Questions on Thermostat Replacement Procedure and Brand
 

Joe, been thinking about replacing the thermostat but have been leaning toward the "if it ain't broke, don't fix it" school of thought. As both you and Alfred testify to the importance of this item I'm reconsidering it. Also, my conclusion that the radiator cap was the fix may have been mistaken.

Must admit that I've been influenced by the Haynes Integra and Legend Repair Manual which combines the instructions on thermostat replacement for both models. It states that one must drain the radiator fluid before replacing thermostat but then goes on to describe the part's location on the Legend as next to the lower radiator hose and the one on the Integra as next to the distributor. To get to the point, draining the rad fluid when i changed the radiator was a messy affair (without a lift) and this has influenced my desire to tackle this project.

Can anyone comment as to whether it is necessary to drain the rad fluid when replacing the thermostat on this model? I believe Autozone rep said it's not necessary and its position on top of the engine block (my recollection?) suggests that he may be right in his claim that this is a simple procedure on this model.

Autozone rep also suggested the Failsafe 170 degree (OEM spec) thermostat over the OEM part because it is designed so that in the event of failure it will always fail in the open position. Have always preferred OEM items but if there has been a design improvement since the car was made then perhaps this is an exception. Any suggestions on Failsafe thermostats (or any other brand) versus OEM? Based on the MotoRad's certification of ISO 9001 and the automotive standard of QS 9000 I'm inclined to believe that this is an exception to the OEM rule.

Here's a couple of links describing the Failsafe part http://www.autozone.com/autozone/cat...dName=Failsafe
http://www.motoradusa.com/products/f...rmo/index.html

The thermostat is always one of those cheap insurance items. I've never looked much into a fail-safe one, I've always just used OEM.

As to draining, I'm fairly sure you should drain the radiator, but just the radiator. The t-stat housing should be high enough that you don't need to drain the block. Does you new rad not have a drain petcock on it?

maybe water and coolant mixture is not correct.

Lynxs, was persuaded by your "cheap insurance" argument. Purchased a Motorad Failsafe 170 (OEM rec'd temp) and will try to get it installed soon.

Cruz, I took care to get the proper water/coolant mixture. However, as stated earlier, I only changed the fluid in the radiator as I could not loosen the engine drain bolt. Perhaps there was a difference in the new coolant mixture I added when I changed the radiator and the fluid in the engine block.

After replacing the t-stat will hopefully be able to post a successful conclusion to this matter.

Thanks all!