Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: Omegafantasy on 21 November 2009, 02:44:07

Title: X25XE breakdown - heading for Y26SE
Post by: Omegafantasy on 21 November 2009, 02:44:07
Hello there, dear Omega-people  :)
I'm new to this forum (well, I've been lurking for some time, but found out it was time to open my mouth a bit). You seem dedicated to this wonderful piece of machinery and a lot of expertise is found around these forums.

Anyway, I hope I can abuse some of that expertise now (please don't flame me, I'll help whenever I can  ;) )
I've been looking all around this forum (and others), but couldn't find useful info on these subjects.

The death of a V6
I bought my '95 Omega 2.5 with a blown engine. I had the engine replaced and of course I fitted a new cambelt. Since I didn't have the tools or experience with the V6 I had a professional mechanic with the right tools do it. What I noticed was that the old cambelt was worn a few millimeters on the outside and a lot of cambelt residue/dust was covering the inside of the cambelt housing. The mechanic said this was normal on the V6 and it didn't really matter. After some days of driving I saw that my new cambelt was tearing away exactly like the old one. I did NOT change the tensioners (on advice) since the old kit was replaced about 4000 miles earlier.
A couple of weeks back I noticed that my engine was hesitating a bit and didn't quite feel "normal". I was driving slow due to traffic so no reving above 2000 rpm as far as I can remember. At an intersection my car almost stopped, made a few hickups and sounded like it was running on 4-5 cylinders. I stopped outside a mate's place and listened to the engine for a while. There was some kind of faint "whirring" sound, but I couldn't determine what it was. I touched the throttle a bit, reving it to approx. 1800 rpm when I heard a loud "clunk clunk snap gurgle" with the unmistakeable sound of metal objects hitting each other. The engine now sounded like a three cylinder engine. I knew what happened.. Towing the car home, dismantling ancilliary devices and the cambelt cover and saw this:

(http://omcoslo.com/omega/18112009038.jpg)
Tensioner not engaged at all?

(http://omcoslo.com/omega/18112009039.jpg)
Worn belt..

(http://omcoslo.com/omega/18112009040.jpg)
Bits and pieces of cambelt everywhere.

(http://omcoslo.com/omega/18112009041.jpg)
Shredded.

I think it's safe to say that some valves are bent, this just can't be in time anymore - as far as I know. Not sure if it "jumped a tooth" or two, but cambelt with slack can't be good.

Raised from the dead
Anyway, I got me a new engine today - a 2001 Y26SE with only 74000 miles. Cambelt + kit changed (documented) about 1000 miles ago (poor Omega got rear ended). I did not get the flywheel, ECU or wiring loom for it, but I'm pretty sure I can get this working with my X25XE parts (in fact I have two broken).
Do any of you have hints or useful advices for me regarding this change?
Issues I can see straight away:
- No EGR-system on the Y26SE
- Coil pack must be fitted (although original coils are there)
- Flywheel (and new bolts) must be fitted (flywheel is the same right?)
- Some sensors must be moved over to fit my old wiring loom

I hope this wasn't too much  :o I know it's a wall of text, but I'm Norwegian and we tend to type a lot  ;D (and please excuse my English)
Title: Re: X25XE breakdown - heading for Y26SE
Post by: tunnie on 21 November 2009, 09:19:47
you should be able to swap over the heads, since you don't have the DBW stuff and other leccy stuff.

But keep using the DIS pack and other bits
Title: Re: X25XE breakdown - heading for Y26SE
Post by: feeutfo on 21 November 2009, 10:05:47
i was wondering if the 2.6 heads will accept the 2.5 cam covers plugs leads dis? Then stick the 2.5 plenum on top?
Title: Re: X25XE breakdown - heading for Y26SE
Post by: tunnie on 21 November 2009, 10:44:32
Quote
i was wondering if the 2.6 heads will accept the 2.5 cam covers plugs leads dis? Then stick the 2.5 plenum on top?

I was wondering the same, not sure if its best to try and use 2.5 cam covers or 2.6  :-/

After all 2.6 covers are basically the same as far as i know, just plug leads in rather than coil pack?  :-/
Title: Re: X25XE breakdown - heading for Y26SE
Post by: Omegafantasy on 21 November 2009, 10:55:46
Quote
you should be able to swap over the heads, since you don't have the DBW stuff and other leccy stuff.

But keep using the DIS pack and other bits

Ouch, a head change isn't exactly what I was looking for now, it kinda of ruins the reason for getting a new engine.

Think I'll try to build it like the X25XE, it can't be that much, or would I be better off if I got the wiring loom and ECU from Y26SE?
Title: Re: X25XE breakdown - heading for Y26SE
Post by: feeutfo on 21 November 2009, 10:56:16
Quote
Quote
i was wondering if the 2.6 heads will accept the 2.5 cam covers plugs leads dis? Then stick the 2.5 plenum on top?

I was wondering the same, not sure if its best to try and use 2.5 cam covers or 2.6  :-/

After all 2.6 covers are basically the same as far as i know, just plug leads in rather than coil pack?  :-/
Fairly sure would have be 2.5 ignition due to loom and ecu?
Title: Re: X25XE breakdown - heading for Y26SE
Post by: tunnie on 21 November 2009, 10:58:27
Quote
Quote
you should be able to swap over the heads, since you don't have the DBW stuff and other leccy stuff.

But keep using the DIS pack and other bits

Ouch, a head change isn't exactly what I was looking for now, it kinda of ruins the reason for getting a new engine.

Think I'll try to build it like the X25XE, it can't be that much, or would I be better off if I got the wiring loom and ECU from Y26SE?

Problem you have is the 2.6 is DBW (Drive by Wire) so the throttle is electronic, compared to cable on the 2.5. Also uses coil packs rather than DIS pack, you will need the ECU from the 2.6

Other way is to keep the 2.5 block, fit 2.6 heads (with working valves!) and then use your current DIS pack and plenum (although need someone to confirm you can fit a 2.5 plenum on 2.6)
Title: Re: X25XE breakdown - heading for Y26SE
Post by: Marks DTM Calib on 21 November 2009, 11:00:37
No need to touch the heads (they are the same), just swap the cam covers over and fit the dis mounting bracket to the rear of the 2-4-6 head.

Fit the sensors and wiring loom from the 2.5.

EGR can be worked around so as to keep the ECU happy.
Title: Re: X25XE breakdown - heading for Y26SE
Post by: Omegafantasy on 21 November 2009, 11:09:15
Quote
Quote
Quote
you should be able to swap over the heads, since you don't have the DBW stuff and other leccy stuff.

But keep using the DIS pack and other bits

Ouch, a head change isn't exactly what I was looking for now, it kinda of ruins the reason for getting a new engine.

Think I'll try to build it like the X25XE, it can't be that much, or would I be better off if I got the wiring loom and ECU from Y26SE?

Problem you have is the 2.6 is DBW (Drive by Wire) so the throttle is electronic, compared to cable on the 2.5. Also uses coil packs rather than DIS pack, you will need the ECU from the 2.6

Other way is to keep the 2.5 block, fit 2.6 heads (with working valves!) and then use your current DIS pack and plenum (although need someone to confirm you can fit a 2.5 plenum on 2.6)

I don't see any reason why the 2.5 plenum shouldn't fit on the 2.6, but I'll try later today when I get to my workshop. What I don't understand is why do I have to change the heads? They look pretty much the same to me (connection-wise). A head job (:p) would cost me close to £1000  :(
Title: Re: X25XE breakdown - heading for Y26SE
Post by: tunnie on 21 November 2009, 11:11:22
Quote
Quote
Quote
Quote
you should be able to swap over the heads, since you don't have the DBW stuff and other leccy stuff.

But keep using the DIS pack and other bits

Ouch, a head change isn't exactly what I was looking for now, it kinda of ruins the reason for getting a new engine.

Think I'll try to build it like the X25XE, it can't be that much, or would I be better off if I got the wiring loom and ECU from Y26SE?

Problem you have is the 2.6 is DBW (Drive by Wire) so the throttle is electronic, compared to cable on the 2.5. Also uses coil packs rather than DIS pack, you will need the ECU from the 2.6

Other way is to keep the 2.5 block, fit 2.6 heads (with working valves!) and then use your current DIS pack and plenum (although need someone to confirm you can fit a 2.5 plenum on 2.6)

I don't see any reason why the 2.5 plenum shouldn't fit on the 2.6, but I'll try later today when I get to my workshop. What I don't understand is why do I have to change the heads? They look pretty much the same to me (connection-wise). A head job (:p) would cost me close to £1000  :(

I was way off , check DTM's post for a much simpler life  ;D  :y
Title: Re: X25XE breakdown - heading for Y26SE
Post by: Omegafantasy on 21 November 2009, 11:12:21
Quote
No need to touch the heads (they are the same), just swap the cam covers over and fit the dis mounting bracket to the rear of the 2-4-6 head.

Fit the sensors and wiring loom from the 2.5.

EGR can be worked around so as to keep the ECU happy.

Thank you  :) This was more like what I was hoping for. The EGR is probably a minor issue. As long as I keep the valve in the circuitry or some dummy load to make the ECU believe it's there I won't get any errors.

Will have a closer look at the engines later today.
Title: Re: X25XE breakdown - heading for Y26SE
Post by: Andy H on 21 November 2009, 11:53:08
The 2.6 exhaust manifolds are lighter and more free flowing than the 2.5 items.

The 2.5 exhaust manifolds have the EGR port and a deep recess for the exhaust downpipe to engage with

The quick fix is to reuse the 2.5 exhaust manifolds.

The better performance/economy route involves overcoming the EGR problem and grinding off some of the lip on the downpipes so that they fit the manifolds.

There is a description here somewhere about improving a 2.5 using 2.6 heads & manifolds. A lot of the information should be relevant to you.
Title: Re: X25XE breakdown - heading for Y26SE
Post by: Martin_1962 on 21 November 2009, 14:41:40
Block off EGR and use the 2.6 with a DIS pack and 2.5 plenum

Modify down pipes to accept the 2.6 manifolds

The 2.6 head article was Mikes overhaul
Title: Re: X25XE breakdown - heading for Y26SE
Post by: Andy H on 21 November 2009, 14:46:01
Quote
The 2.6 head article was Mikes overhaul
I have trawled through months of posts trying to find it but can't :(

Would probably be good to add it to the 'maintenance guides' because it covered so many gotchas?
Title: Re: X25XE breakdown - heading for Y26SE
Post by: Martin_1962 on 21 November 2009, 14:51:47
Quote
Quote
The 2.6 head article was Mikes overhaul
I have trawled through months of posts trying to find it but can't :(

Would probably be good to add it to the 'maintenance guides' because it covered so many gotchas?


Not in my bookmarks :(
Title: Re: X25XE breakdown - heading for Y26SE
Post by: Andy H on 21 November 2009, 15:09:08
Quote
Quote
The 2.6 head article was Mikes overhaul
I have trawled through months of posts trying to find it but can't :(

Would probably be good to add it to the 'maintenance guides' because it covered so many gotchas?
Good man! all it needed was the magic word (overhaul) and search found it straight away.

http://www.omegaowners.com/forum/YaBB.pl?num=1236287115/all

Going to add it to my bookmarks  :y
Title: Re: X25XE breakdown - heading for Y26SE
Post by: Omegafantasy on 21 November 2009, 15:11:06
Quote
Block off EGR and use the 2.6 with a DIS pack and 2.5 plenum

Modify down pipes to accept the 2.6 manifolds

The 2.6 head article was Mikes overhaul

Thank you Martin and Andy.
I will look for the article or some other info on the downpipe mod. Using the 2.5 manifolds could also work, but that involves waiting some weeks for gaskets (welcome to Norway). Getting parts here is difficult, you either pay 10 times more than normal, or you have to wait forever...
Title: Re: X25XE breakdown - heading for Y26SE
Post by: Martin_1962 on 21 November 2009, 16:26:22
2.6 flow better - using 2.5 will lower the power output
Title: Re: X25XE breakdown - heading for Y26SE
Post by: Andy H on 21 November 2009, 19:31:53
http://www.omegaowners.com/forum/YaBB.pl?num=1236287115/all

Almost forgot. The SAI system will be redundant. Stripping that lot out makes access easier and is one less item to go wrong.
Title: Re: X25XE breakdown - heading for Y26SE
Post by: Omegafantasy on 21 November 2009, 19:39:19
Quote
http://www.omegaowners.com/forum/YaBB.pl?num=1236287115/all

Almost forgot. The SAI system will be redundant. Stripping that lot out makes access easier and is one less item to go wrong.

I always wanted to get rid of that system anyway. Sounds like a vacuum cleaner when you start the engine  :-/

I just wonder how well the engine will work with the stock X25XE ECU/mapping. Would it be wise to order some kind of chip for it? I see they're available on ebay, but never got around to order one.
Title: Re: X25XE breakdown - heading for Y26SE
Post by: Omegafantasy on 23 November 2009, 11:18:01
I'm currently at work so I'm not able to check myself, but does anyone know if the X25XE and Y26SE use the same flywheel bolts?
Title: Re: X25XE breakdown - heading for Y26SE
Post by: Kevin Wood on 23 November 2009, 12:51:12
Quote
Quote
http://www.omegaowners.com/forum/YaBB.pl?num=1236287115/all

Almost forgot. The SAI system will be redundant. Stripping that lot out makes access easier and is one less item to go wrong.

I always wanted to get rid of that system anyway. Sounds like a vacuum cleaner when you start the engine  :-/

I just wonder how well the engine will work with the stock X25XE ECU/mapping. Would it be wise to order some kind of chip for it? I see they're available on ebay, but never got around to order one.

It'll be perfectly OK. Not enough difference in engine spec. to make any difference.  :y

Kevin
Title: Re: X25XE breakdown - heading for Y26SE
Post by: Marks DTM Calib on 23 November 2009, 15:33:51
Quote
I'm currently at work so I'm not able to check myself, but does anyone know if the X25XE and Y26SE use the same flywheel bolts?

Yep.
Title: Re: X25XE breakdown - heading for Y26SE
Post by: Omegafantasy on 26 November 2009, 18:58:33
Ok, a little update on this while I'm having a coffee before I head to the workshop:

Yesterday, I started the small operation with modifying electronics on the 2.6. I wonder, would it be possible for me to use the standard coils already fitted on the Y26SE? I think yes if I can get the connectors, wiring schematics and a little bit of hope.

Otherwise, it will look like this if i remove the coils and insert my standard cables:
(http://omcoslo.com/omega/25112009059r.jpg)

It won't seal around the holes so it would fill up with dirt and water. Maybe just make a perfect-fit shield to cover it? I have the gaskets so.. Changing the cam covers is also possible, but then I have to wait some weeks for new gaskets to arrive (although, I have gaskets for one side).

Next up tonight is cleaning the plenum, throttle body and hoses. Breathers look ok, but on my 2.5 vaccuum/breather-plastic-thingy, one pipe is blocked. Not sure what it's for, but it's the one with a hose connected to a valve (third connector from left seen from the back). I'll see if I can unclog it. Should I clean the metal block from the engine too? I see there's some mayo down there, but not really dirty. I'll have a look at similar posts on the forums regarding breather cleaning..