Truck heating up

[suladas]

Here’s pics of inside rad. I pulled all rad hoses too and they were fine also.

 

[Truck Shop]

What was the highest temp reading on the gauge? Did it ever push coolant past the cap? Does it
have a shunt hose from top tank to thermostat housing that's in good condition?

 

[suladas]

What was the highest temp reading on the gauge? Did it ever push coolant past the cap? Does it
have a shunt hose from top tank to thermostat housing that's in good condition?

This week since the issue started 190 was the highest, that's the temp when the light comes on so I turn the fan on. No doesn't push coolant out past cap. Yes that hose looks in really good shape, as do all the hoses.

 

[Truck Shop]

IMO-you may as well put it back together at this point. What is the thermostat rated at temp wise- 195* or 205*?
Use a infrared gun and check temp at front of cylinder head just behind stat housing. You have checked most
all of the common boxes.

 

[suladas]

New one is 180, old one I was told was 180 so I kept it the same. Will do.

 

[Coaldust]

Was the sneaky water regulator metal backed rubber seal still intact?

 

[suladas]

Was the sneaky water regulator metal backed rubber seal still intact?

Is that the seal by the thermostat that separates the two compartments? If so it looked fine. I got a new one though.

 

[Coaldust]

 

[Coaldust]

A cool trick to see if your regulator is working good is to look at the wear mark on the regulator. The wear mark should measure 3/8” and be nice and shiny. And if the wear mark is missing, the seal is missing or messed up.

 

[Coaldust]

Too bad I wasn’t closer. I could have it diagnosed in 1 hour including the time for coffee. I might only charge you travel, because you appear to be a cool
Guy. You own a B model, so you must be cool. You are cool, but apparently your engine is not so cool.

 

[Coaldust]

Diagnosing over heating 3406B’s is the only things I’m good at. Trained by the best. Hundreds of hours of Caterpillar marine, EPG, earthmoving , truck and industrial cooling system diagnostics. One time, Cat Truck engine analyst credentials. Like a cooling system whisperer.

Spent years neglecting my health, family and friends to help other people keep their crap running and profitable.

Sitting in my single-wide with a labradoodle ,sh$t posting on the HEF with you guys on a Friday night because you are the only friends I have.

I’ve explained the cooling system troubleshooting process numerous times on the HEF. But, nobody listens.

Put it back together and purchase a infrared thermometer and a can of flat black spray paint. Report back and I’ll walk you through it.

 

[Truck Shop]

ut it back together and purchase a infrared thermometer and a can of flat black spray paint. Report back and I’ll walk you through it.

I guess we've been told.

 

[Mobiltech]

What did the oil cooler inlet face look like ? Clean?
Or like this one?

 

[Coaldust]

Wow. That’s super gross. Brown sludge from hell.

I get it. Shops can bilk a lot of time from their customers for overheat issues and never find the root cause. Its very easy and non-evasive to measure water in, water out and water mix temps on a 3506B. Forget about water mix. Make it super easy and check water in and water out. According to the tmi data, that engine has a 12F degree temp rise. So, there should be a 12F degree drop across the radiator.

If the Delta T is more than 12F, it’s a flow problem. If the Delta T is less than 12F, capacity problem.

At least, you have a general idea where to look before taking stuff apart .

According to Caterpillar SIMS data, the last time I had access, overheating was 60% of warranty engine complaints. In the dealer world, we focused resources on technician development in that area.

 

[suladas]

Diagnosing over heating 3406B’s is the only things I’m good at. Trained by the best. Hundreds of hours of Caterpillar marine, EPG, earthmoving , truck and industrial cooling system diagnostics. One time, Cat Truck engine analyst credentials. Like a cooling system whisperer.

Spent years neglecting my health, family and friends to help other people keep their crap running and profitable.

Sitting in my single-wide with a labradoodle ,sh$t posting on the HEF with you guys on a Friday night because you are the only friends I have.

I’ve explained the cooling system troubleshooting process numerous times on the HEF. But, nobody listens.

Put it back together and purchase a infrared thermometer and a can of flat black spray paint. Report back and I’ll walk you through it.

Sounds like a plan. At one point I did question why I didn't have the guy who I share shop space with do it for me, but I do generally enjoy fixing my own stuff and learning more about it. I've never had a overheating issue before so it's a first for me. I've replaced a water pump once that dumped the coolant out, and a thermostat when another truck wouldn't heat up, both easy straightforward stuff but that's my extent of working on them.

 

[suladas]

Oil cooler did not look anything like that picture, I didn't look too closely at it but there was only minor dirt on it.

 

[Delmer]

I'm going to say we all failed at this one. 190 is not overheating in any way. Measuring the radiator temperature will tell you nothing because we can't be sure the thermostat is open at 190, if you had 210, then the thermostat would be open and you could see what's happening. It could be that the old thermostat just started working correctly, hadn't been closing all the way before.

 

[suladas]

I'm going to say we all failed at this one. 190 is not overheating in any way. Measuring the radiator temperature will tell you nothing because we can't be sure the thermostat is open at 190, if you had 210, then the thermostat would be open and you could see what's happening. It could be that the old thermostat just started working correctly, hadn't been closing all the way before.

Yes at 190 overheating is the wrong word, but regardless the thermostat would be opening before that being a 180 and even at 190 it would sit at that temp and not move without the fan on, even with the fan it took forever to drop and last week driving it it was immediately noticeable how much quicker it would heat up and not cool down. The only reason it didn't see much higher temps is because it was like 10F outside. The light comes on just before 190 and fan kicks itself on around 190.

 

[mitch504]

Your overheat light comes on before the fan does?

In my(sub-tropical) world, 190 isn't an overheat. Mack service manuals used to say that a diesel engine should run 100 degrees above ambient temperature. They even gave the example of a truck crossing the desert.

 

[mitch504]

Your overheat light comes on before the fan does?

In my(sub-tropical) world, 190 isn't an overheat. Mack service manuals used to say that a diesel engine should run 100 degrees above ambient temperature. They even gave the example of a truck crossing the desert.