Hello again all.
Four years ago I came on the forum for advice on changing a blown-up kohler courage sv470 for an SV 480 on our husquvarna lt 151. The swap went well and the mower has been working fine with regular oil, oil filter and fuel filter changes. Now, after about 200 hours, we've had our first little problem. Engine stopped in the middle of the half-cut lawn. The problem was narrowed down to a sticky anti-backfire solenoid. Changed it for the solenoid off the old SV 470 carb, and everything works like new again. But. Given that the old solenoid already had a few hundred hours on it changing it out for a new one ( or at least having a new one on hand ) seems prudent. The only thing is all the new ones we've seen are slightly different from the original in that they have a double wired plug ( shouldn't pose any problem ) and a rubber seal on the end of the solenoid needle, which the original solenoid needle does not have. So my question is, are the solenoids interchangeable, thread-wise and interior workings-wise? The carburetor is a walbro. I've included photos of carb, and both models of solenoid.
The second question is more out of curiosity. From what we've read it appears that a heat shield is recommended to protect the anti-backfire solenoid. How does the heat damage the solenoid? Does it cause mechanical distortion or electrical deterioration in the solenoid? Would heat of that intensity not cause the fuel in the carb bowl to vapor lock first? Slightly confused about this. Even more so given that the old blown-up SV470 engine has a heat shield and the SV480 does not...which may explain why the 470's solenoid has lasted at least twice as long as the 480's.....
Any and all information welcome! Thanks
Four years ago I came on the forum for advice on changing a blown-up kohler courage sv470 for an SV 480 on our husquvarna lt 151. The swap went well and the mower has been working fine with regular oil, oil filter and fuel filter changes. Now, after about 200 hours, we've had our first little problem. Engine stopped in the middle of the half-cut lawn. The problem was narrowed down to a sticky anti-backfire solenoid. Changed it for the solenoid off the old SV 470 carb, and everything works like new again. But. Given that the old solenoid already had a few hundred hours on it changing it out for a new one ( or at least having a new one on hand ) seems prudent. The only thing is all the new ones we've seen are slightly different from the original in that they have a double wired plug ( shouldn't pose any problem ) and a rubber seal on the end of the solenoid needle, which the original solenoid needle does not have. So my question is, are the solenoids interchangeable, thread-wise and interior workings-wise? The carburetor is a walbro. I've included photos of carb, and both models of solenoid.
The second question is more out of curiosity. From what we've read it appears that a heat shield is recommended to protect the anti-backfire solenoid. How does the heat damage the solenoid? Does it cause mechanical distortion or electrical deterioration in the solenoid? Would heat of that intensity not cause the fuel in the carb bowl to vapor lock first? Slightly confused about this. Even more so given that the old blown-up SV470 engine has a heat shield and the SV480 does not...which may explain why the 470's solenoid has lasted at least twice as long as the 480's.....
Any and all information welcome! Thanks
