300tdi Injector pump. Timing pulley end play?

[Glen B]

Hi Guys,

recently had the Disco out for it's first 10 min highway trip after the Diesel install. And the timing belt went south, this after only 100km of traveled distance. No over rev or anything like that, I was still trying to ease her into service, and was in a side street at the time only doing about 30km/h.

Question is, how much play do you expect to find at the injector pump pulley? I'm finding about 1 - 1.5 mm of forward and backwards travel and no side to side action. You can certainly hear a slight clunk when sliding it back and nothing when moving forward. I haven't been able to find any literature on the Bosch VE from a rebuilding and tolerance guidelines point of view. Only assembly diagrams.

I'm wondering if this has lead to early retirement of the belt, and forcing the replacement of some choice new parts. One sacrifice was the crank timing belt drive pulley where the spot welded flange on the forward leading edge has parted from the sprocket. And there are a few others that take time and more patience to get in.

Ideas?

Thanks,
Glen

[ssortnarg]

I checked the ecm version I have in the shop - there is no rotational slack and pulling or pushing the shaft results in a slight movement and a clunk as you have found . I'm no expert but - there is an updated idler wheel , the original had a tendency to cut the edge of the belt . Was the belt tension ,torque to spec ?

[Glen B]

Hi Ross,

thanks for that. Might get me out of an Injector Pump rebuild so early in the diagnosis program. Had to choke when I got the prices back from a reputable company to the tune of $800 - $1000 for a complete rebuild. The parts are only about $50. But the intricacy of the itsy bitsy pieces inside make for a bit of head scratching.

Yes there is an updated crank pulley for the 300tdi after I think around '94 model year, and that has the spot welded shoulders. The updated pulley for the '94 and sooner 300tdi got tensioner pulley with the edge lips instead.

Would be curious to hear if any one has run both the updated pulleys at the same time to try stop the belt walking off into the timing cover.

As for the belt tension, that is where I could have goofed. I used the click style torque meter. Held it at the recommended 11Nm (http://www.difflock.com/servicing/300td ... ndex.shtml) and tightened. Rotated everything rechecked notches and markers, pins back in, all good. I'll most definitely will be getting may hands on one of those needle (deflecting bar) display style torque gauges for the next attempt.

Glen

[discojonny]

Glen,
sorry to hear you are having problems. Does your idler pulleys have the lips on them as well? I remember there are 2 types of idler tensioner puley setups. They are lipped like the crank pulley. I got the wrong ones when I ordered them the first time even with the right part # on the box. Had to reorder to get them right. If the belt walked of the the pulleys that would be my geuss. The tightening of the belt shouldn't be a big deal. as long as you held the 11nm as you tightened the tensioner. also you should tighten, rotate the engine, loosen tensioner and retorque belt and tighten tensioner. this is to get the slack out of both sides of the belt. Give me a call or stop by the shop if you want to talk.

Jonathan

[red90]

As for the belt tension, that is where I could have goofed. I used the click style torque meter. Held it at the recommended 11Nm (http://www.difflock.com/servicing/300td ... ndex.shtml) and tightened. Rotated everything rechecked notches and markers, pins back in, all good. I'll most definitely will be getting may hands on one of those needle (deflecting bar) display style torque gauges for the next attempt

That should still work fine and should not "cause" a failure. Something else must be wrong.

[Glen B]

Thanks guys,

Well the new parts arrived this afternoon :) big yay....
So I'll be in the shop till late monkeying around.

The new improved lower drive pulley is way smarter looking than the thin walled spot welded number that's eaten it's self. Looks more like this one was machined out of a solid piece steel this time.

The tensioner pulley I have, replacement ones also, doesn't have the lips, that's why I was wondering if anyone had stuck both mods from different years on at the same time.

Yeah Jonathan, I'll be knocking on the door real soon.

Glen

[Glen B]

update,

I've heard back from one 300tdi owner who does in fact have 2 pulleys with the edge lips on them. His crank still has the earlier spot welded flanges, and the tensioner has molded guides along the outer edges.

So it' do able. He's only got about 4500km since the belt was done last and no problems at all.

[red90]

Very carefully check that all pulleys are in line and parallel.

[Glen B]

Thanks Red90,

Timing belt seemed to be riding closer to the front on the IP pulley than the cam shaft pulley. So I've shimmed the back of the timing cover and the face of the IP on the outer most of 3 bolts that secure it to that cover. Just a washers worth. About 1.5mm thick. If this is the sweet spot I'm going to have to make a plan about sealing up the gap to keep crud out.

Done 150km so far and get to take timing cover off again tonight and have a look at the tell tales if she's happy or not.

Something else that was bugging the heck out of me was the terrible squeal on the tensioner pulley for the ancillaries. I had redone the bearing 2 days ago, but that was just as bad. Last night through a complete goof move on my part the belt snapped while driving.

So having ordered a few new spares put one of those on. Well... it's a ..1595 and the old one ( 2 weeks old) was a ..1580. We matched that one against the original and figured hey it must be right. This newest slightly longer belt seems to have cured the dreaded canary under the hood syndrome.


Glen

[Glen B]

So this is what it looked like after 170km this evening:

IP pulley, riding on the outer edge.
http://sphotos.ak.fbcdn.net/hphotos-ak- ... 1944_n.jpg

Cam pulley, black marks in the grooves look like it's traveling under load.
http://sphotos.ak.fbcdn.net/hphotos-ak- ... 3227_n.jpg

Tensioner and Idler both on their outer edges.
http://sphotos.ak.fbcdn.net/hphotos-ak- ... 1091_n.jpg


http://sphotos.ak.fbcdn.net/hphotos-ak- ... 2332_n.jpg
http://sphotos.ak.fbcdn.net/hphotos-ak- ... 3306_n.jpg

No dust or burnt belt
http://sphotos.ak.fbcdn.net/hphotos-ak- ... 3977_n.jpg

Looks like I'll let 'er be for a few more km till she hits 500 or the first oil change.