Jump to content
  • Welcome to 205GTIDrivers.com!

    Hello dear visitor! Feel free to browse but we invite you to register completely free of charge in order to enjoy the full functionality of the website.

Sign in to follow this  
Elad

What Timing Belt? (saxo 1.4 1998)

Recommended Posts

Elad

Hi,

the car is a 1999 Citroen Saxo 1.4

the engine is TU3JP (1360cc 75HP)

 

there are two options:

108 teeth, DAYCO 94256 (I have this one but it seems that the timing locks do not align using it)

104 teeth, DAYCO 94862

 

BTW - should the timing locks (camshaft sprocket and flywheel) lock exactly together with the timing belt on and correctly tensioned?

 

which is the correct one?

thanks,

Elad.

Share this post


Link to post
Share on other sites
Sandy

If it's a 42 tooth cam pulley, it's 108, if it's 38 tooth, it's 104. If the cam pulley dowel (about 2 o'clock as you look at it) and crank dowel locate, the belt should fit fine. If the tensioner tries to go over centre, the head might have been skimmed before, too much.

Share this post


Link to post
Share on other sites
ajm-e30

have the chassis number ready when you order or the engine number which you have

Share this post


Link to post
Share on other sites
ajm-e30

iv never used a locking tool to do the belt on one of these as they are very straight forward, all you need is tipex to mark tdc on the crank and cam

Share this post


Link to post
Share on other sites
Elad

Hi,

thanks for the helpfull answers - sandy309 I think you'r onto something,

the head had been skeemed twice (but just the minimum - about 1mm im total),

the tensioner doesn't try to go over the center.

 

the locking dowels can't be inserted simultaneously using the 108 toothed belt (if I lock the flywheel first then the cam pully will be about half a belt tooth to the direction of 1:30, instead of 2 oclock),

I've put the belt as it is (this is the second time I replaced it having driven 70,000 km with this setup in total) but the car (from the day we bought it) always felt weak and slow in comparison to other (four) Citroen Saxo (1.4 petrol) we have in the family, I suspect it has to do with that timing retarding (I've checked everything else...)

 

what would retarding the cam pully by half a tooth do to the beheviour of the engine?

do the locking dowels indicate the best timing setup?

 

what is the solution? CatCams? :P

regards,

Elad.

Edited by Elad

Share this post


Link to post
Share on other sites
Sandy

Half a tooth is equivalent to retarding the cam about 4 degrees, which would certainly make it feel lethargic! The only way to make it work properly is to restore the head height with a thicker gasket (oversize is +0.2mm). If the head height is less than 111.0mm face to face, then you'll not be able to restore normal running without re-mapping the ECU, or changing the head for a suitable one. Using an adjustable pulley to restore the cam timing would be complex, expensive and the compression would still be an issue. Changing the cam gets you into re-mapping again and rarely gives any genuine benefit on the standard TU 8v without inlet changes.

Edited by sandy309

Share this post


Link to post
Share on other sites
Elad

Hi,

Just measured the cylinder head hight, it's - 111.27mm

I thought it would be less... the cylinder head was overhauled twice...

now i'm really puzzled... :P

why is the misalignment in the timing dowel locks?

:ph34r:

any ideas would be great...

Elad.

Share this post


Link to post
Share on other sites
Elad

counted the cam teeth - 42 teeth

Share this post


Link to post
Share on other sites
Sandy

Hmm, sorry, can't really help you any more than that without seeing it.

Share this post


Link to post
Share on other sites
Elad

what's left to do is compare the cylinder head hight and the timing dowels's positions on a "good" Saxo,

i've allready asked for quotes for a vernier pulley...

regrads,

Elad.

Share this post


Link to post
Share on other sites
Elad

another thought (I can't let go and wait until the weekend...)

since the camshaft lobes (press and let go of the valves) have an oval finish (at the pressing tip, and the at the other 80% of the cycle have no contact with the valve = the valve is closed) it occurred to me that the influence of the "half tooth (~3deg) retarding in the timing belt" is neglectable (valves position relative to the piston position wise) but the more important issue is injection and ignition which precede the valves (by the mentioned ~3deg).

is there a way to retard (by programing for example) the ignition / injection through the ECU (Magnetti Marelli 1AP)?

do you think my theory is logical?

Marry Christmas!!!

Elad.

Share this post


Link to post
Share on other sites
Elad

Just had to get in truble... :(

first thing I noticed is that I tensioned the timing belt pulley the wrong way (I tensioned it clock wise instead of anti clock wise - looking from the right side of the car).

I fixed that, and now the dowel locks align perfectly,

problem is I started the car and it worked badly,

I took the timing belt off and started again and found out it was located a tooth off,

I fixed it and during that I found out that the flywheel has two lock positions, 180deg apart in the camshaft (probably becase the crankshaft sprocket has 1/2 the teeth the the crankshaft completes two turns while the camshaft only completes half a turn).

how do I know what's the right crankshaft location relative to the camshaft? (there are two options - 180deg apart in the crankshaft)

I took out the plug in cylinder 1 (next to the gearbox) to see the cylinder location (up or down) because haynes says that the crankshaft lock should lock the camshaft at the compression TCD - I can't figure it out from looking at the cylinder...

now the situation is that the car does'nt start...

how do I set the correct zero?

Help!!! :o

Elad.

Share this post


Link to post
Share on other sites
Sandy

There is only one notch in the flywheel for the crank dowel, but it'll pass twice for one revolution of the cam,because the cam is geared at half crank speed. When the dowel is correctly located in the flywheel, cylinders 1 and 4 will be at TDC. You can check for this by taking the plugs out and rotating the crank with a screwdriver in 1 or 4 plug hole to feel the piston position as it moves you must take care to keep the screwdriver "loose" though, or it may get trapped near TDC as the piston rises! If you're rotating the crank with the cambelt off, you must pay due care to the angle of the camshaft, because some of the valves will be open!! Best bet is to have the crank somewhere around 90 degrees after TDC, rotate the cam to the locked position, then bring the crank back 90 degrees to TDC, in that order.

Share this post


Link to post
Share on other sites
Elad

what I understand is that at the crankshaft lock - cylinders 1 and 4 should be at the top of their stroke = TDC ?

I'll do it with the timing belt as I'm hopeing to be missing just a tooth...

otherwise I geuss I had already bent some valves... :o

though I hope It's not the case since I locked both the crankshaft and the camshaft before taking the belt off and replacing the water pump.

Edited by Elad

Share this post


Link to post
Share on other sites
Elad

dear sandy309,

more news...

I locked the crankshaft through the wrong hole :o

there is a hole for a pickup sensor covered with a plastic cap and next to it is I guess the hole for the bolt meant to hold it - this is the hole I locked the flywheel with... :(

there is a hole closer to the cylinder block that by using to find the lock position through, brings cylinder 1 to the TDC (BTW does it stand for Top Dead Corner?) so I guess this is the right hole...

locking the crankshaft at this point (with the belt on) shows that the camshaft is about 5 teeth over the camshaft lock position (about 42.86 deg earlier then the crankshaft).

should I expect valve damage?

do you think I can (with the crankshaft locked) turn the camshaft 5 teeth back?

Elad.

Share this post


Link to post
Share on other sites
Elad

sad news...

bent valves :o:(:lol:

Elad.

Share this post


Link to post
Share on other sites
Sandy

Bugger, I'm sorry to hear that. It's always difficult to copver all angles, advising this way :)

 

It's an easy head to rebuild, looking at the positive.

Share this post


Link to post
Share on other sites
Elad

Hi again,

a friend from work said somthing interesting,

he said modern engines are designed to be undamaged even if the timing belt snaps,

the logic behind this is the following:

the compression ratio is ~1:10 so for a stroke of 77mm there is a gap at the TDC of around 8mm (or more with the burning chamber's dome),

the valves open just a slight bit when they do,

any chance for no damage?

the engine isn't round and smooth so I think I did bend a valve or more... but it might just be the plug I took out that isn't closed well or went bad...

what do you think?

Elad.

Share this post


Link to post
Share on other sites
Sandy

I don't know how he worked that out, but the maximum lift at TDC before interference on the late 1.4 TU is about 2.5mm, all TU engines are "interference" sadly. But it's always worth timing it up properly and seeing if it runs ok.

Edited by sandy309

Share this post


Link to post
Share on other sites
Elad

more luck then brains...

car is back to normal :)

Elad.

Share this post


Link to post
Share on other sites
Sandy

Good stuff, what did you have to do in the end?

Share this post


Link to post
Share on other sites
Sign in to follow this  

×