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SL6 Heater question
https://slantsix.org/forum/viewtopic.php?t=32985		 Page 1 of 6
Author:  Aggressive Ted [ Thu Dec 25, 2008 6:00 pm ]
Post subject:  SL6 Heater question
Is there anyway to get more heat out of a SL6 like more my 440 cars? or is this physically impossible?

I have a newly rebuilt engine, new SL6 stock Modine radiator, new hoses, new heater core, new 195 degree Super Stat, 2 gallons of antifreeze a 16" fan on the radiator which rarely comes on and cardboard 8" up the front of the radiator.

When it gets down below freezing it takes about 5 minutes to really start to warm up. For the same time my 440 cars are baking me out with blistering heat. Is the extra heat generation from the V block design? Where as the slant is more prone to better cooling?
Author:  SlantSixDan [ Thu Dec 25, 2008 6:40 pm ]
Post subject: 
C'mon, Ted, cut us a break, willya? :lol: The answer to this question is still the same as it was the last time you asked it, in 2007. There is still nothing about the slant-6 that makes it deficient in heat production relative to V8 engines. Your water jackets are still not "too big". Your radiator is still not "too efficient". Your cardboard in front of the radiator is still a band-aid trying to address the symptom rather than the problem. There is still something the matter with your heating and/or cooling system, you just still haven't done the work to find and fix it yet.
Author:  Reed [ Thu Dec 25, 2008 6:45 pm ]
Post subject: 
Five minutes below freezing to warm up is pretty good.

Is your antifreeze 50/50 mix? Should you adjust the percentage for your climate? Is the antifreeze full? Have you hooked up the hoses to the waterpump/head backwards? Is there some kind of water shutoff valve turned on?
Author:  Eric W [ Thu Dec 25, 2008 8:24 pm ]
Post subject: 
Hmmmm, I'm kicking out warm air in only a couple of minutes (enough to clear any fog on the windshield) and am toasty in around 5 min. or so. How long do you let the car warm up before driving it? As soon as the engine kicks off the first step of the fast idle cam, the Satellite is in gear and moving which helps the engine warm up faster. Just don't romp in it while its warming up (Kinda hard to do where we work at since the freeway is only what, half mile away if that?).
Author:  Aggressive Ted [ Fri Dec 26, 2008 8:27 am ]
Post subject: 
I only let it warm up about 2 minutes and then leave. On the frozen back roads, I up to about 45 mph in about 5 minutes after leaving the drive way.

That anti-freeze mix may be a little on the strong side, 60/40.

Dan,

I bought another heater core and new lines, with no shut offs since the last time posted back in 2007 when everything was brand new. I am also running the 4th 195 degree Super Stat, and a new 16 pound cap. I also put in a new heater fan motor and rebuilt the entire heater box....no outside air is coming in at all. I recirculate the cabin air only to help it warm up faster. I guess when it is below 20 degrees it just takes a long time to warm up once under way. The only time it warms up nicely is when the temps are in the 40's. If the temps are in the 20's at freeway speeds it takes about 30 minutes.

Reed,

I don't see how you can swap the lines since they are much different diameters. :shrug:
Author:  Joshie225 [ Fri Dec 26, 2008 8:52 am ]
Post subject: 
There is no way to recirculate cabin air on an unmodified A-body. Did you block off the cowl inlet and open the passenger's side vent door or something?
Author:  Aggressive Ted [ Fri Dec 26, 2008 11:55 am ]
Post subject: 
Yes it is totally blocked, and cut the end of the heater box off so it pulls only cabin air to warm up quicker.

After about 15 minutes of driving at 35 mph the car will start to warm up.
Author:  Reed [ Fri Dec 26, 2008 12:04 pm ]
Post subject: 
Quote:
Reed,

I don't see how you can swap the lines since they are much different diameters. :shrug:
In life, anything is possible. :wink: I've done it a couple times....not on purpose of course.

Well, try blocking 3/4 of the radiator and see if that helps any.
Author:  Joshie225 [ Fri Dec 26, 2008 12:08 pm ]
Post subject: 
Any cold outside air leaking in? My '72 B300 had an air leak at the driver's side vent door and the heater couldn't keep up on the highway in low temps.
Author:  Aggressive Ted [ Fri Dec 26, 2008 12:42 pm ]
Post subject: 
I have had my passengers feel around up where the inlet is and none have felt any cold air coming in from the inlet. Around the door jam yes, a little.

I have my back seat out to be reupholstered. However, I bought a new felt pad and trunk divider which is hanging in place. I wouldn't think that would make much of a difference. Still working on installing the rear window defroster and installing new rear speakers.
Author:  Reed [ Fri Dec 26, 2008 12:43 pm ]
Post subject: 
Hmmm. How is the gasket around the fan on the firewall?
Author:  freedhardwoods [ Fri Dec 26, 2008 1:00 pm ]
Post subject: 
I don't have any suggestions, but I thought I would let you know that my /6 is slow to warm up also. I installed a new 195* thermostat in mine to try to help, but it didn't seem to make a difference. I cut a piece of plywood to block most of the air. That seems to help a little after it warms up, but it doesn't speed up the warmup time. In all the investigating I did (Heater Ductwork thread), it looks to me like the blades on the fan blower wheel are angled wrong and it doesn't put out as much air as I think it should either.
Author:  wjajr [ Fri Dec 26, 2008 1:35 pm ]
Post subject: 
Antifreeze mix should be 50/50 for best heat transfer.
Check water pump to see if it is pumping.
Check the two steel nipples where the heater hoses join the water pump and head.
Check heater hoses for ability to flow coolant.
Flush the heater core. Remember not to exceed 17 psi water pressure.
Check adjustment of all trap doors & flappers in heater box.
Check for air leaks around doors, windows, fire wall, and seal up the cave open to the trunk.

Years ago my 273 ci powered Dart would take 6 miles of interstate driving before the heat would blow hot when ambient temperature was -20 deg. F. It held over four gallons of coolant, and an abundance of cast iron. Once the engine warmed up the heater could easily heat the interior to the low 80s.

With an ambient air temp of +25 deg. F., my present Dart rag top blows hot air in just a few 'around town' miles of driving with a freshly rebuilt heater box, new heater core & hoses, fresh fire wall gaskets, and 180 deg. thermostat.
Author:  Aggressive Ted [ Fri Dec 26, 2008 3:05 pm ]
Post subject: 
wjajr,

Thanks! That's good to know. All parts, water pump, nipples, hoses etc. are brand new. Firewall is good, but the passenger door sides leak a little at 70 mph. All gaskets are in good condition.

My V8-440 cars are fine, just the sixes are colder. That includes on truck, a van and the 74 Swinger.
Author:  Eric W [ Fri Dec 26, 2008 3:07 pm ]
Post subject: 
Maybe try a 13 lb cap, lower the boiling point.
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