Help!!! Thermostat, water pump or something else???

[sewlow]

When you put H2o in the rad, make sure that the rad cap is the highest point of the cooling system. Park facing up a bit of a hill. I've have probs with both my trucks with air-locks after replacing heater cores & other stuff related to the cooling system. Especially the one with A/C. Keep the engine running as you fill the rad, adding more wtaer as the system burps the air out. My A/C truck can take about 20 mins. to a 1/2 hour to get all the air out.
And yes, I also think that this is a thermostat issue.
Also, check your rad hoses. Grab 'em & squeeze. If they feel 'crunchy' inside, like their full of cornflakes, you may want to do a cooling system flush. That crud in the hoses is also plugging up the heater core & the rest of the system.

 

[TwoPedal98]

Well checked the coolant level again and was still down a little, added some let it run till the thermostat opened (right at 170) and got quit a bit of air out of it had to add some more, ran fine on the drive home, I'll check it again when it's cool and see where it's at, hopefully it's good oil looked and smelled good!
Thanks for the input guys, I would've started with the thermostat

 

[Mik3]

It sounds like it could be an air pocket, possibly low on coolant. So top it off and leave the cap off to let air out. I don't know if there's a hose on the thermostat housing but if there is, follow it to the coolant reservoir and pull it off until it squirts coolant, plug it back on(With engine running). If that doesn't do it, I would suspect the water pump, no heat means no hot coolant going to the heater core which leads me to believe if no air is in the system, no coolant is being pumped. Get a gasket and pull the pump off and have a look, see if the fins are eaten up by rust. A gasket isn't even necessary, most people use RTV(Even me, on water pumps only though). I seriously doubt it's the thermostat, when they get stuck, they usually get stuck and don't open ever again(Yours is opening because the engine wouldn't cool down at all if it was stuck for good). Throw that in some hot water on the stove and see if it opens. Don't just start replacing , check if it actually needs to be replaced, and you'll save money! And on another note, DO NOT run your truck with no thermostat, you'll prematurely wear internals. Your engine needs to be at operating temp for everything to be expanded properly.

 

[TwoPedal98]

Well finely had time to take a closer better look and it looks like it's time for an intake gasket!

How hard are these to change? I do all my own maintenance and external engine, and drivetrain repairs, is this something I should dare to try, I've switched out intakes on old carbureted small blocks how much more complicated is it?

 

[shelbyt.67]

Its not complicated, just a PITA. No diff than carbed really. I did mine couple mnths ago and it took a couple-a-three hours. When u get the new gaskets, toss the supplied sealant in the garbage. Use a premium rtv sealant. I like Permatex ultra-black.

 

[oohunter04oo]

Its not complicated, just a PITA. No diff than carbed really. I did mine couple mnths ago and it took a couple-a-three hours. When u get the new gaskets, toss the supplied sealant in the garbage. Use a premium rtv sealant. I like Permatex ultra-black.

i would definitely recommend GM RTV Sealant! Its the best RTV in the world!

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But the intake isn't that bad of a job. I've even seen ppl label each connector and/or take pics of everything. just a little advice!

 

[Gamikatsu]

Hondabond is pretty good stuff too.... Permatex ultra black, GM RTV, or Hondabond. stay away from offbrand stuff, your engine can't afford it!

 

[ChrisAU]

Its not hard, but do make sure you make a good fat bead of good RTV on the back and front walls of the block, they don't line up quite right and I had an oil leak a few weeks after doing mine!

 

[TwoPedal98]

Thanks guys! Don't think I'll have time to tackle it this weekend so I'm hopping to do it the following one, any thing else I should plan on replacing while I have her ripped apart? She's got 133k on her

 

[shelbyt.67]

Heater hose connector. Usually break on removal and impossible to put back without it leakin. I temp repaired mine with rtv but I need to replace it. There's an upgrage I found that is better, but I can't find it right now. I'll look fer it.