heater specs
 

ok so i am making head way on geting heat back in my c20. new core rad water pump tstat (195) and no i didnt replace it all just for heat.

so i was thinking that alot of us seem to be haveing problems with heat and heaters so i would like some one with a good working system to take a few reading of temps. air temp out the defroster and floor vent. also the temp of the lines in and out of core.

i am thinking most of these truck run 195 stat. and the factory feed form the manifold and return to pump or rad.

i think if we can geet some specs on this it will help most of us alot. and help to find where are problem is faster.

also are there diff cores and blowers? see heavy duty and reg???

Re: heater specs
 

Heater core they get scaled up just changed mine think about it had water setting in it 35 yrs

Re: heater specs
 

I'm not sure about heavy duty or just regular cores or motors.I just got a regular core from napa couple years ago for my 86.I've said that for years with these trucks if the heating system is good shape,they will cook you out! Case in point,last year the first of March it was -45 deg C when I left home & five minutes down the road I was rolling window down a bit & turning the fan down cause it as getting too hot in the truck.....

Re: heater specs
 

I wonder sometimes if people mix the anti freeze right or just guess.
too much or not enough it can ice up.
even with cool air or close to freezing
A cheap tester to get...worth the 5-7$

Re: heater specs
 

Motor nut you might be onto something there too,I pretty much run 50/50 premixed in everything now.No prob summer or winter.

Re: heater specs
 

Black Friday antifreeze 50/50 1 gallon jug at PepBoys for $1

Re: heater specs
 

rubble could you get the temps form your trucks? thats how mine was back a few years ago before the core died. now its just crap but better then nothing. anitfreeze being the wrong mix i get but its 40-50 here and still crap lol

Re: heater specs
 

Cab condition and insulation also comes into play. My old plow truck used to have snow ice up on the bare steel floor, put in new rubber mat and insulation and the heat would blow you out. Provided the radiator was covered and allowed the cooling system to heat up.
Without the rad cover (in my case, just cardboard in front of it.) and 2 temp gauges, I could watch the thermostat "cycle" open and closed. Radiator could cool too much and drop the temp in the engine.

Re: heater specs
 

And the other thing it could be is a weak blower motor.They slow down in age and most never replace them tell they fully die out.

Re: heater specs
 

I will try this aft,otherwise it will be sat. It supposed to be around -20 to -25degC during the day so it should be a good temp test.

Re: heater specs
 

-20-25 gettin winters wrath early eh.
Can't complain here, we've missed all but 10cm, and that melted last weekend +18,+8 this weekend.
Fun for me is using the 79-2B 305 with no choke,and I'm sure no float lol.
Its all we used to move us.
Takes a bit to throw some heat,in a topless truck lol
Soft top is stashed in the house for the winter.
Hardtop is going on soon ...

Re: heater specs
 

Yep changed that also was still working new one blows twice as much air.

Re: heater specs
 

Ya,we are getting a blast of winter now.Was blizzard off & on today,not bad now just wind chill of about-30.We been lucky so far,better than last year at this time though.No bugs this way eh!!!
No choke would be fun trying to get that warmed up..

Re: heater specs
 

Just done my heater test about 1/2 hr ago,it was -28 degC last night & about -18 in the shed where my 86 sits.Pumped it 3 times & she fired right up,hard time getting tranny into neutral,bit stiff.It ran about 15 minutes,temp gauge up to normal (sorry no engine temps,battery dead on temp gun).Temp at heater duct was +45 degC(110F) & still climbing.Like I said earlier,when the heater system is in good shape on these old trucks,it WILL cook you out!! Also to those guys that ***** about carbs & hard starting,the old Rochester on this truck was rebuilt last winter & starts like a dream.Our local guy grew up on these trucks & can rebuild them in his sleep,cost me about $300 for his parts & labor..rant over

Re: heater specs
 

lol my qjet has been wired open for 8 years. hold the rpms at 1500 for 30-60 then she will run fine.

110?? out the vent after 15 min. what tstat do you have? if you know lol. mine i would say is no where near that at all more like 60 or 70 at best will check mine this week.

Re: heater specs
 

I'm thinking it's a 195, it's been a couple years since I replaced it.I would've grabbed some pics but thought about it afterwards & I'm pretty limited when it comes to posting unless the wife's around to help me!

Re: heater specs
 

I did my crew last year too,new core,blower motor & cleaned out mouse crap & canola...It works same way too...

Re: heater specs
 

i hear about the wife. same boat unless i get pissd and keep trying lol if you can at some point get that temp gun going too and see what is on and out. like i said just trying to get things right.

Re: heater specs
 

ok so now that i have been laid off i have been able to do some work on the c20. took my temp gun and after driving her at 55 for 10 min stoping at he shop the tstat was 142.7f the lines into the heater are at 130in 120 out. this is with a new 195 that i just put in when i did the water pump. think i need a new tstat and try again. as my dad 95 g30 at the stat was 185 in the same time

Re: heater specs
 

Measured the air temp at the heater exit. Was getting 120 with blower on high. Engine wasn't to full operating temp even after several miles of around town errand running. 27F outside temp. New heater core and 1 year old fan motor. 195 thermostat. It blows hotter if the engine if up to full temp.

Re: heater specs
 

yea i am only getting arount 80 to 90 vent temps. new state tonight i hope lol

Re: heater specs
 

ok new 195 stat and...........105 vent temps. wth am i missing? nothing seems hot but the heat lines you cant hold vary long. i am going to see what the vent temps are with an oild school thermometer and see what the air temps are over the casings for the air. even the top of my rad is 130 upper hose is 130 but the lines to the core are 150+ in??? will be rechecking everything soon and report back. thanks guys

Re: heater specs
 

Get some aluminum tape (not duct tape, the metal tape, like heavy tin foil with adhesive on it) and tape up the gap between the heater box and the defroster Y-tube. There is like a 1/2" - 3/4" gap there. Never understood it. Why would I want to heat under the dash? Maybe to keep gauges from fogging? Anyway, you can only get to three sides of it, the other side is too close to the firewall, but tape those three sides up to get full defrost.

Re: heater specs
 

think last time i had it out i did that but will check tonight. thanks