Zetec plumbing problem.
Danozeman - 5/10/15 at 09:33 PM
Hi all having put my car back on the road this year I have a problem with it.
It boiled over going into a show a few weeks ago and now I cannot get rid of the air. The thermostat was stuck which I have replaced. Iv also
replaced the expansion tank. It will not keep water in the tank, when revved the water level rises and flows out of the tank and there appears to be
air in the top hose. I was thinking id cooked it and blown the head gasket or warped it. Iv done a block test an all appears fine so hopefully its
ok.
It has always ran a bit hot but never caused me problem since I built it 7 years ago. Only now since I boiled it.
It is plumbed like the picture but iv got the tank and thermostat side pipe T'd in to the same pipe then into the bottom hose.
Whats the best way of plumbing it? Iv read that 'd separately into the bottom hose?
Rescued attachment StevePlumbing.jpg
Ugg10 - 5/10/15 at 09:48 PM
Silly question, did the rad fan kick in and is it turning the right way I.e. Pullin air through the rad, I got mine wired up wrong and it would run
hot even on the move as the fan was on most of the time pushing the air back through the rad.
Angel Acevedo - 6/10/15 at 01:49 AM
Have you dismissed Head Gasket Failure as the problem?
You maight be getting leaks from the bores into the water jacket.
HTH.
britishtrident - 6/10/15 at 06:28 AM
The chemical block test should be enough to eliminate a head gasket from the list but with head gasket failure there is never 100 percent certainty,
Water pump failure would seem to be ruled out.
I would try drill a couple of 2.5mm holes in the thermostat to allow air to bleed.
Danozeman - 6/10/15 at 12:26 PM
the fan is working as it should but it didnt come in when it boiled which was half the problem.
Iv drilled a couple of holes in the thermostat already.
DJT - 6/10/15 at 01:53 PM
Mine's plumbed as per that diagram, except that I have a bleed pipe from the top of the rad to a tee into the expansion tank small pipe.
Works a treat and self bleeds.
88oC Focus diesel stat and 95oC rad fan switch.
I've found that holes in the stat can cause over cooing on colder mornings.
[Edited on 6-10-2015 by DJT]
Paul Turner - 6/10/15 at 02:06 PM
Mine has been exactly as per the drawing below since 2001 and had always worked faultlessly. 88 degree stat in Ford housing and 95 degree fan switch
in top of radiator.
Angel Acevedo - 6/10/15 at 04:51 PM
Another line of thought is that your temperature switch may be malfunctioning.
But, as you have gas (Air) on the system, your fan temperature switch may be working in an air bubble and that prevents it from operating
correctly.
Then, the source of air is the cause.
The head may be deformed just barely to allow the engine to run without a misfire, but enough to let compression gases into the cooling system.
If all else fails, IŽd drain the cooling system, loosen the head bolts and then re-torque the head.
HTH.
Paul Turner - 6/10/15 at 07:38 PM
quote:
Originally posted by Angel Acevedo
If all else fails, IŽd drain the cooling system, loosen the head bolts and then re-torque the head.
Two small points:
Getting to the headbolts on a Zetec means removing the cams.
Zetec headbolts (unless they are some unobtanium specials) are only torque once and replace.
If you decided to go to that trouble you might as well remove the head, only another few minutes extra work.
coozer - 6/10/15 at 08:33 PM
Ok, I had a similar over boiling due to a numb bit by me.
Anyway, the bypass hose, that's the small one coming out of the thermo housing should go as near to the water pump as possible just like the OEM
bottom hose and the hose from the header tank as near the rad on the bottom hose.
What's happening is coolant circulating round the bypass is taking the eassy option up the header tank hose instead of being suckled back into
the water pump.
Danozeman - 6/10/15 at 09:26 PM
Coozer that sounds fair. My t piece is nearer to the bottle that the pump. Il drain it down and change thing around and see what I get. Im fairly
certain there isn't a gasket/head issue.
Angel Acevedo - 6/10/15 at 10:40 PM
quote:
Originally posted by Paul Turner
quote:
Originally posted by Angel Acevedo
If all else fails, IŽd drain the cooling system, loosen the head bolts and then re-torque the head.
Two small points:
Getting to the headbolts on a Zetec means removing the cams.
Zetec headbolts (unless they are some unobtanium specials) are only torque once and replace.
If you decided to go to that trouble you might as well remove the head, only another few minutes extra work.
HA!!
Knew it!!
I was thinking good old last century engineering...
That will pose a problem.
But if the culprit is a warped head due to overheating, that will be the solution.
I hope for the OP to be something simpler.
Keep us posted Danozeman.
AA
coozer - 7/10/15 at 12:59 AM
quote:
Originally posted by Danozeman
Coozer that sounds fair. My t piece is nearer to the bottle that the pump. Il drain it down and change thing around and see what I get. Im fairly
certain there isn't a gasket/head issue.
How far apart are the inputs? Try swapping them round so the bypass is next to the water pump and header to the rad. That should help.
Steve
rusty nuts - 7/10/15 at 05:19 PM
Is the water pump being driven in the correct direction ?
