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my bj29 v3 runs kinda hot . stock setup here with a cnc x440/3 blade prop .timing 7.5
first run was with 5500 mah lipos mid tray , top speed 49.1 . motor temp 170 esc 130ish.
second run 5000 mah all the way back in trays (lighter lipos too) motor temp 150 esc 100-110ish .top speed 51.4
strut is level with sponsons with boat sitting on table .
should i raise the strut? can you tell by my running video if its running too wet?
https://www.youtube.com/watch?v=frhz26dfbwQ
Raise strut to 1/8" above the table ( I run mine at a slight negative angle ). One prop blade should be in the water when at speed.
4S or 6S?
running 6s
Gotta be 6S with that prop and stock motor to get those speeds. What ESC? The motor is likely now damaged with those temps if done often...
.
I was going to say motor life going south quick too at that temp.
......
everything stock cept the prop . i dont run it like this all the time ,at this temp . i should be able to get the temp down . second run was only a 2 minute run ,i was being more cautious because of the first run temps
I never did like the stock setup. Was it fast, yes. Did everything run hot (even the ec5 connectors), YES. Changed out all the guts pretty quick to Seaking180/leopard 4074. Ran faster, smoother and alot cooler (even the ec5 connectors). Try a 2 blade prop in the 43mm range with the strut raised and the packs to the back. Motor still smoking, I would have no trust in it. Like Fluid said the motor could be scorched.
i raised the strut 2mm hope to get a run in thursday if the weather is better . yes i have read things run hot with this boat .but its still new ,i have no desire to change anything yet .i will update my findings
raised my strut about 2mm ,went for a run . lost about 2 mph and temps werent any better ,after 4-5 passes and maybe 2 minutes max motor was again 170 coming in . esc wasnt too bad 130 max.
anyway ,i am going to put the strut back where i started and start looking for other ways to get the temps down .
what if i go the other way with the strut?
check my pics ,the first line is where i started and you can see its raised up about 2mm. i scribed the strut with a razor knife so i can see where i started and where i been .
anyone ever use a transom pickup for water cooling on these boats? for now i will start drilling the water openings open in the rudder, the top of rudder nipple ,ect,ect....
Attachment 151130Attachment 151131Attachment 151132
I've said it a number of times before, your cooling lines are plumbed wrong.
line goes to motor first ,thats where i need the most cooling . if i were to turn the cooler to get water to enter at bottom the top nipple would be straight up and not allow me to close the hatch .Quote:
Originally Posted by fweasel
what are you suggesting?
what were your temps when you ran the x440/3?
Do you always run the drive dog that close to the strut? You need at least 4mm gap there. That can heat things up.
no i usually dont ,looks like i did today eh?Quote:
Originally Posted by ray schrauwen
i will open up the gap .someone else noticed my rudder was not 90 degrees and i have corrected that now as well . are these washers between the drive dog and strut even needed ? i could take those out and have a nice gap there . it came with them out the box .
i worry if i open the gap too much there wont be enough flex shaft in the collet .removing the washers would take care of that .
i also put my strut back where it was during my best run . Rafael noticed something with my prop too which i have corrected now .
update ....
i straightened out the rudder ,it was pitched inward a little before .
i removed the plastic washers at the drive dog'
i drilled out the rudder water inlets and the nipple on top the rudder
left bigger gap between strut and drive dog .
i smoothed out the leading edges of the prop ,Rafael noticed it was kind of blunt .(good eye ,thanks)
last run i did was near 50 mph and temps were down to 135 motor and 110 esc .
i have since then also drilled out the water outlet to a larger size . will be taking a test run today .
Thanks for update. I just got MG I was wondering if I need to do anything before I ran it.
How far did you space the drive dog?
What I plan on doing before I take out on the water.
-I have OSE strut, plan installing that and setting the strut height 1/8"
-Drilling the outlet,inlet,nipple out bigger
-Make sure the cooling lines are correct
-Making sure the rudder is straight
-Take the spacers out at the drive dog and spacing it 4mm
-Get the prop sharpened and balanced
-Check the programming of the esc
sounds like all the right stuff to do .4mm is plenty . i set my timing at 7.5 . should have new temp readings little later .hopefully even lower .
interesting run today . motor temp still 150 when i brought it in . esc was less . motor temp concerns me but i do keep reading that these run hot .
anyway check the video . had a blowover today .
https://www.youtube.com/watch?v=cvbtZlUx1iY&feature=youtu.be
New owner of my blackjack ran 59mph last weekend, motor and ESC were both under 110. He's switched to a wire drive and dual cooling rudder since I ran it last.
You know what dual cooling rudder he used?Quote:
Originally Posted by fweasel
yeah i might try a dual cooling rudder as well . or break down and buy another motor .Quote:
Originally Posted by fweasel
This oneQuote:
Originally Posted by eric113
https://www.offshoreelectrics.com/pr...prod=ose-83275
Had to shorten it , open the hinge pin hole a bit then sandblast and paint black. Added an additional water outlet to the other side of the hull
Here's the link to my post on it
https://forums.offshoreelectrics.com...pickup-upgrade
Did about a 4min run temps were under 110
On both motor and esc. Took it back out to finish the packs off hit the lvc. Brought it back in motor was in the 130's and esc was mid 100 and teens. Lakes around here are still pretty cool so I'm not sure if the dual rudder is helping or not