Questions on cooling system and turbo. Bighiorn 3.1d 1995

[270guy]

Hi All,
sorry if this just a rehashed post that you have seen many times before. I did try the search function, but I'm no good at it and I didn't seem to get what i tried searching for.
Here whats happening.... Engine got hot going up the Bombays, let it cool down, checked coolant, seemed ok. Had had no problems during normal day to day driving on the "Flat". I decided that I should investigate, and ended up removing the radiator to check if it was blocked and try to flush it out. Flushed some stuff out, but radiator seemed quite heavy. Put it back together, and refilled with coolant / water, tried to run it up / bleed, seemed ok, but got hot after 10mins driving up the road. Now it seems to get hot all the time, not just on hills . Also When hot, and with revs @ 2500, top radiator hose was pulsing very noticablely. Then if you let it idle or switched it off, the same hose would collapse under vacuum. I seem to have solved the hose thing, with a new radiator cap, but still getting hot after a short drive up the road. Heater blows hot, all the cooling hoses seem to get hot. Don't seem to be any compression bubbles, in the radiator or reservoir.
Now for the questions....
1. Is there a proceedure for bleeding the cooling system on these engines? Is 4JG2T the correct designation?
2. How much should a radiator for one of these weight approx? (I know, I should have had it flushed / checked by a radiator place.)
3. There is a allen key bung in the top of the thermostat housing, is this just a bung for a sensor I don't have?
4. What else should I be checking on this thing? (Waterpump? Thermostat? Trans? Radiator, again? Viscous fan? Head?), And how do I check them?
5. To check the waterpump, you need to take the cambelt off, right?

Thats all that comes to mind right now, and help/ suggestions most welcome.
cheers

[270guy]

Duh, forgot the turbo questions! After turning off the engine, turbo sounds like a 747 winding down. Is it stuffed bearings or something else?

[geeves]

Easy one first. Turbos shot and cant be fixed When it gives up completly replace turbo. Symptoms of complete failure is either lots of smoke or lack of power and overheating
A common problem on these is kinking the bottom hose restricting flow. This would match your symptoms best so check first but also check the thermostat and maybe water pump. They are a large radiator and all copper so are heavy. Any radiator would be way past blocked if you could feel the weight difference. Best test for the thermostat is to take it out and put in a pot of water and put on the stove. If it opens just before the water starts to boil its ok. With thermostat out reconnect the hose fill and run engine If you can see the water movement in the radiator the pump is good.
If all this fails you could be looking at injector pump timing or head gasket problems

[Blondini]

I have come across this before with my sons car and had the same symptoms.
After 3 days of working on it, it turned out to be the water pump. There was no blades left on it.

[270guy]

Thanks for the replies, a job for after work tonight. Let you know what I find. If it is the water pump, do yo need to take the cambelt off, or is it behind the viscous fan? cheers

[geeves]

Its inside the cover but should come off past the belt. Of course if the belts near due you might as well do it at the same time

[270guy]

Ok, so I took out the thermostat, and tested it (pot on the oven). It opened ok as the water came to the boil. I refitted the thermostat housing (no thermostat) and watched for coolant flow, there was flow, so I'm going with the water pump is still working. Another question, the viscous fan, does it have a oneway clutch, or is it supposed to turn both ways with a bit of resistance?
Also, I put the thermostat back in, and started it up. Didn't take long for the top hose to pressurise and get hot. I did let it run for a while without the thermostat, before I put it back in. No obvious compression bubbles in the coolant.cheers

[geeves]

Check the bottom hose isnt kinked.
Viscous fan sounds ok but check it hot as well. When mine failed the fan had resistance cold but freewheeled hot.
A couple of things stand out. First the first time you had problems was the Bombays which are not a big hill Is this the only hill youve been up lately. Second it was ok on the flat until you took the radiator out. This is why I want you to look at the bottom hose.
How do you define hot? If its hot drop a drip of water on the thermostat housing. If it starts steaming after a few seconds its around 90c If it starts to boil after a few seconds its around 100 which would be high but within normal. If it boils straight away it is 105 or so which is ok at the top of a long slow hill with a load but not normal driving. If it fizzes straight away thats too hot and close to the opening pressure on the cap.
Once you are happy its working ok drain and refill with antifreeze as this is also an anti corrosive. If it didnt have antifreeze you may still have a bad pump. The impellor is pressed steel and will rust away if not protected

[270guy]

Sorry, forgot to mention I double checked the bottom hose wasn't kinked. I took the undertray off, and jacked it up, just to make sure I had a good view of the hose. I used antifreeze, when I refilled the cooling system, after putting the radiator back in. So I may still have a possible waterpump problem. Is it possible that the radiator is partially blocked? Is it worth taking it out again and having it checked/ flushed. While its out, doing some more investigation on the water pump - checking for play, easy to turn, or just replacing it? What are they worth? I guess Repco should stock them. I need to get it back on the road.
The whole hot thing, not sure. I'm "stuck" inside looking after our youngest, who is sick, while the boss has a previous engaugement. I could get the radiator out, later tonight, if you think its worthwhile. Thanks for the useful advice, it is appreciated. cheers

[geeves]

To get at the pump its easier to have the radiator out. While its out run a hose through it at full pressure. If the water backs up then there is a problem otherwise its ok but do check the fins from the front for mud and other rubbish

[turnturn]

Feel the front of the radiator while the engine is running. Compare from left to right. If it's blocked I would imagine that the temperature would vary.

[270guy]

Feel the front of the radiator while the engine is running. Compare from left to right. If it's blocked I would imagine that the temperature would vary.

I did think of that, but unfortunately, the a/c "radiator", don't know its proper name, is in the way.

Ok, so I did remove the radiator again, last night. I figured that the overheating got worse after I pulled it out the first time and tried to flush it with the garden hose. I had succeeded in getting some of the stuff blocking the radiator out, but suspected I may have also made things worse . I took it in to a radiator shop today, and asked them to see if it was blocked and if so, see if their could unblock it. Picked it up late this afternoon, they said it was 80 - 90% blocked . So I guess, the flow I saw, without the thermostat, was only 10% or so. Anyway, put the radiator back in, refilled and ran it up, ok, not as much pressure in the top hose this time. Went for a drive, seemed ok, so I carried on to the top of the Kaimais, just to tempt fate . Result ALL GOOD! Temp needle stayed between 1/3 and 1/2 and didn't move, a definite result.
I have another question about the 4wd light staying on, a new issue, but I'll ask it in the correct part of the forum.
Cheers for all the help.

[chrisfnq]

I have had a couple friends who have mixed coolants.. they have had service and mechanic has topped up with different brand.. this has caused the coolants to react to each other making a sludge in the radiator. It caused similar faults to what you have described. 1 looked like a white sludge in coolant.
Happy that you had good result.

[geeves]

All the good books say dont mix red and green coolant. I would go as far as saying once ones been in there you should never use the other for the life of the engine. Red is really only for very new alloy engines. Apart from this brand shouldnt matter

[chrisfnq]

was two different brands of green. apparently one added by mechanic was " biodegradable " added to old standard green coolant.

[geeves]

Both green ones are glycol. One must of been red