bob tarin

Hi,

I couldn't find a cherokee forum so I'm using this hoping to get some advice.

After a drive on the freeway when I got off I noticed my car was running rough. Looked at the guages and the temp guage was pegged. Looked under the hood and the Heater Control Value was emitting whitish smoke and was a little wet, seemed to be leaking.

When I got it home, (start engine, drive and coast, repeat about 5 times), I let it cool off. I disconnected the top water hose going into the
radiator. Started the car, let it go to 230, and no water came out.
Removed thermostat and reassembled. No water is being pumped out of
the engine.

My question. Can a defective HCV affect the output of the waterpump?
Is my water pump definitely bad since it doens't pump water. Can it go bad without leaking water on the ground ? Overflow resovoir is full and doesn't get drawn in when the engine is started and reaches operating temp. Radiator was replaced about a year ago and system was flushed.
I wouldn't think it would be a blockage on the return side.

Is my waterpump dead ?

thanks for any help. Bad time for a major repair.

jimlask

You're waterpump i think is powered by your Belts. so if it was broken, i dont know how that would work, it would have to be a broken shaft inside the pump. That whole set-up is pretty Solid though.

Does it spin Freely when your belts are running ?

bob tarin

yes, spins freely, belts are fine. I was wondering if the HCV is blocked
can that affect the waterpump output ?

ol"blue

No.

ol"blue

The water pump can be bad without leaking out of the weep hole. Rarely impeller damage has occurred limiting/preventing the pump from operating as intended.
After getting it that hot, check the oil for a milk shake look to the oil, as head gasket damage/cylinder head cracking can occur when the engine has been overheated. JMO
And Welcome to CF

bob tarin

thx for the reply ol' blue.

so it looks like it has to be the pump.

so it can go bad without any external leaking ?

any other things to check for ?

ol"blue

Yeah, we posted simultaneously. See my above post.

ol"blue

If damage is suspected, you should do a coolant system pressure test, and check the compression. You're "probably" good though. JMO

bob tarin

oil looks clear
it's just weird that it just stopped working
105,000 miles
it makes me wonder how the heater control valve starts
putting out whitish steam as soon as the engine starts warming
up because it seems to get it's feed from the 1" hose coming out
of the thermostat housing. I guess it is getting hot water from
the system being pressurized even though it isn't being pumped ?

bob tarin

unless there is a small head gasket leaking right in that area making it
appear that it's the HCV. Will a faulty head gasket allow steam to come
out ? thanks again I think I'll change the HCV just for general principle because there looks to be a small vertical crack in the black ring on the bottom area.

ol"blue

If the heater control valve is/was steaming then it's either got a loose/bad clamp or it's developing a crack in the plastic. That allowed coolant to escape and let the engine temp. rise further.

bob tarin

I changed this part about 3 years ago and it seems that they are notoriously defective. Even factory ones don't seem to last. Off to
NAPA to buy one, it'll have to be changed regardless of the waterpump.

thanks again
have a good evening

ol"blue

You too. Keep us posted.

bob tarin

duh, there was not enough water in the radiator for the waterpump to
pump ! Embarassing but I forge on. I must have lost most of my water on the freeway drive but not sure why it didn't suck it out of the overflow resevoir. That's what thru me off.

Anyway, I filled up the radiator and it came out of the top house when I started engine. HCV is still leaking so I went to Napa and they gave me a 4way HCV but it doesn't have
a vacuum port on the side like the one that's installed does. It just has a vacuum port in the middle of the dashpot on top. The one installed has the same needle type vacuum attachment on top but also has the vacuum line connected to the side. New valve doesnt' have this vacuum fitting. Was wondering if I connect the vacuum line to the top needle valve vacuum port on the new part, or if it is just the wrong part. Napa said it is the correct on from 91 to 96. When I hook up a spare vacuum hose to the only port on the new piece and suck it moves the butterfly valve inside.

Can this be a replacement or should I try to find one with the port on the side bottom as well as the top needle like port in the middle of the dashpt.

Hope this makes sense

thanks

ol"blue

I'm not sure on that.