Anyone have ANY part number for the freakin' hose coming out the waterpump, running under the altenator/tensioner? It's a 3/4 hose, and I can not find a preformed one ANYWHERE.

 

Hoes don't act right. It's hoes on a mission and it's hoes on a crackpipe!

Er, uh, anyway, dump that preformed crap, throw the metal lines into your neighbor's yard, and just run straight 3/4 and 5/8 hose back to the firewall. Nice, cheap, and you can put metal braided sleeve covers on them like I did.

Just make sure they don't hang low enough to touch the exhaust manifold; once, I burned a pinhole into one of mine because that happened.

 

Tom, Dowards talking about the retun line to the waterpump from the heater control valve area. That does have special tension onit to keep from contacting the belt as it tucks behind going back to the WP.

Doward, Thats a return line from the heater core so the waterpump does not cavitate and the pump doesn't strain from too much pressure forced into a closed thermostat- this allows a constant flow circle of water. The one coming out from under the TB on the bottom intake manifold is the out flow towards the heater solinoid.

Only thing I can suggest is an A/C Delco dealer, or a dealership. Don't know if someone like autozone would have that.

 

I actually just went out and popped the hood to check the clearance. You can definately get away with just using 3/4" hose (about 2" length) off the metal line under the heater control valve. Then use a 90* double barbed brass fitting for 3/4" hose, then another aprox 1 1/2' of 3/4" hose back to the pump.

2' - 3/4" hose
4 - hose clamps
1 - 90*3/4" barbed fitting

 

Oh that's right, you guys are post-86, and have that stupid plastic/fiberglass heater valve. While you're at it, dump that piece of junk out too! I've seen two cars in which those damn things snapped- both of which left the guys stranded! (Okay so they just needed a lift to the parts store- but still!) I saw a third one snap during that 2.8-to-2.8 swap I helped my friend with- he tried to take the hose off, and it snapped- then he tried to get that part from a junkyard, found two cars- but they both snapped when he tried to get them out!

Dean, you're the man with those fittings!! Next order to Summit that I do, I'm picking up the Earls' fittings so I can eliminate that TB coolant line and run my heater hose right to the intake manifold. It sure beats my original plan to just take a hacksaw to that pipe and flare the end to make a "bump" for a hose clamp to hold onto!

 

The part number for the lower molded heater hose that comes out of the water pump for the 87'-89' 2.8 with A/C is 14101544. Its Discontinued, and no longer available from GM, so that takes care of finding a NOS part. If a straight piece of hose won't work, check out the used F-body parts sellers mentioned throughout this site. Also, Tomp is correct, the heater bypass valve was junk, and should never have been placed in the V6 cooling system. It was vacume operated, and its intended purpose was to shut off the flow of hot coolant through the heater core during AC operation, thereby keeping the passenger compartment cooler. It made no real improvement in the efficiency of the air conditioning system since the F-cars used such a big unit anyway from the factory. Usually what happened with them is: a., they leaked and caused the car to overheat, or b., they leaked and coolant was sucked into the HV/AC control panel in the dash ruining it. Glad its not on my 85'

 

Ouch; I didn't know that could happen too! Thanks for the info!

And yeah the first guy I saw that snap for, he called me to help him out- I was like "what the HELL is that"? We pulled it out and took it to Pep Boys where they knew what it was, and installed a new one. So I'm definately glad I never had one to begin with.

And back when I had A/C in the car, it always blew super-cold, so I never bought that idea of "it makes the a/c cooler". People that say that probably need their A/C system leak-tested, evacuated, and recharged.

 

That sounds good. I may just toss that whole dang valve then. Water flows -

Out of the Intake Manifold
Into Turbo
Out of Turbo
Into Heater Core
Out of Heater Core
Into Valve
Out to Water Pump

WTF - I never realized the bottom hose just recirculated!! WTF!!! Stupid, GM, just stupid.

Ok, so that Y part of the metal line is going to get capped, and the new flow shall be -

Out of Intake
Into Turbo
Out of Turbo
Into Heater Core
Out of Heater Core
Into Waterpump

The nipple on the waterpump - does it push, or pull, coolant?

 

Doward, that nipple inlet on the waterpump pulls water into it. If that return line was not there, the the pressure would build to high on the engine ports and also strain the waterpump itself because when the thermostat is closed there would be no flow at all- 100% restriction. Those recirculation lines coming out of the motor before the thermostat block (thermostat closed) are to relieve strain on the pump and always assure water movement helping to eliminate hotspots also.

The recirculating path is your main source of constant engine temp. It will just recycle through the loop uncooled by the radiator until it reaches therm temp. The therm will open to allow the water higher than the therm temp through and new cooler water from the radiator enter the loop keeping the recycle loop consistant temp at say 180*( if a 180* therm is in there). If everything ran back to the radiator then it can actually cause in colder wheather not to ever reach the 180* operating temp sometimes and not be consistant especially at different rpm speeds. Your motor would wear out faster from fluctuating operating temps.

 

LOL, Dean, you misunderstood me - I was talking about the heater diverter valve - it just recirculates the water in a loop from the heater core. That's just plain stupid!

 

I understood perfectly. The water/coolant goes from the intake to the valve FIRST- the diverter valve position determines if the water continues to the heater core or not.

What I am trying to explain is the water comes from the intake manifold to the diverter (closed) and back to the waterpump.
-or-
the water comes from the intake manifold to the diverter (open) then to the heatercore, and then back to the waterpump.

The diverter just enables a longer path to the heater core but is still the same basic recirculating constant path that maintains operating temp.

With either path being used (short or long based on diverter selection), when the water reaches the thermostat temp, the thermostat opens to let "some" of the higher temp water back to the radiator (thus allowing "some" of the cooler radiator water to enter maintaining the aprox thermostat temp range. If the temp is too low, the recirculating loop remains closed until the engine heat warms it to the thermostat operating range.

This is actually not a stupid design because it enables the motor to remain very consistent in operating temp no matter how large of a radiator is installed (the radiator could be 10times the size with ice cold water coming in but the therm will only open recirculation loop just enough to maintain the 180* operating temp (or 160*, 195* what ever therm selected for running temp.)

If the radiator is too small, then the water returning will not cool enough to reshut the therm and the recirculation loop will go above the 180* even if thats the desired operating temp. However, GM designs the cars with an appropriate size radiator to handle the length of recirculation path, combined with the motors HP(heat buildup) and the desired stock operating temp (stock therm is 195*

Now if you modify the motor, like anything, you have to modify everything else to mate the higher needs including the cooling system, the drivetrain, the brakes, the suspension. Every car out there does if the motors are altered- so every other car made would have a stupid cooling system also if you want to label it that way? You just weren't underatanding the proper recirculation path utilizing the diverter.

Water does not just circle from the heater core to the diverter and back to the heater core in its own circle. The diverter in line either allows water to flow TO the heater core or not to flow to it. remove it and hot water will ALWAYS go to the heater core (even when you are trying to get the fan to blow the A/C. This is whay the dirverter is there to block the coils from releasing ANY heat into the cockpit when not wanted making the A/C function about 5* cooler inside the car.

Take that recirculation loop out of the cooling system and you will "hotspot" and thus crack a cylinderhead from water boiling away and leaving air pockets in the cooling ports (because it is not moving behind the closed thermostat with no recirculation movement provisions.) You NEED an unobstructed path of flowing water to the pump and into the engine at all times to keep water moving (aka-recirculation loop) The water inside the engine can NOT stop flowing.

I hope this explains clearly how the entire basic cooling system works and how each section functions. Something that really is fairly basic is very commonly not understood because of all the different hoses running to different areas. The average person usually gets the direction of flow in a particular hose backwards from what direction it is really traveling.

 

To throw another curveball into the topic, it is costing me a total of about $2400 to upgrade my cooilng system to handle "completely trouble free" and very consistent at 175* in 45* weather, and in 100* weather running ***** out on a hot road course lap after lap with 250 HP (actually, it will handle 700 daily street use even when I'm done- main thing is very consistent at 175* with 250hp, no fluctuation at all ) Not at idle, nor at 8000 rpms. I like insurance that things will handle for example 50mph even though I will never go over 25mph- built in safety margin that promote reliabilty. I don't like when a car get stuck on the side of a road for any reason. Most build a car to go really fast for 3 laps, I build a car to go semi fast for 100 laps. Now in a race that is 20 laps, I am slower the first three laps, but I always finish the race, the other car doesn't.

I have preached many times on this board about "marrying componants on a car" and also that I "always biuld the car to handle the power first before I add the power" hence why me building the high HP motor is coming last. I am now working on this part of the car an marrying things properly.

 

Ahh... I see. I thought the valve kept the coolant in the heater core circulating - instead, when vacuum is applied, coolant comes into the valve, and back out - to the nipple of the water pump.

Yeah, that valve is going to be history in a few minutes.

From what I'm seeing here, the water WILL circulate without the diverter valve, as the coolant passage in the intake manifold is unaffected by the thermostat - the thermostat sits above it, in an open chamber - the water pump will pull the coolant from the intake manifold (through the turbo and heater core), regardless of whether or not the thermostat is open. The thermostat opening, will force most of the coolant through the larger path - that of out the manifold, into the radiator, and back to the water pump, to get forced through the engine once more.

I plan on picking up an aluminum radiator before much longer. I don't need it, no, but I like to know there's plenty of extra cooling capacity in the car. Although I may upgrade the fan, first!

 

So, vsixtoy, if I want to remove my heater core (it's really unecessary for me since I live in the tropics) all I need to do is run a hose from the intake to the water pump. This will allow the constant flow of coolant that is needed. Is this correct?

 

That is correct.

 

Cool! It's gone this weekend! I do have some more questions though. Since we're on the topic, I'm also gonna get rid of my heater core altogether. I was wondering if there is any other part of the heating system I can get rid of. Specifically, is there any part of the box where the core sits that I can remove without affecting my ac? Also, how will my cooling system capacity be affected? That is, how many liters less, if any, will I have to add next time I service the system? Thanks again.