Hi DD and BB,

Thanks honey, I confess, (Goodness so many confessions today!) that I didn’t measure the stems. My only excuse is that they were delivered directly to the engineer and fitted by them. The compression though wasn’t limited to just one cylinder the second time, no cylinders were firing. Which puts me right back at making a mistake somewhere along the road with timing or exhaust valve tappet gaps?

Hi BB, sadly again I didn’t check piston height at TDC, it never occurred to me. I did see a slight mark on the piston where the valve was bent, and I do mean very slight. I rotated the pistons and there were no apparent issues, hotspots or scoring, the cylinder walls seem to be in good condition. I guess my overall view was that the engine was running perfectly before overheating and so my focus has been on the head. Like DD mentioned I may be missing something which is affecting timing. I have muddied the water by going on about tappet clearances and shims when they shouldn’t be a factor, except if they really have been swapped around. But that wouldn’t affect all the cylinders.

It’s really helpful getting your opinions because it forces me to look at this from different angles and sooner or later, I will get to the problem.

I can’t promise to travel as far south as Badger51 but I do owe you all a beer!

I’m back in France mid-October and then I will start stripping the engine again. The parts should be jumping off themselves by now!!


E x 2009 Jaguar XF 3.0
2011 Jaguar XF 3.0
2007 LR2 i6 3.2 HSE
1980 Moto Guzzi 850 T3 California

Hello,

A quick post-script to the previous day’s messages, your replies really do make me go back over the work I have done and the signs and symptoms of the problems following each rebuild. I go back through the videos and how my work relates to them. I have to say that I can’t see any discrepancy but that doesn’t mean that I haven’t made a mistake, because somewhere in this is a fault, likely to me mine . As you suggest fuel ok, spark good, engine turning but no compression, a bent valve and the only answer to this can be timing. It affects the exaust more than the intake because the latter are hydraulic with much more self-adjustment ability than the exhaust side.

I’m still, (fairly) certain that the cams are assembled correctly and that the crankshaft is also set in the correct place but I keep going over your advice which, again, points to a timing error. I put on a new timing chain, and I’m sure that was also done correctly. There was some play until I released the tensioner, I wonder if it’s possible to be out by a chain link length? I am struggling to remember every step, maybe I hadn’t bolted the cams, (using the special tool – four brackets), down enough and they were out a fraction. The two-piece cam lock on the front end is at this point only finger tight. If I was out by a few degrees, (the difference between a chain link), would this account for the compression but not trashing the engine by pistons hitting the valves full on?

I know guys, that it is almost impossible to give any qualified answer. The engine is not the most common on in UK/AUS and Europe so most people are experienced in diesel.

As mentioned, my only option is to accept an error and disassemble it again. Of course, this time I have the benefit of a different head/cams/valve cover/ and timing cogs. But unless I can identify where I’m going wrong, I will have the same result?

It would be lovely Christmas present to have FreeDeux back on the road though!

Emma xx 2009 Jaguar XF 3.0
2011 Jaguar XF 3.0
2007 LR2 i6 3.2 HSE
1980 Moto Guzzi 850 T3 California

Emma, You should be able to see if there are any bent valves by removing the cam covers and looking at each valve in turn. If the engine will still turn over by hand I would remove the spark plugs and with a long thin screwdriver or similar check for TDC on each cylinder in turn and note whether the valves are on the point of opening just before the top of the stroke. It might help confirm that the timing is correct(or out). If the replacement head is complete with valves and camshafts I would fit it as is without stripping it down. I would only get a pressure test carried out to confirm its integrity. What sequence are you using when setting the valve clearance?

If the valves are out it’s easy to check by rolling the stems across a straight, a sheet of glass will do if no engineering table is available

If they are bent they will wobble like a wobbly thing drunk on wobbly juice. Regards

David

Lovely i6 has now gone, but not me......

Please let me know if anything in my post offends you, as I may wish to offend you again......

Hi BB,

thanks, that's good advice, no engineers table but I do have a Velux window waiting to go in so I can use the glass on that
Ex 2009 Jaguar XF 3.0
2011 Jaguar XF 3.0
2007 LR2 i6 3.2 HSE
1980 Moto Guzzi 850 T3 California

Velux, great windows



But also best to use a bit of glass that’s not in a frame, and not only roll the valve head and stem tip across, but roll just the stem at the edge of the glass with the valve head “hanging over the edge” you will see very clearly if the stem is bent.

Hope that’s a clear as glass?  Regards

David

Lovely i6 has now gone, but not me......

Please let me know if anything in my post offends you, as I may wish to offend you again......

Hi Emma.

A couple of thoughts but bear in mind I've never had the cylinder head apart so this is mostly guesswork on my part.

Firstly, reading through the thread, it looks like you have evidence that some of the valves have indeed contacted their respective pistons. I base this on the marks on the piston crowns and the bent exhaust valves. Just to confirm, do the marks align (mark on the piston where you would expect the valve to hit)?

If this is confirmed, I can think of only three reasons related to the cylinder head that would cause this:

1. Timing
2. Incorrect valve clearance resulting in the valve being actually open all the time or close to it. This would cause the valve to open further than the 10mm specified in the manual.
3. The removal of enough material from the cylinder head face to cause the valves to extend further into the cylinder space and contact the pistons.

This is assuming that the bottom end is all functioning correctly.

If you're sure that you set the timing correctly, the first thing I'd check is the head casting. The manual says the head height is 149.4mm +/- 0.15mm and the maximum that can be removed by skimming s 0.3mm. You'll probably need a surface table and some measuring equipment to do this and any engineering firm should be able to check it for you. Or you can use a granite counter top and a cheap digital height gauge which would probably close enough. If it's out of spec I wouldn't try anything like shortening the valves as you'll probably run into other issues with timing, plus you don't know if the valve tips are treated. Just scrap it and move on to the second head. Assuming the head checks out as within spec, move on to the valve clearances.

It looks like only the exhausts valves are adjustable so lets start there. Per the manual, it seems like the downside of this head design is that you can't access the cams to see what's happening as the cam cover incorporates the upper cam bearing so it's holding the cams in place. Once you remove the cover I assume the cams just pop up under pressure from the valve springs. Yes/no? If this is the case, you'll need the special tools (303-1235 essentially upper cam bearing blocks) to locate the cams. Go through the procedure in the manual and get all the clearances correct (0.45mm +/- 0.05mm). The manual says to start with the smallest shims available so I guess you do this and then measure the clearance. The actual clearance minus the 0.45mm gives you the amount you need to add to the installed shim - this will be the correct shim size to achieve the required clearance. At this point you should have a head that is within spec and with correctly adjusted valves.

knowing you, this should take you about a day and then you can fit it and time up the engine

Hi BB,
ah the Velux windows, we have six to put in the roof, only had a chance to do two. This is definitely a job for two people as they are triple glazed and I can’t lift it through the frame to attach it. The first one took a whole day the second about a third of that time!

Spooky though we also have a single glass sheet to repair a cracked window in the summer house, (sounds very grand but it’s just a repository for the garden furniture in winter…). I understand your logic on rolling each valve stem and I will check them all.

Hey TFX, how is my favourite person across the pond!! Hope you are in fine fettle.

Digging into the depths of my misty memory, yes, I think the mark on the piston did match the position of the valve. To be honest though my heart sank when I saw it and my biggest concern was that I may have trashed the engine. I rotated the crank and there was no discernible movement on the affected piston and it ran smooth through the cylinder. I also check the feel of the movement against the others and again there was no apparent difference. I also did a rough check that they all came up to the same height by using the depth gauge on a Vernier calliper and they all seemed to be the same. I felt that if they were smooth in movement then I had got away without damaging the crankshaft. I can’t dismiss the mark that was there and so, I guess, there is still a risk damage.

Yes, incorrect timing is a popular suggestion and I have to go back through my process because it is seemingly more and more likely. In all honestly, I would be delighted if I could identify the error I have made. Of course, I would be embarrassed but much less frustrated that I feel at the moment because I would be able to kick myself and then sort the out!

Thanks for the specification of head depth, I can use BB’s glass as a flat surface, although it is a big weight to put on it. I checked the head each time with an engineer’s level, (long, thick piece of metal, not sure what its proper name is) and I will check the one you sent over.

I was able to have a chat with an engineer yesterday, (another machining company) and he very kindly explained that the amount removed would not affect the valve tappet clearances. I have a ball park figure of 3 thousands of an inch removed each time so 6 thou. (0.1524mm). That is within the specification of 3mm. However as with the replacement cylinder head, we don’t know whether the head had been previously skimmed. So yes, I need to measure the depth and as you say if there is any doubt, scrap it and just move over to the replacement. I have to say that I am in any case likely to just use the replacement one as long as I can identify what the problem is.

Yes too, you’re spot on with the effect of removing the cam cover and I do have the tool, (303-1235), to clamp it down. I also made up a couple of tools using an old spark plug welded to a threaded bar. I wasn’t perfectly straight but it did the job in pressing down the cam cover on the cams and so relieving the pressure of the 35 or so bolts used to fix the cover in place. Since then I have located a threaded bar of the correct thread to match the spark plug and I can use this to press the cover down. The bolts are all torqued in sequence as per the manual.

One suggestion and a decent You Tube video shows a process of clearance checking without using the clamp. Although it isn’t a Land Rover or Volvo, I think the principles are the same. He removes all the valve tappets and lays the cam in place. This time it fits in straight. He then puts one tappet in place finds TDC and them measures. It is possible to lift the cam with the feeler gauge but with care it can be checked If that is within spec, he turns the cam to the next position and repeats the process, (after marking the one he has just removed!) That would give me a reasonable idea and then I can go on to lock the cam in position and check each exhaust tappet again. I am worried at the moment that there may not be any clearance at all on some of them.

https://www.youtube.com/watch?v=kCwr55XTOok&t=247s

It confuses me though, (and I have to say reinforces the timing error), that the engine turns over freely, just no compression.

Although the original head had a pressure test, I bought a set of cylinder head plugs in case the overheating had put a leak in one of those. Again, though it seems unlikely to have gone after a pressure test.

A sunny morning here in Southampton after a few days of rain. The autumn has arrived, is it too early to think of Christmas!!!.

Emma xx 2009 Jaguar XF 3.0
2011 Jaguar XF 3.0
2007 LR2 i6 3.2 HSE
1980 Moto Guzzi 850 T3 California

Goodness me!
Another year... CV19, Brexit and auntie Emma's FreeDeux is still poorly....

But first things first. I hope that all you wonderful people are fit and well and having a lovely Christmas/New Year season, despite all the restrictions. I’m writing this, having travelled back to France on one of the last ferries before the cold grey gates of Brexit closed. I do appreciate though, that not everyone sees this as a bad thing. But having a home in France and two dogs I see the downside…
But onto more specific subjects… Auntie Emma’s FreeDeux is still poorly… I rebuilt her, had her running down the road and whilst hitching up the trailer she went … ‘BANG’… actually is was more of a crump then a whoosh…. And a big cloud of steam…
I have learned a lot of things since I worked on this LR2 3.2 i6 HSE. The first is that I am not an engineer, and despite my enthusiasm, and a fairly natural analytical mind I have made a number of mistakes.
I have learned that the team of people who developed the i6 are very intelligent and have crammed a huge amount of technology into a small space. I have learned that the engine and all its systems are quite efficient. I can see the benefits of the READ drive, the fact that the waterpump and steering pump use the same drive point, to reduce size.
It comes down to this:
I had the timing out by 180 degrees and rebuilt the engine three times like this… I made the mistake on the first strip down and repeated (or rather never adjusted the problem on each rebuild) …
I then trapped part of the bottom hose behind the throttle body on the last rebuild. This meant, that as the temperature increased, so did the pressure, as coolant wasn’t being circulated properly. Whilst ticking over, on a hot sunny day, it simply reached a point where something had to go, ‘pop’… and part of the radiator plastic broke. Maybe I hadn’t bled air out of the coolant enough but I saw this error after removing the radiator.
Maybe there were other issues that increased vulnerability but it doesn’t detract from the fact that the main error was mine.
So, here we are on the 2nd January 2021.
I have removed the front bumper, purchased a new radiator and a/c matrix and about to remove the head again to replace some noisy exhaust tappets. I feel that the head is good, the valves are good and everything I com into contact with has been replaced.
Finger’s and all that for a purring FreeDeux in the next week...
Emma xx 2009 Jaguar XF 3.0
2011 Jaguar XF 3.0
2007 LR2 i6 3.2 HSE
1980 Moto Guzzi 850 T3 California

Well done for persisting with it. I would have got rid of it long ago, well actually the first day!

Now I can only spend 90 of every 180 days in Europe on my British passport without a visa. At least I can pop out of the EU & come in on my Australian passport! Procrastination, mankind's greatest labour saving device!

Acoustic insulation ARB TPMS 3xARB air compressors After cooler Air tank On-board OCD pressure air/water cleaning Additional 50L fuel Carpet in doors ABE 2x1kg Waeco 28L modified fridge Battery 4x26ah Solar 120w Victron MPPT 100/20 DC-DC 18amps 175amp jumper plug Awning 6x255/60R18

Lightwater wrote:

Well done for persisting with it. I would have got rid of it long ago, well actually the first day!

Now I can only spend 90 of every 180 days in Europe on my British passport without a visa. At least I can pop out of the EU & come in on my Australian passport!

Emma Scully wrote:

I had the timing out by 180 degrees and rebuilt the engine three times like this… I made the mistake on the first strip down and repeated (or rather never adjusted the problem on each rebuild) …

Hi Jules,
this is the 3.2 i6 petrol. There are videos on You Tube that say that if the locking tools are in place then it's impossible to have the timing out. That's the only excuse I have for getting the same thing wrong and rebuilding the engine three times!!!

I felt truly at a loss. The rear end crankshaft oil seal is removed and a locking tool fixed, the rear end of the camshafts are also locked with a 2 piece locking tool and then the two cogs on the end of the front camshafts are also Iocked. In my trawl through the Volvo forums I found a thread which explained a method to set the timing without the locking tools. It showed that the pistons were in a different attitude, in fact 180 degrees away from mine.... I realised that this was the reason for bending valves, no compression in some cylinders and the reason why my rebuild didn't change anything...

This is what it should be



This is what I had

Click image to enlarge

Click image to enlarge

Emma,

That's an awesome finding

Cylinder 3 and 4 should be at top dead center.

Not cylinder 2 and 5.

You are getting closer

Don't give up

Thanks

Paul