Heat build up after service

[StanTM]

So, following having a service in which all the fluids were changed, I now have the turbo-side of the engine bay getting a heat build-up that effects the wheel tub, all my intake piping and the section of bonnet above the turbo. It's a large amount of heat and area that is getting to the point of being too hot to touch. I've checked the water and oil levels and they're all topped up, as would be expected after a service.

As I'd rather not cook my ignition pack and have hot intake pipes, can anyone tell me what has happened? I have the thought that it's an air lock in the water system? But where and how to release it ....

[sideways14a]

Could be loads of things.
Is the turbo covered with the stock shield?
Do you have a tubular mani?
Cas not been dicked with (to much advance)?

[StanTM]

No, service didn't touch anything in the bay, noticed the extra heat after I got it back. Turbo heat shield is in place, stock manifold (no heat shield, but thats been off since I got the car, so not that), CAS not been touched.

[Jon]

Random suggestion.

It's July.
Could it be nothing to do with the service, but just the first time you've spent time under the bonnet for a few months ?

[StanTM]

No, I know the normal heat level in the bay and this is significantly more. The wheel tub is really being cooked by it, so much that the outer wing panel where it meets the bonnet is toasty hot. With the amount of wind that gets and the larger than normal heated area of the bonnet, tells me something's wrong.

[sideways14a]

Mods list?

[Jon]

If it isn't the weather, something else has changed.

No, service didn't touch anything in the bay, noticed the extra heat after I got it back.

Fluid changes couldn't do it, but something clearly has.
Did you service it yourself? or someone else?
If someone else, could they have fiddled with the CAS ? They might have tested the timing and thought they were doing you a favour by adjusting it, while cocking things up.
Retarded ignition can generate more heat from the exhaust manifold.

edit:
I just saw 'CAS has not been touched' above.

[M.D.]

The only thing that would cause this is if the timing was altered.

Even if the turbo coolant pipes were removed it wouldn't make a noticeable difference in under bonnet temps.

Have you got any leaking gaskets lately. A slight manifold or downpipe blow can cause lots of heat to escape and warm things up a fair bit.

[ANDY black s13]

They left you a lit propane heater in the glove box then ???,CAS not messed with or an exhaust blow found,what about stock down pipe cat is blocked if you still run one of them horrid things, nothing else in that area can generate heat if the above is good and undisturbed,
check glove box

[haz's s15R]

I'd bet on an air lock mate. The bleed screw/nut is on the block on the front passenger side near where the top rad pipe joins the block. Just slack it off and add coolant untill no more bubbles come out!

[StanTM]

Service done by Abbey MS, so I know they wouldn't do a half arsed job, or f'd around with the CAS without saying. I did consider it might be a gasket leak somewhere, but they are only approx a year old and done by Abbey as well, so I consider that a remote possibility.

I'll give the bleed a try and see what comes out ! Cheers

[ANDY black s13]

Wont hurt to try bleed the system,Is the car pulling/accelerating well for mods if any you have? If your still running cats they can block/fcuk up/move inside and generate massive heat but normally with a huge power loss,which you don't mention it down on power so I'm bit lost for idea's if everything suggested checks out good?
Does it get hot quickly if say started from cold and driven short journey gently? Certainly a weird one so far, If I think of anything I'll check back

[StanTM]

So, bled the system, was a bit over filled with coolant, but otherwise Ok. But it didn't change the problem, still getting very high under bonnet temps. Now thinking it could be a faulty thermostatic valve, or an air lock around the valve. Would I see coolant moving through top of the radiator (looking into the radiator cap pipe) if the valve was opening properly?

[Joe1989]

Breaks binding on perhaps?

[StanTM]

Brakes are reconditioned set all round fitted at service, so I would say no ! It does heat up pretty quickly on the 5mile 20min run into work.

[Mike s14a]

if all theyve done is changed the fluids and filters etc then it has to be your imagination mate the engine bay will get roasty because of the engine and turbo regardless of how hot or cold it is outside

[StanTM]

Na, this is definitely a significant increase in under bonnet temps - I've never had the wheel tub and the hard pipes be so hot that they're almost burning hot to the touch. Before, I've been able to lean on the wheel tub after a long hard run and barely noticed any heat from it - now I can barely get near the metal before the heat starts saying' don't touch this', even after a short warm up whilst standing still !

I'm leaning toward a faulty thermostatic valve, so will whip it out of the housing over the weekend and give it a check over. But can someone please answer my previous question-> Would I see coolant moving through top of the radiator (looking into the radiator cap) if the valve was opening properly?

[Jon]

Would I see coolant moving through top of the radiator (looking into the radiator cap) if the valve was opening properly?

Well, sort of, nearly.
In theory yes, in practice probably no.

Once the thermostat is opening, it is releasing hot coolant into the cold coolant in the rest of the circuit. What will happen is the coolant will expand a bit and overflow out of the top of the radiator. This kind of messes up the plan to 'watch a flow across'.
When the cap is fitted, it can't overflow until the pressure builds to more than the rating on the cap.

If you started with a cold engine and the coolant level in the radiator low, maybe level with the top of the radiator tubes, you might get to see the flow across as things warmed up; though I'm not sure what it would achieve if you did.

[Jon]

Besides, in any month of the year, I think if your thermostat was sticking shut, you'd know about it via other symptoms of melted engine by now, other than hot wings.


Quick question to generate ideas:
This thread started on 12th July.
How many miles have you done since then ? What sort of driving pattern?

[JC SX]

Park either on a hill or jack up the front 12inches then add more coolant to the rad cap till full, squeeze the lower and upper hoses you should feel it flowing
Would you say its more turbo heat or engine block heat? Is it on both wings?