2nd Gen Ram Tech 1994-2001 Rams: This section is for TECHNICAL discussions only, that involve the 1994 through 2001 Rams. For any non-tech discussions, please direct your attention to the "General discussion/NON-tech" sub sections.

Driving without bypass tube -- did coolant not circulate?

Thread Tools
 
Search this Thread
 
  #1  
Old 03-13-2019, 05:11 PM
Krellen's Avatar
Krellen
Krellen is offline
Registered User
Thread Starter
Join Date: Nov 2018
Posts: 14
Likes: 0
Received 0 Likes on 0 Posts
Default Driving without bypass tube -- did coolant not circulate?

Few months ago I replaced my water pump, but the heater bypass tube was completely corroded and wouldn't come out. I went ahead and put the new water pump in and filled the system up with distilled water, but unfortunately I could only get the system about half full before it started to pour out of the the inlet hole for the bypass tube.
There was an AutoZone with the part about a mile and a half down the road, and figuring I had enough water in the system to keep it cool for a short drive went ahead and drove over.
Thermostat reached a max of 210 when we got there, but I'm not sure if it was accurately measuring temp since the system was low. While there was no smoke, steam/water started coming out of the return hose from the heater core right as I pulled into autozone.
I drove the truck for a few weeks after this and didn't seem to have any problems, (It's in storage now) but I'm still kicking myself for doing that. My guess is that the pump wasn't actually circulating any water since the system was only half full/pump was sucking air through the heater core return hole. Hopefully I'm wrong? It was a cold night out, probably high 30's, and the drive only took about 5 minutes, but I'm paranoid that I might have damaged something. What do you guys think?

5.9 v8 magnum 46re trans
Already asked this earlier but was hoping for further clarification
 

Last edited by Krellen; 03-13-2019 at 05:31 PM.
  #2  
Old 03-13-2019, 06:40 PM
HeyYou's Avatar
HeyYou
HeyYou is offline
Administrator
Dodge Forum Administrator
Join Date: Apr 2010
Location: Clayton MI
Posts: 80,681
Likes: 0
Received 3,171 Likes on 2,924 Posts
Default

Bad idea. Pump likely was sucking air, and that doesn't cool the engine well. Is there damage done? Gonna have to do some troubleshooting to find out. Pressure test the cooling system, see what happens. Checking for combustion gases in the coolant would be wise as well. Make sure the oil isn't contaminated.
 
  #3  
Old 03-13-2019, 06:54 PM
MoparFanatic21's Avatar
MoparFanatic21
MoparFanatic21 is offline
Legend
Join Date: Nov 2014
Posts: 8,032
Received 306 Likes on 298 Posts
Default

I agree very very bad. You could of blown your head gasket(s) ruined a part of the cooling system, or warped the heads. Do the tests HeyYou mentioned. It wasn't circulating any water.
 
  #4  
Old 03-13-2019, 07:37 PM
Krellen's Avatar
Krellen
Krellen is offline
Registered User
Thread Starter
Join Date: Nov 2018
Posts: 14
Likes: 0
Received 0 Likes on 0 Posts
Default

Ugh, yea I don't know what I was thinking. The coolant is clear and the oil was not cream colored as of my last oil change. I'll have to pressure test the cooling system when I pick it up. Haven't felt a loss in power, seen any white smoke in the exhaust or noticed it burning oil. I'll stick a boroscope into the cylinders as well, see if I see any scoring. Any chance I got away without breaking something?
 

Last edited by Krellen; 03-13-2019 at 07:51 PM.
  #5  
Old 03-13-2019, 07:55 PM
MoparFanatic21's Avatar
MoparFanatic21
MoparFanatic21 is offline
Legend
Join Date: Nov 2014
Posts: 8,032
Received 306 Likes on 298 Posts
Default

Originally Posted by Krellen
Ugh, yea I don't know what I was thinking. The coolant is clear and the oil was not cream colored as of my last oil change. I'll have to pressure test the cooling system when I pick it up. Haven't felt a loss in power, seen any white smoke in the exhaust or noticed it burning oil. I'll stick a boroscope into the cylinders as well, see if I see any scoring. Any chance I got away without breaking something?
Anything is possible
 
  #6  
Old 03-13-2019, 10:13 PM
Krellen's Avatar
Krellen
Krellen is offline
Registered User
Thread Starter
Join Date: Nov 2018
Posts: 14
Likes: 0
Received 0 Likes on 0 Posts
Default

Even with a drive that short? The engine was almost totally filled with coolant, it just wasn't circulating-- not to mention it was a cold night.
 
  #7  
Old 03-14-2019, 12:01 AM
MoparFanatic21's Avatar
MoparFanatic21
MoparFanatic21 is offline
Legend
Join Date: Nov 2014
Posts: 8,032
Received 306 Likes on 298 Posts
Default

Originally Posted by Krellen
Even with a drive that short? The engine was almost totally filled with coolant, it just wasn't circulating-- not to mention it was a cold night.
Like I said anything is possible. Got could have done no damage or could have done a lot. I personally overheated these engines plenty of times and still drive 10+ miles with no damage.
 
  #8  
Old 03-14-2019, 11:58 AM
Krellen's Avatar
Krellen
Krellen is offline
Registered User
Thread Starter
Join Date: Nov 2018
Posts: 14
Likes: 0
Received 0 Likes on 0 Posts
Default

Last question then I'm done -- under normal conditions if you were to disconnect the return tube from the heater core, would coolant spray out? I'm still trying to gauge if the pump was circulating any water at all -- it's a pretty powerful pump so I'd think as long as the water level was reasonably high (which it was, pump was filled up to the level of the inlet hole) it would still pump water even while sucking air. But the ultimate tell is that no water came out of heater core return tube even with the heat set to full.
 
  #9  
Old 03-14-2019, 12:07 PM
MoparFanatic21's Avatar
MoparFanatic21
MoparFanatic21 is offline
Legend
Join Date: Nov 2014
Posts: 8,032
Received 306 Likes on 298 Posts
Default

Originally Posted by Krellen
Last question then I'm done -- under normal conditions if you were to disconnect the return tube from the heater core, would coolant spray out? I'm still trying to gauge if the pump was circulating any water at all -- it's a pretty powerful pump so I'd think as long as the water level was reasonably high (which it was, pump was filled up to the level of the inlet hole) it would still pump water even while sucking air. But the ultimate tell is that no water came out of heater core return tube even with the heat set to full.
Yes coolant should come out
 
  #10  
Old 03-14-2019, 12:23 PM
Krellen's Avatar
Krellen
Krellen is offline
Registered User
Thread Starter
Join Date: Nov 2018
Posts: 14
Likes: 0
Received 0 Likes on 0 Posts
Default

Was my temp gauge reading totally off in this situation since there was no coolant circulation?
 


Quick Reply: Driving without bypass tube -- did coolant not circulate?



All times are GMT -4. The time now is 06:50 AM.