MackE7760 Posted December 19, 2021 Share Posted December 19, 2021 (edited) In general, if a cooling system is in good operating order(clean radiator, clean fins, good fan clutch etc), what kind of temperature differential should i be seeing from inlet to outlet with coolant around 200 (mid green area on my truck). Should t/d be higher if coolant is hotter(say 215)? Chasing an intermittent overheating issue. Edited December 19, 2021 by MackE7760 Clarification Quote Link to comment https://www.bigmacktrucks.com/topic/68949-radiator-temperature-differential/ Share on other sites More sharing options...
Joey Mack Posted December 19, 2021 Share Posted December 19, 2021 if youre truck is 06 and older (Gray Motor) the small green zone on the gauge is 180-185.. and I think you are looking for 30+ degrees difference between inlet and out let temps on the radiator, going in should be 180ish, 150ish coming out.. jojo Quote Link to comment https://www.bigmacktrucks.com/topic/68949-radiator-temperature-differential/#findComment-485536 Share on other sites More sharing options...
Joey Mack Posted December 19, 2021 Share Posted December 19, 2021 What model and year? what do you haul? what are the dust and dirt levels where you haul? jojo Quote Link to comment https://www.bigmacktrucks.com/topic/68949-radiator-temperature-differential/#findComment-485537 Share on other sites More sharing options...
theakerstwo Posted December 19, 2021 Share Posted December 19, 2021 I think if you cool your coolant 10 to 15 degrees your safe good. Quote glenn akers Link to comment https://www.bigmacktrucks.com/topic/68949-radiator-temperature-differential/#findComment-485538 Share on other sites More sharing options...
theakerstwo Posted December 19, 2021 Share Posted December 19, 2021 Freightliner manual with cummins says 10 with a hi flow engine and with a Big cam low flow you would cool as much as 45degrees. Quote glenn akers Link to comment https://www.bigmacktrucks.com/topic/68949-radiator-temperature-differential/#findComment-485540 Share on other sites More sharing options...
MackE7760 Posted December 19, 2021 Author Share Posted December 19, 2021 This is in a 2004 granite dump that tags a excavator (83000 gross when tagging) my gauge shows 200 as middle of green area, when in stop and go traffic in hot weather, she gets to 220ish(edge of red), but getting worse recently (red and alarm). Yesterday when troubleshooting, loaded around 50k, did two back to back acceleration runs and immediately stopped and checked d/t, only 10-12 degree differential between metal line going into radiator and bottom metal section going back to engine. One mechanic said need to be seeing 20+ d/t, but I thought i read 10 somewhere. Note that temp was probably 210 at this time, and the fan was roaring away BUT i could barely feel airflow between fan and motor. Took to shop and washed what I could, and it looks clean, but wondering if maybe between intercooler and radiator is plugged and i cant see it? Quote Link to comment https://www.bigmacktrucks.com/topic/68949-radiator-temperature-differential/#findComment-485544 Share on other sites More sharing options...
Joey Mack Posted December 19, 2021 Share Posted December 19, 2021 Nice posting.. I did forget about that style gauge.. Of course stay simple right now, are you able to see between the CAC and the radiator? maybe with a mirror or a bore scope? is it pushing coolant out of the reservoirs? is the fan shroud broken or missing? have you replaced the thermostats? you should have 2 on that engine.? Is it an ASET-I or 'C'? jojo Quote Link to comment https://www.bigmacktrucks.com/topic/68949-radiator-temperature-differential/#findComment-485545 Share on other sites More sharing options...
Onyx610 Posted December 19, 2021 Share Posted December 19, 2021 Probably the fan clutch, open the hood and rev the engine up watch the fan. The fan will look like it’s working good at idle. When you rev the engine it will slow down or almost stop if it’s bad. Quote Link to comment https://www.bigmacktrucks.com/topic/68949-radiator-temperature-differential/#findComment-485546 Share on other sites More sharing options...
Onyx610 Posted December 19, 2021 Share Posted December 19, 2021 30 minutes ago, Joey Mack said: Nice posting.. I did forget about that style gauge.. Of course stay simple right now, are you able to see between the CAC and the radiator? maybe with a mirror or a bore scope? is it pushing coolant out of the reservoirs? is the fan shroud broken or missing? have you replaced the thermostats? you should have 2 on that engine.? Is it an ASET-I or 'C'? jojo It’s a granite so AI unless there was some AC that I was unaware of? Quote Link to comment https://www.bigmacktrucks.com/topic/68949-radiator-temperature-differential/#findComment-485547 Share on other sites More sharing options...
MackE7760 Posted December 19, 2021 Author Share Posted December 19, 2021 Yes it is a AI-300A, yes, fan shroud is intact, when i did the two hard acceleration runs then stopped to check fan, it was roaring loud, like locked in through the viscous clutch, but really didn’t feel like it was moving air much. No, haven’t changed the thermostats (tomorrow), and im also thinking pull the intercooler to see if the face of radiator is stopped up (the radiator that i can see above the intercooler looks clean, but cant see between the radiator and the intercooler). I did notice today while trying to clean it from the front, when I sprayed through the condenser/intercooler, it sure seemed like a lot of the steam was coming out of the gap where I removed a shroud to try to see the rad face, like maybe where i cant see is bad, will pull it tomorrow (intercooler) to see face of rad 1 Quote Link to comment https://www.bigmacktrucks.com/topic/68949-radiator-temperature-differential/#findComment-485552 Share on other sites More sharing options...
Onyx610 Posted December 20, 2021 Share Posted December 20, 2021 Im assuming this is a cv712 six wheeler? Quote Link to comment https://www.bigmacktrucks.com/topic/68949-radiator-temperature-differential/#findComment-485554 Share on other sites More sharing options...
MackE7760 Posted December 20, 2021 Author Share Posted December 20, 2021 Close! CV-713 Quote Link to comment https://www.bigmacktrucks.com/topic/68949-radiator-temperature-differential/#findComment-485556 Share on other sites More sharing options...
MackE7760 Posted December 20, 2021 Author Share Posted December 20, 2021 17 minutes ago, Onyx610 said: Im assuming this is a cv712 six wheeler? Quote Link to comment https://www.bigmacktrucks.com/topic/68949-radiator-temperature-differential/#findComment-485557 Share on other sites More sharing options...
MackE7760 Posted December 20, 2021 Author Share Posted December 20, 2021 And yes Joey, i missed that, when it gets to red and alarm sounds, it is pushing coolant out then. Quote Link to comment https://www.bigmacktrucks.com/topic/68949-radiator-temperature-differential/#findComment-485558 Share on other sites More sharing options...
Onyx610 Posted December 20, 2021 Share Posted December 20, 2021 (edited) Under hp 10 wheeler in my opinion, if it’s pushing coolant it’s more then likely a head gasket or liners. Clearly check the easy stuff first. We had one with a bad fan clutch and rotted radiator and it was setting off the Alarm/Shutdown light. Guy still finished his 45 min long salt route with 15 tons of salt on and kept pushing the rocker switch to keep it from shutting down and never pushed any coolant out. Edited December 20, 2021 by Onyx610 Quote Link to comment https://www.bigmacktrucks.com/topic/68949-radiator-temperature-differential/#findComment-485560 Share on other sites More sharing options...
Joey Mack Posted December 20, 2021 Share Posted December 20, 2021 I know its a bit of work, but you can open the hood and stand in the opening and look,, can you take your pressure washer and blow the gap between the cooler and rad.? hell a garden hose with a small fire hose nozzel can do it..... you got this.... jojo Quote Link to comment https://www.bigmacktrucks.com/topic/68949-radiator-temperature-differential/#findComment-485561 Share on other sites More sharing options...
Joey Mack Posted December 20, 2021 Share Posted December 20, 2021 by the pic. you are in FL.. anyway keep it simple.. that truck is one of the last .... damn good Mack's... in my opinion.... Jojo Quote Link to comment https://www.bigmacktrucks.com/topic/68949-radiator-temperature-differential/#findComment-485563 Share on other sites More sharing options...
MackE7760 Posted December 20, 2021 Author Share Posted December 20, 2021 610, she is set/injected at 375hp, and with 206k/26k hours, I realize that it may be(likely) internal issues, but hopefully not. Jojo, thats what i did this evening. Theres a shroud that makes the cooling air go through the aftercooler instead of shortcutting to radiator, removed it and with motor running washed the radiator as best i could for a good while in my carwash. It wasnt hot enough for the fan to really pull it through but may help, we will see tomorrow. Btw, South Louisiana not Florida Quote Link to comment https://www.bigmacktrucks.com/topic/68949-radiator-temperature-differential/#findComment-485568 Share on other sites More sharing options...
Popular Post MackE7760 Posted December 20, 2021 Author Popular Post Share Posted December 20, 2021 Ok, update. Since i had felt minimal air movement behind the fan while the fan was roaring away, i was suspicious of a plugged radiator core. The top 6 inches not behind the intercooler looked good and a flashlight shined through good. But behind the intercooler no light passed, so we pulled the intercooler off.......probably 90% plugged behind the intercooler with dust/dirt and insulation (we are a demolition contractor). Spent the day blowing it out from the fan side, then washed it from both ways. We are gonna button her back up tomorrow and see if that was it. Ill be surprised if this wasnt the issue, will report back either way 5 Quote Link to comment https://www.bigmacktrucks.com/topic/68949-radiator-temperature-differential/#findComment-485609 Share on other sites More sharing options...
Joey Mack Posted December 21, 2021 Share Posted December 21, 2021 Yep..... I thought so... Git'r done.... jojo Quote Link to comment https://www.bigmacktrucks.com/topic/68949-radiator-temperature-differential/#findComment-485610 Share on other sites More sharing options...
MackE7760 Posted December 21, 2021 Author Share Posted December 21, 2021 That picture that looks Floridaly was on a job on the LSU lakes, deconstructed and demolished a early 1900s house out there. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/68949-radiator-temperature-differential/#findComment-485622 Share on other sites More sharing options...
Joey Mack Posted December 21, 2021 Share Posted December 21, 2021 That suck's!!! Quote Link to comment https://www.bigmacktrucks.com/topic/68949-radiator-temperature-differential/#findComment-485623 Share on other sites More sharing options...
MackE7760 Posted December 21, 2021 Author Share Posted December 21, 2021 1 Quote Link to comment https://www.bigmacktrucks.com/topic/68949-radiator-temperature-differential/#findComment-485624 Share on other sites More sharing options...
MackE7760 Posted December 21, 2021 Author Share Posted December 21, 2021 It was Condenmed due to rot induced structural failure, somebody has to do it🙂 1 Quote Link to comment https://www.bigmacktrucks.com/topic/68949-radiator-temperature-differential/#findComment-485625 Share on other sites More sharing options...
Joey Mack Posted December 21, 2021 Share Posted December 21, 2021 I know... still sad. lots of old houses here have the same fate.. Quote Link to comment https://www.bigmacktrucks.com/topic/68949-radiator-temperature-differential/#findComment-485639 Share on other sites More sharing options...
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