Thumping noise from dash!
#1
Thumping noise from dash!
Ok I have a 1998 Ford Ranger XLT 4.0L automatic 4X4 with A/C my problem is i just had the timing chain,water pump, thermostat, upper and lower hoses, and front crank seal replaced. I got it back and right away noticed a thumping noise at idle only... My gauge was always steady at the same spot it had always been. but the thumping was loud when idleing. Now the sound seems to have moved farther towards the engine insted of the dash and tonight when i popped the hood noticed the top hose was collapsed and i could feel no pressure. the thumping noise seems to be comming from the area of the thermostat. I have no oil in the coolant and no coolant in my oil! I tried to get the air bubble or pocket out if thats what is the problem by rubnning the engine till hot with the radiator cap off but it made just a huge mess. it did seem to push a huge air pocket out but still does the loud thumping. This all started the day i got it back from the mechanic so im assuming its an air pocket. please let me know if anyone can help ... I planned on changing the thermostat tomorrow. Thanks in advance... Dave
#2
Have you talked to the mechanic about it?
I would pull the T-stat and make sure it was installed in the right direction (spring-side facing the engine).
Something else to keep in mind:
I would pull the T-stat and make sure it was installed in the right direction (spring-side facing the engine).
Something else to keep in mind:
ARTICLE NO. 99-23-8
• GAUGE—TEMPERATURE GAUGE FLUCTUATION AND/OR “KNOCKING/THUMPING” NOISE FROM COOLING SYSTEM—4.0L OHV ENGINE
• COOLING SYSTEM—PULSATING COOLANT FLOW —NOISE—“ KNOCKING/THUMPING”— AUDIBLE IN PASSENGER COMPARTMENT—4.0LOHV ENGINE
FORD: 1995-2000 EXPLORER, RANGER
This TSB article is being republished in its entirety to include 2000 model year vehicles and to provide Service Part(s) and Labor Time information.
ISSUE
A temperature gauge fluctuation and/or a“knocking/thumping” noise may be audible in the passenger compartment on some vehicles. This noise is most pronounced with the engine at normal operating temperature. The noise is caused by steam formation in the cooling system. The noise is then transmitted through the heater hoses and heater core.
ACTION
Install a Coolant By-Pass Kit. This increases coolant flow which reduces steam formation. Refer to the following Diagnostic and Service Procedure for details.
DIAGNOSTIC AND SERVICE PROCEDURE
1. Check for excessive exhaust system restrictions. A restricted exhaust could elevate cooling system temperatures.
2. If dash-mounted cooling temperature gauge fluctuates, check that gauge and sending unit are functioning properly.
3. Check for restrictions or kinks in the radiator or heater hoses.
4. Pressure check cooling system for leaks.
5. Confirm proper Engine Coolant Temperature (ECT) sensor signal to EEC-V processor.
6. Check for correct 50/50 coolant mix. Verify that freezing point is -37*C (±-15*C) or -35*F (±5*F).
7. If concern still exists, install service Coolant by-Pass Kit and verify that concern has been resolved. Refer to the Application Chart in this article.
PART NUMBER / PART NAME
F8PZ-8522-AA / Coolant By-Pass Kit (‘95-‘96 Ranger)
F8PZ-8522-CA / Coolant By-Pass Kit (‘97+ Ranger)
• GAUGE—TEMPERATURE GAUGE FLUCTUATION AND/OR “KNOCKING/THUMPING” NOISE FROM COOLING SYSTEM—4.0L OHV ENGINE
• COOLING SYSTEM—PULSATING COOLANT FLOW —NOISE—“ KNOCKING/THUMPING”— AUDIBLE IN PASSENGER COMPARTMENT—4.0LOHV ENGINE
FORD: 1995-2000 EXPLORER, RANGER
This TSB article is being republished in its entirety to include 2000 model year vehicles and to provide Service Part(s) and Labor Time information.
ISSUE
A temperature gauge fluctuation and/or a“knocking/thumping” noise may be audible in the passenger compartment on some vehicles. This noise is most pronounced with the engine at normal operating temperature. The noise is caused by steam formation in the cooling system. The noise is then transmitted through the heater hoses and heater core.
ACTION
Install a Coolant By-Pass Kit. This increases coolant flow which reduces steam formation. Refer to the following Diagnostic and Service Procedure for details.
DIAGNOSTIC AND SERVICE PROCEDURE
1. Check for excessive exhaust system restrictions. A restricted exhaust could elevate cooling system temperatures.
2. If dash-mounted cooling temperature gauge fluctuates, check that gauge and sending unit are functioning properly.
3. Check for restrictions or kinks in the radiator or heater hoses.
4. Pressure check cooling system for leaks.
5. Confirm proper Engine Coolant Temperature (ECT) sensor signal to EEC-V processor.
6. Check for correct 50/50 coolant mix. Verify that freezing point is -37*C (±-15*C) or -35*F (±5*F).
7. If concern still exists, install service Coolant by-Pass Kit and verify that concern has been resolved. Refer to the Application Chart in this article.
PART NUMBER / PART NAME
F8PZ-8522-AA / Coolant By-Pass Kit (‘95-‘96 Ranger)
F8PZ-8522-CA / Coolant By-Pass Kit (‘97+ Ranger)
#3
Yea thats it I get a loud thumping noise bad after it reaches normal operating temp! I will try a oem thermostat sunday on my day off... My question also is how come the upper hose collapses? its like flat...Yes I did talk to the mechanic and what he was saying was to change the thermostat also. If that didnt do the trick he was going to do a chemical test to see if its the head gaskets. I really dont think for a second its the headgaskets. It started exactly after he did the work, hense air bubbles or pocket is what i was thinking. But thats why im here to get some expert opinions. Thank you.
#4
#5
I'm still thinking that there could be some sort of obstruction in the cooling system. That would include such possibilities as a clogged radiator, and even a bad water pump.
Why did you have the timing chain, water pump, thermostat, upper and lower hoses, and front crank seal replaced in the first place?
Why did you have the timing chain, water pump, thermostat, upper and lower hoses, and front crank seal replaced in the first place?
#6
I had the timing chain done due to a coolant leak from the timing chain cover! After the timing cover was removed i discovered a very worn timing chain and gear worn also so decided to replace all of it including the front seal. I figured since i was doing that i would replace the upper and lower hoses and waterpump while i was there. One thing i did do yesterday is while idleing and it was making the thumping noise, I shut the heater off! The noise went away until i turned the heater back on then after 1 to 2 minutes the noise comes back. Also I have recently noticed that I smell a strong oder of coolant when I first start the truck inside of the cab! Oddly enough The noise stays away as long as i have the heater off!
#7
Sounds like a leaking heater core. Probably get an oily film on your windows too right? It explains the persistent coolant issues. O yeah, could just be the heater hoses too, but good idea to change the core with the list you mentioned anyway.
Last edited by matt's2.9STX; 12-20-2009 at 08:23 AM. Reason: Forgot stuff
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#9
Make sure & check the hoses b4 you go to all the trouble (probably fairly easy & CHEAP) of pulling the core to whether it really is the core or hoses. I'm not sure if it's easy or not on a '98. Seem to remember a lot of changes to access from 80's & early 90's setups. On our 94's, the core itself should be R&R in 1/2 hour. You will have to go through burping system again to get that air pocket out.
#10
#11
Update!!! I cant find a leak anywhere at all :-( I looked at the heater core and hoses not a single leak and even hooked up a pressure tester and it passed. The coolant level has stayed the same to! Hasent used a drop... Anyone wanna help me figure what this could be? maybe i still have a airpocket in the heater core area???
#12
I agree that it still sounds like an obstruction somewhere, and the collapsed top hose really points to the thermostat (yes, even though you replaced it already). If it's not a huge job, I'd be tempted to pull the thermostat again and check that it's good, maybe even reassemble with no thermostat to see if the problem persists. Have to ask a dumb question, sorry - you sure you put the thermostat in the right way?
#13
I agree that it still sounds like an obstruction somewhere, and the collapsed top hose really points to the thermostat (yes, even though you replaced it already). If it's not a huge job, I'd be tempted to pull the thermostat again and check that it's good, maybe even reassemble with no thermostat to see if the problem persists. Have to ask a dumb question, sorry - you sure you put the thermostat in the right way?
#14
Yes I did put the thermostat in the right way and its not a dumb question ty for helping me. It works and keeps working as long as i dont turn the heater on i could go all day without the heater on and then turn it on and it starts within a couple minutes but only at idle. I have to leaks anywhere and have not lost a drop of coolant.
#15
I'm not real familar with that truck - is there a valve in one of the heater hoses that is controlled by the heater setting? Seems there would have to be for the heater on/off to affect the noise. And if there is, being closed or open is likely to have an affect on the water flow in the pump/thermostat area... I can't make sense of that and the collapsed top hose together though... The lower hose usually has a spring coiled inside it to keep it from collapsing, but there should be no vacuum at the top hose unless there is a blockage where that hose meets the engine - which again points to thermostat... Hmmm...