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Puma 1.7 - dead thermostat ?
Ugg10 - 15/5/16 at 03:52 PM

I have finally got round to putting water into my Puma 1.7 Zetec SE that I have in my Anglia 105e and run it for a while to see how it goes.

This is my plumbing - Temp sensors are in the blue manifold at the back of the engine by No4 cylinder.



So after few minutes running both ECU and dash are reading 95 deg C, the ecu controlled rad fan kicks in so all good so far.......

......BUT the rad is cold and the large pipes to/from the radiator are also cold. Small pipes to heater are warm/hot.

So have a I got a dead thermostat (on this engine this is on the inlet side under a black plastic cover halfway down the block near the front of the engine) ? Any comments/ideas gratefully received.

You can see the thermostat housing in this picture


britishtrident - 15/5/16 at 04:43 PM

A bit puzzled by your diagram hot coolant should go out from the cylinder head to the TOP of the rad.
The bottom of connection rad should go to the thermostat inlet.
The header tank plumbing is ok
The heater plumbing looks OKish but the Mini heater like the original 105e Anglia heater is a water valve controlled heater modern heaters are controlled by air biending and have a contiuous flow of coolant through the heater matrix. This could cause problems, unless a by-pass provides enough continuous flow to heater inlet on the thermostat housing when the heater valve is off.


Ugg10 - 15/5/16 at 05:00 PM

Thanks for the info, I based it on the following link with info from madinventions. Iirc the zetec se runs differently to the normal zetec, runs in reverse I think.

For info the heater loop has a 6mm rstricter in it as well.

Http://www.locostbuilders.co.uk/photos.php?action=showphoto&photo=3Zetec%20SE%20cooling.jpg

[Edited on 15/5/16 by Ugg10]


britishtrident - 15/5/16 at 05:49 PM

quote:
Originally posted by Ugg10
Thanks for the info, I based it on the following link with info from madinventions. Iirc the zetec se runs differently to the normal zetec, runs in reverse I think.

For info the heater loop has a 6mm rstricter in it as well.

Http://www.locostbuilders.co.uk/photos.php?action=showphoto&photo=3Zetec%20SE%20cooling.jpg

[Edited on 15/5/16 by Ugg10]


The coolant flow is conventional a lot of engine types these days have the thermostat between the radiator bottom hose and the water pump inlet. With this layout the thermostat depends even more heavily than an old style layout on circulation in the by-pass circuit to open the thermostat ie coolant going straight from the cylinder head back over the thermostat bulb to the water pump without actually going through either the radiator or thermostat. It is especially important that there is no restriction in this flow.


[Edited on 15/5/16 by britishtrident]


adithorp - 15/5/16 at 06:57 PM

Yes the stat is in that black housing but as BT says it's in the return from (rather than feed to) the rad. The hose from there should go to the BOTTOM of the rad and the pipe from the back of the block to the top.


Ugg10 - 15/5/16 at 07:12 PM

Thanks guys, look like I need to do a bit of re-plumbing, may actually tidy up things a bit as a bonus.


nickm - 15/5/16 at 08:45 PM

Hi
I have a 1,6 zetec se in a Sylva J15 mid mounted and it takes a good while to get the hot water to the front of the car, longer than 5 mins sometimes.
I cant remember exactly how i have done the cooling but im pretty sure that the thermostat is at the water exit point from the block and the cold side enters at the low point near the oil filter.

Hope this helps

Nick M


monkeyarms - 15/5/16 at 09:07 PM

My puma engine had a sticking thermostat. Changed it and no problem. My piping is similar to yours, but no heater.


britishtrident - 16/5/16 at 04:41 AM

A lot of builders get confused trying to identify the inlets and outlets on engine water pumps. Car water pumps are Centrifugal pumps, the inlet to the pump is at the centre "eye" of the pump impeller and the rotation of the impeller accelerates the coolant outwards hence "centrifugal pump". The increased velocity of the fluid is converted into pressure by a part of the casing which forms a snail shape called the volute. The shape of the volute smoothly slows down the fluid converting the kinetic energy imparted by the rotor into increased pressure. Pump inlet or inlets always go into the centre pump near the eye of the impeller, the outlet is always round the periphery of the impeller.

You can see the inlet and outlet in this illustration.
https://en.wikipedia.org/wiki/Centrifugal_pump#/media/File:Centrifugal_Pump.png

This annimated graphic shows the outward acceleration of coolant through the pump rotor.
https://en.wikipedia.org/wiki/Centrifugal_pump#/media/File:%28gickr.com%29_97c60aae-518f-9364-2976-166ddaa8685d.gif

This graphic shows a secition through a complete pump.
http://en.wikipedia.org/wiki/Volute_%28pump%29#/media/File:Centrifugal_pump_volute_Richards_1894.png

In this image of a a Zetec SE water pump you can quite clearly see how the casing forms a snail shape which is the outlet volute. When fitted to the Zetec SE engine the coolant comes in from the thermostat to the centre of the impeller then is accelerated centrifugally outwards and colletected by the volute shape of the casing which reduces the velocity and increases the pressure. The coolant then flows out of the volute into the lower part of the engines water jacket. Note how the vanes on the impeller face backwards from the direction of rotation to reduce energy losses due to shock.
http://www.fordpartsuk.com/images_orig/1778516/1.jpg


This image shows it fitted to the engine.
http://www.turbosport.co.uk/attachment.php?attachmentid=38103&d=1256317979&thumb=1


So on the Zetec Se coolant from the bottom of radiator and the by-pass(heater) through the thermstat housing straight to inlet of the water pump. The water pump pumps it out through the volute part of its casing into the lower part of the engine water jacket from where it goes through the engine and back out from the cylinder head outlets into the top of the radiator and heater and by-pass circuits

This design dosen't seem logical to most builders and mechanics but same layout is true of other engines which have thermostats mounted on the lower hose such as the Rover K. This type of layout is very dependant on by-pass flow to ensure the thermostat works as designed.




[Edited on 16/5/16 by britishtrident]


Grimsdale - 16/5/16 at 08:26 AM

if it is the same as my focus 1.6 tivct, (the thermostat is visually identical) it opens at 98°C.


Ugg10 - 16/5/16 at 09:15 AM

Thnks for all the info, much appreciated.

Grimsdale - opens at 98 deg C - did not push it much above this as I thought that was getting a bit hot.

With the warm up circuit (engine / heater / thermostat only) at that temperature the header tank was cold and not pressurised (able to open the header cap no problem). This may add to the diagnosis.

Does the "boil in the pan" technique work with these thermostats - if so I may pull mine and stick it on the cooker hob.

Will also try give the engine a run and see which pipes heat up first to determine the flow route.

Thanks again


adithorp - 16/5/16 at 09:30 AM

Your flow in your diagram is correct. All that needs altering is the connection of hoses at the rad and the T piece (from the bottom of your header) swapping so its still in the bottom hose.

Outlet (hot) from the engine is always at the top and inlet (cold) is always lower. Engine is... inlet cold, heats up, rises, exits (hot). Rad is... inlet (hot) at the top, cools, sinks, exits (cold) at the bottom.

[Edited on 16/5/16 by adithorp]


Ugg10 - 16/5/16 at 09:46 AM

Adthorpe, thanks for the clarification.

If that is the case, irrespective of the rad connection I thought if the warm up circuit was hitting 100 deg C then the thermostat should have opened and I should have got flow through the rad which did not happen.

Cheers

Edit - looks like the thermostat is 82 degs C going on various ebay listings. Will pull it and drop it in some boiling water to see what happens.

[Edited on 16/5/16 by Ugg10]


adithorp - 16/5/16 at 11:16 AM

Putting the stat in boiling water is fine to test it opens. Put a thermometer in the water and you'll know when it opens
Yes, you should have had flow even with the pipes the wrong way around; Just won't be efficient. How were you measuring the temp? It could be as simple as your guage is reading high. A cheap IR thermometer is worth investing in.


Ugg10 - 16/5/16 at 11:29 AM

Temp was from both omex and etb sensors on my 710 ECU and Digidash lite (they were different, ETB higher) and are in the heater circuit at the rear of the engine.

Got a thermocouple on my multimeter so can use that to check temps when I boil the thermostat and possibly for surface temps.


Grimsdale - 16/5/16 at 12:15 PM

re testing in a pan - it will probably work but you cannot easily remove the stat from the housing so you may need a bigger pan. Thermostats are sold complete w/ housing


Ugg10 - 16/5/16 at 01:06 PM

quote:
Originally posted by Grimsdale
re testing in a pan - it will probably work but you cannot easily remove the stat from the housing so you may need a bigger pan. Thermostats are sold complete w/ housing


On the "normal" zetec maybe, but on the Zetec SE it is just the stat as it housed in the engine block.


Jenko - 19/5/16 at 08:30 AM

My set up is exactly the same as the madinventions one, and works perfectly. However, I always had a job getting the stat open just sat idling on the drive way. It may be that specific point of the thermostat is not quite hot enough...My guess is the car is not driavable and you can't run it up and down the road?.

Have you replaced the thermostat / housing, they are a week point. the gasket on the housing often fails.


Ugg10 - 19/5/16 at 11:41 AM

Cheers Jenko, not touched the housing yet, may give it another good idle this weekend to see if I can get it to open up, will give me a chance to have a fiddle with the throttle body balance and the idle fueling and to take some temp readings even if they are only surface, must admit the pipes did not feel that hot to the touch (warm but not hot) will keep a check on them.


Ugg10 - 21/5/16 at 02:31 PM

So, I pulled the thermostat today and it seems to work OK, boiling the kettle from about75 deg up to boiling, the stat open up OK, closes in cold water and opens up again in hot. So looks like I was just not running it long enough.

Also the pump seems to drive the water up through the engine i.e. the hose at the top of the engine get warm before the hose into the pump so will do a bit of re-plumbing to get the hose from the back of the engine into the top of the rad and the bottom into the pump.

That said, found that the thermostat housing was only held on my three bolts ??? and the front oil seal is leaking which is going to be a real pain to fix but will have to do it before I let this any where near a rolling road or an MOT station. Probably easier before I do the plumbing as I may need to take the rad out to do it.

Oh, the joys of project cars but that's why we love them !!!!


Ugg10 - 22/5/16 at 05:28 PM

So, the front oil seal was not as bad a job as I thought. First try, made up a brace bar and with a torque wrench could notmshift the main pully bolt, so in despiration I tried the breaker bar and starter motor trick. Bit scary hut didmthe job, piulley off with a home made puller (luckily the pulley has m8 threads in it), then the cambelt pulley an finally the oil seal removed. Off to ford dealer tomorrow for a new seal.


beaver34 - 25/5/16 at 08:15 PM

glad to see your getting there with it.

other members are correct you need to swap hoses round, other thing is the heater return into the other side of the thermostat housing has a re-stricter in place in a road car other wise its easier for water to go that way and not through the main rad, you do still need to run it as it helps open the thermostat thats what i found with mine anyway


Ugg10 - 25/5/16 at 08:35 PM

Thanks beaver, I have a restricter in the manifold housing at the top rear of the engine, 6mm, rather than at the thermostat housing so hopefully that shoild do the job.

Will try and get the engine back together this weekend and give it another run.


Ugg10 - 5/6/16 at 04:38 PM

What a nightmare !!

Put the engine back together, turned the key, coughed once and would not start.

The online puma/fiesta manual says nothing about the crank pulley bolt being a stretch bolt, not tight enough so slipped, when I took the rocker cover off and locked the cams the TDC was a mile out. AAARRRGGGHHH !

So, new bolt bought, pulleys removed and re-installed and the bolt torqued up right this time (40Nm + 90 degs), cams timed and rocker cover back on. Engine now fires and runs just about. Pulled the plugs, found cylinders 3/4 look OK, 1/2 look a bit wet and sooty, fearing the worst (bent valves) I did a compression test, 9 bar on all cylinders so looks like I ducked one this time.

Next weekend will start to investigate further - air leaks on cylinders 1/2 also now have a rocker cover oil leak so that will have to come off, will double check timing again whilst that is off.

Any other ideas of what will cause this or things to look for gratefully received (for info induction is an ally dcoe manifold with dcoe TJ throttle bodies).

So, not got round to looking into the plumbing other than re-connect it in the correct manner.

Cheers


nickm - 5/6/16 at 09:11 PM

Hi
Checked mine over the weekend i have the cooling system as yours but the head is to the top of the rad as others have noted. I had a 1.7 Puma at the time and i can remember laying it out as per that.
Hope u have esaped with as little damage as possible.

Nick M