(T) Broken down various fault codes

Cheers multipete. By massive is that more than a few mm or is it going to be really obvious as soon as I get the rocker cover off?

Yes this is what I would expect, based on all the eLearn technical information.

However I've not actually comes across or been in contact with anyone who has had a cam belt fail on the 1.9 16V MJet engine or discussed this with any Fiat master tech.

In theory when the belt fails the valves, driven via rocker arms, as compared to a true overhead cam engine, are designed to fracture. For this to happen 100% successfully then the piston face and valve face must be absoluted 100% paralell to each other and the valve stems not suffer shock/compression expansion.

With a bit of luck Brian all will be well. You won't know 100% unless you were to completely strip the head down, bench roll valves, test valve seat laps, etc etc.

Best you can do is replace broken rockers (I would suggest all as some may have had a lite, semi hard shock but not fractured) and then run a compression test. You could skip compression and go for driver performance.

"The Choice Is yours" as they say

Thanks s130. Had a go at getting the rocker cover off but am struggling, partly because it's now dark, cold and still very windy.

I got the 6 torx bolts undone no problem and the small 10mm bolt that holds the small bracket undone easily as well but what else would be holding it in place?

Another rookie question - do I need to remove the injectors?

I can't find a YouTube video for this engine anywhere.

Brian

The Croma eLearn is on this website.

See:

https://www.fiatforum.com/downloads....downloadid=373

Will/should have everything you need to know.

Got the rocker cover off, nothing like having a bit of daylight to see what you're doing.

My 8v 1.9 engine doesn't seem to have rocker arms and I couldn't see or hear anything particularly awful.

When turning the cam it makes a kind of slurping sound but no grinding or any other kind of noise.

I'm going to get a dayco timing belt kit from ecp tomorrow (don't want to risk another skf kit) and with an awful lot of luck maybe I'll have got away with it.

Hi,
You are right the 8V has bucket tappets, I finally looked at eLearn.

You should at least check the valve clearances:

Inlet valves clearance in closed position
0.25 - 0.35 mm



Exhaust valves clearance in closed position
0.30 - 0.40 mm

If they are outside this you may need new valves or a SH head.


Robert G8RPI.

Belt, water pump and tensioner changed. Pump breathing was worn and I think it was leaking into the tensioner as it was stiff.

Got the car started up and it is running but rough and a bit of a misfire so I'll get mes plugged in tomorrow and see what it tells me.

There aren't any horrible noises but I know there's something else wrong with it.

I'll post any info from mes tomorrow.

On the assumption that there's a problem with a hydraulic tappet does anyone know if they are difficult to change?

Hi Brian,

I'm not an expert on the 8V but think the engine just has solid tappets with and adjusting shims. Next thing to do if MES shows nothing is a compression test.

Where aare you located? I have a system, Picoscope Automotive, that will do a comparative compression check with just a sensor clamped on the battery lead.


Robert G8RPI.

Brian if you did it yourself, and may be in the open air, I wil take my hat of to you, well done!

Hi Vento, Got it changed outside mostly in the dark and in the rain. Can't get the engine to run properly though so I'm going to need to get the camshaft off and see what's going on.

Hi Robert Thanks for the offer, I'm in Paisley near Glasgow.

Engine definitely not fixed and will need to get the camshaft off to see what's going on.

Do you know whether it's just a matter of undoing the bolts and lifting the camshaft out?

Been away last week so catching up.

If the 8V diesel is similar to the 8V single and twin cam petrol engines then it will be a "true" overhead cam setup. The valves have followers that sit directly on top of the valve stems. Recessed in the top of the followers is a large diameter "shim". The valve clearance is set by using different thickness shims. With the camshaft in situ the removal and replacement of the shims requires two special tools. One to lever the valve follower down and another to lock it in the down position so the shim can be extracted.

Sounds to me that you may have had valve to piston contact on one or more valves. If so then it will be a head off job.

With the head off and valves out apart from visual inspection of valve and piston heads then there are two definitive test you can do.

1) to bench roll each valve stem on a level surface/plate. Any visible head wobble is new valve time. If it looks OK then onto step two.

2) Using a valve lapping tool and past try lapping the valve into the valve seat from which it came. Both the valve seat face and valve head will be ground/polished up. Remove valve and inspect it's and the valve seats polished surfaces. There should be concentric, even and centralised grinding/polishing makes/rings. If not then the valve will require replacing. Some cheap garage jobs will still lap an ever so slightly bent valve back in but this is utmost folly as even if compression can be restored there will be excessive valve guide wear over time. Also there could be hidden fractures in the valve head to stem region that will fail at a later date with the valve head coming completely off the stem doing piston, bore damage and even breaking the engine block.