Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: Shackeng on 23 March 2017, 13:27:24

Title: Gearbox problem
Post by: Shackeng on 23 March 2017, 13:27:24
After replacing the tthrust washer last year, the AR35 box on the TD has been fine until the last few days. Occasionally it behaves like a slipping clutch on a manual. Oil level and colour is fine. What could this be?
Title: Re: Gearbox problem
Post by: Shackeng on 23 March 2017, 19:47:53
Any thoughts?
Title: Re: Gearbox problem
Post by: Andy H on 23 March 2017, 19:57:00
Any obvious triggers? Is it repeatable or random?

- faulty solenoid?
- worn out friction material?
- insufficient oil pressure to actuate the clutches? (maybe a result of damage to the oil pump? :-\)
Title: Re: Gearbox problem
Post by: Shackeng on 23 March 2017, 22:19:27
Any obvious triggers? If worked hard and giving it beans.Is it repeatable or random? Yes and Yes

- faulty solenoid? Is this a symptom of a faulty solenoid?
- worn out friction material? Is this likely to occur?
- insufficient oil pressure to actuate the clutches? (maybe a result of damage to the oil pump? :-\) Would that give this effect?

Thanks :y

Title: Re: Gearbox problem
Post by: Chazza12 on 24 March 2017, 08:08:20
check its gearbox control unit, if the seal on the connector getting a good fit as water or condensation can get in and cause problems. speedo signal etc goes out and in to the unit for the ecu. it can make similar problems and be erratic. 
Title: Re: Gearbox problem
Post by: Shackeng on 24 March 2017, 08:30:14
Can't say it is erratic, just that when it has been worked hard, it can behave just like a slipping clutch on a manual box. :-\ :-\ :-\
Title: Re: Gearbox problem
Post by: Doctor Gollum on 24 March 2017, 09:19:07
Sounds like clutches getting tired then :-\
Title: Re: Gearbox problem
Post by: Kevin Wood on 24 March 2017, 10:03:33
Yes, probably wear to the clutches or an oil pump problem not keeping them engaged, although I believe line pressure is monitored so it'd probably put it into limp home.

Brake band adjustment might be worth a try before condemning it.
Title: Re: Gearbox problem
Post by: Shackeng on 24 March 2017, 19:22:52
Thanks guys, remind me where the clutches are, and how to adjust the brake band. :y
Title: Re: Gearbox problem
Post by: Andy H on 24 March 2017, 22:18:19
Thanks guys, remind me where the clutches are, and how to adjust the brake band. :y
Does this help  ;)

(http://i1250.photobucket.com/albums/hh529/buctuong_lua16/4L30ETransmissonRepairManual_1.jpg)
Title: Re: Gearbox problem
Post by: Andy H on 24 March 2017, 22:24:21
I tried looking at the oil pressure in the project MV6 box this afternoon - hot engine, engine running and box in drive.

Looks as though 5 bar is the required pressure. Do you have any way of reading your gearbox ECU? I was thinking that a missing thrust washer might have allowed damage to occur to the pump  :-\

(http://homepages.nildram.co.uk/~aholter/Screenshot_2017-03-24-16-46-00.png)
Title: Re: Gearbox problem
Post by: Shackeng on 24 March 2017, 23:05:57
Thanks Andy, useful diagram. I have the spare Carlton AR35 from which I could steal the clutch plates. Annoying as I could have done that while I had the box off to replace the thrust washer, and as I have said elsewhere, I don't want to do such heavy stuff anymore. :(
Title: Re: Gearbox problem
Post by: Shackeng on 25 March 2017, 09:32:41
I tried looking at the oil pressure in the project MV6 box this afternoon - hot engine, engine running and box in drive.

Looks as though 5 bar is the required pressure. Do you have any way of reading your gearbox ECU? I was thinking that a missing thrust washer might have allowed damage to occur to the pump  :-\

(http://homepages.nildram.co.uk/~aholter/Screenshot_2017-03-24-16-46-00.png)

Unfortunately no, but I did have a failed thrust washer. :y
Title: Re: Gearbox problem
Post by: RobG on 25 March 2017, 11:52:43
Thanks guys, remind me where the clutches are, and how to adjust the brake band. :y
When the sump is removed there is a dome held on with 3 or 4 bolts. Remove it and there is a threaded screw with a lock nut, release it then tighten the screw to 5nm torque, back off five turns and then tighten the lock nut, this sets the brake band. Replace the dome then it`s a gearbox re-fill
Title: Re: Gearbox problem
Post by: Shackeng on 25 March 2017, 12:17:42
Thanks guys, remind me where the clutches are, and how to adjust the brake band. :y
When the sump is removed there is a dome held on with 3 or 4 bolts. Remove it and there is a threaded screw with a lock nut, release it then tighten the screw to 5nm torque, back off five turns and then tighten the lock nut, this sets the brake band. Replace the dome then it`s a gearbox re-fill
Thanks Rob, at least i can try that without removing the box. I assume its under the larger rear sump? :y
Title: Re: Gearbox problem
Post by: Andy H on 25 March 2017, 12:45:26
Have a search for 4L30E repair procedures and this guide pops up http://scottj.info/files/isuzu/4l30e.pdf (http://scottj.info/files/isuzu/4l30e.pdf). Lots of words and pictures - the procedure, on page 79, for adjusting the brake piston looks plausible enough.
Title: Re: Gearbox problem
Post by: Shackeng on 25 March 2017, 15:33:07
Have a search for 4L30E repair procedures and this guide pops up http://scottj.info/files/isuzu/4l30e.pdf (http://scottj.info/files/isuzu/4l30e.pdf). Lots of words and pictures - the procedure, on page 79, for adjusting the brake piston looks plausible enough.

Cheers Andy. I'm puzzled that it should require resetting though. My gut pessimists feeling is that it is more likely the clutches. :y
Title: Re: Gearbox problem
Post by: Doctor Gollum on 25 March 2017, 15:59:59
The brake bands are presumably a wearing part, so tweaking isn't unreasonable  :-\
Title: Re: Gearbox problem
Post by: TheBoy on 25 March 2017, 17:13:59
I suspect you may be better just throwing on another AR35. Sorry.
Title: Re: Gearbox problem
Post by: Shackeng on 25 March 2017, 19:02:05
I suspect you may be better just throwing on another AR35. Sorry.

Still an option.
Title: Re: Gearbox problem
Post by: Shackeng on 02 April 2017, 19:41:42
Thanks guys, remind me where the clutches are, and how to adjust the brake band. :y
When the sump is removed there is a dome held on with 3 or 4 bolts. Remove it and there is a threaded screw with a lock nut, release it then tighten the screw to 5nm torque, back off five turns and then tighten the lock nut, this sets the brake band. Replace the dome then it`s a gearbox re-fill

I'm going to tackle this shortly. Which sump is it under? I don't recall a dome under the filter in the rear sump. :-\ :-\ :-\
Title: Re: Gearbox problem
Post by: Shackeng on 03 April 2017, 16:21:49
Thanks guys, remind me where the clutches are, and how to adjust the brake band. :y
When the sump is removed there is a dome held on with 3 or 4 bolts. Remove it and there is a threaded screw with a lock nut, release it then tighten the screw to 5nm torque, back off five turns and then tighten the lock nut, this sets the brake band. Replace the dome then it`s a gearbox re-fill

I'm going to tackle this shortly. Which sump is it under? I don't recall a dome under the filter in the rear sump. :-\ :-\ :-\

Can anyone remember which sump?
Title: Re: Gearbox problem
Post by: Steve B on 03 April 2017, 16:43:21
Wait for conformation But i think Rob means this in the big sump

(https://www.dropbox.com/s/jzmzbnd36j1lx91/boxsump.jpg?dl=0)

That never went well  ;D ;D
Title: Re: Gearbox problem
Post by: Steve B on 03 April 2017, 17:03:31
(https://photos-5.dropbox.com/t/2/AADQusLb91eWEGRoAbab_vnJHvr_ytsLanJukyaSiZ63dg/12/70807181/jpeg/256x256/1/_/1/2/boxsump.jpg/ENy0ijcYsgkgAigC/l0kR9IWA4TU8gI6dBKfKGu0I9cBFpF8c8P4wok2reQk?size=2048x1536&size_mode=3)
Title: Re: Gearbox problem
Post by: Shackeng on 03 April 2017, 18:23:43
If anyone knows the answer to this I would be grateful, as I had both sumps off a few months ago, and do not want to take them both off again, if I can get away with one, and I would like to get on with it tomorrow. :y
Title: Re: Gearbox problem
Post by: Shackeng on 03 April 2017, 19:27:15
OK, found this which shows how to do it in the rear sump.  :y
https://www.youtube.com/watch?v=bHWDxAwhzYc