cam timing

[mechuccio]

Hi There,

I'm replacing my timing belt, but I've got this problem with it.
I'm, using the Haynes, and I've replaced timing belts before (this is my first 16V engine though) anyway, I could lock the crankshaft, and I could lock the inlet cam, but the outlet cam can't be locked It seems as if the timing of the outlet cam is of, I can twist it so the holes correspond, but since it was running very smoothly I'm not sure what to do now.
When running stationairy on normal fuel the engine runs fine, but the exhaust makes a stuttering sound, it does not do that while running on autogas.

What's your opinion? should I just time the cams according to Haynes? or build everythinh back as it was? the waterpump and tensioners are replaced already, now comes replacing the belt and timing it.

I'm a bit unsure about is......

Anybody got the winning answer?

[jayw]

That seems VERY odd, as IIRC timing is adjusted via the tensioners?

Although i equally have never changed a belt on these engines yet (I am due to do it soon though).

--EDIT--

I've just flicked through the Haynes (the good old (brown) version), there should be absolutely no problem with locking any of them.

I assume you are aware the exhaust pin locks through the Southern point (bottom) of the pulley and the Inlet locks through the western point (left) of the pulley?

All looks relatively straightforward with the exception of accurate tensioning.

I DEFINITELY WOULDN'T ATTEMPT RUNNING THE ENGINE WITHOUT HAVING THEM CORRECT!!!

Alternatively it's possible you've got non-standard cams, but i'm pretty sure the profiles are only slightly adjusted so wouldn't make any difference to pulley alignment.

[Toddman]

IF your engine is pretty much standard and had not been tuned and had the cam timing optimised then I would strongly suggest locking the pullys as per Haynes and doing it correctly.

There is a some room for varying the cam timing but it is usually the inlet cam that is adjusted as this affects the torque quite a bit.

Use the correct locking pins, NOTE: The haynes drawing is wrong the short length should be the smaller diameter that fits into the head.

So in short set it up as it should be.

Cheers
Luke

[mechuccio]

Heyz

My father and I worked on it for a bit longer, indeed we just took off the timing belt, twisted the outletvalvecam, locked both of them, replaced the belt, and \did everyting according to Haynes..... what do you think?

It started *much* faster, normally the engine has to go round 7 or 8 times (not whith a warm engine while starting on autogas) and the plopping sound from the exhaust system is gone....
It seems that for at least 2 years the cam was wrongly timed (2 teeth on the belt)

But now she works!!

Thanks for the advices!
I'm going to finish the job now, and see if she's faster now

[jayw]

If that's the case then it does beg the curious question as to how you were running 158bhp?

[mechuccio]

It was quit a strange situation indeed....

Both my father and I were stunned to see that the holes didn't align for the outlet cam sprocket. We've checked it several times, and the only conclusion we could make was that the last time the belt was replaced someone screwed up!!
The engine on the other hand was running just perfectly fine! ofcourse the fuel inlet was good. Just the starting and stationairry run (never really had problems with that) are better now.

Usually when starting cold, the engine ROARED when coming to live now it sounds like a nice decent car when starting.

Ofcourse I haven't tested the power yet, first I have to travel a couple of 100 kilometers to be sure of the new belt, but I have to say that with the old belt it was quite fast 'nough beamers annoyed already

[AlanS]

According to a guy over here who is an engineer and does cannibal conversions, the sprockets have a number stamped on them (2 - 3 or 4 as you may have noticed) and if there are a few available, it's possible to rearrang the valve timing slightly by doing a mix and match.
I think it's 2 intake and 3 exhaust he claims is the best combination.
He also makes up and sell intake cam sprockets with a 3 degree offset which they also reckon gives a slight extra power increase, but in all cases, the position of the locating pin remains the same.
I recently made a clamp to lock the actual cam sprockets when I did a cambelt on a Xsara VTS which I also reckon could be used on a 16V when doing the cambelt in conjunction with the pins but as yet haven't tried it ion mine. However, I would reckon anyone using this style of clamp who didn't also use the pins, could quite easily set the belt on a wrong tooth just as some have done when trying to fit the belt between the camsprockets when the clamp isn't used.


Alan S

[ollie]

Can't suggest any wisdom on the cam thing apart from trying it, I was allways under the impression that the 16v was fussy on timing.

But, AUTOGAS on a 16v tell us more did you do this yourself and if so what system, and how does it run? is full power affected?

I do gas kits myself but wondered if they worked OK on the more highly tuned engines, especially the ignition timing, as the burn characteristics at high speed would be very different, and the 16v doesn't self map new ones like most of the newer low powered stuff. does it run hotter on gas? or do you just use it for steady speed cruising?

Ollie

[mechuccio]

My BX runs very good on autogas, I did not install it myself, it was done when the car got imported into Hollan (09-2000)
Its a standard (g2) installation, so just a hose connected from the vaporizer to the airhose. The only thing which was new for me on this installation is this "pitagora pi-generator" this is connected to the injectors and shuts them off when driving on autogas.
About the performance. thats very ok, still much faster then most cars, but there is a *BIG* difference, for instance the max rpm I reach on gas is 5100 no more, and its a bit slower on acceleration.
The engine never runs hot or anything, and a fifteen hour drive with 4 people to Hungary was no problem at all.
As I understood this engine (because of high compression) is perfectly suitable for an autogas installation (so I have noticed)

[Anonymous]

having a pair of these made may help you with any cam timing issues



http://www.aussiefrogs.com/forum/attach ... 1154435720

diagrams of cam locking tools obviously you would need 2 one for each cam

and then there is also a locking pin that will go in bottom pulley but i cant find a diagram for that i always use an apropriate size allen key but maybe someone on here will have a diagram of that also

[Vanny]

that diagram is wrong! The length for the smaller diameter should be 10mm and the bigger diameter length should be longer so you can actually get the pin out of the hole (more like 35mm).

NEVER TRUST A HAYNES MANUAL EXPLICITLY!!

[Timmo]

whitty, there was a group deal that one of our members got a mate in a amchine shop to make up a load of sets of pins for all those that wanted not long back! i have a set here! the crank pully can be locked with soem threaded bar but i cant remeber the diameter! lol! i have a long ratially threaded bolt thats fits spot on that i painted the ends red on to make it stand out a bit more!

[Vanny]

the crank pully can be locked with soem threaded bar but i cant remeber the diameter!

10mm (correct me if im wrong, it happens ) most timing pins for psa engines are 10 mm especially XU derivatives (which the 16v is)

[Timmo]

thanks vanny! i had 8mm in my head for some reason! and if honest, couldnt be bothered to go out to the shed and meausre the one i have hahah!

[Anonymous]

strang you say that diagram is wrong cos thats what i had made up, admitadly i did make them longer so i could drill through the end and attach a big red square of plastic so i couldn't forget them but they worked a treat but mines an xu10j4 not an xu9 are they different?