Keffer inc Posted August 12, 2019 Author Share Posted August 12, 2019 I think I see air bubbles coming up inside me coolant tank. I replaced that and it's clear where you can see inside of it and there's bubble coming up. If I choke the hose that supplies coolant to the system, the bubbles stop, so it's not just engine vibration tricking me I don't think. Bad to the dealer ship. This truck is a shop queen this month. Hopefully it's something they did wrong when it was there for an injector 1.5 weeks ago. Probably a injector cup? It definitely got worse since I got it back from them. Quote Link to comment https://www.bigmacktrucks.com/topic/58506-mp8-running-hot-up-hills-and-mountains/page/2/#findComment-429893 Share on other sites More sharing options...
fjh Posted August 12, 2019 Share Posted August 12, 2019 16 hours ago, Keffer inc said: Doing my first load since I replaced the water pump, thermostat, cleaner the radiator fins, changed the coolant filter, and the truck is running 210-215 with a 20 foot container with a 1 ton load on flat ground. It seems to have gotten worse. I noticed if I'm at a traffic light, it's coolant down to 200 when we get going and climbs back to 210 in a minute or two. Think it's possible it's an EGR blockage? I'm assuming these trucks have oil coolers, but not sure where they are located? It may be the egr cooler how ever it would likely be throwing an up an engine fault for mass flow! And it it don't normally cause over heating! Quote Link to comment https://www.bigmacktrucks.com/topic/58506-mp8-running-hot-up-hills-and-mountains/page/2/#findComment-429900 Share on other sites More sharing options...
Keffer inc Posted August 12, 2019 Author Share Posted August 12, 2019 If it was a failed EGR cooler, coolant should be in the outlet pipe right? Can't really go the other way can it? Meaning exhaust is going into the coolant system? Quote Link to comment https://www.bigmacktrucks.com/topic/58506-mp8-running-hot-up-hills-and-mountains/page/2/#findComment-429934 Share on other sites More sharing options...
Keffer inc Posted August 13, 2019 Author Share Posted August 13, 2019 EGR looks normal, no moisture. Quote Link to comment https://www.bigmacktrucks.com/topic/58506-mp8-running-hot-up-hills-and-mountains/page/2/#findComment-429974 Share on other sites More sharing options...
fjh Posted August 13, 2019 Share Posted August 13, 2019 13 hours ago, Keffer inc said: If it was a failed EGR cooler, coolant should be in the outlet pipe right? Can't really go the other way can it? Meaning exhaust is going into the coolant system? YUP Oh ya it can ! only 16 Psi in the rad 30 plus on the other side! Quote Link to comment https://www.bigmacktrucks.com/topic/58506-mp8-running-hot-up-hills-and-mountains/page/2/#findComment-429978 Share on other sites More sharing options...
Keffer inc Posted August 13, 2019 Author Share Posted August 13, 2019 37 minutes ago, fjh said: YUP Oh ya it can ! only 16 Psi in the rad 30 plus on the other side! Shouldn't coolant leak back while the truck is not running? Quote Link to comment https://www.bigmacktrucks.com/topic/58506-mp8-running-hot-up-hills-and-mountains/page/2/#findComment-429988 Share on other sites More sharing options...
fjh Posted August 13, 2019 Share Posted August 13, 2019 (edited) Usually Yes! In my opinion you likely got an injector cup issue how ever usually this is accompanied by a hard starting condition! But not always ! The same can be s said for the EGR thing 16 psi shut down may not be enough to leak coolant but 35 psi back pressure( may )be able to push back into the cooling system! unfortunately its a crap shoot! Remove the forward EGR tube and look right inside for trace amounts of coolant red or orange dots! Edited August 14, 2019 by fjh 1 Quote Link to comment https://www.bigmacktrucks.com/topic/58506-mp8-running-hot-up-hills-and-mountains/page/2/#findComment-430012 Share on other sites More sharing options...
Keffer inc Posted August 14, 2019 Author Share Posted August 14, 2019 Forward tube? Would that be exhaust inlet or outlet? I checked the outlet and it was dry and black soot as usual with no sign of dried coolant. But that was only checked on outlet. I too think it's a cup, it's just too coincidence that they just did an injector and the fact too that they said they had a hard time getting the old cup out that they needed to cut it out. Hope they didn't cut too much out that it needs a new head. Quote Link to comment https://www.bigmacktrucks.com/topic/58506-mp8-running-hot-up-hills-and-mountains/page/2/#findComment-430028 Share on other sites More sharing options...
Keffer inc Posted August 14, 2019 Author Share Posted August 14, 2019 The truck has a date with the dealer on Friday. Three weeks out of the month.. Its turning into a "shop queen". Sucks too, I wanted to quit my job and start with Mercer but can't do that if my truck isn't right and can't get a head ache rack because of all the expenses. If it is caused by work they did, do dealers usually warranty their work and fix it for free? Hopefully I'm not paying twice for the same part. Quote Link to comment https://www.bigmacktrucks.com/topic/58506-mp8-running-hot-up-hills-and-mountains/page/2/#findComment-430030 Share on other sites More sharing options...
JoeH Posted August 14, 2019 Share Posted August 14, 2019 Probably depends how well you can leverage your anger at them. Quote Link to comment https://www.bigmacktrucks.com/topic/58506-mp8-running-hot-up-hills-and-mountains/page/2/#findComment-430035 Share on other sites More sharing options...
Keffer inc Posted August 19, 2019 Author Share Posted August 19, 2019 (edited) Truck is at the dealer. Today they ran regular diagnostics to figure why it's over heating. They said they cant find anything wrong and want to check the water pump and make sure it has the correct tolerance and not slipping. I think its wasting time but I told them they could check it. The only other guess is that the radiator is plugged up so they will replace that I guess if the pump good to them. Anyone else have any other guess or anything maybe they should look into? Edited August 20, 2019 by Keffer inc Quote Link to comment https://www.bigmacktrucks.com/topic/58506-mp8-running-hot-up-hills-and-mountains/page/2/#findComment-430449 Share on other sites More sharing options...
fjh Posted August 20, 2019 Share Posted August 20, 2019 (edited) 14 hours ago, Keffer inc said: Truck is at the dealer. Today they ran regular diagnostics to figure why it's over heating. They said they cant find anything wrong and want to check the water pump and make sure it has the correct tolerance and not slipping. I think its wasting time but I told them they could check it. The only other guess is that the radiator is plugged up so they will replace that I guess if the pump good to them. Anyone else have any other guess or anything maybe they should look into? Nope were not there ! They are! let them do what they need to eliminate things unfortunately there are no magic bullets when chasing this stuff just educated guesses! rule out in order of the cheapest to the most expensive ! They may even have to revisit already plowed ground Hard to say! Water pump easy enough ! You may end up doing all Six cups! Ya just don't know! the symptoms are not really cup symptoms how ever ( coolant push Usually ) Edited August 20, 2019 by fjh Quote Link to comment https://www.bigmacktrucks.com/topic/58506-mp8-running-hot-up-hills-and-mountains/page/2/#findComment-430484 Share on other sites More sharing options...
Keffer inc Posted August 20, 2019 Author Share Posted August 20, 2019 Tomorrow I'm bringing a loaded trailer to hookup with a tech riding shoot gun to watch live data while the truck is in action. Everything they looked at passes so hopefully this will reveal something. Gonna name the truck "Shop Queen" in the shop 4 out of 5 weeks. Quote Link to comment https://www.bigmacktrucks.com/topic/58506-mp8-running-hot-up-hills-and-mountains/page/2/#findComment-430520 Share on other sites More sharing options...
Popular Post Keffer inc Posted August 23, 2019 Author Popular Post Share Posted August 23, 2019 Looks like it was a plugged radiator. Tuesday we hooked a loaded trailer to the truck and a tech rode along with a laptop to check the coolant and oil temp, as well as the fan on-off command and percentage speed of the fan. All of that was working right but still had higher temps going over the bridge. So we all finally agreed to change the radiator and see if that was the problem. Looks to me like it's almost completely plugged up. They should be done with it today. 1 1 1 1 Quote Link to comment https://www.bigmacktrucks.com/topic/58506-mp8-running-hot-up-hills-and-mountains/page/2/#findComment-430669 Share on other sites More sharing options...
fjh Posted August 23, 2019 Share Posted August 23, 2019 Thats good or bad news which ever way yo want to view it! how ever at least ya can work instead of being camped at the dealer. is that pic bottom or top? Quote Link to comment https://www.bigmacktrucks.com/topic/58506-mp8-running-hot-up-hills-and-mountains/page/2/#findComment-430676 Share on other sites More sharing options...
Keffer inc Posted August 24, 2019 Author Share Posted August 24, 2019 That's the top. They said the inside of the motor looks good with no large peices of rust. So I think this fix will last for a little while. 1 1 Quote Link to comment https://www.bigmacktrucks.com/topic/58506-mp8-running-hot-up-hills-and-mountains/page/2/#findComment-430752 Share on other sites More sharing options...
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