Felicia 1.3 Cylinder Head Corrosion Around Coolant Ways

[areed]

Thanks for the reply, its reassuring that you think the block looks ok.  Sorry for being negative, my faith in the success of this operation was wavering a bit today - especially seeing how perfect the engine block in that two-part video looked before he put it back together.  This has turned out to be a much more intensive job than I expected, I'm very glad I joined this forum and exceptionally grateful for all of your advice and info so far.  This is my first car, and I've only owned it for ~4 months, so it has definitely been a steep learning curve.

[RicardoM]

Don't worry, nobody was born wise. But after this job you will be too. Meanwhile, why don't you tell us about the events that got you to removing the head?

[areed]

 

 

tell us about the events that got you to removing the head?

 

Soon after I bought the car, I discovered that it was continuously losing coolant.  The lower radiator hose looked suspect, so I booked it in to the local garage to be changed. Unfortunately, it actually failed completely before being changed (while I was 60 miles from home).  

 

I thought then that the problem was over, and the coolant loss resolved.  Unfortunately I was wrong, it was still losing coolant - though much slower.  It would often lose coolant through the cap on the expansion tank, but apart from that I could see no leaks on any of the hoses, the radiator or any of the other fittings (perhaps the system was being over pressurised due to the failing gasket?)

 

At this point I was becoming concerned, and suspected it was the head gasket - but I wasn't sure.  I observed that there was some mayonnaise formed in the filler cap, but I had done several short journeys recently and I understand that these can also cause a build up of mayonnaise even in a healthy engine.  

 

So, I waited until I needed to make a longer journey, before which I wiped away the existing mayo and topped the coolant up.  Sure enough, when I checked the car after the journey there was mayonnaise.  Furthermore, the coolant had not only dropped, but also looked contaminated.  It had changed from reddish pink to a more brownish colour, and had a bit of a skin on it.  This made up my mind that the head gasket was leaking between coolant and oil ways, so I decided I would try to change it.  

 

The video you suggested stated that it was very important to diagnose what caused the gasket to fail.  My belief is that the diluted/lessened coolant due to leaks from the hose corroded the gasket, causing it to start leaking. 

 

As for progress today, I have cleaned up the manifold surface on the head as best I can:

 

And the exhaust manifold:

 

 

Hopefully these are acceptable, because I don't think I can improve them much further.  I have also wirebrushed and wiped the threads with penetrating oil.  I tried two shops for washers large enough to clamp the liners, but had no luck. I will try to get some flat bits of metal from work on Monday for this.

 

I am going to buy a new thermostat housing, this looks like the one I took off, and the part number agrees with the online catalogue as far as I can tell.  Does it look suitable to you?

[RicardoM]

My belief is that the diluted/lessened coolant due to leaks from the hose corroded the gasket, causing it to start leaking. 

 

All your assumptions are correct. The only thing I might add is that this year failed many head gaskets. As if the unusual hot summer chewed them fast. Or maybe their life was due anyway. But nevertheless, too many failed suddenly due to corrosion, not from overlooked overheating. Weird...

 

As for progress today, I have cleaned up the manifold surface on the head as best I can:

 

You did a very good job. Don't forget to clean the threads of the holes for the head bolts. You need a suitable tap and penetrating oil. Then blow out the residues and any moisture from the holes.

 

I am going to buy a new thermostat housing, this looks like the one I took off, and the part number agrees with the online catalogue as far as I can tell.  Does it look suitable to you?

 

There are a few things I don't like in those photos. 1) the sensor has a blue collar in some views and yellow collar in other The right color for 1.3 MPI is blue. 2) it looks very Chinese. I know you are on a tight budget (aren't we all?) but that looks too Chinese.

Here is what I mean by 'too Chinese'. There are two types of thermostats inside: the ones with 'hooks', which are rubbish (see below why)

 

and the ones fixed with a circlip. These are good.

 

Here is a direct comparison.

 

The best buy is this one below. You can see clearly the thermostat, it has the o-ring, no need to buy the sensor so the price is minimal.

[areed]

You need a suitable tap and penetrating oil. Then blow out the residues and any moisture from the holes.

 

I was going to make a thread chaser from one of the old bolts as the other guy did, will that do for this?  Unsure how I will blow the residue out of the holes though, I could try a can of compressed air maybe?

 

The right color for 1.3 MPI is blue.

 

Interesting, didn't realise the colour mattered! Slightly worryingly, the sensor off my car is most definitely yellow.  I have had a hunt for a thermostat housing of the non-hook variety, this is as close as I have come.  I can't see a circlip holding it in, but the metal section of the thermostat looks to be one unit rather than hooked together?  Presumably this will not come with new O-rings for the sensor itself, or for mounting the whole unit back on to the cylinder head. 

Edited 29 November, 2015 by areed

[RicardoM]

I was going to make a thread chaser from one of the old bolts as the other guy did, will that do for this?  Unsure how I will blow the residue out of the holes though, I could try a can of compressed air maybe?

Yes. Yes.

 

Interesting, didn't realise the colour mattered! Slightly worryingly, the sensor off my car is most definitely yellow.

Yeah, it's a mess with those coolant temp. sensors... Never by the book. In fact they are paired with temp. gauge on the dash. Anyways, if it's yellow what you have, yellow must be. But if all this is about that o-ring, use RTV instead.

[areed]

I do want to change the thermostat, was just wondering about the other O-rings. Thanks for the suggestion to use RTV, will look into getting some.  Just cleaned the inlet manifold/throttle body:

 

 

 

 

 

Would have liked to take the throttle body off for this, but there was no suitable replacement gasket in the set I bought so I did without.  

[areed]

Progress update time:

Yesterday morning I cycled to the machine shop, leaving the house at 6am for a 30 mile round-trip carrying the cylinder head in a (carefully padded) rucksack.  I don't recommend this.  Anyway, the mission was successful and the head has been skimmed. Pictures:

Mid-skimming:

 

Post skim:

 

And safely home (it needs cleaning, once I get hold of some acetone):

 

 

It is not perfect, as you can see, but it is better than it was and should hopefully do the job.  The stem seals have been changed as recommended; you were right Ricardo as the seals I had were indeed the wrong size.  Extremely fortunately, the shop had a set of the correct size which they used instead.  So now I think I am on track to get the replacement head fitted this weekend.  

 

I have a couple of questions, though.  The first is which way around do I fit the inlet manifold gasket? The metal around the exhaust holes is wider on one side than the other:

 

 

 

The second question is about the thermostat.  This is the one I took off the car:

 

 

As you can see, it is the hook-together type which you say is less good.  The local motor factors cannot get hold of the circlip style one (including the plastic surround) though as it has been discontinued by their supplier.  So my two options are: buy the replacement hook-in one from them (the make was Gates, if that means anything to you), or buy one that looks like the circlip style off ebay.  Which would you recommend?

[RicardoM]

The manifolds gasket: thicker metal side goes towards the head.

Thermostat: risking to be boring, I will share my practical observations and a bit of theory.

 

First of all, the thermostat is not a part where low price is justified. Best case scenario a stuck open thermostat can increase the fuel consumption by up to 25%. The worst scenario is a stuck close thermostat that in turn overheats the engine and blows the head gasket.

 

Second, a thermostat assembly has to meet the following requirements:

1. to start opening at a specific, precise temperature (88 C in your case) and to be fully open at 100 C
2. to seal very well when it is closed
3. to resist at temperature variations (the housing) and corrosion (the thermostat itself)

Cheap thermostats fail to all three requirements. They are not calibrated properly or lose calibration in time, they don't seal well due to warped surfaces (bad machining or punching), and the plastic of the housing cracks. Corrosion-wise is a disaster. Every failed thermostat I saw was the double-hook type. Never a circlip type.

 

For my car I bought the most expensive I found at that time. It is nickel-plated. Here is a photo.

So I think you know by now what I recommend you to buy. Don't forget that between the head and the thermostat housing there is a smaller o-ring. Check it for cracks. I always put RTV silicone around both o-rings for a perfect seal. Two days ago I had to do that for a Felicia engine that leaked coolant to the back of the engine block from that smaller o-ring.

 

I have one question too: how deep (in mm) did the shop skim the head? Any reason they stopped at that depth?

Edited 3 December, 2015 by RicardoM

[areed]

Thanks for the very detailed reply, sounds like the best option is certainly to replace the unit for one of these non clip-on ones then.  I have found this one which matches your picture, it's not super expensive but not dirt cheap either.  If you think that it looks ok, I'll order one in.  None of the O-rings are cracked, I was planning on swapping them out for fresh ones if I can find the right sizes.

 

As for how much they skimmed, I was told they had taken 12 thou off the head.  Google tells me that this is 0.3556mm; not sure why they worked in inches given I live in the UK.  I think that they stopped there because the guy doing the machining felt that enough had been taken off to do a decent job.  From looking at it myself, most of the remaining pitting is quite deep so I imagine they would have to take quite a lot off to get a perfect finish.  With what they have taken off, the corrosion is now at least confined to the coolant area only - before it extended to the bolt holes etc.  Perhaps they should have taken more off, but I elected to trust the guy doing the work as I didn't know any better.

 

One more question I forgot to ask before, too.  For changing the oil, I understand it is normally a good idea to warm the engine first to lower the oil's viscosity.  Given that my oil is full of rubbish, is this a wise thing to do? I've not done an oil change before, so don't know how important it is for things to be warm.

[RicardoM]

Thanks for the very detailed reply, sounds like the best option is certainly to replace the unit for one of these non clip-on ones then.  I have found this one which matches your picture, it's not super expensive but not dirt cheap either.  If you think that it looks ok, I'll order one in. 

 

That is spot on.

 

As for how much they skimmed, I was told they had taken 12 thou off the head.  Google tells me that this is 0.3556mm; not sure why they worked in inches given I live in the UK.  

 

Umm.... are you using metric now? Because all machines are manufactured before this transition, hence they measure in imperial units.

 

I think that they stopped there because the guy doing the machining felt that enough had been taken off to do a decent job.

 

The other guy skimmed his head 0.7 mm deep and the engine is running great.

 

One more question I forgot to ask before, too.  For changing the oil, I understand it is normally a good idea to warm the engine first to lower the oil's viscosity.  Given that my oil is full of rubbish, is this a wise thing to do? I've not done an oil change before, so don't know how important it is for things to be warm.

 

Since you will be removing the oil pan gasket too, you are good. You can rotate the engine by hand (see how in the other topic) after the oil pan and oil filter are removed to squeeze out most of the old oil.

[Breezy_Pete]

Imperial units are still used a lot in automotive contexts in the UK. Think of wheel sizes for example. Engine builders and machinists generally are still familiar with 'thou', I think partly because working in fractions of an inch, or small decimal quantities like 0.02mm for example isn't very 'intuitive' for want of a better word.  One thou (sandth of an inch) is a useful size to be a 'quantum' and means you can work in whole numbers.

For what it's worth, a handy close approximation is 40 thou = 1mm (error 1.6%). On that basis your googling of 12 thou seemed wrong, so I checked it for you.

12 thou = 0.012".

0.012 x 25.4 (mm in an inch) = 0.305mm.

 

Looks like a good job, and good to have had the stem seals done too.

Edited 4 December, 2015 by Wino

[areed]

Think of wheel sizes for example. Engine builders and machinists generally are still familiar with 'thou', I think partly because working in fractions of an inch, or small decimal quantities like 0.02mm for example isn't very 'intuitive' for want of a better word.

 

Fair! Not encountered precision engineering in Imperial units before, I shall be less surprised next time!

 

The other guy skimmed his head 0.7 mm deep and the engine is running great.

 

That seems like a lot to me! I thought I read somewhere that ~0.5mm was the maximum for these engines, clearly not though.  I will just have to hope that what has been taken off already was enough to restore the ability of the head to hold a seal.  

 

Looks like a good job, and good to have had the stem seals done too. 

 

I hope so!

 

Also just tried to get the old thermostat to move using hot water, first from the tap and then from the kettle.  Thing never moved, so probably was a good idea to replace it.  Incidentally, the dirt on it visible in the picture I posted is pretty horrible, greasy stuff :/

Edited 4 December, 2015 by areed

[areed]

One thread chaser made in preparation for tomorrow:

 

As advised by the internet, I tried to make one side a shallower angle than the other to aid in threading the bolt:

 

[areed]

Cleaned the engine block/pistons today:

 

 

Cleaned the bolt holes with a cloth and the thread chaser, think they are OK although the bottom left one was a touch dodgy in my opinion.  Also drained the oil, the sump gasket I was sold is wrong though so I will have to wait for a replacement to arrive on Monday.

 

Tomorrow I will give the block and cylinder head a final clean and degrease them with isopropyl alcohol (couldn't get hold of acetone, but this should do well enough), then reassemble as much as I can.  

[RicardoM]

Looking good so far. I am sure every little detail will count in the end. If anything in doubt, don't hesitate to ask before torquing the head.

[jonnycilia]

which temperature sensor should i use for the carbed 1.3 felicia lx ? yellow one ?

[areed]

Significant progress today:

Started the morning by cleaning the bolt holes again, both with the thread chaser and with a can of compressed air.  Also turned the engine over several times and wiped out the cylinders to get rid of any dirt that had made its way down the sides of the pistons.  When I was satisfied with the state of the block, I degreased the surface of the block and head, then fitted the gasket:

 

And the head:

 

Then the rocker gear:

 

 

Working out how to use the angle gauge:

 

 

Fitting the alternator bolts and brackets back was tricky.  My car has power steering but no air conditioning, and the auxiliary drive belt has its own automatic tensioner.  The alternator gets in the way of the cylinder head for removal/refitting, and it is not immediately clear how to move it without removing it completely.  The way I did so was as follows:

 

Remove the two bolts fitting the alternator to the bracket (the one on the left has a nut, the other has a hex bit head):

 

 

Next, undo and remove these two hard-to-see nuts/bolts and remove the bolts (This is easier under the car):

 

 

The alternator can now be moved away from the block by levering with a 14mm spanner on the automatic belt tensioner (black cylinder):

 

To hold it forwards out of the way, a thin piece of wood can be put between the alternator and the engine block for it to rest on.  To refit it in position, make sure to tighten the two hard-to-reach bolts last. The top two bolt holes are hard to line up otherwise.

 

Finally, I put back the exhaust manifold:

 

 

And the warm-air collector plate:

 

 

Large jobs left to do now are:

• Refit inlet manifold
• Remove, paint and refit sump
• Adjust valves
• Flush coolant system, refill oil

I am somewhat unsure about doing the valves, any tips?

 

Also, I spotted a scuff/scratch on the drive belt today, which may have been inflicted by me at some point while working (the belt is quite new).  It looks like this, do you think it is serious?

 

Edited 6 December, 2015 by areed

[RicardoM]

Also, I spotted a scuff/scratch on the drive belt today, which may have been inflicted by me at some point while working (the belt is quite new).  It looks like this, do you think it is serious?

The belt could break 10 miles or 10,000 miles from now. It's a gamble. Can you afford a bet?

[areed]

 

 

 Can you afford a bet?

 

Good question! I see that replacements are inexpensive (~£10), only issue I can foresee is finding one the right length for my car's setup.  Is changing it as simple as relaxing the belt tension by shifting the automatic belt tensioner, then slipping the old belt off and the new one on?

[RicardoM]

Yes. The only other thing is belts have an arrow showing the direction of rotation.

[areed]

Excellent, thanks.  I will look into changing it once I've finished the rest of the repairs.  Also thanks for writing the valve adjustment guide, was very informative! I am no longer so concerned about that part of the job

 

This evening I jacked the car up to remove the sump.  Undid all the bolts, but I cannot get the sump to budge.  Any advice for shifting it? Feels dodgy to just go ham with a mallet or try and wedge something between the sump and the engine block...

[RicardoM]

First things first, there are 19 screws. Did you get them all out? If yes, then don't be afraid to use a rubber mallet to hit the oil sump all around. It is very strong, you can even jack up the car putting the jack under it. You can also use a thin blade, like a scalpel or a strong cutter to break the seal.

[areed]

I did take out all 19 screws, yes.  Will try hitting it harder tomorrow evening!

 

you can even jack up the car putting the jack under it.

 

That sounds scary! I've only been jacking on the jack points, and putting the axle stands under what I believe are the wishbone mountings? They look nice and substantial anyway, and haven't broken yet...

Edited 7 December, 2015 by areed

[RicardoM]

That sounds scary! I've only been jacking on the jack points, and putting the axle stands under what I believe are the wishbone mountings? They look nice and substantial anyway, and haven't broken yet...

I know.... it's not in Haynes manual, so it's scary. It's not that I don't know how to properly jack up the car or that we do things in here disregarding completely safety rules or for not having the proper tools or other means. It's just that steel oil sumps are usually tough enough to withstand a heavy impact with a boulder. Now it's up to you if you tap it gingerly for 3 hours or smack it twice with a rubber mallet...