Alfa 166 revival

blackbox

I've already accidentally posted this in the 156 thread....

Regarding cam belt tensioning on the V6, the special tool works better if you put the lower bolt into the alternator mounting hole (see post 33). This allows it to tighten up against the tensioner mounting rather than the actual pulley (which might get damaged). When tightened correctly the Allen bolt can be tightened to hold it in place. - If you use it as in DGT's photo, access to the allen bolt is blocked.

To use the special tool requires the alternator to be removed, which is even more work.

My recommendation is to follow DGT's "alternative method" using a screwdriver to lever up to the correct tension. Better and simpler and can still be done with the engine in a 166 - I don't know about 156..

i.e. I wouldn't waste money on the tool (again!).

Ded_Zebra

So as most of you know the 166 developed a problem there a couple of weeks ago. Basically developed an engine noise that took for ever and ever to diagnose! Here's a video as a reminder.

https://www.youtube.com/watch?v=AN82CVtrc_Y&list=UU7OsJ2teP2x_5dxV4-OCPpQ

Now I don't have pictures of everything I did because between myself and my dad (blackbox who posted above ) probably put about 30-40 hours into it diagnosing and fixing.
The first thing that we checked was that the engine was timed correctly, as it had recently had the belt changed (about 1000 miles ago) it was suspected that it might have slipped a bit. To time a Busso V6 the engine is set to TDC compression cylinder 1. Once this is done cam blocks are fitted to al 4 camshafts. These go on in the place of the camshaft bearing caps and fit the cam profile and hold the cams in place. We checked and the timing was perfect! Much to the relief of DGT .
The noise was very very hard to pinpoint. It sounded like it was coming from the top end because it was louder with your head above the engine rather than in the wheel well if that makes sense. The engine was re-assembles and ran again. I disconnected the injectors 1 by 1 to see if it made any difference to the noise.It didn't. That ruled out anything with the fuel system at least and also told us that it wasn't related to combustion in any cylinder.
The rocker covers were then removed again, no small task on an Alfa V6!! Couple of hours labour. The camshaft bearing caps were then removed one by one and inspected. As you can see in an earlier post by DGT one of the caps was a bit scored but no where near bad enough to be making that king of noise. Another dead end.
Next was turned the engine on the starter with all the covers removed to see if anything out of place could be seen. Annoyingly the engine made no noises except for when it was running. The starter couldn't turn it fast enough to make the noise. There was a theory that it might have been a broke valve spring, the intake valve stems were easy enough to see through the intakes. All seemed to be following perfectly and none were bent as far as we could see. As well as this all the followers seemed to be following the cams smoothly and correctly.
Next theory proposed was a foreign object in one of the cylinders. We inspected as carefully as we could without removing the heads and everything appeared to be perfect.
We still couldn't really tell if the problem was with the front or rear bank, but because we could easily enough we ran the car with the front rocker cover off. The noise was way louder so that steered us in the direction of the front bank. Almost by chance dad then discovered that one of the hydraulic tappets on one of the intake valves on cylinder 5 was squishy and clearly not full of oil. the culprit was found!!! Just needed to take it out to confirm and carefully compare to the others.
Not many pictures of the first days work due to time pressure but DGT has loads of pictures of the same steps already.
Step one is to remove the timing belt. This should obviously be done with everything in position and as it should be so you can time the belt correctly when refitting.
The next job is to remove the pulley from the camshaft. There is a special tool to prevent the pulley from turning as you release the bolt. Alfa call this the camshaft counter torque tool. Once the bolt is removed the pulley needs a tap of a hammer to release it from the taper.
Then it's just a case of removing the 4 bearing caps and lifting out the camshaft

This is what it looked like with the camshafts in


Now with the cam and the damaged tappet removed


Closeup of where the tappet lives. Good one still in beside it


And the camshaft removed

Ded_Zebra

I had to wait for the new tappet to be delivered. Not too bad at about £15! While I was waiting I thought I would clean up the engine bay so it would at least look pretty :P

BEFORE




Started off with a good cleaning



Down in the valley of the engine was really gross!


To stop water getting down into the intake manifold I found that plastic shot glasses fit in very nicely to seal them





I used a bit of blutac to make sure the seal was perfect


First I hoovered out the leaves and crap with the trusty lidl shop vac and a tiny little hoover nozzle.



Hard to see but here's all the muck I hoovered out



I placed the rocker covers back on and went to town with Gunk and a variety of brushes and the hose. Didn't take any pics with wet hands but I'm sure you know what cleaning looks like!

Upper timing belt cover fitted and you can just about see the power steering mounting bracket fitted now too

Ded_Zebra

Anyway, After cleaning but before being painted with this aluminium paint we have. It's actually great stuff, super thin and gives great coverage however as it's so thin you still have all of the textures of the casting from when the part was made.


After



Before and after



Both looking nice!



Painted the fuel rails gold too. It's a bit of a rough job, not happy with it yet.

Then the new tappet arrived so enough of that arseing around!

Old top and new bottom. The old one is shiny from years of use.



It came pre-primed but I still smothered it in oil before fitting it



There it is beside all its new friends.


Next to fit the camshaft. The bearing caps



The bearing caps smeared with oil



Camshaft sitting in place but not bolted in. you want to get it close to its correct position without turning it if that makes sense? so you don't force any valves against pistons by accident. List it out and juust pop it in in the correct position before bolting in.


Roughly compare to the cam block to check it is close to correct. It doesn't need to be exact yet, just close enough so you only have to turn it a couple of degrees once its bolted in so no valves/pistons will crash.



Then just bolt it in to the correct torque

Then it was the small matter of fitting the belt! Dad was mostly in charge of that and I didn't take any pictures. There is pictures of doing it in the thread already if you look back and are interested:)

Ded_Zebra

Then it was just the small matter of re fitting everything :P

Rocker covers



Spark plugs



Coils



Coils in and connected



Rocker cover cover as I like to call it :P



Injectors connected

Ded_Zebra

Intake runners on. An absolute bastard to fit. Really annoying access to the bolts.The trick is to not tighten them fully yet as it gives them a little bit of wiggle to fit the plenum.



Plenum on. Another bastard of a job. Runners tightened down and countless hose champs secured.



Pipework missing.



Pipework fitted This is where you start to feel like you're almost there but there are loads of annoying little jobs to do



Timing belt covers missing



Fitted



Mounting bracket for power steering reservoir missing



Reservoir fitted and refilled. Hoses connected and clips tightened.



Forgot to clean up this little bracket

Ded_Zebra

Idler pulley for the auxiliary belt



Fitted



Engine steady



Fitted



Fecky little clip.



Fecky little clip fitted



Then fitted the auxiliary belt but forgot to take a picture of that. I was working with a hangover and had been at it for hours and it was getting dark soon too!

Inner wheel well cover fitted


Then the wheel was fitted and the car was finally set down on its wheels again for the first time in weeks!!!

The moment of truth...

Alanstrainor

No worse feeling than realising that all that work hasn't paid off. It's happened to me in the past.

Did it calm down a bit after? Or did you turn it off shortly after the video?

Ded_Zebra

Alanstrainor wrote: »

No worse feeling than realising that all that work hasn't paid off. It's happened to me in the past.

Did it calm down a bit after? Or did you turn it off shortly after the video?

Well as you can probably hear at the start of the video it was grand, running perfectly like. It was running fine when it was just started and then for about a minute. It started again when i got into the car with the video going. I think that tappet mightn't be getting oil. That's why it was initially fine when it was primed going in and then got bad again. Really sucks

Toyotafanboi

do you ever wish for your levin back instead of this Italian stallion :P

i've never heard a dry cam bucket sound quite as aggressive as that, or is the video making it sound a lot heavier than it is?

it's also best practise i believe to replace a full set of buckets as if one is clogged or worn from oil starvation etc, the others may be close behind it in terms of degradation. although i guess that may not be really relevant to your situation and would also be prohibitively expensive on a 24v engine when it is potentially not even the cause :pac:

Ded_Zebra

Toyotafanboi wrote: »

do you ever wish for your levin back instead of this Italian stallion :P

i've never heard a dry cam bucket sound quite as aggressive as that, or is the video making it sound a lot heavier than it is?

it's also best practise i believe to replace a full set of buckets as if one is clogged or worn from oil starvation etc, the others may be close behind it in terms of degradation. although i guess that may not be really relevant to your situation and would also be prohibitively expensive on a 24v engine when it is potentially not even the cause :pac:

Sometimes I miss the Levin alright but it was time to move on. Everything just needed doing on it really very soon and I just didn't want to put it into it.

The video makes it sound a bit worse than it is in real life.

I won't be replacing all 24 anyway. I'm not sure what the plan is really. I'm going away for a few weeks now so should get a chance to stand back and clear my head.

blackbox

It should be possible to assess if the replacement tappet hasn't been getting oil without removing the camshaft. With the previous one we could feel that it was "soft" and may have jumped to the conclusion that it was the tappet that was faulty.

If this does turn out to be the case we will need to figure out a way to clean the oil passage(s). I wonder if pouring WD40 into the area would dissolve the muck? Anny suggestions for a better solvent? There does seem to be rather a lot of muck in the oily parts of the head - obviously it hasn't been fed with Mobil 1 for all of its life.

Ded_Zebra

blackbox wrote: »

It should be possible to assess if the replacement tappet hasn't been getting oil without removing the camshaft. With the previous one we could feel that it was "soft" and may have jumped to the conclusion that it was the tappet that was faulty.

If this does turn out to be the case we will need to figure out a way to clean the oil passage(s). I wonder if pouring WD40 into the area would dissolve the muck? Anny suggestions for a better solvent? There does seem to be rather a lot of muck in the oily parts of the head - obviously it hasn't been fed with Mobil 1 for all of its life.

Cheers dad. Literally sitting on the couch beside you...

Stheno

Ded_Zebra wrote: »

Cheers dad. Literally sitting on the couch beside you...

I was wondering had you developed multiple personalities

toastedpickles

blackbox wrote: »

It should be possible to assess if the replacement tappet hasn't been getting oil without removing the camshaft. With the previous one we could feel that it was "soft" and may have jumped to the conclusion that it was the tappet that was faulty.

If this does turn out to be the case we will need to figure out a way to clean the oil passage(s). I wonder if pouring WD40 into the area would dissolve the muck? Anny suggestions for a better solvent? There does seem to be rather a lot of muck in the oily parts of the head - obviously it hasn't been fed with Mobil 1 for all of its life.

Ded_Zebra wrote: »

Cheers dad. Literally sitting on the couch beside you...

This has made my day, if only my family was like this :pac:

Personally i think its a bloody shame this is happening after the amount of work that's gone into it from all of you guys, i hope you get it sorted out soon

Interslice

****. Feel for you man. Alot of graft there.

dgt

:(:(

I'm still gutted to see this happen to you and only wished it happened under my ownership. Cleaning the galleries is a messy job and if it were me I'd be cleaning all 24 tappets

AMKC

What happened? Did you ever get the engine running right after? Alfa Romeo 166 is a beautiful car have always loved the look of them myself and even now the dash still looks great.