97 5.0 overheat engine & no heat

[monty98]

On trip 2 hrs from home check gauge light came on & temp gauge red lined! Pulled over. Checked to see if hose or coolant issue. Coolant level as when checked night before. Deciding which vehicle to take on the trip 98 or 97 the 98 wasn't producing heat (need replace the control that goes on the box behind glove compartment. Heat was hot & ran consistent on the 97..so that became selected vehicle. Little apprehension as hadn't driven it except home after mechanic changed passenger exhaust manifold, head gasket, new fuel injectors & plugs. It was running great til the overheat issue. What I had noticed morning was a slight very quiet whistle near front engine only hear with hood up...couldn't see any issues. Also noticed gurgling sound seemed like center possibly firewall area. The gurgling not always evident but noticed on load or acceleration it got louder but only occasionally. Thought it might just be air in the system after all hoses off etc for the work done. But then the redline without any notice. Wasn't running heat at time so after cooled down thought maybe drive with heat on which would help if thermostat issue. But no heat. Hoses hot tho. Limped along stopping time to time til could get off freeway. It would cool when basically coasting downhill but as soon as had to accelerate to go uphill the gauge would start climbing. I was in very hilly area so no options & had to get off freeway! Went back next day & hauled it home on trailer.

Love this type issue just when going into cold weather & no place inside to work on it. Had done a flush about year before & had a small leak & some coolant in exhaust. Used K-seal & it helped some before all the mechanical work described above due to #3&4 serious misfires even after new plugs, wires.


Does what I describe about the overheat/no heat issue sound like the pump gone bad? Its got about 136k on it & read often around 150 might have issues (wish had known when everything else was apart). One mechanic without seeing it, based on description says pump (2 mechanics work on this vehicle regularly). Anything else I should check...any possibility something else? Oh the tstat was changed year ago but with no heat & overheating engine doesn't seem likely culprit. But whatever it was went fatal without much notice.

Sorry so long but thought might be helpful to know what has been done so far. I've searched forum but nothing quite like this shows up. Thanks in advance for any input.

 

[Turdle]

Are you checking level of coolant in reservoir or in the radiator?

The reservoir works in a manner which will allow a chunk of debris inside it to block flow into radiator. when and if coolant in rad goes away it cannot be replaced because of the clog, reservoir remains full. You mentioned k seal, which would compound this issue. Radiator pressure will push the clog out of the way to allow coolant into the overflow, clog settles down and blocks flow back to rad.

Since thermostats are cheap, I'd replace it. Squeeze lower hose, does it collapse easily? This would block coolant flow.

 

[1998Exp]

On trip 2 hrs from home check gauge light came on & temp gauge red lined! Pulled over. Checked to see if hose or coolant issue. Coolant level as when checked night before. Deciding which vehicle to take on the trip 98 or 97 the 98 wasn't producing heat (need replace the control that goes on the box behind glove compartment. Heat was hot & ran consistent on the 97..so that became selected vehicle. Little apprehension as hadn't driven it except home after mechanic changed passenger exhaust manifold, head gasket, new fuel injectors & plugs. It was running great til the overheat issue. What I had noticed morning was a slight very quiet whistle near front engine only hear with hood up...couldn't see any issues. Also noticed gurgling sound seemed like center possibly firewall area. The gurgling not always evident but noticed on load or acceleration it got louder but only occasionally. Thought it might just be air in the system after all hoses off etc for the work done. But then the redline without any notice. Wasn't running heat at time so after cooled down thought maybe drive with heat on which would help if thermostat issue. But no heat. Hoses hot tho. Limped along stopping time to time til could get off freeway. It would cool when basically coasting downhill but as soon as had to accelerate to go uphill the gauge would start climbing. I was in very hilly area so no options & had to get off freeway! Went back next day & hauled it home on trailer.

Love this type issue just when going into cold weather & no place inside to work on it. Had done a flush about year before & had a small leak & some coolant in exhaust. Used K-seal & it helped some before all the mechanical work described above due to #3&4 serious misfires even after new plugs, wires.


Does what I describe about the overheat/no heat issue sound like the pump gone bad? Its got about 136k on it & read often around 150 might have issues (wish had known when everything else was apart). One mechanic without seeing it, based on description says pump (2 mechanics work on this vehicle regularly). Anything else I should check...any possibility something else? Oh the tstat was changed year ago but with no heat & overheating engine doesn't seem likely culprit. But whatever it was went fatal without much notice.

Sorry so long but thought might be helpful to know what has been done so far. I've searched forum but nothing quite like this shows up. Thanks in advance for any input.

The two issues may be unrelated. If both heater hoses are hot, the lack of heat is probably the infamous blend door issue. What led to the head replacement? I would check for exhaust gas in the coolant, to rule out a crack. That would heat things up in a hurry. There is a simple sniffer to check for that.

 

[monty98]

Thanks. Hoping its simply debris. There was some in the overflow before topped it off. Vehicle hasn't been started for over 24 hrs, just released pressure radiator to remove cap & it was highly pressurized & release pushed coolant back into overflow. I have put in over 1/2 gallon so far & its still thirsty. I should have checked the radiator level before the trip...assumed it was topped off by mechanic & just needed more in the overflow. I will start with a thorough flush & tstat.

It does concern me about possible crack. Head gasket was replaced due to significant misfires 3&4 & inclusive compression values, valves looked good. Where did the coolant go that allowed me 5+ hrs driving before issue? I will also check exhaust again which didn't do after getting it home from mechanic but wasn't smelling any. All my ancient vehicles have had some issues but the kseal resolved that in my pu & significantly helped in this one.

Wish it was as simple as the blend door but no its not the blend door as I have to manually turn that already (short every time hook the controller up). No matter which way turned no heat would come out at that time but worked perfectly prior.

Hopefully the overheat didn't do any damage. But this 97 has been a headache from the start so?

Thanks for all the input...I will be pursuing things mentioned.

 

[monty98]

Turdle you were right... the K-seal had settled & blocked things in the expansion tank & coolant almost gone from the system. Irritated at myself as had extra coolant with me if had actually checked the radiator...could have saved me lot of time but at least not a tow bill. Sucked all the coolant & k-seal out of there with a turkey baster & washed it clean so hose flowing freely. Even flushed heater core just in case (there have been & continue no signs of leakage there) & filled so would have less to burp. Got everything circulating freely (the thermostat is locked open) & heat. However still gurgling periodically mainly on load. Seems worse when turn heat off. With only 5lb pressure discovered a crack bottom of the heater control valve leaking coolant. That has been replaced but still have gurgling after several burpings but not from heater core area its more center now. I noticed something & need an engine anatomy lesson.

I've always just replaced hoses where they originally came from. Mechanic that did the head work evidently swapped those hoses back engine area. I know the heater core doesn't care which way it flows. However, what about the hose connections on the back side of the engine? Is there anything about those two connections that is directional considering one has the heater control valve on it?

Hoping just need to tighten the hose connectors down there. The gurgling is puzzling considering can't find leaks or drips but if small leak it would burn off like it was doing with the cracked heater control valve so was slowly loosing coolant. With thermo stuck open (will replace after figure this gurgling out) & parking vehicle with substantial rise so radiator higher than heater core area shouldn't it have burped adequately after 4 plus times? Are there other things I should be looking at?

Thanks all for your input. This forum invaluable as have found answers to so many questions over the years.