Madden Cruise, lots of bow steer

[Still Afloat]

Well, the ice is finally off of the lakes and I took the little tinny out for the first time. It’s a Lowe 1448M, mod V Jon with a Merc F25ELH Jet. It‘s still a bare hull at this point and as expected it was tail heavy. Once the decks are on it, fuel, batteries and trolling motor up front it should help balance things out quite a bit.

I raised the motor 1” above the transom with a piece of 1 x 2” square aluminum tube which put the front top edge of the intake even with the bottom of the hull. The motor has manual trim and it was trimmed all the way forward. The hole shot had the bow shooting for the sky but it got on plane and ran about 22 mph at wot with no sign of cavitation. This was on a lake with a slight breeze and glassy to a lightly rippled water.

The boat was squirrelly has heck and it wanted to drive like snake swims. It was a real handful and I was being cautious because it felt like it could easily veer sharply and flip or just eject me from the boat. That could get real bad, real quick in the ice cold water. If the motor had power trim I would have trimmed up but, with it sitting heavy in the stern I didn’t want to attempt a hole shot with the motor manually trimmed any higher.

Any thoughts on the stability issue? Was this bow steer or was it just the center of gravity too far astern? Or both?

 

[FuzzyGrub]

I think you have the manual trim too far in, such tha the motor is driving the V hull down at the bow which is causing your "snake" like action. It is dangerous to operate like that. Adjust it so the cav plate is parrellel to the boat bottom, and try it again.

Moving weight forward, will help reduce the bow rise when getting on plane. If it is still a problem, you can try a foil, or my preferance, smart tabs.

V bow steer is normal at slow speeds, non planning speeds, with deep V hulls. I have never had it with my small boats, but my fiberglass bowrider did.

 

[Still Afloat]

Thanks Fuzzygrub. Yes, I thought the same about the trim and weight distribution. As mentioned, it’s still a bare hull and most the weight will go up front as the build progresses. The jet outboard height is probably close enough for now and I won’t mess with it again until the weight is balanced.

The main reason for taking it out at this stage was to see how she sits on the water with a 200 pound motor and to see how the motors runs. Motor seems to run quite well but, I think pods are needed to offset the weight of the motor.

 

[FuzzyGrub]

Sorry. I missed that this was a jet.

Trim it all the way in, and run a straight edge off the bottom keel and see where it contacts the foot. Then trim it to crankshaft verticle, and do the same check. If this hull was not for a jet, it will probably need to be raised more than an inch. A manual jack plate is often used.

Jets should not be trimmed out past verticle. That probably only gives you two other positions to try.

 

[Still Afloat]

Ok, I did the check at trimmed all the way in. It's even with the hull. I’ll check it at vertical.

Understood that Jack plates are commonly used and I can appreciate the positive aspects of using one. However, on the downside of things, moving the motor farther from the center of bouyancy will increase the balance issue. I think pods would be a must in this case.

It seems like a jack plate could be designed to lift the motor without moving it farther back.

 

[FuzzyGrub]

This is the manual one on OutBoardsJets: Manual Jack Plate

Try those other trim positions. Just out one, may correct for your high-speed control issue.

 

[Still Afloat]

Thanks. I didn’t see any prices on the OutboardsJets site but, I’ll do some more digging.

I set the jet to the vertical shaft position and checked again with a straight edge on the bottom of the hull. It’s a 1/4” above the hull. It’s on the second to the last hole. Maybe I should consider buying a tilt & trim upgrade.

I’ll throw some sandbags in the boat at the approximate weight and position of the fuel tank, batteries, MK Terrova, etc. and then take her for another spin.

 

[FuzzyGrub]

I found your prior post: THREAD

In there you mention that it is a "The boat is a Lowe 1448M, flat bottom with the mod V bow" vs a mod V bottom. Just so we know what you actually are running.

I'd try the one position back, with same loading as the maiden voyage and see if it corrects the high speed veering. ie change one variable at a time. Then try both again with weight distribution.

Most jets can run fully tucked in. As ours was stock, there was no gain in speed by trimming out. After I raised it one hole, can gain 2 mph trimmed out to verticle. The bow rises some, and can catch more wind. A jet will feel "loose" compared to a prop. IMO: dialing in height and transom angle (wedges) is probabably more benifitial than tilt/trim.

 

[JL8Jeff]

I had to add the transom wedges on my Lowe 1652 VT but I have a mod-v tunnel jet hull and it would porpoise without the wedges and being tucked all the way in. If I trim it out a little when I'm by myself, I will get a lot more spray. When I have people in the boat with the weight up front, I do need to trim it out a little to keep the bow up. It could be your flat bottom that makes it feel loose.

Here's a picture of my boat with the wedges and the motor trimmed in all the way. The front of the foot is just below the tunnel. If the front of your foot is just above the bottom of the boat, you might be 1 hole too high. I tried it 1 hole higher and got a lot of spray back so I went back down.

 

[Crazyboat]

I really know Jack S about how a JET will perform, but I'm thinking that it is tucked too far under thus giving you bow steer.

 

[Still Afloat]

Thanks for the input guys. Sorry for delayed reply, had to work on taxes.

Fuzzy, I’ll try it trimmed out and see what happens. I can’t really raise the motor any higher at this point without buying or fabricating a Jack plate.

JL, I wasn’t getting any porpoising or cavitation but, I find it interesting that you had the later.

I've been reading up on stability and center of bouyancy. I really think the 196 pound motor and my 180 pounds in back is just too much to ask from a small boat. I’m considering pods and maybe even remote steer. What’s the consequence of going with too large of pods, provided that there is still adequate clearance for the pump?

 

[FuzzyGrub]

Pods will help raise the transom and you can float over shallower water. They may help you get on plane, too. On plane, even if installed correctly, will have some drag and will takeaway from your top speed. It will not help your bow steer issue. If it does, its because of the speed reduction, which is not how you want to solve it. In fact, you should test that. Back off fom WOT and see if the bow steer is reduced or eliminated. If so, gives more credance to a trim or transom angle causing it.

Stick steer or maybe just a tiller extension should help your weight distribution and get on plane quicker. My concern is the high speed bow steer and understanding what is causing that.

How is the motor mounted? It sounded like you were using clamps vs bolt thru. Going to bolt thru, you can raise it higher. Not saying that is causing the issue, just another thing you could try.

 

[Still Afloat]

Thanks, Fuzzygrub. Wish I could post a photo me in the boat on the water. I think the issue with excessive weight near the transom would then be apparent. I’m doing this solo at this point and the lake is still pretty quiet so the chances a getting someone to snap a photo are slim.

The motor is clamped on, will bolt it on later when I have confidence that it’s close to the correct mounting height. Will post some photos this weekend.

The next lake test will be this weekend and I’ll report back.

 

[Skunked again]

https://www.ontheflyjackplates.com/


See if either of these help you.

 

[Still Afloat]

Thanks, SkunkedAgain.
I decided a couple of days ago that pods are a no-brainer for the little tinny. Just now returning from a biz trip and I need to do some measurement before making a purchase.

I’m leaning towards the Backwater pods. I spoke with Jake and he seems like a straight shooter.

At least right now, I think the cons of a jack plate outweigh the pros for this boat. I think the height is probably pretty close and my money would be better spent on a OEM power trim upgrade. The next lake test may change my mind though.

 

[Skunked again]

You are more than welcome!

 

[Still Afloat]

Well, not much of an update. I got the big tinny out of storage on Saturday so the little tinny can wait until the pods arrive. Ended up ordering the Beavertail pods because they matched the transom angle. The Backwater pods are built for a 18 degree transom angle and the Beavertail are built for a 15 degree transom angle. The 2023 Lowe 1448M transom angle is15 degrees.

So according to my limited mathematics skills and poor memory of the calculations that I made a week ago, using the Backwater pods would have placed the rear of the pods about 2.25 inches above the bow line. That would cut the pod buoyancy in about half based on a 3 inch draft.

 

[FuzzyGrub]

What was your “before” draft at the transom?

 

[Still Afloat]

Hi Fuzzy, I measured it the other day but, I don’t remember for sure Think it was five inches or so at the transom before I got in. The front half of the boat was out of the water. So you can see why I was reluctant to take her out again without some weight on the bow.

I did some really rough CG/CoB calculations with the all the gear but, without the pods and was still about 70 pounds heavy at the transom before I climb aboard to man the tiller. I think the pods will be huge help but, my moving my butt closer to the bow may still be required.

I agree with your statement of changing one thing at a time but, that‘s not always practical. The balance and stability was so far off that I‘m not comfortable taking it out again without more floatation in back or more weight up front.

Edit - I suppose I can throw some weight in the bow and give it another try with the trim fully forward. Then try other trim settings.