Technical Multijet coolant leak EGR?

[bugsymike]

My thoughts were to only temporarily bypass the cooler to confirm that it is the only source of coolant loss 100% then replace cooler with a tested new or second hand good part.
I agree they don't make modern cars easy to work on, the designers may make them cleaner and better on fuel consumption, but I suspect if they were told they would have to repair cars on a regular basis it would concentrate their minds a bit better.
We used to say that about classic minis/bypass hoses and Issigonis, but compared with modern stuff they were a doddle

 

[DaveMcT]

Hi Mike, Ive been looking closely this morning but bypassing the EGR cooler is not as simple as I had expected. The water from the EGR goes into the heater via a 90 degree elbow. It's got those nasty QD fittings that don't release. A pressure test with and without the clamps might be more conclusive.

 

[bugsymike]

Hi Mike, Ive been looking closely this morning but bypassing the EGR cooler is not as simple as I had expected. The water from the EGR goes into the heater via a 90 degree elbow. It's got those nasty QD fittings that don't release. A pressure test with and without the clamps might be more conclusive.

That's a pain, welcome to borrow the coolant pressure tester, fingers crossed it's got your adaptor in the kit.

 

[DaveMcT]

I suspect my glee at finding the EGR is the leak source was misplaced. The clamps on the hoses look secure but the coolant level is still dropping. Pressure tests and compression test are needed.

 

[koalar]

As its needing a lot of topping up

And you say theres no sign of leaks inside or out side of the car

the oil level isn't rising

And it isn't exiting via the exhaust

I'd guess one of the above isn't correct

Is there a clue here
" that but there are no excessive bubbles coming in from the vent pipe"

 

[DaveMcT]

Is there a clue here
" that but there are no excessive bubbles coming in from the vent pipe"

I'm getting worried as losing coolant with no visible leaks usually means head gasket or cracked cylinder head. The EGR cooling hoses are well clamped so flow must be severely reduced if not stopped completely. I thought it had improved after fitting the clamps, but this morning it's as bad as ever. The clamps have not moved. It seems to be worse with the coolant cap screwed down, which has my catastrophe genes buzzing. Oil is clean with no signs of mayonaise and oil level has not moved.

PS - My 100HP has the same coolant tank but it's old and yellowed so I can't see what the vent looks like.

 

[bugsymike]

Just a thought, a simple test with rad cap off we used to do without any equipment was to hold the revs around 2500-3000 rpm then fill the coolant to the brim, often as you backed off the accelerator the water would overflow combined with gaseous bubbles smelling of combustion.
The advantage of a full leak test is it can pinpoint which cylinder is at fault but takes much longer to carry out.

 

[DaveMcT]

Thanks Mike. I will try that.

 

[varesecrazy]

Basic question..

Can you undo the OTHER END of the hoses ??

 

[DaveMcT]

I think Mike's test might have it. Exhaust is clear & no red stain on a white cloth. But water level goes up and down a lot with revs but no exhaust gas smell. I expect it to drop as the water pump speeds up but when done the coolant top was frothy.

Edit - Just found a You Tube video saying that EGR cooler and head gasket can have similar symptoms. He does a bubble test but bypassing the EGR should give the same information.

Does anyone have a tip for removing the QD coolant connectors. The heater connectors are hard to reach and I dont want to cut the hoses. I guess they simply push on in the factory, but what's the trick for removal?

 

[DaveMcT]

Basic question..

Can you undo the OTHER END of the hoses ??

It's extremely annoying. The EGR hoses have the factory clamps and no space to get a tool in to release them. I also don't have a release tool. The EGR to thermostat has a worm clip at the 'stat. The heater to water pump pipe also has a worm clip. So, two short bits of hose with ends plugged could work as end caps to close up the engine cooling system.

I would like to simply(?) bypass the EGR cooler with a straight hose, but the 90 degree QD elbow prevents that and I can't get to the factory clips.

 

[bugsymike]

It's extremely annoying. The EGR hoses have the factory clamps and no space to get a tool in to release them. I also don't have a release tool. The EGR to thermostat has a worm clip at the 'stat. The heater to water pump pipe also has a worm clip. So, two short bits of hose with ends plugged could work as end caps to close up the engine cooling system.

I would like to simply(?) bypass the EGR cooler with a straight hose, but the 90 degree QD elbow prevents that and I can't get to the factory clips.

One type of clip I can undo with special pliers as photo, but there is another that I end up having to twist to the point they break so I can replace with a jubilee clip.
The other one on Fiat I hate is used on their plastic radiators, the idea is you pull back the retaining metal clip and pull the plastic hose end off, all well and good, however if there gets any oil contamination in the coolant like oil cooler on oil filter housing failure in my case, it swells the rubber O ring seal inside that plastic fitting preventing the fitting on of the hose. Fiat supplied O rings are not cheap and if you need to disturb these hoses the oil contamination affects every seal in the water system, when in theory it is a simple push and click on. This type is in my second photo, the hoses are made of corrugated plastic in some places so no chance of making any repair without the genuine part £££s .

 

[DaveMcT]

On the radiator, I simply remove the factory hose clip and replace with a worm clip. I was sad to see a smaller version on the heater pipes - so tucked away you can't get a pliers or screwdriver at them. On a closer look, 100HP has the same, but it has two straight connectors. JTD has a straight and an elbow. It's annoying, I did not think to cut off the factory clips while the engine was out and replace with worm clips.

 

[DaveMcT]

Mike has pulled me out of the do-do. Yay

The car would use a lot of coolant if I drove quickly but next to nothing if I left the rad cap loose or kept to town speeds. We fitted Mike's pressure tester then at just under one bar there was a gush of coolant. from above the gearbox. We got the battery and carrier box off the car to find that I had fitted the short hose from oil cooler with a clip on one end only. It had enough grip on the thermostat spigot to seal under no pressure then let go suddenly. As always, access is horrible but I managed to fit worm clip to both ends.

We topped up the coolant and pumped it up there is a very slow pressure drop but no hissing and no more dribbles (we checked them all with white kitchen roll). Clamps removed from the EGR and no difference in pressure.

When I got back home the coolant level was exactly as it was when we filled it up. Hopefully that's it.

I assume the leak gushed while driving then ran off the warm gearbox quickly dried. Result was no drips to see when crawling around the car.