When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
OK, first I have to tell you that I got called to Germany unexpectedly this week, so I don't have a lot of time. I am going on the Cam Am Caravan this weekend (check out the Great Lakes section as registration closes today) and I need some ideas on how to keep my car cool. Some facts: the engine is a freshly rebuilt 427/390; the radiator was recored at the same time; the water pump is original; the hoses are new and the lower has a spring to prevent collapsing; I'm running about 70/30 water coolant with a bottle of Water Wetter; I have a chin spoiler. When I run around town, or idle in traffic, the temp stays right around 190-200 without a t-stat. However, when I get on the freeway and cruise above 60 or so, the temp climbs to about 220-230. It would seem that moving more air would help cool the engine. I checked belt tension this weekend, and tightened the water pump belt. I have tried three different t-stats, Murray's special, AC Delco, and Accel, all 180. Nothing seems to work. Does anyone have any ideas for keeping this thing cooler? I'm the only C3 that's signed up to play with the new cars, and I don't want too much trouble. :D
well some people leave the seals out... (or find they are missing altogether) in that case theyll make a world of difference and itll run hot when at speed but not while idling (since that is handled by the fans....)
also what were you running with a 180 thermostat in there??? just curious... alotta people seem to be yanking them out...
I was running maybe 10-15 degress hotter at speed with the t-stat in, but only a little warmer when going slow. The Accel unit I bought had a huge opening in it. If I can get it cool at speed, I will try running without the stat in the summer.
This is probably not the case but worth a suggestion I suppose. During the rebuild did the crank pulley get replaced? If it was replaced with a smaller one your water pump won't be turning as fast.
Also, I've heard that freshly rebuilt engines do tend to run warmer for the first few hundred miles though 230 seems excessive.
hmmmm..... I have pretty much gotten my overheating under control, and in fact am about to compose a new topic listing the latest little tweaks. My problems were typically the reverse of yours: mostly ok on the highway but gets hotter in traffic or idle.
I will second the suggestion above about removing your front license plate. That made a surprisingly big difference for me. Also, as an experiment, take your car on the highway and as the temp guage creeps up try putting up your headlights (Either pull your override switch or just turn on the lights). The raised headlights allow more air to flow in - see if this reduces the temp at all. This one surprised me also; on a very hot day I got a noticeable movement in the guage after popping the headlights.
The removal of the front license plate bracket will make a big difference, as will the headlights (cool idea MJ), but the water pump could be the culprit. You said the pump is original. If it is binding or plugged anywhere, the water flow through the engine would be decreased and as with the crank pulley, would seem to be more likely to cause problems a higher RPMS (highway driving).
Thanks to everyone for the ideas. I have about 2800 miles on the rebuild now. I do have a front license plate, and will try removing it. I will also try the headlight trick. As for the water pump, it worked fine before the rebuild. I suppose I could have gotten some debris in it, but I was careful about it. Maybe some RTV got in there, I put a light coating on the front cover gasket and the two gaskets at the block. I would like to get an aluminum pump, but it would be nice to know if that's the problem.
For this weekend, I will double check all the seals around the radiator, remove the license plate, and try the headlights.
Thanks again, and keep the ideas coming if you have new ones. :cheers: