The original transistor was a 2SB1780, in a weird package slightly larger than TO-92. You are right, assuming that the solenoid and everything else is working right, but if that were true the transistor would never have died.
Assuming a worst case Vce of 300mV at 500mA, that's 150mW. Easily done, unless there is a fault somewhere.
I think I will test the wiring by shorting the transistor pads through a 4R resistor and DMM, and see if the current is what is expected. For all I know the last owners might have sold the car after the purge valve fried the transistor and replacing it didn't fix the engine light.
The transistor itself is far more damaged than the traces leading to it. I would think if it were a direct short, the traces would be more damaged. But most of the heat was coming from the transistor itself, so I am suspecting weak drive to the base could have caused the transistor to be resistive.
The car does smell like gas when running. I don't know if that's a consequence of the valve or not.
Assuming a worst case Vce of 300mV at 500mA, that's 150mW. Easily done, unless there is a fault somewhere.
I think I will test the wiring by shorting the transistor pads through a 4R resistor and DMM, and see if the current is what is expected. For all I know the last owners might have sold the car after the purge valve fried the transistor and replacing it didn't fix the engine light.
The transistor itself is far more damaged than the traces leading to it. I would think if it were a direct short, the traces would be more damaged. But most of the heat was coming from the transistor itself, so I am suspecting weak drive to the base could have caused the transistor to be resistive.
The car does smell like gas when running. I don't know if that's a consequence of the valve or not.
Does the transistor have a back emf protection diode on it? If not that could have started the failures.
Doc
Oh! Honda Civic! Sluggish brain coming on line. I owned an 85 CRX that had a gas smell problem. Turned out there was a recall out to get a modified filler tube installed at the dealers. Check your model for recall status. Might get a free fix out of it.
Doc
Doc
Oh! Honda Civic! Sluggish brain coming on line. I owned an 85 CRX that had a gas smell problem. Turned out there was a recall out to get a modified filler tube installed at the dealers. Check your model for recall status. Might get a free fix out of it.
Doc
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It does, I just noticed that today. It has a 60V integrated zener from collector to base. I could perhaps obviate it by a putting a freewheel diode across the wiring harness of the purge valve, but I wonder if the valve could be hurt by the EM braking that might cause. So the question is whether the 60V protection point was set to protect the transistor or to prevent EM braking of the solenoid?
At any rate I made a weird but functional substitute and it seems to be fine. I guess the original problem has been addressed.
At any rate I made a weird but functional substitute and it seems to be fine. I guess the original problem has been addressed.
An externally hosted image should be here but it was not working when we last tested it.
https://instagram.com/p/5YNgdvmA-O/
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We lived outside all the time. We had our bedrolls rolled up in a tarp. If it was raining, we'd just cover up with our tarps and sit there. We'd bathe in the river. It was pretty cold sometimes. We lived on beef and pinto beans. The meat kept fine outdoors. It was a lot better than this Frigidaire meat, you bet. Down on the desert outfits, they made lots of jerky. I'd eat it with biscuits if they was good, or I'd just eat it straight. You didn't have many good bread cooks out in the camp. In the wintertime, we'd have them steaks for breakfast, and gravy. It was a pack outfit, so you didn't get eggs or anything like that. It had to be stuff you could pack, but I never got tired of eating the same thing all the time."
https://en.wikipedia.org/wiki/Tom_Blasingame
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What is better, a vane fuel pump or a turbine fuel pump? And how much will the pump behavior actually affect the engine?
Fewer sliding parts in the turbine pump will probably last longer as well as generate less debris.
However a vane pump may come up to pressure faster. I don't know whether this will affect the car while running, but it may put less stress on the starter for people who don't wait before starting the engine.
Fewer sliding parts in the turbine pump will probably last longer as well as generate less debris.
However a vane pump may come up to pressure faster. I don't know whether this will affect the car while running, but it may put less stress on the starter for people who don't wait before starting the engine.
Well, I replaced the fuel pump on our Corsica and now it finally runs. But it still puffs white smoke during idle that smells like gas and oil. I found an oily, crusty spark plug and sprayed WD40 in the cylinder to dissolve some theoretical varnish deposits breaking the ring seal, and while that made it a bit quieter it didn't change the smoke output. Smoke also comes out of the crankcase, oil dipstick and PCV valve holes, and the exhaust manifold. I was told the throttle was adjusted high because the O2 sensor was dead.
I would appreciate any advice.
I would appreciate any advice.
Do a compression test. Look for cylinder to cylinder differences. Record all cylinder readings, then test again giving each cylinder a squirt of 30 weight oil before testing it. If oil makes a big difference in compression, it's rings, if not, low compression is valve related.
You say smoke is white... This could be caused by a bad head gasket permitting coolant to leak into cylinders. Take a drive. Take foot off gas and coast down. Accelerate again. If this causes a short cloud of smoke that means a coolant leak into cylinders.
Best of luck
Doc
sounds like a broken piston ring or valve seal, causes what is called 'blow by'. A compression test should identify the cylinder. then you can do another compression check to determine which > the valve seal of coarse is cheaper to fix
First things first, you need to do a compression test to your engine. Do a dry test and a wet test.
A wet test requires you to squirt a little oil (at least a 20 weight 10w-30 works great).
Your cylinders should all be relatively the same within 10-15 psi of each other. If you have low compression in one or more cylinders perform the "wet" test. If your compression stays around the same or only jumps up 5-10 psi it is your cylinder head that is the problem. If your compression jumps 20+ points from the wet test then it is your piston rings.
First things first, you need to do a compression test to your engine. Do a dry test and a wet test.
A wet test requires you to squirt a little oil (at least a 20 weight 10w-30 works great).
Your cylinders should all be relatively the same within 10-15 psi of each other. If you have low compression in one or more cylinders perform the "wet" test. If your compression stays around the same or only jumps up 5-10 psi it is your cylinder head that is the problem. If your compression jumps 20+ points from the wet test then it is your piston rings.
MY grandfather told me to squirt WD40 into the cylinders, crank it a bit and wait for a while to dissolve cylinder gunk and re-seat the rings. How often is this the problem? And, wouldn't most people use carb cleaner instead?
The radiator fan doesn't come on for some reason. The dashboard temperature gauge also doesn't work. This would support the theory that the car overheated and something failed. The fan itself works, but it doesn't come on. There is a gasket between the lifter section of the engine and the middle of the engine. It has what looks like brown cooked on oil along it but it doesn't look like any recent drips. I don't know why there would be anything dripping through this seal because the oil never comes up that far anyways.
The radiator fan doesn't come on for some reason. The dashboard temperature gauge also doesn't work. This would support the theory that the car overheated and something failed. The fan itself works, but it doesn't come on. There is a gasket between the lifter section of the engine and the middle of the engine. It has what looks like brown cooked on oil along it but it doesn't look like any recent drips. I don't know why there would be anything dripping through this seal because the oil never comes up that far anyways.