Will turning the smoke screw in cause the coolant temperature to raise in the truck? How about the starwheel? I know it will raise EGT's but how about the coolant temp. My truck has started running hotter than normal when towing a trailer. It is not in the overheat range, but it is towards the high end of normal range and I don't like that. It started this winter, so had my radiator flushed and installed a new non cycling thermostat. But it still gets warm like before I did that. My pump is not turned up that much and I am running a open air filter, so I know I am getting good air flow in. My next thing to do was replace the radiator. Do you all have any suggestions on what to try. Maybe backing the smoke screw and starwheel back out some? O, by the way when it gets warm, I can let of the go peddle and it will start to fall back down fairly quickly.<br><br>Thanks, Bill

 

If your fuel setting is too agressive, you will run hotter. If EGT's are up, the surrounding metal heats up too including the water.<br><br>For towing a simple adjustment to the star wheel should help out in this department. Upping the spring pressure would reduce the fuel at the higher boost pressures from towing. <br><br>I have also found that I had a plugged up screen in front of the intercooler that the previous owner had in. After I pulled all that out when I fixed my rad, it runs way cooler and the needle never moves even with the AC on and towing at 8-9 psi boost. <br><br>Also another thing to check is your timing.. Timing that is retarded will also give you higher running temperatures.<br><br>J-eh

 

You said this was only a problem when towing. Have you checked your transmission and cooler. Might be getting hot and transferring heat to the radiator. Maybe it's done some slipping since turning the pump up. Could have debris starting to get in the system. Just thinking out loud here

 

I have checked all the above. Tranny is not slipping, it has a recent overhaul. I think I am going to replace the radiator and waterpump. Just because at 230,000 it wouldn't hurt anything. I am going to do them one at a time though and see which one if either is the culprit. Bill

 

Bill,<br><br>Hopefully I didn't missread your post but for what it's worth, the smoke screw will make virtually zero difference in temps, both water and EGT's.<br>The smoke screw provides an ever so slight downward preload on the AFC and is only in the equation for the first couple seconds/60' or so.<br><br><br>Bob.

 

Your truck is now 10 years old and chances are that the radiator will have some pretty serious deposits and will show up as excess heat when towing. Like Lil Dog said the coolant is the heat dispersant for the engine, if you were to lose 20% cooling running empty the guage at 70F outside probably would not be noticable. Pulling a load at summer temps would show up as retained heat (guage not dropping quickly) as others have mentioned the system becomes less efficient. Blocked cores like bugs and dirt, AC on and poor coolant flow (internal blockage) will compound the problem along with extended fuel pulling= more heat continous will result in a hotter maintained reading on the guage. If the truck tows a lot and you have to get the rad done or replaced have an extra row added to the core, costs money but will never regret the cost as it is a lot cheaper than engine. PK