V6 heater return pipe coolant leak advice

[dwhylan]

Hi, I have a coolant leak on the heater return pipe (no.13) at the o-ring end (no.14) in the picture below.

However to get the pipe out the water pump would have to come off and everything else. Or the cylinder head bypass (no.16) has to come off due to the heater return pipe bracket bolt not being removable because it sits in front of no.16.

The heater return pipe runs between the V of the motor under the inlet manifold and the block brace. I had everything off last weekend but didn't want to go any further as I couldn't get to the cylinder head bypass bolts and I don't have the desire to take the water pump out.

I was thinking of cutting the bracket on the heater return pipe and reattaching it somehow or cutting the pipe somewhere along its length then joining it back together with some hose. I don't know about putting a hose in the V of the engine because I don't know how long it will last or how hot it gets in there. I assume it is an aluminium pipe for a reason.

Anyone got any other ideas or any thoughts on fixing the leak, or has any one with the V6 had the o-ring replaced and how much it cost. I thought I could fix it myself and make it easier to fix if it happened again but can take it to a mechanic if I need to.
Thanks
Dylan

[viking shippy]

Hey dyllan what's stopping you from removing the water pump?
If you cut the bracket is there enough room to bolt on a joining strap...ether side of the cut..

[salt36]

Mate I know your pain

Personally I would cut the bracket that bolts to the passenger head if you cannot get that bolt out.
Mine is no longer bolted anywhere and has not leaked or moved. Definitely try and secure it somehow though.

The pipe is soft enough to bend slightly to be able to remove it but I would undo the four bolts and take that centre bracket out, makes it a lot easier to remove and replace the alloy pipe, that bracket only holds the knock sensor, serves no other purpose

I did not bother replacing the 'O' ring, perhaps I should have

Should be cheap from Mitsubishi though

[dwhylan]

I didn't know how much needed to come off to get to the water pump and hadn't done it before plus didn't want to deal with the timing belt.

I will give cutting the bracket a try, might be able to put a joining strap on there. My concern was if it would move too much over corrugations and cause another leak.

Thanks for the tips salt I didn't touch the bracket that holds the knock sensor because I didn't know what it was but it was definitely in the way. I was running out of time by that stage and wanted to get things back together.

I have the O ring, $10 from Mitsubishi.

The leak actually stopped for a couple of days because I loosened the pipe bracket bolt and gave it a jiggle, but this morning I could smell coolant again, will have to check this arvo with a torch.

Thanks for the replies.

Now to take everything back off again. Fun, not.

[Mitsu0069]

I had a v6 pajero in at work sometime ago, with the customer complaining about a coolant leak, after a pressure test, the was coolant running down the back of the block which I thought was from the above mentioned pipe. But it turned out to be the water pump leaking from the tell tail hole , which when your water pump goes, leaks down the valley and out the back of the engine block. Something else to look for if it still leaks after replacing the oring on the pipe.
cheers

[dwhylan]

Thanks, the extra leak I found this morning and was a loose bolt near the front inlet manifold bolt, must have loosened it by mistake and missed it when putting things back together with a torch.

[dwhylan]

Update,
No photos but I ended up cutting the bracket and then bolting in a joiner, very frustrating but getting to it via the intake this was the only option, better because there was some corrosion where the o-ring sat and allowed my to sand it smooth with 2000 grit wet and dry.
The faulty o-ring that was leaking might have been the right size but it looked like it was originally orange in colour that had faded to a near white with some kind of sealant around it, unlike the black/blue replacement.
Got there in the end without paying for a mechanic but it took all day.

Dylan.