Glowing Manifold After rebuild

A

Anonymous

Guest
Hello List, Got a complicated one here for you and hope someone can
help me out. I just bought a GTIR and was sold to me as is and the
bloke told me what it was so i got it cheap. The problem now which
has got me totally confused.

The previous owner told me that he had 4 new pistons fitted to the
car and when he was driving it home the turbo went on the car so he
had a new turbo fitted for 700 quid. Now that the engine runs there
is a problem. If you start the car and let it idle everything is
fine But when you start driving the exhaust manifold which is cast
starts to glow red and looks like the reddest bit starts from the
exhaust on cylinder #2 the water temp seems to be fine in the car
but after a little while the pressure builds up too much and water
starts coming out of the radiator under the cap.

Has anyone had these probs before and if so what was your fix. If no
one has had these problems before then any ideas would be
appreciated.

Regards

Simon
 
A

Anonymous

Guest
could that be from the wrong head gasket being fitted the the engine

;)

Simon
 
M

Mulisha

Guest
Yes, if the holes aren't in the head gasket and they need to be then it could block coolant travel.
 
A

Anonymous

Guest
Thats a hard one and an odd one :lol:

As an off the wall suggestion, is the exhaust or the turbo in some way restricting the flow of exhaust gasses?

If so the exhaust would begin to heat up very quickly, but you should be showing some secondary symptoms such as bad idle, lack of response.

If the cam timing is off this also would cause a similar fault.

As for the cooling system, well lets face the fact that your manifold is 800+ degrees and the combustion chambers will be nice an toasty. Is it not possible that you are just vaporising the water in the cooling jacket surrounding the piston liners?

This is why we fit swirl pots to some cars, the Skyline in particular has a bad habit of vaporising the water at a hot spot in the head on the corner of No6 cylinder. This happens with cars that run high boost.

Oh and cylinder liner diameter, you mentioned that it had new pistons fitted, is it possible the liners have been bored to thin.

I dont think you water fault is the main problem, it wouldnt give you the heat build up in the manifold you describe, its more likely the heat of the manifold/turbo/engine is giving you water system problems.

Check exhaust backpressure, check valve timing, check compresion and check fuel and timing.

On a more linier approach, is the car using water? Is it possible that water is entering a cylinder or more and being superheated and its this thats raising the temp?

Certainly one of the more intresting ones I have seen for a while :lol:
 
A

Anonymous

Guest
will do i shall check all that stuff and get back to you all. i suspected the timing to begin with but then thought if it was that far out then surely the idle and response should have suffed.

simon
 
A

Anonymous

Guest
Just Did a compression test and it is not looking good.
#1 95psi
#2 125psi
#3 140psi
#4 140psi

so regardless to timing the head is going to have to come off.

does anyone have a manual with head removal guildlines and torque setting etc with clearances

simon
 
Fast Guy

Fast Guy

Moderators
Staff member
Exhaust on turbo cars can glow red hot as the exhaust gases can reach upto 1000degsC.
However, you wouldn't expect that under normal driving conditions so chances are it needs a tune up and if it has just been rebuilt, it might not have been set up properly.
Too much ignition advance could be a cause for very hot exhaust gases, also lean fuelling, cam timing, possibly to high a compression ratio or too high a boost for the turbo. (this list is not exhaustive, just what I can think of)
It's most likely the leaking cooolant is a result of the head gasket blowing and the cooling system being pressurised. The exhaust manifold isn't water cooled so a blockage in the cooling system wouldn't make any difference to it glowing.
How was the car performing before this?
 
Fast Guy

Fast Guy

Moderators
Staff member
ruachlodge said:
The previous owner told me that he had 4 new pistons fitted to the
car and when he was driving it home the turbo went on the car
Regards

Simon
Click to expand...
It probably went with the excess heat.
I'd put money on that engine builder making a mistake. (but I could be wrong)

Obvious first things are cam timing and ignition timing that he could do wrong.
If the pistons went cos of the heat it could be fuelling or ignition timing.
 
N

nickg123

Member
Have you got no comeback on the guy who built the engine? Surely he would want to look at it for his own benefit if not yours??

Sounds to me like the head gasket maybe wrong...... this was one thing we spent ages checking on my car before putting the head back on - it's absolutely critical! Even if one of the small holes is blocked it could cause this problem........

As you say - the head has to come off anyway, then i'm sure the problem will be more obvious as right now it could be 1/1000 things!
 
A

Anonymous

Guest
Right i have been tinkering the whole day on this engine. firstly after checking the timing chain it has been put on wrong as the links on the chain are colour coded to match the marks on the crank shaft and camshafts. The links do not match the marks but this does not mean it is out of timing. I then turned the distributor clockwise after fitting it all back together and this has dramatically improved the performance of the engine but the exhaust still glows a bit but not as much as before. So the plan is to change the timing chain and fit it proper to line up with the colours on the links and marks on the pullies. And then set the ignition timing with a timing light. Does anyone know the part number for the chain and how much it costs and how many degrees the timing should be.

cheers

simon
 
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