Can anybody tell me if I have to pull the dash or can I access the heater core replacement through the engine side of the firewall? Will the A/C lines be an issue?

Thanks All,

The Pilot

 

I believe that you can get to it without removing the entire dash on the 1st gens. Not like the 2nd gens anyway.

 

You don't have to remove the whole dash, but it does take quite a while.

Really good writeup with pics:
http://www.sytyarchives.com/howto/vi...imate_controls

 

Thanks for the link LeeAnn! I'll prob. need it sooner than later. Lots for me to learn as it is going to fuel injection, and all these on-board computers, sensors and other technical crapola!---LMAO!!! So any time I can save fixing a heater core is GREATLY appreciated!--- *wink*

 

As it is a common problem with our trucks. It seems we have so much torque, that on those special occasions (ie. boost launches) the motor rotates under the hood enough to stress the hoses going to the heater core. This can bend and irritate the solder joints on the core, causing it to ooze a warm, moist gym locker fluid all into your carpeting in your pristine cockpit.



1)- Make sure your new heater core is the same. I got mine from Advanced Auto for under 30 dollars. GM wanted A LOT more. Ivan got his from Trak Auto for about the same. Adam and Brian of FAST got theirs from Pep Boys.
2)- Transfer the foam insulation to the new heater core
3)- Cover ends of the new heater core to prevent debit from entering it
4)- You may want to bend the tubes of the new Heater core to make it easier to install
5)- Everything above... in reverse


did he just tell me to bend the tubes on the new heater core, which is why I am replacing the heater core, because the tubes got bent and caused a pinhole leak where the tubes are soldered onto the core????

not trying to be an a$$hat or anything, its just that I just did my 93 heater core, and did not have to bend the tubes to fit....it was a tight fit, but it went in.........now my 85 looks like a whole new ballgame....

 

I don't know - I didn't bend mine to fit on my '93. I just ignored that step

 

Uh This is a job I did on my blazer. swore I would never do one again. Take it to a mechanic that has done one before. If the charge is less than 150 buck labor - hire him.

 

what ever you do dont take it to a dealership, i had to the 1st time mine broke, 800$ then the damm thing let go less that 2yrs later, so i changed it in my driveway, 3days in the snow, a tip of advice if your doing it yourself take the passenger seat out helps alot

 

no, but do remove all of the screws/bolts holding it in (defroster vents, under the lower corners of dash, center support brace at trans hump), it makes the HC come out much easier on an A/C truck)

[quote=hotrod413;255446]As it is a common problem with our trucks. It seems we have so much torque, that on those special occasions (ie. boost launches) the motor rotates under the hood enough to stress the hoses going to the heater core. This can bend and irritate the solder joints on the core, causing it to ooze a warm, moist gym locker fluid all into your carpeting in your pristine cockpit..............................did he just tell me to bend the tubes on the new heater core, which is why I am replacing the heater core, because the tubes got bent and caused a pinhole leak where the tubes are soldered onto the core????

not trying to be an a$$hat or anything, its just that I just did my 93 heater core, and did not have to bend the tubes to fit....it was a tight fit, but it went in.........now my 85 looks like a whole new ballgame....[/quote]

do what i did on my '92. drill a hole straight down (top to bottom) through the frame right beside the alt. install an eyebolt (weld it closed or you'll pull it apart), and run a 3/8 chain up to the rear of the alt bracket (the steel one on the back of it). drill a hole, bolt it in using washers on both sides of the chain, and you're done-forever! **MAKE SURE CHAIN HAS NO SLACK IN IT!**
i had replaced 3 driver's side mounts in 5 months before i had figured this trick out. guess the 5+ grand launches in 4HI aren't really friendly to motor mounts, nore is power shift @ 7 grand into second (also explains why i broke so many tranys, hahahaha!).
your '85 is really no different from your other truck.

it's not that difficult, really. i did my first one the last weekend in January (many years ago) in a parking lot @ a car show. had towed my brother's Summe truck down to SpeedORamma, and the core puked-and i mean puked!, as i was pulling up to the building to unload. i had to do it exactly 1 year and 2 days later since i DIDN'T pull all the dash bolts, and bent the tubes (i figured, since it leaked from the joints the second time). see the post by hotrod413 above, and you'll see what i mean.

only if you like having the two pointed studs in the floor digging into you. your choice, but not necessary.

 

I replaced mine about a year ago on my 94 s10 blazer, took me about 45 minutes. When mine went up it threw antifreeze all over the inside of the windshield cause the defroster was on, what a mess.