I own a 1989 ford ranger. for some reason my heater takes a long time to warm up...yea warm up it never seems to get hot. also my temp gauge never seems to more much either. can anybody help with anything to check?

 

yeah sounds like the coolant is low or you have a bad t-stat. common problem, and the t stat is a cheap repair.. Kurt

 

Have seen a few with the heater core plugged up with the powdered type of radiator stop leak, but if that is the case, your heater hose to the core should still be hot.

 

i agree with the stop leak. they should ban that stuff, but if the sender says its cold and the heater blows cool, i would look at replacing the tstat. plus most people couldn't tell you when it was replaced last. it should be done every 36k or whenever you drain the cooling system.. Kurt

 

thank you i'll try those things. anybody know the t-stat is?

 

at the engine end of the upper radiator hose. unless it is a 7.3l diesel and then it is at the engine end of the lower hose.. Kurt

 

Howdy guys. I registered here because I have the same problem with my 94 Ranger 2.3L that I am using for a daily driver. I have changed the thermostat (195 deg), verified that water is flowing (filled slowly so I could see it flowing via an open radiator), verified that the radiator and overflow are both full, and I still can't figure out why on earth the heater won't get hot. The Temp gauge is on the heater hose input side, and it barely moves - even after running down the highway for 30 minutes or more.

Any other suggestions would be greatly appreciated.

 

Do your heater hoses get hot?

 

Hi Ken. We just spent an extended lunch hour looking into the problem. The heater hoses do get hot - not excessively so, but certainly noticeable. We took the thermostat out to check the water pump, and water flowed through the system just fine. Of course, as soon as you got moving at all, the water temp went from luke cold to cold as heck. LOL.

Put the thermostat back in, and now I'm blowing cold, and the heater core outlet hose is pretty cool to the touch. It appears I'm not getting water through there. Is there a coolant cut-off that you might know of somewhere inside the firewall? Mine is a 94, so I don't have anything on/in the hoses under the hood.

Many thanks.
Bob

 

Update - It's something in the heater core or that area.

I can run one heater hose in a loop, with the temp sensor as part of that loop, and the temp will get up to normal operating range in a reasonable amount of time. When I put things back to stock....ie....going through the heater core, temp gauge goes bac to way low.

I disconnected the outlet from the heater core and ran it loosely direct into the radiator (knowing the system wouldn't be pressurized). Started the truck, and no coolant came out of the core hose at idle. When the engine was run up to 2000 rpm or more, fluid started to flow - the higher the engine speed, the more the flow.

Finally, I disconnected both heater hoses at the engine side, and tried to blow blow through the hose. VERY difficult to do. I could actually run some water BACKWARDS though the core....ie.....put water into the outlet side and it would come out the inlet side....but not through the way the coolant is supposed to flow.

This leads to one of two conclusions...

1) The heater core is mostly-clogged.
2) A valve of some sort in the heater core is not operating properly.

Which leads me to my question...is there a valve in the core area under the dash? Once again, this is a 94 2.3L Ranger.

Many thanks for any info.
Bob

 

I would suspect a clogged core, the valve on my 2000 truck is in the engine compartment. Try backflushing the core with the hose.

 

if you disconnected the heater hoses fron the core, there must not be a valve under the dash, right?? a heater valve is usually somewhere in the hose from the engine to the heater core.

 

It's the core. I switched the heater hoses so that the water is going backwards through the core. It's noticeably better on the gauge, and I can get more water to go through the core. I don't believe there is any valve (I bought a Haynes manual) - I think the thing just got clogged. Heater cores are only $17 at Autozone, and it looks like a real easy swap, so that's what I'm doing.

Thanks for all the help and ideas.
Bob

 

wow, where are you at, 17 bucks is pretty cheap. I couldn't find one less than 30 out here in san diego

 

Va Beach.