2.4 JTD "loose chain" noise when hot?

Evening all,

Now the hot weather is here my car is developing an annoying noise when hot (80+)

The noise is not present from cold but appears as the engine warms.

Its sounds like a loose chain driving a sprocket or poorly adjusted tappets. It comes from the cambelt end of the engine and it's loud enough to be heard over the regular diesel drone.

It's most noticible at idle upto 2000rpm and worse when not under load.

I think I read somewhere that it could be the oil pump but I can't find the post.

Any ideas?

could it be the auxilury belt tensioner ??

I had a similar problem on my Fiat Marea 2.4TD engine (same 5 cylinder engine but predecessor to the JTD version) a few years ago. Firstly, the rubber bush in the crank pulley started to break up so replaced the pulley (DIY) and noise gone (also dismantled the spring loaded aux belt tensioner, rotated the spring through 180 degrees about its axis and then greased it). About 9 months later, a horrible rattly chain noise appeared, similar to what you're describing above. Had a new oil pump fitted and problem solved. Unfortunately, it was a garage job (7hrs!!) because I couldn't remove the bolt from the crank - left hand thread and bl00dy tight. If you have access to a windy gun and a pit you might manage it yourself, but the exhaust and sump have to be removed first.
The timing belt needs to be removed when replacing the pump so you may as well have the belt and tensioners replaced at the same time.
Hope this helps and good luck.

Bugger.

Just had my cam belt, aux belt and tensioner changed !

I'm sure a read somewhere that the noise is just the way these engines sound when hot.

I'll explore the rubber crank pulley and report back.

Meanwhile - anyone shed any light on whether this noise is normal?

I reckon the valve clearances might need shimming. But, I did 30K in my JTD and never did this job, and it always sounded tappety at idle, never got any worse either between 90k and 120k

Originally Posted by Pud237

I reckon the valve clearances might need shimming. But, I did 30K in my JTD and never did this job, and it always sounded tappety at idle, never got any worse either between 90k and 120k

Is this a big job? I was planning on having them checked at my next service in 4k

Yes it is a big joblike almost every engine job it's belt off again.

Originally Posted by Smaky

Yes it is a big joblike almost every engine job it's belt off again.

You don't need the cam out to change the shims.
You just use a tool to depress the bucket.

They are scheduled for checking every 12000miles/12-months. If it meant cambelt off it would be a very expensive yearly service...!

Originally Posted by David C

They are scheduled for checking every 12000miles/12-months. If it meant cambelt off it would be a very expensive yearly service...!

I know I've said this before and you disagreed with me but my Alfa mechanic of 15 yrs reckons they need doing once at the 24k service when two years old, and then the chances of you ever needing to do them again are very low.

Originally Posted by Pud237

I know I've said this before and you disagreed with me but my Alfa mechanic of 15 yrs reckons they need doing once at the 24k service when two years old, and then the chances of you ever needing to do them again are very low.

I've just checked the schedule.
They are scheduled for checking at 12000miles, 24000miles, then every 24000miles after that.

But it is a simple procedure to check them anyway, just remove the camcover and check with a feeler gauge.

Originally Posted by David C

I've just checked the schedule.
They are scheduled for checking at 12000miles, 24000miles, then every 24000miles after that.

But it is a simple procedure to check them anyway, just remove the camcover and check with a feeler gauge.

Thanks David C,
I will check this myself prior to the next service.

However, as a man who seems to have the right answers - what are your thoughts on my initial question - Could this noise be the norm for an early 2.4 jtd oil pump or is it more likely to be the shims?

2.4 JTD "loose chain" noise when hot?
Hi there Ricer, my 2.4(136) sounds as though it has the same problem, checked tappets all ok, checked bottom pully ok, car has done 146,000

UPDATE!

I had a good look and listen to the problem today. First thing i noticed is that my undertray has gone! Don't know how or where, but it isn't there. There is no damage to the sump or any components.

The noise is not from the top of the engine. It 100% comes from the sump, and possibly from the front of it, but I could be imagining the last bit. It is not present from cold and only appears from warm to hot.

Strangely, it gets slightly worse under minor load - aircon, power steering etc, however, it is not a noise which comes from the aux belt.

Oil pump or big end problem . . . . ?

im going to take mine apart this week and check it out.

Have a similar noise myself,(2.4jtd.) before this happened the the main aux pulley went, the rubber disintegrated so it was changed along with te diesal pump which blew the seals unrelated I know but was producing a hell of a diesal knock.
Since then the aux belt has been removed and replaced because the gear box has been dropped yet againfor the clutch issue I am having, so I think an extra strain has been put on the aux belt drive chain, as in belt, because its dismantled to allow the engine to tilt.
The aux belt and tensioner pulleys were replaced last year with genuine alfa parts , so surely this is not at fault?
I suspect either the alternator bearing or the aircon bearing to be next , but not fully investigated yet

I had a similar issue after I had my cambelt changed at 72k by an alleged "Alfa/Fiat Specialist" garage in Stockton. After the service and belt change I parted with my cash (about £600 ) and took the car. I noticed the rattle you describe later that day and took it back the next day. They then told me it was the auxillary belt tensioner and said it could be fixed for £300!!
Why they hadn't noticed this when they did the cambelt I am not sure but for them to have to take the car for another day, me losing another days holiday and then being charged £300 was slightly annoying. Would have been a great deal cheaper if done altogether.
I do know that the noise wasn't there when it went in for the cambelt change but was when it came out!

Mine is not the tensioner - I had it replaced about 1 month ago.

The noise is coming from the front of the sump. I'm almost sure it's the oil pump as they are chain driven and apparently noisy on these old 136bhp motors.

I'd still like a little confirmation though . . . . .

Hi guys, just waking this thread up again, what was the result of all the checks? I too am hearing this noise being described and am becoming increasingly worried that something is going to let go before I get a chance to rectify it. Should I be worried about the noise and if it is the oil pump, does anyone know of a removal/replacement how-to? I need to change the cam belt and have bought the bits already for that job. If the pump is in need of replacement, I would like to know if this is something that should be done at the same time.

Any info, links to guides etc are of course very much welcome.

Regards