Engine Temperature Higher Than Usual

[AGM]

So we have a digital engine thermometer fitted which, up until the last week or so, tended to read in the 70s the majority of the time once warmed up. The last week or so though it seems to have been running a little higher - closer to the 90 degree mark with spikes up to 104. the engine coolant is looking a little low, but is not empty (that'll be the first point of call when we next get to a petrol station). The vehicle has perhaps been loaded up a little more (we've just installed a roof tent), but not sure if this would cause it(?)

Whilst I am guessing this is unrelated, our in-car heater seems to have stopped working as well (blows air, just not hot air) and also the electric windows seem to be a little slow.

Any thoughts on what might be causing this?

Thanks in advance!

AGM

 

[Dave]

A little low? Probably very low!

 

[StarCruiser]

Where are you taking the coolant level AG? In the expansion tank or in the radiator itself?

With no heat, at all, coming from the internal heater I would guess your radiator will be pretty low and you've only been looking at your expansion tank. STOP DRIVING IT UNTIL YOU FIND THE CAUSE be careful about topping up with water/coolant too. As usual, be very careful opening the radiator, hopefully it's cooled down by now but look under the truck for coolant leaks. Should be fairly obvious if it's got hot.

Does yours have the rear heater under the drivers seat? The pipes to these are notorious for leaking on older vehicles. They can be disconnected and plugged with 15mm copper pipe and fittings quite easily at the bulkhead.

Hope you haven't boiled your engine and done damage. Got my fingers crossed for you.
Good luck.
Richard

 

[clivehorridge]

If you hadn't mentioned the coolant level being low, I would recommend renewing the thermostat. In fact I'd recommend that anyway, if you haven't changed it recently.

As for coolant level, as Richard (StarCruiser) said, check it at the radiator cap, but wait until it cools first, or when you release the pressure, you'll have scalding hot coolant spraying everywhere and all over you. It's not pleasant.

The top tank of the rad should be full to brim or up to 1 cm below the rad cap seal. I can say this because for all 10 years of ownership, when I check mine, the level is consistently 1 cm from the seal, and it doesn't lose any coolant and there's no leaks.

If the level is lower, then either you have a leak (and as suggested, the first place to look is the pipes under the truck to the rear heater) or the thermostat isn't opening enough, or you have a leaking head gasket.

(fingers crossed it's not the latter)

Edit: Oh, and BTW I can't think there's any connection between the overheating and the Windows being slow.

 

[StarCruiser]

Windows will be slow in the cold and wet. There's plenty of info on here about new seals and most effectively new motors.

Clive, my truck does the same. Can't keep any coolant in the expansion bottle but it stays around 10mm below in the top of the road. All the time I've owned it.

 

[clivehorridge]

Windows will be slow in the cold and wet. There's plenty of info on here about new seals and most effectively new motors.

Clive, my truck does the same. Can't keep any coolant in the expansion bottle but it stays around 10mm below in the top of the road. All the time I've owned it.

Yep, it's a bit strange, but once you get to know your truck you can breathe easy!

My expansion tank stays pretty much on the mark though.

I only ever had one overheat about 5 years ago, that's when the top rad tank split. I stopped in time thankfully, and a new rad sorted that out.

 

[AGM]

Ok thanks. I had only checked the coolant in the expansion tank and not in the radiator - very low. Have just put in 4 litres of coolant and it's just about full.

I can't see an obvious leak, not quite sure what I'm looking for with the rear heater(?), but will go and have another look in a minute.

Very much hoping I haven't boiled the engine! How do I know if I've done any serious damage?

Out of interest, what sort of temperature should the thermometer be reading for regular operation?

Thanks again!
Alex

 

[StarCruiser]

4 litres of coolant i would be very surprised if you've got away without serious engine damage. This usually causes warping of the head and/or leaks in the head gasket. Others may add to this.

The rear heater if fitted is under the drivers seat. It connects to the main system in the middle section of the bulkhead at high level. There are two pipes that go down from there and run underneath on the drivers side.

As you've mentioned this has been getting worse over some time, it seems you've not spotted it early and been running the vehicle low on coolant. This is never good. There are two ways to lose coolant, internally, into the bores, auto gearbox or oil channels and externally onto the road. The latter is better but neither is good if left and the vehicle is driven as damage can escalate.

Look around all your pipework. Top hose into rad, bottom hose, heater pipes around the bulkhead, follow these underneath and look for sticky sweet smelling patches. Check inside around the dash in the foot wells, check your oil level and if auto. Look also around where the fan joins the engine and below it at the front also check the radiator itself. You should see a leak soon enough if you crawl under.

I'm no expert on temperature but 70 or thereabouts sounds pretty good. Maybe someone can throw some more light on this. It also very much depends on where and what your thermometer is measuring.

 

[frank rabbets]

Get it up to running temperature then park it up on a dry surface. Any significant leaks may well cause puddles so you can trace easily. Those heater pipes rot through and leak coolant so it might be that.

If you take it for a good thrash and the expansion tank does not bubble over it's unlikely coolant is escaping into cylinder/s in which case if you are using coolant it's most likely due to a leak.

 

[AGM]

Thanks again. Just taken it to the only garage that's open and they're saying it looks like a leak around the water pump. Sound feasible?

Anybody know anyone around Bangor who might be able to help?

 

[AGM]

Also - we're currently hoping to drive back to London on Tuesday. Any thoughts on whether we should / shouldn't be going anywhere until we've found / fixed the problem. Obviously we can monitor temperature and carry extra coolant to top up as we go if necessary...

 

[Towpack]

The thermostat specs are...start opening at 74-78 DegC and fully open at 90 Deg. The stat is on the outlet from the rad so your gauge could read higher if the sender is located elsewhere. The coolant capacity of an auto is 11.8 litres but if you've lost 4 litres then the sender could potentially be sat in an air pocket giving a reading that's way out. My experience with leaky water pumps is that they are usually quite small leaks (unless the pump is completely shot) so you may get away with driving it after topping it up fully and keeping a close eye on level and temps. JMO

 

[StarCruiser]

A leak round the water pump sounds feasible. Then there are one or two other items around there that could leak too so until its disassembled the suspect remains innocent in my view. Having said that, it's not a huge job to investigate and confirm the theory.

As for driving it back…if you're on top of it and it's only a small leak and gets no worse, you may be ok. You'll be doing less damage than has already potentially been done.
Personally, I'm not sure I would want to drive it under the circumstances. It really is your call. Open to others experience here.

 

[Bat21]

I've been in the very same situation as you AGM, mine turned out to be a cracked cylinder bore.... I hope yours isn't that bad.

Are you in Bangor North Wales? If you are driving to London from there on Tuesday you will almost pass my front door, I'm near Shrewsbury. Happy to have a quick look for you if you want to call in.

When my problem occurred I was in the South of Spain on the way to Morocco. I continued over the water to Morocco and did the whole trip, my truck was using a litre of water every 100km.

If you are going to drive your truck to London I would make sure you check your coolant level before starting and stop every 50 miles and check the level again, be careful undoing the rad cap.

 

[AGM]

Bat21 - Yes we are near Bangor, North Wales so that could be incredibly helpful. We're trying to figure out whether there's a garage on the way back we could drop it to but if that doesn't work out then it would be great to get an opinion on it. Can I drop you a message tomorrow?

Star Cruiser / Towpack - thanks again for the help. Have run it a little around here and it seems to be OK - any tell-tale signs if the engine's been damaged?

 

[StarCruiser]

Down on power and running poorly. Leaking water internally or from head gasket. Products of combustion in the cooling system (garages have tests for this). Water vapour out the exhaust.

 

[clivehorridge]

If it's due to a leak, then I wouldn't hesitate driving it as long as you stop regularly (every 50 miles as said) to top up. It makes a slow journey but keeps you on the safe side. If you find the loss at that interval is minimal, then you could extend the period.

If the level gets low enough to raise the temp, then it means it's cooling the engine, just stop immediately you see it rising.

It's your fortune if it's the pump leaking, a relatively easy and not too costly fix. On a journey like you're doing, if the head was warped or cracked, I think you'd have problems keeping any coolant in the system for long.

Wish you the best of luck, and it's very good of Paul (BAT21) to offer real assistance, you should call in on him to let him have a look-see if you can.

 

[Bat21]

Bat21 - Yes we are near Bangor, North Wales so that could be incredibly helpful. We're trying to figure out whether there's a garage on the way back we could drop it to but if that doesn't work out then it would be great to get an opinion on it. Can I drop you a message tomorrow?

I doubt you will find any garages open tomorrow.

I will message you my phone number shortly.

First thing in the morning with the engine stone cold, lift the bonnet and release the radiator cap, and then put it back on.
Next start the engine and run it for no more than 30 seconds then switch it off.
Then release the radiator cap again, this time listening carefully for any evidence of pressure escaping.
If there is pressure there then you do have a major problem.

 

[AGM]

Thanks for the tip, Paul. Have messaged you separately and will hopefully see you tomorrow.

Fingers crossed for the test in the morning!

 

[clivehorridge]