Cooling problems

[CST-30]

I have been having some cooling trouble on my 87 k-5 that has me stumped, the guage will rise all the way and drop back to normal stay there for just a minute and then rise to hot and fall back again, repeatidley, it will rise slow but fall back pretty fast, setting still its fine it just does this when driving, any ideas?

72 K-5 cst blazer 2 1/2 lift 33" bfg's
69 custom 30 longstepside 4x4 6" lift 36" directionals
87 K-5 stock

 

[BlueKnight]

Well it could be a sticking thermo-stat. i removed mine for just that reason. it could also be something with the water pump under load. It could be wearing out. You may also have a small clog in your radiator. Start with the T stat as that is an easy one.

<font color=purple>79' K-5 396cid 600hp, TH350, NP203</font color=purple>
<a target="_blank" href=http://blueknight.alloffroad.com>http://blueknight.alloffroad.com</a>

 

[NoSmog73]

I might be wrong but isn't the temp gauge elect. if so check for short in wires or bad connection at sender maybe (if I am wrong someone will correct me )

 

[chevydude]

my guess is the thermostat,i have had this happen to me SEVERAL times,same symptons

marcus

 

[TorkDSR]

it does sound like the stat. specially if its rising slowly and dropping quick. the gauge is also a good thought, but the readins would be much more erradic. and im assuming its a mechanical water pump.

beligerence doesn't justify intelligence.
<font color=blue>wheelers hate posers.</font color=blue>
<font color=red>79k15/400/700r4/205/38.5</font color=red>

 

[CST-30]

I have had them stick shut but never act like this, tomorrow I'll put on a new one and hopefully that will do it. Thanks Rob

72 K-5 cst blazer 2 1/2 lift 33" bfg's
69 custom 30 longstepside 4x4 6" lift 36" directionals
87 K-5 stock