Diff filler plug removal

This forum is specifically for engine and gearbox posts, please try to keep on topic in any thread to make things easy to find

Moderator: Board Moderators

Post Reply
User avatar
Atking53
Junior Poster
Posts: 32
Joined: Sat May 05, 2018 08:05
Model: Excel LC
Colour: White
Year: 1985
Location: Wilton NSW

Diff filler plug removal

Post by Atking53 »

My '85 LC Excel had the diff oil replaced about 3 years ago but seals are leaking a bit so I thought I should check oil levels. Seems the last mechanic rounded the head of the filler nut and I can't remove it. Firstly any thoughts on how to remove it now. Secondly I opened the drain plug and lost all the oil (500ml). Has anyone been able to refill the diff via the drain hole without turning the car upside down and how much oil does the diff hold? What viscosity should I use?
Glenn
Lotus Excel
Mercedes SL350
Hyundai i30 SR

User avatar
bash
Senior Poster
Posts: 2284
Joined: Thu Nov 03, 2005 15:34
Model: Se, V8
Colour: white
Year: 1986
Location: Doncaster
Contact:

Re: Diff filler plug removal

Post by bash »

I think you can get the diff end cover off without taking the diff out, or, an easier way is to remove a drive shaft and pop out one of the output shafts (its just clipped into the diff so levers out ) to get some oil back in the diff if you really need to get moving again. Ultimately its worth sorting the filler plug. When the covers off welding a bigger (longer head) nut onto the old one is the way to go. The heat from the weld will release the old nut and it will be easier to remove next time. The standard toyota nut is far too shallow and they regularly round off.
Bash
Two things are infinite: the universe and human stupidity; and I'm not sure about the universe.

User avatar
Atking53
Junior Poster
Posts: 32
Joined: Sat May 05, 2018 08:05
Model: Excel LC
Colour: White
Year: 1985
Location: Wilton NSW

Re: Diff filler plug removal

Post by Atking53 »

Thanks Bash, I certainly considered whether the cover could come off. Well worth a try. Welding a bigger nut will definitely solve future problems. Cheers
Glenn
Lotus Excel
Mercedes SL350
Hyundai i30 SR

User avatar
Atking53
Junior Poster
Posts: 32
Joined: Sat May 05, 2018 08:05
Model: Excel LC
Colour: White
Year: 1985
Location: Wilton NSW

Re: Diff filler plug removal

Post by Atking53 »

I just tried 6 of the 8 studs in the diff cover and they all come loose so will wait until tomorrow with dirty clothes and tackle the rest. I gave then a squirt of WD40 overnight. here's hoping. :)
Glenn
Lotus Excel
Mercedes SL350
Hyundai i30 SR

Johnwindwood
Senior Poster
Posts: 473
Joined: Sat Mar 25, 2017 14:34
Model: 1984 Excel
Colour: Monaco White
Year: 1984
Location: walsall

Re: Diff filler plug removal

Post by Johnwindwood »

If it's the driveshaft seals leaking, try cleaning or replacing the breather on top. Changed ours because of driveshaft leaks and they stopped.
Knew it was the right thing to do - when I removed it, I got a hiss of pressure being released !
Kind regards

John

John Windwood

1984 Lotus Excel (1985 MY wide body)
1952 Austin Sheerline A125 Harold Radford Shooting Brake
1949 Austin Sheerline saloon (Parts car)
1997 BMW Z3 1.9
2002 Volvo V70XC Cross Country AWD

User avatar
Atking53
Junior Poster
Posts: 32
Joined: Sat May 05, 2018 08:05
Model: Excel LC
Colour: White
Year: 1985
Location: Wilton NSW

Re: Diff filler plug removal

Post by Atking53 »

It was necessary to remove the diff rear housing. Very tight but does come off and on if you twist it the right way and the right hand lower link (suspension) bolt is screwed out of the way. Housing comes off with 12mm sockets and a short ratchet wrench. The plug still took 4 hours to remove but done and replaced with a new one. Breather on top was gunked up so cleaned that as well. It was surprisingly difficult to refill the diff with oil. A cheap drill pump would have made it easier. Thanks for the help.
Glenn
Lotus Excel
Mercedes SL350
Hyundai i30 SR

User avatar
bash
Senior Poster
Posts: 2284
Joined: Thu Nov 03, 2005 15:34
Model: Se, V8
Colour: white
Year: 1986
Location: Doncaster
Contact:

Re: Diff filler plug removal

Post by bash »

Well done dude. Gearbox is another one to watch, dont undo the drain plug till the filler is loose otherwise you will be adding oil via the gearstick hole.
Bash
Two things are infinite: the universe and human stupidity; and I'm not sure about the universe.

User avatar
robertverhey
Senior Poster
Posts: 788
Joined: Tue Nov 01, 2005 10:54
Year: 0
Location: Sydney
Contact:

Re: Diff filler plug removal

Post by robertverhey »

It’s a while ago but I remember my filler plug rounded as well. I filed the flats until the next socket down (size-wise) fitted on. 7/8” from memory.
Robert Glacier Blue '87 SE

Post Reply