Technical Engine Timing setup 1.4 8v VVT

[QuboPete]

Hi GrandePunto PL

OK here goes:-

Take 1
I am confident that I made the first incorrect set up by failing to realise that the VVT pulley wheel outer had shifted its position (possibly back to its default locked position) whilst the cam was out for the head gasket job. During this attempt, I had locked the flywheel ring gear (and thus hopefully the crankshaft) and the cam end slot with my home made tools before removing the belt and the head. I had also left the VVT pulley wheel secured to the cam. I left the ring gear (crankshaft) lock in place whilst I reassembled, and the belt went back on with the front run taut and with my cam end slot lock in place. I was thus convinced everything had gone back as it had come apart. I guess any shift in the VVT pulley must have been exactly a full tooth (or exactly several full teeth) for this sense of false security to have arisen. A slack belt front run would have set the alarm bells ringing.

Take 2
I achieved the second incorrect set up using the correct locking tools and following guidance from various locking tool manufacturer's instructions, including the instruction to slacken the VVT pulley bolt. A double check after tigtening the pulley bolt and turning the engine 2 complete revolutions by hand saw the locking tools go back in OK. This attempt failed possibly because the VVT pulley hadn't returned to its default position. It maybe that the ECU had tried to sort out the incorrect cam position from 'Take 1' and this had left the (still oil filled) pulley in a different position. The recheck with the tools after running the engine saw the cam retarded. The other possible explanation is slippage of the VVT pulley on the cam during running due to incorrect assembly techniques - see my post of 4/1/25.

Following the excellent guidance from you on cleaning and testing the VVT pulley default lock with compressed air, and observing your graph traces of its movement during a test run have been instrumental in the apparent success of 'Take 3'. I think it remains a possibility that the VVT solenoid valve may have developed a fault that may have contributed to the pulley settling in a random position with the engine stopped, and thus to an incorrect timing set up.

I cannot thank you enough for sharing your obviously hard won professional experience. I am just an amateur whose enthusiasm often exceeds my abilities!

Kind regards

QuboPete

 

[GrandePunto PL]

OK. That is interesting case study and lesson for everyone: pay attention to details like that (is your VVT at "home" position etc.), watch out for traps.
Those VVT actuator wheels act like an oil centrifuge. There is a dirt accumulating inside. Hard to wash out.
Full cleaning is possible only if you disassemble whole thing. There are videos on YouTube (go figure).

Kerosene (lamp oil) soup.

Collect the debris and test with magnet... A lot of magnetic stuff.

Next, pop the rotor. The o-ring size is 100 to 105 mm range diameter (both will fit), thickness 2,5 mm.

Wings/flaps/arms (whatever) can be worn and rattle around. This is the internal leak source (and VVT noise, rumble during startup).

Wear pattern, "witness marks". Technically possible, but not economically viable to repair. Buy new VVT wheel.

By the way. The camshaft seal can cut the groove in the VVT wheel. This could be restored (but also not a cheap option for an average Joe).

Micro-TIG welding, my test piece (junk VVT wheel). Not pretty (there are some defects, like "undercuts"), but acceptable.

Test cut (lathe) and quick polishing. Good for a very first attempt. There is a room for improvement.

Nominal size is 40,00 mm. There is an (0,01 mm) excess "meat" to grind/polish.

Check also latest Guide Discussion posts: https://www.fiatforum.com/threads/1-2-8v-evo-2-engine-cam-belt-replacement.237966/post-4763155 !

And if your engine looks like this, don't be "surprised" when (multiple) problems occur. People neglect their cars and then play dumb. Get a grip, mate.

More entertainment like that can be found on YT, "Just rolled in" channel: https://www.youtube.com/@JustRolledIn/videos!

 

[QuboPete]

Hi GrandePunto PL

Many thanks for your interesting post of the dismantled VVC pulley and your repairs. That's a fantastic welding / remachining job. There will come a time in the not too distant future when new VVC pulleys are no longer available, and commercial remanufacture becomes uneconomic. Such repairs will then be the only way of saving a whole car.

The dirt centifuge effect in the VVC pulley is an interesting point. Most early Honda motorcycles used crankshaft mounted or crankshaft driven centifugal filters to good effect. Without them, the centrifugal big end oil feed galleries in the inner crank webs would have become blocked in no time.

I'm glad I have never bought into this long recommended service intervals nonsense - its a marketing ploy by marketing men who don't care how long an engine lasts beyond the warranty period. I have logged 12 oil changes in the 40,000 miles or so I've had the car. I think I am reaping the rewards as my engine looked pretty clean judging by some of the examples you have posted.

Thanks again for all your help and to other contributors for their valuable advice. I'll be making a contribution to the Forum kitty.

Kind regards

QuboPete