite is a Stilleto or a Mercury Laser but even going to stock cupped aluminum prop should wake this boat up.