Water pipe rusted and leaking - help!

[fgin]

First time poster but I have been lurking here reading great stuff.

I have a 99 NL and found a small water leak at the top and today I took out the piping and see that its rusted and needs a new pipe + o-rings as you can see below.



For reference, I didn't have to take out the intake. Just the top part of the thermostat and then wriggled/levered out the back from the engine. Hope the pics helps someone else in future. I cleaned up the rust that was on both the ends that the rusted parts met. Hence you see it clean. Hopefully a new pipe with new O-rings are all I need.

where is the best place to source this pipe and o-rings from? Will Autobarn, Supercheap, Bursons etc be stocking these? What's this part called ?

PS: If anyone has a spare pipe in useable condition I can buy then please PM me, Im in SE Melbourne.

cheers

[Downunder35m]

Part number should be MD359418 and the thing is called "Pipe, cooling water outlet" - hope that helps...

[fgin]

Part number should be MD359418 and the thing is called "Pipe, cooling water outlet" - hope that helps...

Thanks mate, Any idea where I could source this ?

[Downunder35m]

Well it is a Mitsu part number, so one source would be a Mitsu dealer
If you can't find anything at the wreckers you can try to refurbish the oldp pipe:
Clean loose rust with a wire brush, for the inside you mighthave to "misuse" a broken lawn trimmer.
Cut one end of the flexible drive shaft off with an angle grinder.
Use some force and good pliers to fry open the end so the single wires have no problem reaching to inside walls of your pipe.
Put it in a drill at low speed and feed it through the pipe until no more rust falls out.
Use sandpaper on a silicone hose to smooth out the areas for the rubber rings. Part number for them is MD030764 by the way...
Once you are satisfied with the smoothness for the ring area seal one end with a rubber glove, ballon or whatever you have around and fill up with Phosphoric acid - let sit over night.
All remaining rust will be gone and turned into a corrosion resistant phosphate layer.
You can do the same on the outside with a sponge if you don't like paint.
The acid can be filtered and stored for later use.

[fgin]

Well it is a Mitsu part number, so one source would be a Mitsu dealer
If you can't find anything at the wreckers you can try to refurbish the oldp pipe:
Clean loose rust with a wire brush, for the inside you mighthave to "misuse" a broken lawn trimmer.
Cut one end of the flexible drive shaft off with an angle grinder.
Use some force and good pliers to fry open the end so the single wires have no problem reaching to inside walls of your pipe.
Put it in a drill at low speed and feed it through the pipe until no more rust falls out.
Use sandpaper on a silicone hose to smooth out the areas for the rubber rings. Part number for them is MD030764 by the way...
Once you are satisfied with the smoothness for the ring area seal one end with a rubber glove, ballon or whatever you have around and fill up with Phosphoric acid - let sit over night.
All remaining rust will be gone and turned into a corrosion resistant phosphate layer.
You can do the same on the outside with a sponge if you don't like paint.
The acid can be filtered and stored for later use.

Thanks mate, that's really helpful and detailed info. I will try the dealer and wreckers as well.
I am up for refurbishing the existing pipe but the problem is the o-ring areas have disintegrated. One on front has only half the channel left where the o-ring fits. The back one is almost gone. I think if I try to remove the existing o-ring it will disintegrate further. Which is why Im thinking I should try to source a better/new pipe.

[Pauly Faulkner]

There was a few new ones on ebay a few months ago.

I'll have a look soon and see if I can source you one for cheap.

[TC.Barky]

Whatever you end up doing with the pipe, I'd recommend genuine o-rings. There's been problems with aftermarket o-rings leaking (even from top notch brands) and they are only a couple of bucks from mitsu. Personally I'd have a crack at fixing up the pipe with downunders instructions if you can't find a better one from a wrecker for cheap, the rust doesn't look super bad on the pictures.

[Downunder35m]

This should be suitable rings, but for the pipe itself I think checking the wreckers first is the best option.
If you still have a complete ring you can taki it to Reese or any other plumbing joint, they should be able to supply it cheaper than Mitsu dealers.

[Pauly Faulkner]

I had a few same ID but thicker gauge in a kit I bought years ago, I used them as they were ever so slightly thicker as I was having troubles even with genuine O-rings. Not just my car either, was having the same issue with a few other cars I serviced. Snotting the recessed groove and the backing plate snout with rtv did the job but one day it clicked to see if I had a thicker one and sure enough I did and never had the issue again. I used the last one on mine when I did my rebuild late last year.

The part number for the pipe he is after is MD359417, numbers have been revised for all NL SOHC(there was three part numbers in total between 1997-1999 but this is the latest and is also the revised number for 1997 and 1998 NL).
New genuine one found here http://www.amayama.com/search/?q=MD359417&cur=AUD

[fgin]

Whatever you end up doing with the pipe, I'd recommend genuine o-rings. There's been problems with aftermarket o-rings leaking (even from top notch brands) and they are only a couple of bucks from mitsu. Personally I'd have a crack at fixing up the pipe with downunders instructions if you can't find a better one from a wrecker for cheap, the rust doesn't look super bad on the pictures.

Thanks for the heads up mate. Personally I'd prefer to fix it too, but, the pipe has disintegrated on one side (top of engine) where half the o-ring recessees grove has rotted away and crumbled. So there is no where for the o-ring to sit on.

This should be suitable rings, but for the pipe itself I think checking the wreckers first is the best option.
If you still have a complete ring you can taki it to Reese or any other plumbing joint, they should be able to supply it cheaper than Mitsu dealers.

I might've found a used pipe from a wreck, says it was replaced only 12 months back, I will go check it out today. Asking $20 so not bad I suppose.

I had a few same ID but thicker gauge in a kit I bought years ago, I used them as they were ever so slightly thicker as I was having troubles even with genuine O-rings. Not just my car either, was having the same issue with a few other cars I serviced. Snotting the recessed groove and the backing plate snout with rtv did the job but one day it clicked to see if I had a thicker one and sure enough I did and never had the issue again. I used the last one on mine when I did my rebuild late last year.

The part number for the pipe he is after is MD359417, numbers have been revised for all NL SOHC(there was three part numbers in total between 1997-1999 but this is the latest and is also the revised number for 1997 and 1998 NL).
New genuine one found here http://www.amayama.com/search/?q=MD359417&cur=AUD

Where can I source these thicker O-rings ? If I use the thicker ones there is no need for RTV?

Again thanks for all you help guys. I will report back once I see/get the pipe.

[Downunder35m]

I had to get some parts from my local bearing supplier and took the liberty of asking for rings
Don't ever walk into such a place and ask for rubber rings!!
They had their funny day today and asked if I already checked the adult shop down the road....
After the jokes I was told there are too many types sizes to pick without proper measurements.
So they recommend to bring an old ring or a pipe without corrosion to check for the right diameters.
Most rings can ordered in Nitrile as well, they offer superior wear resistance compared to the standard rubber rings and stay softer much longer.
Prices are only a few bucks for two rings.
So you might want to check if you have any good shops around as it makes finding a proper oversized ring much easier.

[fgin]

I had to get some parts from my local bearing supplier and took the liberty of asking for rings
Don't ever walk into such a place and ask for rubber rings!!
They had their funny day today and asked if I already checked the adult shop down the road....
After the jokes I was told there are too many types sizes to pick without proper measurements.
So they recommend to bring an old ring or a pipe without corrosion to check for the right diameters.
Most rings can ordered in Nitrile as well, they offer superior wear resistance compared to the standard rubber rings and stay softer much longer.
Prices are only a few bucks for two rings.
So you might want to check if you have any good shops around as it makes finding a proper oversized ring much easier.

I feel your pain. Thanks again for trying. There is a Reece not far from my place. I might try them for some thicker o-rings once I've cleaned up the pipe I (might) get this afternoon. i will ask for Nitrile.

[Pauly Faulkner]

Try and make sure the ID of the oring actually touches the pipe. If it doesn't then it might just buckle instead of compress when forced into the backing plate.

[fgin]

Try and make sure the ID of the oring actually touches the pipe. If it doesn't then it might just buckle instead of compress when forced into the backing plate.

Thanks mate, will do, I will be hunting for thicker O-rings tomorrow. When you fitted thicker o-rings did you still use RTV or any other sealant? What would you do with this pipe considering its condition? Any other suggestions part from Reece to source the o-rings?

Got the pipe this afternoon, it's a vast improvement from my existing one, however it has some rust too. Here's the difference after I cleaned it up.

[Pauly Faulkner]

nah mate I just put the thicker oring on and that was the end of it.

That pipe looks half decent, better then mine anyways.
Just make sure you flush the whole engine and heater out with the hose and fill with concentrate(not pre mix!!). It's important to have the right mixture or the same problem will just happen again but sooner.

I use the one that makes just over 9litres. Poor the whole thing in the rad then top up with water from there.