| Moderated by: Greg Fletcher | ||
| Author | Post | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
|
skoska Member 
|
My heater was not working sicne I bought the car last May and I decided to replace the thermostat. I bought a new one from Delta, installed it and now the engine temp is running hotter than it was before I replaced the thermostat, i.e., the temp indicator used to run about a quarter of the the way and now it moves directly to middle. Any ideas? Steve Koska 73 JH Rock Hill, SC |
|||||||||
|
Harkes Member 
|
Hi Steve, I don't see how a new thermostat could make your heater work all of a sudden. The cabin heater is operated by a valve in the bulkhead. When opened, fluid comes in from your inlet manifold. (regardless whether the thermostat is in "open" or "closed" mode) and goes out via the heater-return hose that runs all the way to the front - waterpump. your temp reading with the new thermostat sounds better with the needle in the middle (little to the right of the middle?) then with the old thermostat and the needle only a quarter of the way. you seem to have been running the engine too cold for most of the time. There are thermostats available with different temperatures readings. When the engine fluids reach the temperature that is stamped on the upperside of the thermostat, the thermostat opens so that cooling fluid finds it way to your radiator and then gets cooled. you can get a Hi temp - 82 C and a Low temp - 74 C thermostat. seems like your old one was a 74 C and your new one a 82 C. it all depends on your climate. When temperatures on average are over 30 C then a 74 C thermostat could be a better solution. Where I live temperatures just reach the 30 C very occasionally, so I run with a 82 C thermostat and then the needle is in the middle ...where it should be. Question: does your heater now function? If not, then most probably it is clogged in the heater box or the lines somewhere or your heater-valve is none-operative. I had exactly the same problem as you a year ago. In my case the very end of the HEATER-RETURN hose that goes all the way to the front was clogged and also where it was connected to the aluminium T-piece (close to the waterpump), it was also clogged in the small fitting. I cleaned the hose and t-piece (it was really stuck!!) and i had heating in the interior! hope this helps erik Last edited on 02-26-2007 09:29 am by Harkes |
|||||||||
|
edward_davis Member 
|
If the heater valve breaks, it's most likely to break in the 'open' position. It's operated by engine vacuum, and when there's no vacuum, its springs hold it open. Si if it freezes after a long period of non-operation (Which never happens to Jensens, right?), it will be stuck open. Also, if the vacuum lines are leaking in some way, it will be stuck open. Steve, I'm sure you checked this first thing, but I just have to mention it because I've bypassed the leaky heater core on my JH. Make sure that the PO hasn't bypassed the heater, with a sneaky loop of hose behind the engine; if it is, you might want to go ahead and tear down the console to get the heater core worked on, since it probably was leaking (hence the bypass). If your hoses check out, and you don't have any blockages like Harkes, you'll probably have to tear it all down to get the heater core out, anyway. They don't make them anymore, so you'll have to find some old-school radiator person who will rebuild it for you. That's exactly why I haven't bothered with it yet. I get enough radiant heat from the engine and exhaust, anyway.... Edward |
|||||||||