Bought a 97 RAM 1500, 180K. Engine runs good and seems to run up to temp. Heater hoses seem warm (hot) enough to me

But the heater output seems less than optimum, and it's not even cold yet. Worse, I "rung it out" on a trip to see a friend about 120 mi round trip, hilly. When going up a hill, even "little" the vacuum drops enough that the vacuum doors shut down.

Ideas?

I have an online copy of the shop manual, but frankly, navigating them is tough

I have printed copy of a Dakota manual I got cheap. Would they be close?

SECOND question

Where do I find out what all the titles are to the "full set" of shop manuals? How many are there (printed?)

 

"Full set of shop manuals" is a total of two books. You already have one, then there is the 'diagnosis manual', which I begin to wonder if it even exists.... as I have NEVER seen one.... only heard rumors of it.

You more than likely have air trapped in the heater core. Simply burping the cooling system doesn't seem to be adequate to the task... need to pull the hoses, backflush the core, and then make SURE it is full before reattaching the hoses.

Take a look at the 'wild vents' thread in the FAQ section for the fix for your vents switching.

 

Along with the vacuum issue, I suspect the thermostat has failed with the top hose is just warm.

 

Speaking of thermostats, if it has a 180° thermostat, it wont produce and abundance of heat in the cab, even if all else is fine.

If heat hasn't been used for a long time, the decaying foam on the blend door may have stuck it in the a/c position, so no heated air enters the vents... mine was like this (hadn't used heat for 3yrs)... took a week of randomly cycling the switch back and forth to break it free (probably 40 cycles total)... then a heap of foam crumbs came out the vents, along with warm air.

 

It seems to blow "plenty" of air. The problem is twofold

Not enough heat, which might indicate a door problem, even though the hoses seem plenty warm to me. I'll get some thermometers on them

And it goes away when going up hills

I just ordered some manuals off ebay

Not sure you are correct about "just two manuals." I found a listing which claims to be the anti skid diagnostics manual, as well as air bag diagnostics. This kind of stuff popping up is why I'm trying to find out "just what." You would think that SOMEWHERE (Mopar?) there would be an actual listing. My Ford Ranger is the same way.

I'm 67, so "crawling around" is quite painful, anymore

Thanks for the suggestions, when I get the "new" manuals LOL I'll dig into them.

 

Hey You is the diagnosis manual lol

 

check for a melted vaccum line I had one by cylinder 8 going into the fire wall replaced the line and check valve very simple and cost $6. Would be an easy start.

 

Thanks. I think......

 

Well I received a load of manuals from ebay, some of which were for the RAM VAN but I knew that. I got the diagnostics manual, the antiskid diagnostics manual, the seat belt / air bag manual and a couple of others for the VAN

The main "truck" manual was on another sale, and I'm still waiting for it. Just in time for rainy cold weather LOL

 

Afternoon all!! Similar heating problem

97 ram 1500, AC blows really cold, fan blows strong, when I switch the dial from cold to hot I hear the ‘knock’ from the door closing both ways, both pipes running to the heater core are HOT! The inlet is too hot to hold and the outlet just slightly cooler.

Motor never overheats, sits dead centre on the gauge..
when the motor is upto temp and I have the heater dial all the way hot it’s max 45°!

could this still be a heater core problem even though both pipes are hot?
Forgive me is this is wrong but I thought any problem with the heater core would cause the outlet pipe to be considerably colder than the inlet?

cheers