My truck let me down today....

[Kyle M.]

My cousin and I decided to go do some snow wheeling today since it was getting warm out and the snow was melting down, we figured it was good to go. It is amazing what the trucks can go thru. I was pushing snow with the front bumper and it just kept on going, that was awesome.

But as we kept going I noticed my truck was getting hot so I got out and checked the radiator, belt and fan for snow and it was all clear. So we decided it get going on our way out figuring I wasn't moving enough to cool it down but first I let mine cool down. After a bit we took off and right away it warmed up again so I stopped, but this time the overflow was full and I could hear the coolant boiling. Again, we let it cool down for 10 min or so and got out on the road heading to my house. Once I got on the road it was cooled off so I drove it home. I got home and poped the hood to check it out, and again the coolant was boiling, but the temp gauge was in the middle. So I let it cool down for about and hour, went out and took the cap off and all the hoses where flat with suction and the overflow was still full. So at this point I took the cap off and filled it up with some coolant cut it was was way low. I took it for a quick spin and it got warm quick so I went back home and checked it out and the hoses were really hard like it had a lot of pressure in them. So at this point I decided to remove the stat thinking it was not opening and just leave it out. So I did that and now it seems to be fine, but I boiled the stat and right at 195* it opened up like it should...WTF. Why did this happen, I wasn't beating on my truck, running 4 low in second gear running about 2500 rpms. It just has me wondering now, was it just a chain reaction from initially getting warm or was the stat bad or something else....any insite would be appreciated, thanks for reading my long post.

 

[grey ghost]

possibley an air pocket somehow?

 

[rurouni20xx]

change the thermostat and hoses (weak hoses can collapse and cause this problem) and check the water pump flow, if its fine and it still does it pull your plugs and check for water blowing out as this is a sign of a blown head gasket. the pressure in the cylinders is pushing thru the cooling system blowing all the coolant into the tank and really driving the pressure up, ive seen it happen one time b4 on a mitsubishi. hope that helped.

 

[Kyle M.]

I think I got the air pocket after it boiled the first time, but how it got to that point in the first place, I don't know

 

[rurouni20xx]

loose clamps on lines, leaking thermo gasket or blown head gasket(s)

 

[Kyle M.]

No leaks so I think I can rule out and loose clams or bad stat gasket. As far as the blown head gasket, I had that thought, that is why I pulled the stat. Afer that i let it run with the cap off for a while watching for bubbles in the radiator, and I didn't see any. I also saw that the water pump was flowing very good. I took it for a 10 min drive after i took the stat out, it didn't get warm(didn't think it would and I know I shouldn't run without it, just didn't have time to get a new one yet, but i will) But I took it for a drive figuring that if I had a bad head gasket, i would get the pressure again and fill my overflow, but it didn't and it seems like everything was alright. Even after I took it for a drive, I let it sit and idle for about 30 min and still nothing unusual. Must be a bad stat, but the stat is less than a year old and when I boiled it in a pan on the stove, it opened when it was supposed to.

 

[chittybangbang]

Did you have snow packed on your radiator?

 

[Kyle M.]

Nope, everything was clear...that was my first thought

 

[grey ghost]

there might have been a speck of rust jamming the thermostat shut?

 

[MikeWild]

Well it did get you home, so in theory, it didn't let you down!


Good luck with the diagnosis.

 

[Kyle M.]

Well it did get you home, so in theory, it didn't let you down!


Good luck with the diagnosis.

Yeah, I should change the title to it "almost let me down" But it did shorten the fun I was having

Next weekend I am going to go hit it hard(if it is running good), we will have a melt all this this week, should be fun!

 

[Copytech]

If your overflow tank is full and your hoses are collapsed from suction, your radiator cap is bad. It is not allowing coolant to reenter the radiator from the overflow bottle.

 

[Kyle M.]

If your overflow tank is full and your hoses are collapsed from suction, your radiator cap is bad. It is not allowing coolant to reenter the radiator from the overflow bottle.

That is what I was thinking, but if the cap was bad, how it it let the coolant out in the first place? That seems like a reasonable idea, but would it just go bad like that? I have never had any issues in the past.

 

[cocoasranger]

A weak spring in the cap will let the coolant boil at a lower temperature and let it travel out into the recovery tank. I would get the highest quality cap and thermostat I could find, and replace the suction hose to the water pump with one that has a anti-collapse spring inside it.

Also won't hurt to test the thermo hub fan to make sure it has resistance and is working.

 

[Copytech]

Read this: http://auto.howstuffworks.com/cooling-system7.htm