new guy needs help bad!!!

[woodcock27]

hey guys i have a 2000 frontier 3.3 i just did a headgasket of it last week the truck runs great the problem is i have no heat and its running alittle warm but here is the thing i jacked up the front end filled a sealed funnel half way ran the truck kept squeezing the bottom radiator hose trying to bleed the air out of the cooling system and nothing so i read to put the cap on rev it with heat on high to 3000rpms for ten sec then return to idle shut off let cool refill and repeat i did this jacked up front end and i got heat so i figured great test drive pull out of driveway with great heat i get about 500 ft up the road the truck starts to run hot about 3/4 up the gauge then i lose heat and it runs normal temp i tryed bleeding the system again same way and got heat again i let it run in my drivway for 45 mins the whole time great heat take it up the road same thing starts to get hot i loose heat
i dont see any bleeder screws but the t stat and the bottom hose is cold feels emptyi gently slid the bottom hose off where it meets the stat houseing and i barley get coolant out of it at first like it was empty but i have repeated this aswell a few times same result can someone please help me i need this vehicle badly

[PedalBiker]

I have a Gen 2 so maybe I'm missing something. I had a bubble in the heater core once. I think if you can park steeply nose up it might help.

It sounds like a bubble somewhere. If there is room keep adding fluid/running the engine/shutting it down and refilling and you should work it out.

[speedfoos]

Just open the cap and let it run (in your driveway) until the thermostat opens with the heat on full blast.

Did you make sure your thermostat was good?

[woodcock27]

o i had it running in the drive way with the front end jacked up heat on high for like 45 mins but as soon as i drive it the gauge goes up and then i lose heat the guage drops
t stat is new

[speedfoos]

And you installed it correctly? Not trying to be an arse, but sometimes we do boneheaded things without realizing it. If the bottom hose stays cold that sounds like a thermostat related issue. Whether its faulty, installed incorrectly or blocked (by either a squibbed gasket or a glob of RTV). I would start there. While a pain to remove, I would pull the thermostat, test it (in a pot of boiling water) and go from there.

Not sure what to tell you as it sounds like an air bubble but you're doing everything to ensure that it works it's way out of the coolant circuit.

[PedalBiker]

It's been a while since I've seen a thermostat, but don't they usually have at least a small bypass hole so that you don't need to rely on them opening up to fill the system?

[CanNissan]

Originally Posted by woodcock27

o i had it running in the drive way with the front end jacked up heat on high for like 45 mins but as soon as i drive it the gauge goes up and then i lose heat the guage drops
t stat is new

Hi: woodcock27... Can you pressure test your rad cap? My 2010 owners man. calls for a new cap at about 30,000 mi. I can't understand why other than they're so small and may fail!!!
CanNissan N.S. of Lake Erie

[woodcock27]

i dont have a small enough adapter to check cap t stat was installed with the spring into the motor

[woodcock27]

three times now i have had heat then lost it the last time as i had said i left it jacked up running heat on high for about 45 mins then let it down left the driveway with good heat got about 500 ft gauge went up lost heat gauge came back down if i continue to drive it after the gauge drops back to normal and i lose heat it seems to start to rise up again but i didnt go far enough to tell if its going to fully overheat but bottom hose still ice cold

[speedfoos]

Bottom hose cold = thermostat. Bottom line. It's just a matter of why on the thermostat.