The acetone my wife uses to remove her nail polish removed it quickly and easily.
Blower box sealer
- Thread starter JD1964
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I'm also a proponent (and user) of 3M strip caulk. That would be my recommendation. Especially if you ever have to take it apart to replace the heater core or evaporator core.
I’m working on the blower wiring too. Question, the blower switch has 4 settings. Low, m1, m2 and high. I have action in all positions except low. The blower should move in low too right?
I have new resistor. Next I’ll check and clean all connections.
Any ideas why the blower doesn’t spin in the low switch setting?
I have new resistor. Next I’ll check and clean all connections.
Any ideas why the blower doesn’t spin in the low switch setting?
If it doesn't spin on low, either the resistor is open or the motor has enough drag to stop it. The 3 low speeds are thru the resistor pack, and the high runs off the relay straight to battery feed.
GM originally used a die cut foam gasket and a seam sealer that cured to a very hard texture causing it to crack. You will find most leaks on a 78-88 A/G body are from the water seeping in to these cracks. They definitely did NOT use butyl to seal the box and I would not recommend using it to do so as it gets very messy if you try to use a solvent on it........it certainly will destroy a nicely painted firewall should you ever need to remove it.
The 3M strip caulk is the best item for the job and it will actually last a lot longer than butyl tape. Any of you guys that have any kind of 60's era GM product will see GM used it around kick panels and to seal holes holding door hardware to the inner door and inner body. I have pieces of it from several 65-66 model Chevrolets and it is still pliable and tacky enough to reuse (not that I do). But I am using new 3M strip caulk on my Grand National and my 78 Malibu. It is easy to work with and does not get messy like butyl.
The 3M strip caulk is the best item for the job and it will actually last a lot longer than butyl tape. Any of you guys that have any kind of 60's era GM product will see GM used it around kick panels and to seal holes holding door hardware to the inner door and inner body. I have pieces of it from several 65-66 model Chevrolets and it is still pliable and tacky enough to reuse (not that I do). But I am using new 3M strip caulk on my Grand National and my 78 Malibu. It is easy to work with and does not get messy like butyl.
Connections all cleaned and tightened. New resistor, no open paths. The blower switch in the head unit is pretty sloppy. Wiggling it can get intermittent functioning on the higher settings. Still no action at all on low.
I’m thinking the switch might be the culprit causing no action on the low setting. Anyone agree with me on this? If so, I’m hoping I can somehow repair the switch rather than replace it.
I’m thinking the switch might be the culprit causing no action on the low setting. Anyone agree with me on this? If so, I’m hoping I can somehow repair the switch rather than replace it.
I've never seen a failed GM fan switch, but that doesn't make it unpossible.
Are you getting voltage?
Are you getting voltage?
Timely discussion, thanks for the advice. I have to replace a heater core over the Holiday. Looks like the 3M strip caulk is the winner. Don't even need the kid at O'Reilly's to have to ask for 'make and model'.
Ok I think I got it figured out. First of all I had been powering the harness with a battery charger since the car is in a state of disassembly for an ongoing motor swap (94 Z28 LT1 + 4l60E).
Anyway, the battery charger did not have enough voltage so the resistor would not let enough current through to spin the blower motor on low speed. Hooked up a real car battery and got it spinning in low, but still encountered intermittent action in all speeds except Hi.
Problem recognized > blower relay has a bad path on the through circuit (dk blue), the one that passes power through to the blower motor from the various resistor speeds. Checked that path with an ohmmeter (relay removed) and the reading is dancing all over the place. So, I have a new relay on order.
BTW, in studying the schematic and running tests I now have learned that the low speed is always on whenever the ignition key is in the run position, even when the head unit slide control in the off position. Am I correct in concluding that this is the way it's designed?
Anyway, the battery charger did not have enough voltage so the resistor would not let enough current through to spin the blower motor on low speed. Hooked up a real car battery and got it spinning in low, but still encountered intermittent action in all speeds except Hi.
Problem recognized > blower relay has a bad path on the through circuit (dk blue), the one that passes power through to the blower motor from the various resistor speeds. Checked that path with an ohmmeter (relay removed) and the reading is dancing all over the place. So, I have a new relay on order.
BTW, in studying the schematic and running tests I now have learned that the low speed is always on whenever the ignition key is in the run position, even when the head unit slide control in the off position. Am I correct in concluding that this is the way it's designed?
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