Rednucleus

93 5.7l Suburban. Intake mani gasket and heater hose quick disconnect were changed in 2003. Noticed this week coolant is leaking around the white quick disconnect/hose connection (back of motor next to distributor). Looks like the metal part screwed into the mani was changed in 03 and is fine. So, before I bust something, thought i would ask:
1. how to work this gizmo
2. does the hose have an insert that snaps in to the quick disconnect?
3. any o rings?
4. any magic tools needed?
Thanks for you input!

Rednucleus

LOL I am shocked and dismayed at you guys! 135 views and not one response so far. This is supposed to be a part that commonly fails so I assumed I would get a pretty quick response from all you "smarter than me" guys. Oh well, I will continue to patiently wait (maybe have another scotch).
Thanks in advance for your help!!

tech2

lol...no help for you!

I'm not familiar with 93's. post a pic of the problem.

Rednucleus

So, turns out the metal fitting screwed in to the manifold was leaking. If you do a search for Chevy heater quick disconnects you will see lots of videos on how nicely these cheap metal fittings deteriorate and snap off leaving threads in the manifold. The fitting was literally oozing coolant under pressure. I tried an extractor tool (Lisle #62200) made specifically for this problem - it bit in well but ultimately the material was so deteriorated it continued to break apart. So I used a cut down hack saw blade to cut 4 notches (as seen in multiple UTubes) and knocked the debris out with a hammer & punch; shop vac'd debris from manifold. Next tapped manifold with 1/2-14 NPT and replaced the problem quick disconnect with a standard hose nipple & hose clamp. Before connecting hose back to heater system I started it up with hose over side of hood to hopefully flush any remaining debris out. I will close this thread with a big "Thank you" to whoever decided this part made more sense than a standard hose clamp. I'm sure it was used to make assembly easier - save a nickel per car in labor - but would be nice if they used decent material. There is an aftermarket direct replacement made of good metal but I personally like the good old hose clamp.

Rednucleus

A little more help please.
When I started this repair I also finally changed the lower coolant sensor for the gauge (not the upper one for computer) since my gauge has been reading low for years. Gauge now runs 220-240. Upper hose firm pressure, too hot to hold for more than 5 seconds. Lower hose comfortably hot to hold. Heater hose from intake manifold (part I just replaced) nice and hot but easy to squeeze like not much pressure. Heater works fine, doesn't seem excessively hot. No "hot" smells to motor. Radiator purges normal amount to reservoir.
Maybe given wrong sensor? Debris from drilling/tapping affecting thermostat?
Hate to hassle changing thermostat. I don't have a Temperature scanning tool.
Unfortunately I did not save old sensor or box and did not drive it right after changing before I did the work listed above. Live & learn!

Rednucleus

Final update - My smart mechanic neighbor said change thermostat. Took his suggestion and for the 1st time in years the gauge quickly comes up to operating temp and varies 180-210. Put old thermostat in boiling water and it barely opens a crack. So for who knows how long, I have been running the bad combo of a dash gauge reading cold, and a thermostat barely opening at operating temperature.

tech2

Mechanic neighbours are awesome.

if you had a new vehicle it would have told you to replace the thermostat!

Newer vehicles have a rationality check for the thermostat. It will set a p0128 dtc is the temp sensor is not at a predetermined valve after a set run time.

Rednucleus

Who needs a computer when you have a smart neighbor. Just went for another big drive and all is excellent. Hopefully good now for another 350K miles!!

tech2

probably going to have better fuel mileage and cleaner engine oil now too!

Cusser

I used the green one/size on our 2005 Yukon 6.0

https://www.oreillyauto.com/detail/b...ct+tool&pos=16

https://www.oreillyauto.com/detail/b...ect+tool&pos=0