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GO 435 running hot

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Preston

Active member
Need some help from you GO435 fellers out there. Got a runout engine we put in our 13'6 Cottonmouth. Swinging a 72" Whirlwind SP , using a large JJ oil cooler (mounted below the engine ) . Problem is she wants to run hot after about 10 minutes of light running, 2200-2800rpm. Anyone got any suggestions on cooling this engine down. We're running an MA4-5 carb , and have the prop pitched to give us 3450rpm on the trailer.

PW
 
Don't know much about the Whirlwinds but I would say that is considerably under pitched. Considering they will usually turn a tad harder on the water. Somebody correct me if I am wrong but I would say 2900-2950 on the trailer would be the most???

Don't know anything about mechanically making it cooler but you could always look into a shroud. I put one on my anglevalve 540 and makes a world of difference.
 
Thats a gear reduction motor thats why the RPMs are high. When you say running hot, do you mean oil temp or cylinder head temp? If the oil temp is climbing check the top oil screen between the mags, if it is pluged it will cause the system to buy pass the cooler all together.



Kevin
 
cfth - I would agree with your post.

Turning even a geared engine at 3450 RPM on the trailer seems a tab bit high. Typically it seems that you will turn up a few more RPMs at max throttle on the water than on the trailer. A lot of boats I know are pitched at least 50 RPMs less than maximum on the trailer.

Sounds like it might be leaned out like Waterthunder said. Easy to do that by accident on that carb. I know one that smoked a couple cylinders because it was leaned out by accident.

Good Luck
 
Checked the plugs today... not lean . As a matter most all of them looked to be burning normal , and a couple maybe looked a little rich. The carb is a JJ rebuild MA4-5 that was tested on a 260hp O540 ...ran very well there. What Im wonderin is if the oil cooler bypass valve should be removed and plugged to produce full flow through the cooler. I'm not that familiar with that procedure on this engine so anyone can shed a little light , sure might help.
 
Preston,

cchardt on this board is trying to run an aircraft gearbox on a carmotor and wondering what oil to use in it.

Jim
 
Preston don't know if this will help but i'm having a similar problem with a 520 cont. converted to carb and the carb came of a straight valve 540 my motor also runs warm but not lean. a very well respected race motor builder in my area said my motor is under carbed causing it to work harder to breath and a larger carb will likely help out
 
I'm gonna watch this one, who knows I might need this info one day. Let us know if and when you get it figured out. Good luck with it. Later Cajun
 
Well heres what I've found so far...after talking with D.G. I discovered this engine has no oil viscosity bypass valve, its been removed. So he sends me one , install it , now its running cooler from 175-190 when we ran it this afternoon. Mostly ran in deep water and a little hill. However I gained about 10 lbs of pressure at idle hot...from 30lbs to 40lbs. Im going to check head temp this weekend so I will then know more about that later. J.J. tells me he does away with the vernatherm valve completly on the 0540s and that some type of valve or passage block(between the outlet and return cooler line) has to be there in order to route pressure oil through the cooler. I had none before insalling the viscosity valve , and was experiancing stagnant oil in the cooler. The following artical talks a little about this http://www.sacskyranch.com/eng18.htm Now with this in mind has anyone run or running a 435/480 that has elimaninated the veratherm or oil viscosity bypass valve and installed a block between the oil cooler outlet and return? This would assure constant flow instead of controlled flow for these engines and should help to reduce oil temp . Im sure this has been discussed in the past...can someone put me on it.
 
I discussed that with Jr Jurnigan on the phone for a 540. He uses a restrictor, give him a call.

Jim
 
Jim, I'm not positive, but I think that's who he was talking about when he said "J.J."

Not sure who D.G. is though....
 
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