New Motor Overheating

[Hightower]

My new car (1998 Vauxhall Monterey Isuzu Trooper 3.1 TD) is suffering from overheating at speeds above 65 MPH.

I've fitted a new Stat today and after removing the top hose I noticed that there seemed to be metalic bits floating suspended in the water. I've collected it in a jam jar and the water colour is a deepish green. The feel of the water on the fingers is sticky. On inspecting the jam jar a couple of hours after I put it in, the metalic bits have fallen to the bottom. They don't feel like they are metal though.

What could this be.......Radiator leak sealer?

BTW I've run the motor down the motorway tonight and it still overheats, so I guess it's a new radiator for me.

[matt h]

its possibly the water pump breaking up, im not entirely sure but it could be a plastic impellor!!

unless the rad is damaged and or leaking. its unlikely it will need replacing, you can clean it out your self or get it professionally cleaned through,

is it bled ok??

[Hightower]

Yeh it seems to be bled OK. The Rad has seen better days with a number of small areas of missing heatsink fins. So this could be a cause of the overheating, but was worried about the metalic bits I have a container of rad weld sitting on the shelf in the garage (been there years) and the flakes in the coolent water look like the same flakes in the container (obviously not as concentrated.

I'm going to order a new rad off of ebay so should be with me by Thursday.

[Nasher]

I think you're making the right call Andy, though obviously you'll need to flush the system through to get it all out whatever it is.
If the rad isn't that expensive it's worth doing anyway.

As mentioned it could be the water pump, but the higher speed bit suggests to me the rad is blocked.
Does it feel cooler at any point on it's surface? Particularly across the bottom, suggesting its full of something more solid than coolant.

Nasher

[bedajim]

Originally Posted by Hightower

My new car (1998 Vauxhall Monterey Isuzu Trooper 3.1 TD) is suffering from overheating at speeds above 65 MPH.

I've fitted a new Stat today and after removing the top hose I noticed that there seemed to be metalic bits floating suspended in the water. I've collected it in a jam jar and the water colour is a deepish green. The feel of the water on the fingers is sticky. On inspecting the jam jar a couple of hours after I put it in, the metalic bits have fallen to the bottom. They don't feel like they are metal though.

What could this be.......Radiator leak sealer?

BTW I've run the motor down the motorway tonight and it still overheats, so I guess it's a new radiator for me.

When the rads out how much more would it be for the water pump, as having to strip it all out to change it in a few months would really p!ss me off

I'd also do the oil and filters, when the bonnet is open so you know here you are with them too

[Hightower]

Originally Posted by Nasher

I think you're making the right call Andy, though obviously you'll need to flush the system through to get it all out whatever it is.
If the rad isn't that expensive it's worth doing anyway.

As mentioned it could be the water pump, but the higher speed bit suggests to me the rad is blocked.
Does it feel cooler at any point on it's surface? Particularly across the bottom, suggesting its full of something more solid than coolant.

Nasher

I haven't checked the rad temp, but as I'm replacing it anyway seems a bit pointless to try now. But as it was only happening when the cars doing 70, it's cooling down before I could check anyhow. I'll get some flush tomorrow and clean out the entire cooling system before I fit the new rad.

[Hightower]

Originally Posted by bedajim

When the rads out how much more would it be for the water pump, as having to strip it all out to change it in a few months would really p!ss me off

I'd also do the oil and filters, when the bonnet is open so you know here you are with them too

Filters have already been done. A water pump replacement is a good suggestion, I'll check its cost and availability.

[Leapy]

Originally Posted by Nasher

I think you're making the right call Andy...but the higher speed bit suggests to me the rad is blocked...

Agreed. By far the favourite.

Or (dare I mention it), the head gasket is blown and you've got combustion gases getting into the coolant under higher loads

Any sign of gassing into the header tank if you run the engine with the cap off? If there is some gas leakage at low revs you might see it as irregular bursts of gas into the tank.

[Hightower]

Right then!

Bought a Radiator from Ebay at 1am Wednesday morning, turned up this morning when the delivery driver turned up at 8am, now that's what I call service. Great price too, at £93 delivered for a new unit, it was a steal!

Set about replacing it at 12 and job done by 3pm at a very leisurly pace.

There was sludge in the bottom of the expansion tank and obviously some came out the bottom of the Rad. I back flushed the engine block and very little came out.

It definatly looks like some one has used rad weld in some form before as it has all the usual signs and I guess these metalic looking flakes are aluminium flakes used in the rad weld. I just hope that the rad weld was there to fix a leak in the radiator and not the cylinder head or heater matrix

I purchased a slightly more expensive Antifreeze than I would have normally done and went for the Green stuff and at £18 for 5 litres, for this I was expecting gold flakes in there, however when I started to dilute it it was a shade of Blue.....Very weird! I spoke to comma customer service that assured me this was the right stuff, I'm not so sure and feel a little cheated as it's not coloured green (see the pic and make your own mind up).

I held off the water pump as for one I didn't have enough time to buy one and fit it and if the water pump did start to go, I could replace it really easily.

The upshot of all of this is the problem seems to be fixed now.

[Leapy]

That is one tired looking radiator. In fact, it's about as tired as I've ever seen. I wonder if it's planning an autobiography? Could make good reading

[Hightower]

Yes it does look tired

That radiator's core was 14mm thick the new one was over twice as thick at 32mm.

[Nasher]

Well done Andy

Back to enjoying the new motor now then.

Nasher

[Jizm]

All good now then?

[Hightower]

might even do a little boat towing this coming weekend

I guess I'll have to post a new "show us your rig" photo.