Tensioner - how stuff works

#1
Discussions in the "z20net tensioner for z22se engines" topic of this forum show that there would be a need to know how both tensioners work in order to be able to judge which one is better.
Let me present here my attempt to make such a z22se tensioner description.
I am promised by vocky to receive a photo of the z20net dismantled tensioner internal parts and then it could be possible to make an attempt to work out the z20net functional description, too.

aimg545.imageshack.us_img545_4695_tensstretch.jpg



1 tensioner body, 2 and 3 sealing ring, 4 piston, 6 segment with shaped slot, 7 pin

An oil pressure generates the power that works at the tensioner output pin. The oil enters the tensioner body via an opening in it and this opening is situated in a passage between both sealing rings.
The adaptation of the tensioner adjustment in dependence on the successive prolongation of the chain within its lifetime is ensured by the segment inserted into the piston (item 6 - its "unwrapped" view is shown in the right-top picture). To this purpose, the segment is equipped by the longitudinal and sloping shape as shown in the right-top picture.
The shaped slot is faced by a small protruding pin (SPP) inside the piston.
The spring with its terminating pins generate a power pushing the piston out of the tensioner body. In addition, the bigger pin closes the piston small frontal opening (as shown in the right-bottom picture) and this way the oil inside the tensioner would be sometime able to leak back to the engine space.
The selected segment hollow C (4 of them) limits the piston from returning back into the tensioner body when subjected to the tensioned chain power arising after the oil pressure is cancelled (engine idle state).

Tensioner initialisation - out of the engine (left-bottom picture)
Fasten the piston 4 into a vice as shown in the picture.
Insert the segment 6 with the spring and its terminating pins into the piston. Then push the piston inwards by simultaneous turning it clockwise so that the piston pin passes entire shaped slot and finally locks into the B hollow.

Tensioner intialisation - after installing it into the engine
Push onto the chain with its guide and this way onto the tensioner piston so that its pin leaves the segment B hollow. Then it is guided via the section D of the shaped slot so off as it is allowed by the actual chain length and then it keeps its position against some of the C hollows.

When the tensioned chain is pushing back to the tensioner piston, its return is limited since the piston pin snaps into a selected C hollow.

Any comments to this description are welcome.
 
#2
SAM_1238.JPG
some of the internals appear to be shared between the two types of tensioner - z22se and z20net :confused:

the z20net requires much more effort to compress than the z22se when tested on the bench (y)

note the two types of body for the later spec z22se tensioners, one has an extra seal (green)

click on the pic to get the full image
 
Last edited:
#4
Many thanks to vocky for the picture.

A question to it:
Is the Z20NET tensioner body equipped with the oil input opening (similarly as by Z22SE type - approx. 2 mm opening) in its narrowed section next to the threaded part ?

Based on this info, it would be possible to judge if Z20NET tensioner rely on oil pressure at all.
 
#5
if you look closely at the z20net tensioner you can see a cutout in the threads, there is a hole for the oil pressure there (y)

the z20net uses the same spring as the z22se but it has more tension - probably because the area where the spring sits has less room
 
#6
Let me present here the following information collected from web concerning the Z20NET tensioner and its initialization.

this topic here (vocky):
some of the internals appear to be shared between the two types of tensioner - z22se and z20net
the z20net requires much more effort to compress than the z22se when tested on the bench
the z20net uses the same spring as the z22se but it has more tension - probably because the area where the spring sits has less room.

http://www.ecotecforum.com/forums/showthread.php?13604-Timing-Chain-Tensioner (Cavillac)
this tensioner is the same design as the original, cept its "guts" are held in the bore with a snap ring. to reset it, u have to remove the snap ring, and reset it just like the original tensioner. when i took mine apart when i had a valve spring break, i had no idea how to reset this unit, i just took it apart and discovered it was the same as the old one.

http://www.ecotecforum.com/forums/showthread.php?14849-Timing-chain-tensioners (AYl redline)
you have to compress it before install, then once it is screwed into the head and in place, you have to hit it with something through the access under the valve cover, once you hit it it will expand and tension the chain.

http://www.ecotecforum.com/forums/showthread.php?13604-Timing-Chain-Tensioner/page2 (mike)
when i changed out just the timing tensioner on one of these engines ... i installed the new one which was a new style tensioner ... i could physically see the v-groove line up with the ridge in the tensioner guide.

From these, the advice "remove the snap ring, and reset it just like the original tensioner" seems to be quite reasonable.


However, my attempt to confirm such a Z20NET tensioner related information directly from Opel head office in Rüsselsheim am Main Germany failed, regardless the Opel directive (Opel 2366 Feldabhilfe) on Z20NET tensioner - see the info on web here http://kleinanzeigen.ebay.de/anzeig...-opel-z22se-y22yh-z20net-gm-12608580/25401281
should exist.

Field remedy 2366 (Opel Feldabhilfe 2366 equivalent given by Rhil Harisson expert on http://www.justanswer.com):

Subject: Engine Z22SE/Z22YH, tensioner timing chain - Rattling noise from timing chain
Models:
Vectra-B 2001...2003,Astra-G 2001...2004,Zafira 2001...2004,Speedster 2001...2004,VX220 2001...2004,Zafira-B 2005...2009,Astra-H 2007...2009,Vectra-C 2004...2009,Signum 2003...2009
Engines: Z22SE,Z22SE,Z22SE,Z22SE,Z22SE,Z22YH,Z22YH,Z22YH,Z22YH
Complaint: Rattling noise from timing chain, often together with elongated timing chain.
Cause: Blocked timing chain tensioner.
Production: A modified Z20NET tensioner will be introduced in production with MY 2009.
Remedy:
Note: For Z22SE engines please first take note of Quick Information 1532.
In case of customer complaint exchange timing chain and install Z20NET timing chain tensioner part-no.: 12608580 / catalogue-no.: 48 07 839.

(I am from Slovakia, therefore addressing GM Opel).
My questions that Opel is not willing to answer, are the following:

1. Opel statement to using the Z20NET tensioner in Z22SE type engines
2. Opel ordering code for the Z20NET type tensioner
3. Opel ordering code for the Timing Chain Kit containing the Z20NET type tensioner
4. Functional principle of the Z20NET tensioner - is its function dependent on spring only or engine oil pressure is engaged as well ?
5. Way of initialization of the Z20NET tensioner before its installation and after installing it into the engine camchain drive.

So, except the above introduced Field Remedy 2366 info, it is further possible to use the unofficial information only as it may be found on web.
 
#7
quick question the tensioner for z22se engine when installed the pin that hold the segment with shaped slot, 7 pin in the piston has that got to stay in the frirst grove just about above the a on the picture above is just simply line it to the tention bar and screw it tight and it will do its job bassicly
 

Daz

Former Staff
Senior Member
#18
Activate tensioner. And the push it in and screw into the head

Sent from my GT-I9300 using Tapatalk 2
 

evocarlos

Stupid Bollocks
Staff
#19
Activate tensioner. And the push it in and screw into the head

Sent from my GT-I9300 using Tapatalk 2
cool i found the problem all the slack was at the front and to wind it round a touch but there another problem lol

and it is real easy to activate when its in the block i just used a file and pressed it a few times
only problem is the chain is a bit long for the cogs :(
 
#20
Hi, Your name was forwarded to me by Persia-Chris regarding a timing chain replacement. I hope to have a Vectra B 2.2 SRi 2002. 56K on the clock, FSH by Vauxhall dealer, one owner, excellent condition. No record of a timing chain replacement on record.
There is so much negative chat about the 2.2 timing chain. Is there any way l could check the timing chain before buying the car? Is it essential to get it done asap after buying it?
It is a nice car, but concerned about the failure rate of the chain.
I am in Dorset. Do you do the job in a day?
Hope to hear from you soon
 
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