Did you change the tensioner?

The idea I am suggesting is that the tensioner might not have been adjusted when replaced during the last belt change, thus been a bit too slack and allowing the pump to slip as shown by the marks on the belt. It would slip when more "work" was required of the pump due to the higher RPM. At last that is an hypothesis I am making here.

Reference links:
http://www.the75andztclub.co.uk/forum/showpost.php?p=1889531&postcount=24

http://forums.mg-rover.org/showthread.php?p=2934932#post2934932


I am also attaching the reference procedure for the tensioner from INA (the oem manufacturer of the tensioner supposedly) itself.


Was the tensioner changed? and was it adjusted as described in those forum thread and this pdf?
 

Attachments

  • KV6 TB tensioner pulley adjustment procedure (1).pdf
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I checked the belt tension before remove and seems to be good. Today I went to buy the water pump, but is holiday in another state that imports the part; Only on Monday now.
 
comdek said:
I checked the belt tension before remove and seems to be good. Today I went to buy the water pump, but is holiday in another state that imports the part; Only on Monday now.
Click to expand...

Hi comdek.

Was the tensioner already tighten properly according to the info I pointed out? Supposedly some tensioner come from factory properly and some do not.
 
I didn´t changed the tensioner, but my mechanic when changed the timmingbelt, was removed the pulley from support.

I checked the belt tension was good before removing this time.

Here is my tensioner config now:
71.png
 

Attachments

  • tensioner1.jpg
    tensioner1.jpg
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Last edited:
comdek said:
I didn´t changed the tensioner, but my mechanic when changed the timmingbelt, was removed the pulley from support.

I checked the belt tension was good before removing this time.

Here is my tensioner config now:
View attachment 93161
Click to expand...
The angle seems good thanks for the picture. The other thing to make sure is to tighten the Allen key bolt on the tensioner. Some report of that bolt being only finger tight (as in able to untighten with only fingers and not using any wrench or Allen key)

Many people have commented to replace tensioner and he idler pulley when replacing the belts. If the bearings in either of these items seizes, the belt will shred and then many valves win the engine will need replacement. As you might know the KV6 is an interference engine.

I would be concerned about the life of the bearings in the tensioner and the idler pulley.
 
Today I bought a new water pump and installed on KV6. After I pressurized the system with 12PSI and put detergent bubbles outside the pump to check for any leaks. The sealing is ok.
Installed the timing belt with pulleys in the marks and released the pin lock placed on the hydraulic tensioner and flywheel. Turned the engine 2 times and markings coincided.
Loaded the coolant and made bleeding as always.
The battery was discharged and no alternator installed to charge it. So I put my other car side and the parallel cable in batteries left on.

Accelerated several times and the car remained at 99 ~ 100 ° C. One thing I found strange, if sensor 2 connected (bottom hose), the temperature reached to 105 ° C with the bottom hose very hot and the fan did not run. I will leave this sensor disconnected because then the fan starts in 99°C and max speed at 108ºC. The radiador is ok, all of then is hot.

Tomorrow I´ll finish the assembly and make some ride to test if the problem is solved.



80.png
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83.png
84.png
 
The seal from oil stick tube is in bad condition, if put that way the oil will be dripping in the garage.
Tomorrow buy a new seal.
85.png
 
All parts assembled in place. :)

In garage tests, the temp reimaned in 99ºC ~ 101ºC on idle for long time and 96°C ~ 99°C varying RPM.

Tomorrow we will see if it works. I´ll go with OBD scanner connected to monitoring the temperature.
 
No luck, after engine warmed, in a climb when I used 30% of engine load, it overheated (120ºC). I don´t know what to do.
In idle after overheated, temp stays at 108ºC.

8dd49079-d1d3-4c5a-b9e5-94a89c14bf5d.jpg
 
How does it run without the thermostat in?
If it *stays* overheating there's something suspicious going on. Are the cooling fans coming on and off as expected?

This thread has been going a while, I can't remember if you've had a coolant sniff test done?
 
I make the sniff test and no leaking detected at 12PSI pressure in coolant system.

I already bought a new thermostatic valve and changed it. There's no way to leave without it is a entire part with multiple connections.
 
Hose routing? Double check everything goes where its supposed to?

Does all of the radiator get hot?
 
The hoses are connected properly and tested by inserting water to see if it was not obstructed.

The radiator is ok too, the top hose is hot but bottom hose is cold. The problem it's like a failure thermostatic valve or flow problem, but has been replaced and tested in the pan with hot water.

It can be an obstruction inside of the block, but I never see this.
 
Are you sure that the gearbox is ok. A slipping clutch could be heating the fluid more than it should. This extra heat then goes into the coolant. Just a thought.
If you still have the old thermostat. You can remove the valve by carefully breaking it. Then fit the "open" stat to see what effect it has on temperature.
 
I had this idea to remove the valve from housing, but if have a obstruction in some cylinder head for example, it will destroy the engine when at full load.

I'm wondering if I will fix this engine or make a swap for a diesel engine with manual transmission. I'm also problem in Jatco box too, which most often does not come from 3rd to 4th gear.
 
Comdek I admire your persistence and resilience, lesser men would have given up long before now.

As a check; new pump, new thermostat not sure of what else you have changed? Given that all of the usual suspects have been checked and changed, it now remains to eliminate the impossible so that whatever remains, no matter how improbable must be the cause. What I am suggesting is, draw a list up of everything that can cause the car to over heat, check it methodically and when it is confirmed it is OK move on to the next one in the list.

Keep going and best of luck.
 
I think the problem is the HGF. I opened the reservoir now the night and saw a small smoke with exhaust smell.
B34R said about the sniff test, but I got it wrong because of translation into Portuguese. :D

I will buy a transparent hose and will change the output of the intake manifold. So I´ll see which cylinder head is leaking compression gas. If confirmed, this weekend I´ll remove both cylinder heads to change de head gaskets.
 
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