progress on GU 2.8 over pressure re post 42387

Submitted: Saturday, Mar 03, 2007 at 13:36

ThreadID: 42879 Views:3443 Replies:4 FollowUps:6

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GQ_TUFF

Thanks all who replied regarding my post on the radiator getting air in it, well it went off to west end diesel in Sydney and they did a TK test which has given a negative result for combustion gas, and after lengthy discussions with the mechanic he is not convinced it is a gasket or head. They also pressure tested it which showed up normal but that was done at normal operating temp.

So this still makes me think it has a small leak somewhere that allows air to be sucked in during cool down, but when started again the increase in heat allows said leak to close and give a normal pressure reading. Sounds plausible to me but I am no mechanic.

Basically the advice given to me is to continue to monitor the situation carefully and do a leak down test but he warned that may show negative as well.

After explaining to him it has done it for around 15000km made him feel it was not a gasket as he believed it would have blown the gasket apart by now if it had a leak.

So I am going to replace the hoses as they are soft, put a new thermostat in and play the waiting game.

P.S air locks have being mentioned about this too, could anyone tell me if the GU 2.8 has a bleed screw anywhere on the cooling system, if not a good way to try and remove as much air as possible??

Thanks Stefan

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Reply By: Member - andrew B (Kununurra) - Saturday, Mar 03, 2007 at 14:00

Saturday, Mar 03, 2007 at 14:00

Gday Stefan

Funnily enough I was about to email you to see how its going. My bubble blowing is getting worse, so I am getting it looked at again in a week or so when I get back to town.

I have started negotiations with SWMBO over the Chev, and made some good progress. It will be interesting to see what we come up with over our problems, although mine is looking more and more like a head gasket / head crack, by the amount of bubbles it is blowing now......

I'll keep in touch

Cheers Andrew

AnswerID: 225076

Follow Up By: GQ_TUFF - Saturday, Mar 03, 2007 at 14:11

Saturday, Mar 03, 2007 at 14:11

howd'y again,

You only rebuilt yours not long ago hey?

If you did thats what is causing me some pain, I would have no probs rebuilding the top end if it would give me years of trouble free motoring but the idea of spending $4000 on a new top end and having to do it again in a couple of years does not excatly excite me at all, If it proves to be the big one I will be trading mine in thats it. I am at the stage where I have not sunk big $$$$ into it and feel I should keep it, I could walk away from it and lose $2000 that I am comfortable with. What test are you going to do with yours? leak down? or TK (Co2)???

Good luck mate

Stefan

FollowupID: 486025

Follow Up By: Member - andrew B (Kununurra) - Saturday, Mar 03, 2007 at 14:30

Saturday, Mar 03, 2007 at 14:30

Probably another Co2...

I was hoping for the years of trouble free motoring as well. The first problem of cracked head was due to some overheating, can't really blame the car for that one, although I got no error light and it didn't go all the way on the gage. That one was a new head. The mechanic advised the bores were a little scored, but it would be OK for a fair while. I got a new radiator and thought I'd be right for years.

The second time was a small coolant hose near the oil filter that exploded and dumped All of the coolant, which I didn't detect untin I lost power, as dry temp guages don't work too well. I decided on a full rebuild then as the bores had scoreing before this event(head was machined, not cracked), . I then fitted the low colant alarm (should be std on all cars)

This was about 2 years ago. I thought my troubles were over, so took the plunge on the LPG. I'd noticed a very small amount of coolant loss prior to the LPG fitment, but put it down to an ageing radiator cap. It has now got worse and looking like another head....if I go ahead and fix it.

It sounds like you could be nearing my first stage. Knowing what I know now, after the first head the car would have been down the road...Having said that, the events were not really the car's fault. Some were mine, some were bad luck, and the last one is a mystery. I think this motor doesn't like me, so I think it may have to go. I'd like to get another 6 months out of it, but at what cost.......

If I knew it would be just a head gasket, I could probably get away with about a grand, and get that money back when I sell the motor for a 6.5. If its cracked, 4 grand I will never get back.....

6.5 diesel, 25 grand I will never get back, but I'll have a great car for the next 10 - 15 years at least

Decisions decisions

FollowupID: 486031

Reply By: David from Engine Saver Low Water Alarms - Saturday, Mar 03, 2007 at 19:10

Saturday, Mar 03, 2007 at 19:10

My Better Halfs' last car was an EB Falcon.

It used to dump half it's coolant whenever the wind changed.
No coolant on the garage floor,
No water out the exhaust pipe.
No water in the oil.
Complete mystery.

I tried every test I knew, pressure test, cylinder air tests, new cap, new hoses.
new thermostat, New water pump.
Didn't matter it still did it whenever it decided it would.

The Better Half then told me in no uncertain terms she was unimpressed with my mechanical abilities and took the EB to the RACQ.

It a real test of my character when she returned and declared that they could find no problem either.
I simply kept a straight face and said, "Oh well we will Chemiweld it tomorrow and see what happens"

That product is my hero.

Never lost any coolant again.
I still don't know where the stuff was going but chemiweld fixed it for us.

AnswerID: 225116

Follow Up By: GQ_TUFF - Saturday, Mar 03, 2007 at 19:39

Saturday, Mar 03, 2007 at 19:39

I am heading that way......some goop in a bottle....nothing like a cheap fix!!!

cheers stefan

FollowupID: 486061

Follow Up By: Member - andrew B (Kununurra) - Sunday, Mar 04, 2007 at 08:16

Sunday, Mar 04, 2007 at 08:16

It worked for 700 k in mine, now its started bubbling again (as I said above)....might have to put 2 bottles in this time!

Cheers Andrew

FollowupID: 486109

Reply By: Patrol22 - Monday, Mar 05, 2007 at 13:09

Monday, Mar 05, 2007 at 13:09

Bugger...you guys are starting to worry me. I've got 230000km on the clock now 98 2.8tdi and still not a single problem with it......bubbles where to I look for the bubbles when the engine is running/hot?

AnswerID: 225406

Follow Up By: GQ_TUFF - Monday, Mar 05, 2007 at 19:55

Monday, Mar 05, 2007 at 19:55

Trust me if you had a problem you would know about it, enjoy your good run with your 2.8 mate, there is always goodn's and badden's in every type of car, you only ever hear about the bad ones.....aka 3.0lt sure maybe 200 have blown up, but 1000's have not..

Cheers Stefan

FollowupID: 486401

Reply By: whyallacookie - Monday, Mar 05, 2007 at 15:15

Monday, Mar 05, 2007 at 15:15

Different vehicle but you sound like you have tried almost everything else.

I had a sililar problem with my 300Tdi Discovery. Could not find a leak and the pressure tests were all fine. (CO2 also fine)

May not apply to the Patrol but the Discoveries have an aluminium spacer/bracket that the water pump etc mount on. The coolant runs behind it and through the block. The water pump and I think it is 2 other bolts hold this on but it has a small gasket behind it. Apparently it is common for these to leak because the water pump and bolts need to be tensioned similar to a head, correct order and tourque as you go. (I replaced a leaking water pump and wasn't aware so caused the problem)

Apparently the block and bracket expand at different rates. Sometimes the leak is obvious sometimes it isn't. Might be worth exploring further along the cooling system for something like that. Was the heater core tested?

AnswerID: 225438

Follow Up By: GQ_TUFF - Monday, Mar 05, 2007 at 20:00

Monday, Mar 05, 2007 at 20:00

You could be on the right track, Two people have given me examples of water pumps doing the same thing to their car....opps now 3 lol.....one was a toyota surf....one was a VW of some sort, and now your Disco....The mechanics said to me no way can't be it....been in this game 30 years ect ect ect. So since he is perfect who am I to disagree!!!! LOL. Grave yards are full of people who's doctors were never wrong! I am going to do the pump anyway real soon as its only $100 for one so its worth a shot I reckon.

Cheers Stefan

FollowupID: 486403