2019 Grizzly Tohatsu 20 short shaft
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2019 Grizzly Tohatsu 20 short shaft
First I want to thank all here who responded to my help requests. Saved me a lot with my learning curve.
Hung the engine yesterday using a 1 ton Walmart chain hoist. 40.00. Works great. Started immediately. Very quiet, will be more quite in the water with prop exhaust.
The cav plate sits 1 1/2" above the bottom of the transom. Talked to a guy who has the same boat and engine and he says no cavitation. Says he gets 25mph WOT. I'm taking it out tomorrow so we will see. I have a tiny tach but haven't decided where to mount yet. Both batteries are mounted in front hatch. BTW got the engine from Online Outboards. Great to deal with. Gave a Military discount.
I'll post after the test run. Cheers
Hung the engine yesterday using a 1 ton Walmart chain hoist. 40.00. Works great. Started immediately. Very quiet, will be more quite in the water with prop exhaust.
The cav plate sits 1 1/2" above the bottom of the transom. Talked to a guy who has the same boat and engine and he says no cavitation. Says he gets 25mph WOT. I'm taking it out tomorrow so we will see. I have a tiny tach but haven't decided where to mount yet. Both batteries are mounted in front hatch. BTW got the engine from Online Outboards. Great to deal with. Gave a Military discount.
I'll post after the test run. Cheers
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2019 grizzly 1448
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2019 Grizzly Tohatsu 20 short shaft
Nice rig!
2016 Alumacraft 1648 NCS - 2020 Yamaha 25 HP Tiller - 1992 Johnson 9.9 HP Tiller
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2019 Grizzly Tohatsu 20 short shaft
Congrats. That should be a great fishing rig. Those 20 tohatsu motors are over achievers. Should perform great.
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2019 Grizzly Tohatsu 20 short shaft
Yes nice rig for sure.
Only thing I suggest, is your transducer is angled to low. Once you pull the boat out of the water. And see the scam line, ( how the boat is leveled in the water) you can rise the end upward. So it’s level in the water. This makes a huge difference in performance.![Image]()
This is a pic of mine. Looks odd, but I have a lot of rear weight. There are UTUBE videos on how to use levels to gain the correct set position. But hey the scam line doesn’t lie![Image]()
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Only thing I suggest, is your transducer is angled to low. Once you pull the boat out of the water. And see the scam line, ( how the boat is leveled in the water) you can rise the end upward. So it’s level in the water. This makes a huge difference in performance.
This is a pic of mine. Looks odd, but I have a lot of rear weight. There are UTUBE videos on how to use levels to gain the correct set position. But hey the scam line doesn’t lie
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2019 Grizzly Tohatsu 20 short shaft
Ok, I didn't wait. Took it out today. I hooked up the tin tach. Wound 3-4 times around the plug but it showed 3000 rpm at WOT. GPS showed 25mph. I think I didn't put it on right. The motor does cavitate slightly. I get alittle spray back at the transom. Looks like its coming from the anti cave plate. I can adjust the "tilt" up while running but not down. Didn't seem to make much diff with the spay. I read somewhere for a fix for this but I forgot what they did. Recommendations?fyr4efect wrote:First I want to thank all here who responded to my help requests. Saved me a lot with my learning curve.
Hung the engine yesterday using a 1 ton Walmart chain hoist. 40.00. Works great. Started immediately. Very quiet, will be more quite in the water with prop exhaust.
The cav plate sits 1 1/2" above the bottom of the transom. Talked to a guy who has the same boat and engine and he says no cavitation. Says he gets 25mph WOT. I'm taking it out tomorrow so we will see. I have a tiny tach but haven't decided where to mount yet. Both batteries are mounted in front hatch. BTW got the engine from Online Outboards. Great to deal with. Gave a Military discount.
I'll post after the test run. Cheers
Gets up on plane very easy. Transducer was working fine and didn't loose display at 25mph. I will adjust it like Gatorglenn mentioned to see if any diff.
All and all I am satisfied with my decision to go with the 20hp on this boat. The engine came with a 9.25 x 11.5 prop. Any advise welcome.
2019 grizzly 1448
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2019 Grizzly Tohatsu 20 short shaft
If you can get a good rpm reading. And it’s still 3000 I would go to a 10p. It’s a heavy boat for its size.
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2019 Grizzly Tohatsu 20 short shaft
Nice. I like how my grizzly rides on the water. I still need to mount a driver's seat off-center like yours.fyr4efect wrote:Ok, I didn't wait. Took it out today. I hooked up the tin tach. Wound 3-4 times around the plug but it showed 3000 rpm at WOT. GPS showed 25mph. I think I didn't put it on right. The motor does cavitate slightly. I get alittle spray back at the transom. Looks like its coming from the anti cave plate. I can adjust the "tilt" up while running but not down. Didn't seem to make much diff with the spay. I read somewhere for a fix for this but I forgot what they did. Recommendations?fyr4efect wrote:First I want to thank all here who responded to my help requests. Saved me a lot with my learning curve.
Hung the engine yesterday using a 1 ton Walmart chain hoist. 40.00. Works great. Started immediately. Very quiet, will be more quite in the water with prop exhaust.
The cav plate sits 1 1/2" above the bottom of the transom. Talked to a guy who has the same boat and engine and he says no cavitation. Says he gets 25mph WOT. I'm taking it out tomorrow so we will see. I have a tiny tach but haven't decided where to mount yet. Both batteries are mounted in front hatch. BTW got the engine from Online Outboards. Great to deal with. Gave a Military discount.
I'll post after the test run. Cheers
Gets up on plane very easy. Transducer was working fine and didn't loose display at 25mph. I will adjust it like Gatorglenn mentioned to see if any diff.
All and all I am satisfied with my decision to go with the 20hp on this boat. The engine came with a 9.25 x 11.5 prop. Any advise welcome.
Just curious, what did the tach read at idle? I'm wondering if its setup right.
That 20 should troll nicely. Enjoy the new rig.

2018 Tracker Grizzly 1648
2018 30 HP Suzuki DF30A
2018 30 HP Suzuki DF30A
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2019 Grizzly Tohatsu 20 short shaft
I wound 3x around 1 spark plug right up to the cap. Then I attached the white wire to a engine ground. At idle I think it was 600. I'm going mess with it today. Maybe 2x around. Im more annoyed with the spray. I cant lower the engine. I still have my mini-jacker that didn't fit the Merc 25 LS, but it will fit this 20 as the mounting holes are 8" apart and the jacker plate is 11" I thought if I keep it the same height but 4" offset it might solve my cav problem. I'm not sure a hydrofoil is an answer. I am very new to this but I am not opposed to experiment. The 14 grizz moves out pretty good with the 20 and handles well. Thx for your input.jasper60103 wrote:Nice. I like how my grizzly rides on the water. I still need to mount a driver's seat off-center like yours.fyr4efect wrote:Ok, I didn't wait. Took it out today. I hooked up the tin tach. Wound 3-4 times around the plug but it showed 3000 rpm at WOT. GPS showed 25mph. I think I didn't put it on right. The motor does cavitate slightly. I get alittle spray back at the transom. Looks like its coming from the anti cave plate. I can adjust the "tilt" up while running but not down. Didn't seem to make much diff with the spay. I read somewhere for a fix for this but I forgot what they did. Recommendations?fyr4efect wrote:First I want to thank all here who responded to my help requests. Saved me a lot with my learning curve.
Hung the engine yesterday using a 1 ton Walmart chain hoist. 40.00. Works great. Started immediately. Very quiet, will be more quite in the water with prop exhaust.
The cav plate sits 1 1/2" above the bottom of the transom. Talked to a guy who has the same boat and engine and he says no cavitation. Says he gets 25mph WOT. I'm taking it out tomorrow so we will see. I have a tiny tach but haven't decided where to mount yet. Both batteries are mounted in front hatch. BTW got the engine from Online Outboards. Great to deal with. Gave a Military discount.
I'll post after the test run. Cheers
Gets up on plane very easy. Transducer was working fine and didn't loose display at 25mph. I will adjust it like Gatorglenn mentioned to see if any diff.
All and all I am satisfied with my decision to go with the 20hp on this boat. The engine came with a 9.25 x 11.5 prop. Any advise welcome.
Just curious, what did the tach read at idle? I'm wondering if its setup right.
That 20 should troll nicely. Enjoy the new rig.
2019 grizzly 1448
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2019 Grizzly Tohatsu 20 short shaft
The tach might be set on 2 stroke
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2019 Grizzly Tohatsu 20 short shaft
The idle RPM sounds fine, so I would assume the tach is setup correctly.fyr4efect wrote:I wound 3x around 1 spark plug right up to the cap. Then I attached the white wire to a engine ground. At idle I think it was 600. I'm going mess with it today. Maybe 2x around. Im more annoyed with the spray. I cant lower the engine. I still have my mini-jacker that didn't fit the Merc 25 LS, but it will fit this 20 as the mounting holes are 8" apart and the jacker plate is 11" I thought if I keep it the same height but 4" offset it might solve my cav problem. I'm not sure a hydrofoil is an answer. I am very new to this but I am not opposed to experiment. The 14 grizz moves out pretty good with the 20 and handles well. Thx for your input.jasper60103 wrote:Nice. I like how my grizzly rides on the water. I still need to mount a driver's seat off-center like yours.fyr4efect wrote:[quote="fyr4efect".... Any advise welcome.
Just curious, what did the tach read at idle? I'm wondering if its setup right.
That 20 should troll nicely. Enjoy the new rig.
I don't know the WOT range off hand, but 3000 RPM sounds too low to me, but 25 MPH sounds great.
I guess its just over propped like someone else mentioned?

I'm sure you'll get it figured out. I'm still getting familiar my setup and I've
been on the water 4 or 5 times.

-jasper
2018 Tracker Grizzly 1648
2018 30 HP Suzuki DF30A
2018 30 HP Suzuki DF30A
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2019 Grizzly Tohatsu 20 short shaft
You could be correct. The Tinytach 2AM I have is for outboards [ except Honda ] I spoke to TinyTach and he didn't ask 2 or 4 stroke. The instructions doesn't ask if your engine is 2 or 4. It just says wire around a plug wire. He said try wiring to both cylinder plug wires as it might be picking one input instead of two.So we will see. That 3000rpms Im getting is half what WOT should be for this 20 hp. 5400-6100.GYPSY400 wrote:The tach might be set on 2 stroke
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Ok after hooking on both wires the idle is 1000 rpm, on one it was 500-575. So looks solved. Ill water test it Mon.
Thx for your input.
2019 grizzly 1448
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2019 Grizzly Tohatsu 20 short shaft
Tiny techs have been around for ever. Used on mostly 4 stoked motors. Lawnmower, generators. All sort of things. But the biggest thing I found over the years is, putting one wire only on the number 1 cylinder, as directions say. Your idle rpms should be between 750-900 when the motor is fully warmed up.
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2019 Grizzly Tohatsu 20 short shaft
[quote="gatorglenn"]Tiny techs have been around for ever. Used on mostly 4 stoked motors. Lawnmower, generators. All sort of things. But the biggest thing I found over the years is, putting one wire only on the number 1 cylinder, as directions say. Your idle rpms should be between 750-900 when the motor is fully warmed up.
My directions don't mention #1 cylinder, neither did the factory guy. Thx for your input.
My directions don't mention #1 cylinder, neither did the factory guy. Thx for your input.
2019 grizzly 1448
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2019 Grizzly Tohatsu 20 short shaft
Well ok, they must have changed. All 3 I’ve bought (some time ago) all said to. Go luck and it’s a really good looking rig
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