Aaaaaaaaaaaaggggggggh O Rings!

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JamesBB

Well-Known Member
Posts
789
Location
Sandwich. Kent.
I have spent some of this afternoon attempting to get to my heater blend servos as I have no heat at all.

Followed the instructions here:
Blend Motor Diagnosis and Replacement
All was going well up to " It will require quite some flexing of the duct to get it out of the way - but it can take it the flexing."
There is no warning that you can put maybe a little too much pressure against the water pipes and then cause a coolant leak!! This seems to now be what I have. :mad:
I still cannot access the lower blend motor. Mega frustrating.

I see an O ring "how to" on here, I better order 2 and follow that before I do anymore, including re-assembly as that would be a total waste of time at the moment.

Frustrated :(
 
I have spent some of this afternoon attempting to get to my heater blend servos as I have no heat at all.

Followed the instructions here:
Blend Motor Diagnosis and Replacement
All was going well up to " It will require quite some flexing of the duct to get it out of the way - but it can take it the flexing."
There is no warning that you can put maybe a little too much pressure against the water pipes and then cause a coolant leak!! This seems to now be what I have. :mad:
I still cannot access the lower blend motor. Mega frustrating.

I see an O ring "how to" on here, I better order 2 and follow that before I do anymore, including re-assembly as that would be a total waste of time at the moment.

Frustrated :(


In my guide I use a very long screwdriver but if you cut the "hole not needed" (see photos in how to) it can be done with a shorter one and handy if screw is stuck/rounded/need extractor etc.


Your old O-rings are probably gone, so moving pipes = leak
 
O rings on the way.

I just thought, what effect would a faulty heater core temperature sensor have on the heating?

Both pipes are hot when then engine is running, so I know there is heat there and the core is not blocked. I cannot see what the HEVAC would do if the sensor failed, could it close the temp flaps and keep them both closed?

If so, the fault may not be with the blend motor(s) especially as LH and RH have failed in the same setting - closed or cold. Which would mean my main intention was pointless.

Just a thought. Can anybody offer more advice?

Thanks in advance......
 
O rings on the way.

I just thought, what effect would a faulty heater core temperature sensor have on the heating?

Both pipes are hot when then engine is running, so I know there is heat there and the core is not blocked. I cannot see what the HEVAC would do if the sensor failed, could it close the temp flaps and keep them both closed?

If so, the fault may not be with the blend motor(s) especially as LH and RH have failed in the same setting - closed or cold. Which would mean my main intention was pointless.

Just a thought. Can anybody offer more advice?

Thanks in advance......
Depends on the failure mod I would guess.
 
O rings on the way.

I just thought, what effect would a faulty heater core temperature sensor have on the heating?

Both pipes are hot when then engine is running, so I know there is heat there and the core is not blocked. I cannot see what the HEVAC would do if the sensor failed, could it close the temp flaps and keep them both closed?

If so, the fault may not be with the blend motor(s) especially as LH and RH have failed in the same setting - closed or cold. Which would mean my main intention was pointless.

Just a thought. Can anybody offer more advice?

Thanks in advance......

Also check for loose/bad connection at plug to blend motors and sensor,

if sensor fail means unit see it as hot-hot it may close flaps as effect.
If you get it on diagnostic you will be much wiser.
 
O rings on the way.

I just thought, what effect would a faulty heater core temperature sensor have on the heating?

Both pipes are hot when then engine is running, so I know there is heat there and the core is not blocked. I cannot see what the HEVAC would do if the sensor failed, could it close the temp flaps and keep them both closed?

If so, the fault may not be with the blend motor(s) especially as LH and RH have failed in the same setting - closed or cold. Which would mean my main intention was pointless.

Just a thought. Can anybody offer more advice?

Thanks in advance......

The heater core sensor is more to do with aircon than heating. The other temp sensor clipped to the pipe is to do with heating, i think it controls fan speed in the demist program setting. As the sensor detects heat the fan speed increases.
 
It's funny you should say that I was fiddling about under the bonnet was checking how stable the heater matrix pipes were.
They are not very stable !
And low and behold the next few days I discoverd a leak .
All sorted but I would not mess with those pipes or hoses unless needed.:)
 
It's funny you should say that I was fiddling about under the bonnet was checking how stable the heater matrix pipes were.
They are not very stable !
And low and behold the next few days I discoverd a leak .
All sorted but I would not mess with those pipes or hoses unless needed.:)

Yep pipes only held in place by 1 screw at heater matrix (O-ring screw) and the rubber going through bulkhead + hoses but they may drag them in a direction...

Wouldn't like to ever change out pipes, think they were one of the first things in the assembly process;)
 
Yep pipes only held in place by 1 screw at heater matrix (O-ring screw) and the rubber going through bulkhead + hoses but they may drag them in a direction...

Wouldn't like to ever change out pipes, think they were one of the first things in the assembly process;)

Metal pipes from heater matrix out of bulkhead then to rubber pipes .
 
The pipes are indexed into the matrix by cut outs. When the clamp is in position they should be quite firmly attached. However if the O'rings are old, twisting, pulling or moving the end that is 18" away is going to find them out because of the leverage exerted on the joints.
 
The pipes are indexed into the matrix by cut outs. When the clamp is in position they should be quite firmly attached. However if the O'rings are old, twisting, pulling or moving the end that is 18" away is going to find them out because of the leverage exerted on the joints.

That's right i only gave them a little wiggle to check how firm they were , as stated over such a long distance that must off disturbed the seals :eek:
 
We live and learn I guess, especially on LandyZone. :)

So I have a 3-4 hour job before I put the interior back together, oh well at least I will know it is done now........ I just wished I had the o rings in preparation for the inevitable leak, I could have done them today.
 
We live and learn I guess, especially on LandyZone. :)

So I have a 3-4 hour job before I put the interior back together, oh well at least I will know it is done now........ I just wished I had the o rings in preparation for the inevitable leak, I could have done them today.

So you have learned to have a box of metric ORings? its a must with a p38 :)
 
The "how to" mentions possibly using hose clamps to save time, although I feel a little concerned over damaging the hoses.

The rad is only 12-18 months old so the drain plug may undo easily.

Anybody any experience on hose clamps on the heater hoses?

Cheers
 
The "how to" mentions possibly using hose clamps to save time, although I feel a little concerned over damaging the hoses.

The rad is only 12-18 months old so the drain plug may undo easily.

Anybody any experience on hose clamps on the heater hoses?

Cheers

If the hoses are in good condition hose clamps will not damage them. If they crack when the hose clamps are applied they needed changing anyway. If you just disconnect them and tie them up you won't lose much coolant anyway. There is definately no need to drain the system.
 
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If the hoses are in good condition hose clamps will not damage them. If they crack when the hose clamps are applied they needed changing anyway. If you just disconnect them and tie them up you won't lose much coolant anyway. There is definately no need to drain the system.

Great news, I hoped that was the case. Thanks
 
Great news, I hoped that was the case. Thanks

That is if you can separate the hoses from pipes, yes just bend hoses upwards and only loose whatever amount of coolant in matrix & pipes.

I have done both methods and will choose to drain anytime as its so easy and not even necessary to disconnect hoses, by blowing into expansion tank you can clear coolant from matrix hence no more than a few drops left when changing O-rings, less mess.

Found no-matter how you do it, it requires more or less the same coolant filling procedure, (unless you fill matrix, pipes & hoses (no air pockets) before reconnecting hoses) also new coolant isn't a bad idea:)
 
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