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jimnielsen
14-09-08, 22:16
After the first run at the track yesterday - where I was taking the Q4 up to 7000 RPM at each gear change with 1.1 bar boost - I bought the car back into the pits and just turned it off right away. Anyway - after a couple of minutes it started to leak coolant BADLY sorta seemingly from the rear of the engine. After the car cooled down a bit and I topped up the coolant level (about 2 litres :) ). Then when I took the car out again I drove it flat out - then when I bought it back in I opened the bonnet and let the engine just idle for 5 minutes. This time no coolant leak.

questions..

1. where about is the coolant actually leaking from?
2. whey is the color of the water that leaks so rusty when I flushed the system very well after I got it??)
3. do others have to do this extended idle of the car to keep the coolant in?



ambient temp was 20 degrees. water temp was approx 100 deg c when I bought the car back in.

AlfaJack
14-09-08, 22:31
Might be the notorious T piece at the back of the block, it comes off the water pump and leads round to the thermostat but also has a T piece for the header tank to feed it. I find the thread with some solutions.

The water in mine used to be very very rusty. I dont know where it comes from bu I suspect at some time its had water (perhaps no coolant) in it for a very long time without a change and its just gone bad..


No.10 in the first pic:
http://forum.berlinasportivo.org/showthread.php?t=970&highlight=coolant

http://forum.berlinasportivo.org/showthread.php?t=566&highlight=water

wrinx
14-09-08, 23:03
It's number 10 in the second picture :smile: This one...
http://i54.photobucket.com/albums/g118/wrinx/Q4/waterpipes.png

This was my solution to try and keep some angle on the pipe:
http://i54.photobucket.com/albums/g118/wrinx/Q4/SP_A0536.jpg

The worrying aspect is why did yours leak...and then not leak??? You'll have to investigate anyway and that's not a pleasant job!!!


wrinx

arjunior45
15-09-08, 08:23
well, I {my Q4} was leaking coolant fluid from the followings:

a} the tube leaving the expander tank, just under the the EGR tube at the right hand of the car. It was due to the EGR tube that burned this coolant tube in a couple of places.

b} the T piece mentioned from AlfaJack - wrinx - made a T piec in alu.

and

c} the plastic connector for the heater, just under the dashboard to the part towards the engine bay. This one was the hardest to find until this piece went completely apart and lost all the coolant at once. And it was not leaking all the time, just now and then regardless the engine-coolant temperature or any other factor. One day it was leaking when I started the engine for just a minute, the other day with engine hot after turning of the engine, the next day no leak at all and so on.

For the rusty color of the coolant, after having 'flushed the system very well after you got it', maybe is your radiator that it was blocked in a part and was not flushed properly. Can't say for sure though.

Nick

ps. check this plastic heater's connector for the leak.

AlfaJack
15-09-08, 09:46
Forgot about the heater matrix tap - I hate that thing! They do crack and leak - Even if its not leaking, if you do not need a heater then I would cut it out and join the two hoses in the engine bay :)

arjunior45
15-09-08, 10:20
Forgot about the heater matrix tap - I hate that thing! They do crack and leak - Even if its not leaking, if you do not need a heater then I would cut it out and join the two hoses in the engine bay :)

I kept this plastic {why do they did it in plastic?} crap and as soon as posssible I'm going to make one out of alu. And of coarse Alfa dealers here in Greece need a month or so {that means never} for delivery.

Nick

AlfaJack
15-09-08, 10:31
Your going to make the tap out of Alu and still have it functioning with the lever?

jimnielsen
15-09-08, 12:27
I have removed the complete heating / aircon system. However - i don't think that I "joined" the sections that would have gone into and come out of the heater core - i just "blanked them off. Hmmm. worried now..Seems to work ok...

I will check all of the things that you have suggested...

need to fix the steering first.

jimn~

AlfaJack
15-09-08, 12:48
Blanking them off would be alright. Try and get right under the car and inspect the hoses.

arjunior45
15-09-08, 13:50
Your going to make the tap out of Alu and still have it functioning with the lever?

Dear AlfaJack,

I'm talking about the 'connector' part number 60575248 {or 46721718} that is a black plastic two-tubes part connecting the hushes from the engine bay to the heater radiator {inside the car}. This connector was cracked from the engine's part and it was very difficult to see-check it under the throttle body.
Sorry, I do not know how to have a screenshot from the parts cd I have in order to show you the part I'm talking about.

Nick

Juan AR155Q4
15-09-08, 14:41
Jim,
In case the water leak is due to the T hose down the intake, it?d be great if you measure it and post it here.
I?m having a small leak but don?t want to take it out just to measure it. So if you are messing with it, you?ll do me a big favor.

arjunior45
15-09-08, 14:53
wrinx might have the dias as he also made one. Unfortunately I did not kept the dimensions as it was the third time in a week I had to remove the intake manifold to get access to that and I was quite angry for the hole story.

Nick

Evodelta
15-09-08, 17:54
I was taking the Q4 up to 7000 RPM at each gear change with 1.1 bar boost - I bought the car back into the pits and just turned it off right away.

Ummm, probably not the best way to treat an old school turbo car, I'm not surprised it boiled up. :doh:

wrinx
15-09-08, 18:37
wrinx might have the dias as he also made one. Unfortunately I did not kept the dimensions....



Neither did I...sorry :(

I think a lot depends on the type of rubber pipe you use. From memory I made the steel tube about 50mm shorter than the gap but putting the rubber hose on was a PIG of a job!

If I ever take the engine out I intend to fabricate an aluminium hose and do the job properly...the steel was only "temporary" :rolleyes:

wrinx

jimnielsen
15-09-08, 22:21
can you see these pipes / tubes without removing the inlet manifold? - Something I have not done so it sounds daunting :(

jim..

AlfaJack
15-09-08, 22:30
Not easily, you need to look very closely through the gaps in the inlet manifold with a torch.

I have just done the whole remove inlet and put back on job. Takes about an hour and a half to do each - this is as long as you can get to all the jubilee clips from the top that hold it to the rubber connectors.
I will post some pics so you know what to expect.

AlfaJack
15-09-08, 23:25
Sorry thought I had better pics...these might help a little bit..

arjunior45
16-09-08, 09:38
apart the T tube, I had a leak from these tubes too {the 'black plastic connector', part number 60575248}.

Nick

jimnielsen
16-09-08, 09:56
Thanks for the pictures! They will help when I do this job.

Don't you think its strange that the car leaked from this rear 'pipe' and not the 'cap' on the fluid reservoir?

How long should you run the car after driving it (real) hard?

jimn~

AlfaJack
16-09-08, 10:26
Probably a few minutes. Have you installed a fan overide switch like wrinx did, sounds like it would be a good idea. Would really help the turbo cool as I think the water feed to it is directly off the radiator.

wrinx
16-09-08, 11:25
http://myweb.tiscali.co.uk/arocderbyshire/alfaromeo155/index_page/05_Technical/05_technical.htm

wrinx

wrinx
16-09-08, 11:34
Don't you think its strange that the car leaked from this rear 'pipe' and not the 'cap' on the fluid reservoir?


Not really, the pipe has an inherant weak spot where the T joins...see pic below. But, might be worth swapping your cap in case that's not functioning properly.

http://i54.photobucket.com/albums/g118/wrinx/Q4/SP_A0518.jpg

This pipe fits from the expansion bottle to the T-piece:
http://i54.photobucket.com/albums/g118/wrinx/Q4/SP_A0519.jpg

wrinx

jimnielsen
16-09-08, 12:10
Oh, now I see why they don't work so well - I thought that pipe '10' was metal! I will make up a metal one as well.

I will get the "fan" mode done as well - thanks Wrinx...

jimn~

Juan AR155Q4
16-09-08, 17:09
Jim, please take note about pipe 10 dimension and post them here.
I?ll appreciate very much if you do.

jimnielsen
16-09-08, 21:55
I will definitely measure it for you - but it may be a couple of weeks before i deal with this issue.

jimn~

jimnielsen
19-09-08, 04:02
AlfaJack - what about a step by step summary of how to accomplish the removal of the inlet manifold hence providing access to pipe "10"? The manual gives a good guide once the head is off the engine... but I want to disturb as little as possible.

thanks :)

Jimn~

wrinx
19-09-08, 08:15
You don't haveto remove the inlet manifold, it can be done by just removing the throttle body and dislocating your right arm at the shoulder and elbow....least that's how I did it :rolleyes:

wrinx

AlfaJack
19-09-08, 10:59
Removal of head!! Yup I can do a step by step..il start recapping. BTW, are you 100% sure it is this pipe? Well even if its not, its a good one to modify before it does break all together..

Wrinx is right but it is very difficult like that and painful!

1. Remove the straight metal inlet pipe and the 90 degree elbow.

2. Remove the 4 nuts that hold the throttle butterfly. The Throttle cable mechanism will come away now as well with a bit of wiggleing, you might have to manually open the butterfly to the bracket will clear. Put the butterly housing to one side as much as you can - there are 2 water pipes (in and out) which need to be removed as well as a couple of small bore pipes.

3. Diconnect the air temp sensor, and all vacuum hoses and move them out the way as much as possible.

4. Disconnect ERG if you have it.

5. Now the hard bit...look through the gaps closely and see if you can get at the jubilee clips that hold the TB to the trumpets which bolt to the head - there are 8 clipes, 2 on each, if you can undo one for each then it will come off, some of mine had the screw head pointing down and I used some bendy screwdrivers to get at them - was not easy. When I put it back I made sure they all pointed upwards.

6. Remove the two bolts at the front of the TB - they are 10mm and sit at the top of the cam cover.

7. Because the coil packs are attached to the underside of the TB you need to disconnect the spark plug leads so it can come off together.

8. When the clips are all loose and everything disconnected its really just a matter of prising it off the rubber connections and off it comes.


When refitting make sure you connect the map sensor pipe is not snagged on anything - maybe replace it with a high quality piece.

Hope this helps. If I think of anything more I will update.

jimnielsen
19-09-08, 12:48
That's perfect - just what the doctor ordered. No - i'm not certain that that is where the leak came from - but if i pull all this stuff off I will be able to look down the rear side of the engine - the water that came out was very rusty - so I am pretty sure that it will have left a mark that I can see. I am not using the car for a few weeks - so now is a good time to have a look at this issue.

thanks, again.

Jimn~

jimnielsen
20-09-08, 08:04
Its Saturday here - so I am having a go at looking at this coolant leak issue. I have removed the throttle body and I can see that the problem is pipe 10. It seems to be leaking at the small T junction. I can get my arm down there ok (as its small). You can see from the pictures that there is a leak here - you can actually see the water at the base of the small pipe on the "T" that goes back to the filler tank.

The small "jubilee clip" (or hose clamp as we call em' here...) was very loose - so I tightened it using a spanner - so its MUCH tighter now. I can't tell if this is the only problem - or if this has fixed the problem - but it looks like this will have to do for the moment.

I wanted to remove the inlet manifold but the jubilee clips on my Q4 are the factory fitted "clamp" sort that you can't simply unscrew with a screwdriver - and I can see no way that I could ever loosen them without removing the head or the engine.

looking at the situation I could probably remove the pipe 10 without removing the manifold - maybe I should do that - but it may be harder to fit than to remove?

So what do you think? - leave it and give it another run as is? or attempt to remove the pipe 10 and replace it (with a metal one) with the manifold in place??

I had to cut one of the small rubber tubes that goes to the throttle body as the small plastic connector was sorta baked on... where does the other end of this particular hose go to?


jimn ~

Evodelta
20-09-08, 10:04
We have a similar (if not the same) crap rubber T jointed hose on the integrales.
The way I found some high-pressure-only leaks on my track car was to pressurise the system manually with air using the correct tool. You could make your own if you wanted to, you'll soon see the water p*ss out if there are any weaknesses.

The throttle body heater pipes need removing and blanking off at source or (temp job) joining together, it is a good and simple mod for those living outside of the Arctic circle.

If you cannot understand where a pipe comes from or goes to I would suggest following it, otherwise really, there is no hope......

AlfaJack
20-09-08, 10:31
I had to cut one of the small rubber tubes that goes to the throttle body as the small plastic connector was sorta baked on... where does the other end of this particular hose go to?


jimn ~

I think this one goes around the back of the engine bay and in to the fuel vapour system:

http://forum.berlinasportivo.org/attachment.php?attachmentid=320&d=1219594779

As for whether to replace pipe 10 or not. Yours does not look in bad condition but it is a known weak point. On mine, it was weeping so it was replaced but it was a week later that the feed pipe from the header tank burst (90% split). It was obviously weakened by replacing pipe 10. I would say if you have the time to change it blind without removing the inlet like wrinx did then get it done :)

jimnielsen
21-09-08, 22:45
I tightened the hose clamp on the "T" piece of the rubber pipe, but that has made it leak more - so i will remove the whole pipe "10" today and make up a stainless steel one.

Evodelta - thanks for the tip on removing the water in/out pipes to the throttle body - I will blank them off at the source. I was going to ask on this forum if I could delete these pipes but decided that "discretion was the better part of valor" .

SO that will leave only the large rubber tube that goes to the idle control valve as the only rubber tube on the throttle body - which will make it a lot easier to put undo the lower 2 nuts...




jimn~

jimnielsen
22-09-08, 08:14
Jim, please take note about pipe 10 dimension and post them here.
I?ll appreciate very much if you do.

.. Juan.. here are some pictures of the pipe with dimensions as you requested..

cuore_sportivo_155
22-09-08, 08:18
you might need to make some small changes to the fueling tables if your air temp sensor is located before the throttle body. the car will run slightly leaner if there's less heat transferred from the throttlr body. hardly noticeable though, but since you have the tools to do it, and the time as it seems....

jimnielsen
22-09-08, 08:22
When I removed "pipe10" - the one with the "T" piece behind the engine (and yes its really difficult to get it out...) I found that the small T part could be easily rotated with the fingers in the main body of the tube. - that's why it was leaking -

Question: I am not using a heater in this car, the in/out pipes for the heater are blocked off. I plan to use just a straight piece of hose to replace pipe 10 - and then connect the hose that used to go to the T piece onto the now unused heater connection on the metal pipe that joins to "pipe10". Its the same diameter hole, just a bit further along - and at the same height.

anyone see any issues with this approach? it will just make it easier to fit the tube behind the engine and I wont even need to make up a metal T section???

jimn~

Evodelta
22-09-08, 08:52
you might need to make some small changes to the fueling tables if your air temp sensor is located before the throttle body. the car will run slightly leaner if there's less heat transferred from the throttlr body. hardly noticeable though, but since you have the tools to do it, and the time as it seems....

Won't the air temp sensor pick this up and the ECU make the changes itself?

cuore_sportivo_155
22-09-08, 10:26
only if the air temp sensor is located after the TB, which i don't know in a Q4.... on cars with AFM like the 8v and v6, the temp sensor is located there...

Evodelta
22-09-08, 10:29
It is.

Clever people these Marelli guys. :smile:

AlfaJack
22-09-08, 10:57
Question: I am not using a heater in this car, the in/out pipes for the heater are blocked off. I plan to use just a straight piece of hose to replace pipe 10 - and then connect the hose that used to go to the T piece onto the now unused heater connection on the metal pipe that joins to "pipe10". Its the same diameter hole, just a bit further along - and at the same height.

anyone see any issues with this approach? it will just make it easier to fit the tube behind the engine and I wont even need to make up a metal T section???

jimn~

Interesting idea. I think you would be fine with that. Its only a feed for the engine after all, I am no expert though. But I would try it and see how it goes.

Juan AR155Q4
22-09-08, 14:55
Thank you very much Jim!!! That?s exactly the info I was needing.
As for connecting to the heater, I don?t think you?ll have trouble, as they are at the same height.

cuore_sportivo_155
22-09-08, 15:20
It is.

Clever people these Marelli guys. :smile:

maybe... the closer you get to the engine, the more heatsoak gets to become an issue...

You'd want the temp sensor as close as possible to the engine, without the sensor soaking up the heat from it, through radiation or conductance... not as easy as it sounds :)

In my reworked 8v the temp sensor will sit right in front of the TB.... but since i'm going aftermarket with my ecu i can tune it any way i like...

jimnielsen
28-09-08, 03:15
And finally.. when I put all the pipes and everything back together - I decided to leave out bolt "25" as seen in this picture.... seemed to me that the pipe was well enough supported...

As it turns out, bolt 25 goes through to the water jacket in the block.. so it took another hour of taking all the turbo pipes etc off so I could install it! :)