Alfa 159 1.9 JTDm Timing Belt

[Prizam]

Last week, I went to start the car, and it sounded like a bag of crap. So turned it off. I did a quick visual, and everything seemed ok. No EML light.

So, started it again. It struggled to start, and when it caught it sounded like a bag of crap again. Foot to the flor in neutral and wouldn't rev past 2k rpm.

I took the wife's car to work...

When I got home, I plugged the computer into it and found a code for the cam position sensor. I got a visual on the cambelt and it was loose, movement between the fuel pump and camshaft of over an inch.


Today I have been doing the belt, water pump and tensioners. The original tensioner had shat its pants.


I marked up the cam when the bottom crank was at TDC. (Via its TDC markings)

When I replace the belt and use the line markings on it, I'm about 4 teeth out on the timing from where I had it marked up.


Do I go with the markings that I made, or the markings on the timing belt? 4 teeth seem like a lot.

(I don't have any specialist timing tools.)

[Chris32345]

Givenw how it's already likely been thrown out of timing your best getting or lending some timing tools to make sure it's back together right

[Auntieroll]

You should be able to find a tutorial on line explaining how to do the job.
AFAIR there are 2 different cambelts ,only 1 tooth difference between them.
You will more than likely have broken some rocker followers , these are a rather useful weak link which tend to break when the pistons clout the ( fortunately vertical ) valves .
Most times the valves escape with no damage , but the multitude of tiny needle rollers which are released take an age to find and clean out though.
A timing kit is not essential as only the cam and crank need to be synchronised , the HP pump is not timed as it only pressurises the rail.
Have fun getting the injectors out and the new belt on !
HTH

[Prizam]

Thanks. If it needs anything more than a new belt then its getting scrapped.

It was running and sounded like it was on all 4 too. So im hopefull nothing has broken.

The question is... Do i use my own markings. Or the ones on the belt to time up the pullys.

[Matt_E_Mulsion]

If I understand you right you've marked it up from where you took the old belt off. This was not necessarily in the right place because it may well have jumped a few teeth, hence why the car ran very badly. I'd time it up using the proper timing marks.

[Prizam]

Yep. Thats correct.

Though timing markings is somthing this engine seems to lack.

The belt markings do time up with markings some one else has made.

[227bhp]

Read a workshop manual and do it properly instead of dicking around and asking daft questions.

[Prizam]

227bhp said:

Read a workshop manual and do it properly instead of dicking around and asking daft questions.

You colossal tt. RTFM isn't going to solve this very specific question. If you cant contribute anything helpful then don't add anything at all. It's clear you don't have a clue, so shut up and let the big boys talk.

[Prizam]

Quick update for you, in short. I ignored all other timing marks and went with the belt. I figured that the timing had to be off, but not by 4 teeth!


The first pass on timing was as the picture below. My original mark was the black line to the right of the bolt hole. As it is timed. The cambelt mark lined up with the black line to the left of the hole. (Someone else mark). Timing looks to be about 10-15 degrees off, but the engine was running before I took it apart.




I then moved the crank by hand to line up with the belt and the previous markings, keeping the bottom pully at what I am assuming is/was TDC.




I then timed up the fuel pump, it apparently doesn't matter, but I had a marking on the belt for it so... why not. Since I'm putting all my faith in the new belt.





The bottom stayed at TDC the whole time. At least, I think its TDC. its the only marking I can line up on any sprockets.





The aux belt was shot. cracked and had missing valleys, so I didn't want to put it back on.

After turning a few times by hand, it was cleaning all valves, so replaced the glow plugs and the engine mount.

I started it up, and it ran... but sounded like a bag of crap. very rough idle and occasional clatter/bang. So stopped it quick.

A little further investigation and it seems like the AUX tensioner when it has no load on it, just touches the crank pulley. So re-instaled the aux belt, lifting the tensioner away from the pulley. my thought process being that the extra load on the engine might be used to smooth out the idling.

I started it up again, and whilst it wasn't banging about. it still ran like a pig. Very lumpy with very little power. Assuming the worst, that it had valve damage. With nothing to lose, I gave it a boot full.

It coughed and sputtered, but the revs began to rise and then woosh... a cloud of black smoke shot out of the exhaust and it began to run properly. No damage.


My theory is...

a) It had air in the pump and wasn't getting the correct fuel pressure.
b) the cam sensor error it had before, took a few revolutions to clear and bring its self back in to sync.


Either way, it seels to be running well again, and disaster has been averted. JUST. I can't believe that the timing was so far out and didn't break anything.

I found the remnants of the cambelt tensioner in the undertray. half a spring and a few metal shavings.


Thanks to those of you who made helpfull comments.

[bungz]

Well done, a close call.

Simple enough and looks like it was a good guess.

http://www.forum.alfaholicy.org/images/imported/20...

[Retep1234]

hello, I have a boat with Vetus engine, the base is a 1.9 JTD 140HP. Fiat. Diesel. I want to replace the timing belt but can't find the mark on the block. Who can indicate the correct mark?