cant get boat to troll below 1.5 1.6
I have 36 buggy bags on each side. plus two more socks. In all i was dragging four bags. I caught three hogs today d can area. but want to able to troll harnesses eventually . Maybe i'll trade up to 48's . 20 foot four winns with a 220 volvo penta. 1.5 is as slow as she rolls.
what rpm does your motor idle at
you kinda hit on what i was thinking i am not a troller and dont know much about recomendations of bag and stuff. but do you know what prop you have...a larger diameter small pitch prop might help, but that could also change the way your boat runs on top end and comes on plane. guess you are running something close to a 13.75" diameter 21" pitch 3 blade now your gear ratio of your outdrive will effect it too. but you could look at something like 14 to 14.5" 19 pitch 4 blade. With the 4th blade and larger diameter it will add a little more prop to water contact area thus making more drag, but will provide a little extra grip on the water so it will be harder to blow the prop out of the water if you go a little to small in pitch...the smaller pitch should net you about .25-.5 mph slower at idle. If you try this just make sure your prop clears everything on the outdrive and the anodes, they make differant shapes of lengths of them to fit the needs.
Another thing to check is to make sure your motor is actualy running at the rpm your tach is saying boats have a known issue of the tachs being off towards the high side. I think this is to provide a cushion in the top rpm range so ppl dont over rev the motor. the tach in my 241 four winn liberator is about 200 off at idle and about 550 off at full throttle. so maybe put a good tach on just to check to make sure your running at too high of rpm if your running at 850-900 or something you could try to turn the idle screw down a touch to something like 650 or 700 as long as the motor does not load up on you and stall you can experiment with this. Some v-8 can run as low as 500 and still be smooth and not load up. I would not try to go that low but check your specs on the motor, you could try to go 50 or maybe even 100 less than just to try and see what happens.
the only bad thing about turning the idle down is be careful to watch the temp gauge sometimes the lows rpms can cause waterflow to go down due to the slower spinning speed of the impellar and circulating pumps which could cause the temp to go up if not enough water flow is going through the motor.
hope maybe this helps i would try the idle screw first if it was me...does not cost anything
also not sure if your boat has trim tabs.....but if it does you could try to put them all the way down to cause some more drag if you have not. I know on my boat if i have them up as running on plane when idling through the river my boat tends to walk back and forth and take alot of steering input like it has play in the steering.....which it does not...i put the tabs down and it help settle it out and tracks better. If you dont have them adding might help but not cheap.....if you do have them..you could also try adding a stainless steel plate to make them a little bigger to cause more drag.....this can cause them to be over sensitive though if too big.