damo83

Hay guys, I have finally completed my 42" "Wild thing" powered by a 26cc Chinese marine engine, I have upgraded the carb to a walbro 644. The pics were taken just before completion. I took it out for a spin today and was happy with the first run. I am running a prather 280s prop and am getting about 65km/hr. I have a few questions for all you experienced boaters. Firstly when I get on a plane the boat seems to lean to one side the side that I last turned on. I have not yet installed trim tabs and was wondering If installing them will fox this problem. Secondly I have read a number of threads and sites on carb tuning and am having dificalty getting a steady mid range or high end. Bu this I mean, if I tune the H needle to get good mid range it boggs down when above half throttle, and when i tune for high speed I have no mid range. I have to quickly go to full throttle from idle or the boat stalls. Could this be that the prather 280 is too bug fot the motor. I am currently waiting for a 270 which I have purchased.

I look forward to all comments any help is greatly appreciated.

Regard Damo.

dwr9

Trim tabs will probably help, but if you have to adjust them down too far to stop the boat from leaning it will slow the boat down. Make sure your prop is sharp also. The 280 may be too much for that engine, see how the 270 works when it comes. I haven't heard too many good reports on those cheap Chinese engines. I use a 644 and I have the low needle set at 1 1/4 turns out and the high set at 1 3/4 out. However thats on a Zenoah with a tuned pipe so yours may need totally different settings. Have you tried richening up the low needle some after adjusting the high for good top end? What kind of tubing is that you're using for your engine cooling? If it's plastic tube it may melt. I would switch to silicone tube if it were me. The boat looks really nice. Doug

martno1fan

I think the leaning is due to the motor been too top heavy for the boat,when you turn shes struggling to right herself due to the high centre of balance.Def change that fuel line your using for cooling and try and trim it shorter,those motors dont rev very well by all accounts.Even an air cooled weedy would probably run better but def give it a go,id think a 270 is too small for it,the 280 is a better prop for it but only if its sharp,maybe a 275 would be an option.By the way its not a wildthing it looks like Dougs 48" vee to me just scaled down a bit?.Nice looking boat well done on the build,would be better suited with a smaller motor like a zenoah or even a nitro .
Mart

MrMikeG

Show your radio box and rudder linkage. Sounds like too weak of servo or too small of push-rod. Mid range is tuned with the low needle more than the high, if it is stalling richen up the low end.

damo83

Thank you for your tips, they are greatly appreciated. This is my first boat and the reason for the cheap engine was that I didn't want to spent too much cash and then find that RC boating was just a phase that would pass, However it is quite the opposite and am absolutely loving it and am going to invest in a Zenoah would you guys recommend a 23cc or the 26cc. amd yes it is one of Doug's boats I got the plans from Model power boat and they called it the wild thing so I do the same... Ill defiantly try the trim tabs and see if it fixes the problem with the lean. Ill keep you guys updated on the progress. If anyone is interested here is a video link of the first run Ive since put the prather 280 and am getting a fair bit more speed. The prop I used in the video is just a cheap ebay thing.

http://www.youtube.com/watch?v=xfNrGMMn6mI

Thanx again for the help...
Damo.

isola_d_elba2007

Are you sure you are getting 65kmh? Did you use a GPS.

dwr9

If you are going to keep the motor stock I think the 231 is the better motor. If you are going to get a modified motor go for a 260. DOug

MrMikeG

If you get the race bug then a 231 runs in 25 and under class and a 260 has to run in Open class.
There is a big race at Carribean Gardens coming up the weekend of July 24th.

damo83

Ye I have been looking at the 23cc, I don't know if I am going to race but it's defiantly a thought. Doug, why would the size motor depend on whether it is going to be modified or not?? I might go to the race day and have a chat to some of the guys. The thing I found really great about the Zenoah's is that the rebuild kits are readily available unlike other motors "Chinese" in particular once they are stuffed there only good for the bin.

Thanx again for all your help

MrMikeG

Look me up if you go, will be there late friday to tune and sat, sunday to race. Look for the "PM Boats" trailer [8D]

damo83

Will do Mike. I am eager to meet guys from Victoria, I am from Geelong and am interested in joining the Western district club in Altona, however I went down there on one of their scheduled days and there was no one in sight I stayed there for about an hour then left. I have been truing to contact them via email but all my messages come back saying message unable to be delivered. Do you know anyone from the club??? I gather that you are a member of the Carribean Gardens club. I wouldn't mind joining that either just the travel may be a bit much from Geelong... I'll C you there.

MrMikeG

I'm a member of Adelaide's club as it is closer to me. I have raced at Altona though, not sure what is going on with the club right now. The Carribean gardens boys will be able to let you know better as many travel between both clubs. Cherry lake is a great place to run. I think there is another Melbourne club just starting up as well.

dwr9

In stock form the 231 revs higher than the 260 due to a lighter piston and deeper transfer ports. The 260 seems to have an advantage in modified form. Doug