Sounds of Draining

[Klaatu55]

Hi All, Three quick questions. On my 1999 4.0 After shutting off motor. I hear sound of liquid draining inside engine. Sounds like oil draining back into oil pan. It's loud enough to be noticeable.

Also I recently flushed and cleaned (vinegar twice and Prestone cleaner last) cooling system.Dropped lower radiator hose to drain. Flushed clear.Back flushed heater. Oil pressure 30 (by cabin gauge) at idle.No real problems just never heard this sound before in 14 years. Actron 9180 reads 203 after 30 minutes idle. Outside temperature 28 degrees. New Radiator,water pump,thermostat,thermostat housing,and serpentine belt.My flush tee is on the top hose runs from thermostat housing to heater this hose gets very hot (to hot to hold), bottom heater hose is just warm, cabin warms up. but very slow.
My questions are.
1. Is the tee on the right hose right one to back flush.Which direction does the coolant flow.
2. Should all hoses be same temperature if heater is full on.
3.What is that dripping sound.(oil going back to the oil pan??)or a better question is, is it normal.

Thanks

[Brasscatz]

Hi All, Three quick questions. On my 1999 4.0 After shutting off motor. I hear sound of liquid draining inside engine. Sounds like oil draining back into oil pan. It's loud enough to be noticeable.

Also I recently flushed and cleaned (vinegar twice and Prestone cleaner last) cooling system.Dropped lower radiator hose to drain. Flushed clear.Back flushed heater. Oil pressure 30 (by cabin gauge) at idle.No real problems just never heard this sound before in 14 years. Actron 9180 reads 203 after 30 minutes idle. Outside temperature 28 degrees. New Radiator,water pump,thermostat,thermostat housing,and serpentine belt.My flush tee is on the top hose runs from thermostat housing to heater this hose gets very hot (to hot to hold), bottom heater hose is just warm, cabin warms up. but very slow.
My questions are.
1. Is the tee on the right hose right one to back flush.Which direction does the coolant flow.
2. Should all hoses be same temperature if heater is full on.
3.What is that dripping sound.(oil going back to the oil pan??)or a better question is, is it normal.

Thanks

Yes, the tee is on the correct hose. I would figure that both heater hoses would be the same temp, although I've never really thought about it to check it out on mine. I suppose it's possible that you may have some blockage in your heater core. Is your heater running hot enough to run you out of the Jeep?
As for the draining sound, I think it's coolant. Mine does the same thing from time to time. You may have some air in your system.

[Klaatu55]

Top heater hose is too hot to touch. The cabin heat comes up to 72 but very slow. Never hot. It gets comfortable but never really hot hot.
Question where would the coolant be falling to. (unless like you say there are air pockets.) On my radiator I really cannot see the coolant flowing pass the radiator cap opening. I left the cap open to wait for the air to come out (burp) what I noticed is the fluid level rising to overflow. I normally put the cap back on to keep it from overflowing. Do you think that the air bubbles are trying to get out and I"m possibly trapping it by putting the cap back on?

[Brasscatz]

The radiator cap should let air escape I believe, kind of like a "self-burp" if you will. However, if your heater isn't getting HOT, then I would say that you have either some blockage in the heater core or you have some air in the system. I usually let it run and squeeze the upper radiator hose to burp the system, but I end up losing coolant that way. You can try getting one of these funnels http://revlimiter.net/blog/2011/03/tool-review-spill-free-funnel/
It will help you burp the system without losing coolant. Don't forget to turn your heater on FULL BLAST while doing this. Also, here's a video that will help demonstrate this.
Burping The Cooling System - YouTube

[4.3LXJ]

On the open type system of the 99, it will take care of its own burping. Burping is only a problem on the Renix era closed systems. The inlet heater hose will be hotter since the heater core removes heat from the coolant to warm the air. But if the heater is not getting real hot, there are a couple of things. One, the core may be partially blocked, or it may have junk in it blocking the flow of air. Mouse nests and old leaves are common

[Mudderoy]

I hear this draining sound too. It's so loud that when I first heard it I looked under the Jeep!

[Klaatu55]

I'll check and reflush heater core as soon as the snow goes away. Maybe pour a bottle of Prestone cleaner in to sit for a few ,and hold heater hoses up high

[Klaatu55]

After several core flushes,with higher pressure more stuff did come out of core. Heat is now up to 100 degree + cabin heat now. Also draining dripping sound is gone. I guess it was some how related.