Hi,
having found useful stuff on here to help me fix my non running heater fan I have been searching for info regarding another problem. No luck so far so thought I'd ask the direct question and see what others know.

It started a year ago when the Doblo failed its MOT on emissions. I was advised to add a fuel system cleaner and run it at high revs ( I normally run low revs and high gears - using the ample torque. I did this and it dropped the emissions from 7% to 0.7% for a pass.

However, after that there was a rattly noise in the engine a bit like a wide (manually adjusted) tappet. Since these are hydraulic tappets it can't be that and anyway why would one suddenly change? The noise has remain fairly consistent since then being engine speed related and generally unaffected by engine temperature.

In the year since it has had no end of things tried including:
further system cleaners
oil changes
bottom pulley change
timing belt change (due anyway @50k miles)
oil additive
injectors rebuilt (£600!)
and all to no avail as the noise is still much the same.

In this period the indicated fuel consumption has remained good, slightly increasing if anything to an long term average of 60mpg. Only recently has there been an indication of a minor reduction in power.

From threads on here I am wondering whether it is worth inspecting the EGR valve for clogging. I have already confirmed that fuse F11 is OK (other fuel injection functions?).

Does anyone have any suggestions of cause or remedy? I am beginning to think that I might have to remove the camshaft to check the tappets and then the head to check on the valves themselves.

All help welcomed.
thanks
dgary

dgary said:

However, after that there was a rattly noise in the engine a bit like a wide (manually adjusted) tappet. Since these are hydraulic tappets it can't be that

Click to expand...

The 2003 JTD 8v engine has replaceable shims to adjust the valve clearances. I believe it wasn't til the 2004 MJTD 16v that hydraulic adjusters appeared.

Dave.

Thanks Davren,
you have just reopened a can of worms I thought I had got firmly lidded. Fiat (dealer & UK) keep telling me that they are hydrualic on my vehicle whereas a local engine rebuilder says they're shimmed. Interestingly, the parts system at the dealers seems to list a whole load of shims. Are these needed to pre-set the hydraulic tappets?

Looking back at my original post, perhaps I should expand a bit on the 'high revs' use. I think I was using around 4,000 rpm or perhaps a bit more by running second gear up around 50mph or so. This is unknown territory for me since it rarely sees 3,000 rpm in normal driving. Given that there is no red line on the rev counter - is there a recommended max revs?

I suppose that what I am looking for is either confirmation or disagreement that the high revs, together with loosening coke from the engine generally, could have caused a problem in a tappet or perhaps have broken a valve spring or something. Has anyone had anything like this happen?

dgary

You are assured that the engine knocks? The reason can be in
Tension roller of a belt the generator.

hab said:

You are assured that the engine knocks? The reason can be in
Tension roller of a belt the generator.

Click to expand...

+ one

Mine's the same year and engine and it is a bit tappety, and it has been for years - if I can remember that far back; but I live with it. Is there something wrong then? I often cruise at over 3000, but have never got to 4000

Auxiliary and cambelt changes, but apart from that: nothing. Should I worry?

I read about Valvoline oil in a thread by Niall. I had it put in a couple of months ago. I was astounded at the difference. Everything is quiet and torq has increased. Almost sounds like a petrol car lol. 20 quid for 5 litres. I wont be using anything else now.
Mind the car was going good anyway. It must be driven hard I find. Its not a town car at all.