MackE7760

Ok, computer logged low coolant level, and some injector codes(eup?) Seems my driver forgot to tell me he added coolant yesterday. pressurized cooling system and found a leaking hose behind the blue silicone extended “T” hose, gonna pull her down, flush her out, and change that hose and see if we have any more issues. Thanks for the assistance on this one, JT

And to make it worse, it’s running fine now. Will check the coolant sensor and plug this afternoon, maybe the cold(cool to most of you IK) made for a bad connection? Got someone trying to see if computer logged the shutdown

Truck is in South Louisiana, temp was in the 50s at start

This morning, checked oil and coolant, both good, cranked right up, 10-15 seconds later, shutdown. Double checked, all good, started again, 2-3 seconds later, 60+ oil pressure, ice cold temp, shuts down. Restarted and kills again (red shutdown light), even with override. Does shutdown system use a different o/p sending unit than gauge? Any ideas? Ran great yesterday 11 hrs

But yea, didn’t think about oil

Whats the clutch interval on a 4500 RDS?

Imma dig into it more, but i dont understand what the detrimental effect would be if the entire output assembly were pulled out, and a plate were machined to close up the opening that was where the output assembly previously resided. Maybe im missing something here.

Dang! Not at all what i was hoping!

That is the present game plan, pull it and see, but was hopeful that maybe someone on here had “been there, done that” before that could give me tips for potential pitfalls

Is anyone familiar with the direct drive (always running/nonstop) pto that is mounted on the flywheel housing? 04 CV713, ex cement mixer truck converted to dump, with the dump pto transmission mounted. Im wanting to remove the direct drive pto and install a cover plate and oring where the pto was....it rattles LOUD! At an idle, the gear lash rattle is louder than the engine, annoying! I check with my dealer for a blockoff plate, and was told non exist. If i were to remove the pto, is there any reason I couldn’t make a plate with the same bolt pattern on it, and just cover the opening with a new oring? Btw it is mounted at about 10 o-clock on the bellhousing looking from the rear of truck. Seems simple from a machinist/engineer perspective BUT i havent seen what its like in the flywheel housing. Any ideas?

Ok, we did this recipe on our 04 Granite, and are pretty happy with the results. With 26k hours on the motor, one hole a little lazy in the morning till well warmed up, and a bit more oil consumption than i like, we are considering a inframe. There is a shop not too far that has a mack guru that we are told can do it right with the dry, non oringed sleeves. Contemplating a cam change at the same downtime to eliminate the egr bump all together. If we were to do the cam.... A. What cam recommended B. What lifters(same?) Any other suggestions?

Ok, I promised a final report.... Yesterday in 75 degree, stop and go Baton Rouge mid day traffic @ 83k lbs, temp got close to, but never reached, 200 (mid gauge). Once out of traffic and stabilized, about 185. Im sure the reduced airflow through the radiator, and the additional heat from the converter not locked in the traffic attributes to the higher temps. I feel that we can call this temp issue resolved. Thanks for the advice, as always, this forum is a wealth of knowledge for the mack owners.

It was Condenmed due to rot induced structural failure, somebody has to do it🙂

That picture that looks Floridaly was on a job on the LSU lakes, deconstructed and demolished a early 1900s house out there.

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

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

And yes Joey, i missed that, when it gets to red and alarm sounds, it is pushing coolant out then.

Close! CV-713

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

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?

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.