Alfa Romeo Forum banner

2.4 Ti Engine PRoblem

1K views 8 replies 6 participants last post by  woody10381 
#1 ·
Hi all,

Long time lurker, first time poster! I'm the proud owner of a 2.4 JTDm TI (sans DPF & EGR) and have had 2 years of relatively hassle free motoring.

That has somewhat changed today, ironically on the way home from the MOT centre with a pass and zero advisories...... All started well however a few miles and away from the dual carriageway, I noticed that the engine note had changed to resemble a clattering akin to the most coarse of tractor engines.

Pulled over to have a look under the bonnet, to see the engine vibrating far in excess of usual. Turned around to head back to the garage - power was way down, very sluggish at low revs with the turbo very slow to spool up. Normal driving speeds were achievable, the clattering almost dissipated once the revs had picked up.

Got to the garage for an initial look, although once the engine was stopped - it refused to start again and is now stranded on the forecourt.

The suspicion is that the timing belt has jumped, although the belt still appeared to be tight upon first look. The chaps at the garage now have it and will be carrying out investigations tomorrow.

The car has 90K on it, the timing belt (with water pump mod) was replaced at 73k about two years ago. Does anyone have any experience of something similar or thoughts as to what might be going on? Any advice will be greatly appreciated!

Fingers crossed that there isnt a huge bill coming my way.......although at least I've got a full MOT.......

Thanks

Woody
 
See less See more
#5 ·
Thought I'd update this for those who may be interested.........

The cause of the problem has been traced back to a failure of one of the lugs attached to the tensioner, which has allowed the tensioner itself to "retract" too far back - thus resulting in the timing belt slackening off and jumping four teeth. (I'd be interested if anyone here has experienced anything similar....??).

Luckily, there doesn't seem to be any obvious damage to any of the pistons, valves or rockers - as the engine is now running again (after being re-timed and fitted with new timing belt & tensioner kit), with all 5 cylinders delivering full compression. However; I've been advised that I cannot be 100% sure that there has been no impact damage to any of the engine components without removing the engine top cover and inspecting the valves close up.

The dilemma I'm facing now is whether I should either retrieve the car and continue driving it, or make doubly sure that there has been no impact damage to any of the components (i.e. hairline cracks, deformities, etc) - which will add approx £500 to the bill.

I'm swaying towards accepting the current state of the car, based on the fact that all cylinders are performing to spec - which would not be evident if there was damage to the valves? Is it possible to "get lucky" with this type of failure or is there likely to be a residual impact which will hit me in the not-too-distant future?!

Has anyone got some advice, or suggestions as to what I should look at / discuss with the garage before I make up my mind?

Cheers

Woody
 
#9 ·
No, absolutely certain. They would not have been anywhere near that part of engine during the MOT. Plus I have the old tensioner and timing belt on my desk, and can see for myself where one of the metal lugs on the tensioner has sheared. The witness marks on the belt also identify where it has jumped.

Plus they could have lead me down the path of inspecting each of the 20 valves and rockers, instead I was given enough information to make my own decision.

It's hard to identify a root cause to this type of failure, I can only assume that there was some form of defect in one of the tensioner components prior to fitting. Maybe I was just unlucky!

Thanks to everyone who offered advice, I'll update this thread if anything develops in the future.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top