van overheating

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travlin man and wife

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2011 chevy express 2500. 300 miles  ago I changed hoses, thermostat new antifreeze. every thing was fine fore 300 miles and then she overheats.  Was able to make it to a piolet and changed thermostat because it is possible to get a bad one and that was a good place to start out on the road But that did not fix it. even though it is hot their is no hot air from heater and top hose is soft no fluid moving through it.   I now suspect it is the water pump. I hate to pull all of that stuff off again. I got the van towed back home and I can do the work but it is cold hear in tn. Any body have any other suggestions I would appreciate them. I think I might change clutch fan so I don't have to go back in at a later date. The systems has 200,000 k on it. I also changed belts and all the idler pullies when I did the hoses.
 
It may be unlikely as you just changed everything out and didn't notice anything wrong, but it's also possible the radiator is clogged up. I've had it happen. Good luck with it. Overheating sucks
 
If everything was fine before you changed hoses and the thermostat I'd say there's air trapped in the system.

Assuming it's got a v8 since it's a 2500, this is from ls1techs:
**Bleeding the system of air:
Start it up and let it run, radiator cap OFF, and let it warm up till the t-stat opens. I rapidly squeeze the upper and lower radiator hose like 20 times while its warming up to help move any air bubbles through the system and by the t-stat on the engine side. When the t-stat opens you’ll see the level drop as you squeeze it, its sucking the coolant through the system. You will also see the coolant start to flow in the radiator fill neck, once it starts to flow the level should drop down a lot, immediately top it off with coolant/water. Then the flow will stop when the t-stat closes. Wait one more time for the t-stat to open again and start to flow, if it drops down again top it off again. Do it a 3rd time if you want to make sure. I always massage the upper hose during the whole process to keep any air bubbles moving through. Always works like a charm. Just keep checking your temp gauge until the t-stat opens for the first time to make sure it’s not sitting there overheating from a trapped bubble. May take 10-15 minutes for the t-stat to open the first time.
If you do start to get hot while sitting there and the t-stat will not open…..you have an air bubble on the engine side of the t-stat. Shut the engine off and rapidly squeeze the upper and lower radiator hoses again. Then start the engine again and see if the t-stat will open. Sometimes you just have to work those hoses to move the air through. Even after it seems topped off after a couple cycles…check it the next time you have a cold engine…top off if needed.
 
I would also not discount another bad thermostat. the cheap junk ones they sell you at the parts store are just that, cheap junk. get a factory thermostat. it sounds like the water is not circulating so that points at a clogged radiator, stuck thermostat, or a broken water pump shaft/impeller.

note,
water pumps just don't stop circulating water unless the shaft breaks(pretty obvious) or the impeller comes off the shaft(very rare but not impossible).

radiators don't plug up overnight, this is a long slow process.

you could always pull the thermostat and see if that gets the upper hose and heater hot. don't leave it that way but that will tell you for sure the thermostat is bad.

highdesertranger
 
Thanks for all the help. HDR you are right about thermostat the first one came from the dealer I seen the difference the last time I changed it. The dealer one the copper core and springs are 3 times bigger than the parts house one. the one I installed on the road came from a parts house but it is not likely I would get two bad ones.  remember I drove it 300 miles before this happened. If it was a air bubble it would have shoed up before then. But I will try the bubble remover technique before I take it apart again. HDR I cant remove thermostat because the gasket is part of the thermostat unless I destroy one of the thermostat so I can use part of the frame to support the gasket. Mabey I could make a gasket to go between the flanges just to check it out. Also it has ben refiled 3 times not likely I would have bubbles  with the same exact tine frame before   overheating.
 
It's a pain in the butt but you can test the thermostat. Info pasted below. (I don't know what PPE is)

Test Procedure
The thermostat needs to be out of the car and on the bench for this.
The temperature at which the thermostat opens is usually stamped on the thermostat itself. In the absence of such, a technical manual or parts supplier will require referencing.
Appropriate PPE is strongly recommended as this test involves boiling hot water.
  • Place the thermostat in boiling water¹:


    • if the thermostat opens, this confirms the thermostat is able to open
  • Remove the thermostat from boiling water²:


    • if the thermostat returns to the closed position, this confirms the thermostat is able to close


¹ - remember that the temperature of boiling water varies with altitude; it's 100 °C at sea level
 
PPE = personal protective equipment.
 
It's cheap to get the engine dye checked.  If it overheated it could be an issue with a head gasket or cracks...  The dye reacts to combustion gasses in the coolant.  Nothing you can do will solve a bad head gasket or crack other than a high-dollar fix.  Assuming the dye checks out kosher then you can spend money chasing other avenues...
 
Please let us know how this misadventure turns out. It is very instructive to learn what those mysterious causes were.
 
Doubleone said:
It's cheap to get the engine dye checked.  If it overheated it could be an issue with a head gasket or cracks...  The dye reacts to combustion gasses in the coolant.  Nothing you can do will solve a bad head gasket or crack other than a high-dollar fix.  Assuming the dye checks out kosher then you can spend money chasing other avenues...

A serious combustion chamber leak will produce bubbles in the coolant.  When faced with a high dollar estimate, 2 kilobucks plus heads if necessary, I tried Bars head gasket sealer.  It worked, the car is still in service.  That was 3 years ago.  Here's the old thread with other people's comments and opinions worth reading. 
https://vanlivingforum.com/showthread.php?tid=21782

This is the product I used.
https://www.amazon.com/Bars-HG-1-Blown-Gasket-Repair/dp/B003RGIWO0/
 
Did you notice if the thermostat had a bleed or "jiggle" hole to help bleeding/burping?  Some drill a bleed hole if not on the replacement.

https://agradetools.com/tip-2/

My preferred technique is to remove a topside hose on the upstream side and look for flow with the engine running and up to temperature. Some radiators allow a check for flow when looking down into it with the cap removed. You can see the water flowing.  Placing your hand on the top hose when cold and feeling for heat helps identify open thermostat/hot water flow.

A restricted radiator will sometimes cause the bottom hose to contract or be easier to squeeze due to water pump created vacuum.

Heater cores can become restricted.  You can remove the return hose and check for flow when hot and running.  If restricted, sometimes with both hoses disconnected, placing a water hose nozzle and blowing water in both directions will clean it out.
 
My ex-mother-in-law had an overheating problem in their decommissioned Penskey Savanah. I helped them with diagnosing and decided the best bet was to change the water pump. Turns out, in the process of doing that job, it was simply an issue of being low on coolant. a leak in the dumb plastic hose attachments, the ones with the little retaining clip (which was not connected right).

Someone mentioned air in the system. I would start there since you just refilled the coolant.

If not that, I'd to the block tester for a Head gasket leak. you can "rent" one from the auto parts store.

Here's my favorite car guy, Scotty Kilmer, explaining how to do it.

Also, as mentioned previously, you can take off the radiator cap (when the engine is cold) and run it. As it heats up, try revving the engine to see if there are bubbles. Scotty explains all of this well.

I hope that it is not a head gasket.
Good luck

Chris.
 
The old red Ford (in my profile) blew a head gasket as I was driving from NC to WV and the temp gauge was showing hot and cold air was coming out of the heater.   The engine was sucking in the water thus removing the coolant from the cooling system.  

I stopped by a K-mart and purchased this plastic water container and filled it after filling the radiator and running the engine till the heating was working again.   I also bought a can of radiator stop leak and added it.  It slowed it down some so I then released the radiator cap so the cooling system wasn't pressurized. (so the coolant wouldn't be sucked into the engine as it ran)   It was enough to get home.

I agree with looking to see if there is a bleeder valve in the cooling system.  If the air isn't bled out the Temp Gauge may read hot.....but even at that you should have heat coming from the heating.  

The worst case I've ever seen was a free wheeling impeller in a water pump which was working intermittently.  That was diagnosed when looking into the radiator to see if coolant was flowing or not.  

Sometimes hoses break down inside and it causes a blockage so fluids won't flow thru them.   But I think you've alrea eliminated that issue.
 
UP date took every thing apart and flushed system. looks like in might be a clogged radiator. don't know what could have clogged it but it happened fast. Will start to take it apart tomorrow . A new one will be about $250.00. have not checked with dealer probably about $500.00. Rock auto is $248.00. About the same as OReilly So probably same one come from china.
 
travlin man and wife said:
UP date took every thing apart and flushed system. looks like in might be a clogged radiator. don't know what could have clogged it but it happened fast. Will start to take it apart tomorrow . A new one will be about $250.00. have not checked with dealer probably about $500.00. Rock auto is $248.00. About the same as OReilly So probably same one come from china.
Don't forget to look at the Pick and Pull junk yard option if your funds are tight.
 
travlin man and wife said:
Rock auto is $248.00. About the same as OReilly So probably same one come from china.

Those cheap rads with plastic tanks have trans cooler connections that are much flimsier than the OEM fittings.

You might consider adding an oversize trans cooler and use that only and not plumb through the one in the radiator.

That setup makes it easier if you ever need to pull the radiator again (like with a cheap aftermarket rad).

Adding a magnetic inline filter is a good idea,too IMHO
 
Update when the van first overheated the lower radiator hose was off. I had just replaced the hose and chevy does not use a clamp on the radiator neck, they pot a grove on the neck and a slip on hose with a grove on it you slide hose on neck and then put a three point contact wire clip in the grove. I think my original problem was I did not get the hose on correctly an it stayed on for 300 miles. After we put the hose back on and filed with antifreeze it still over heated so I changed out thermostat and filed with antifreeze again still overheated again. So I thought water pump was bad so put on new pump still overheated again. So at this time I started doing some thinking and decided to take top radiator top hose off and started engine and got no liquid from hose. SO took one gallon and pored down the hose put it back on started engine. problem solved.     I have probably changes antifreeze a 100 times in the last 50 years since I started driving and never had a radiator that would not back flow when filed. So a heads up to anyone changing that hose be shure you get the hose on and the clip on correctly. and you may have to fill top hose manually.
 
Yeah, I don't think anyone had asked if you had coolant loss. Might want to invest in a Mityvac cooling sytem pressure tester. Or they can be rented from auto parts stores.

I'm curious about what a "three point contact wire clip in the groove" hose clamp looks like. I'm only familiar with old Dodges (and now a Ford). Glad you got it sorted out!
 
So the top hose was filled with air..... lol Check the level in the radiator again in a week or so in case any more air got pushed out.

Glad you got it sorted out!
 
good to hear you got it all sorted out without spending time in a repair shop.
 
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