1968 780 Rebuild (lots of photos)

This is for members to post photos of their restorations, either completed or "works in progress"

Moderators: Segrie61, admin

User avatar
dsk
Posts: 306
Joined: Thu May 06, 2010 2:42 pm
Location: Caithness

RE: 1968 780 Rebuild (lots of photos)

Post by dsk » Sat Aug 07, 2010 8:53 pm

Pimp my ride, farm stylee!

Image

Well there was no paint left on it anyway so why not. :)

However someone in the past has tried to encourage it with a very large hammer, and there are no longer either of the two locating pins behind there. Can anyone suggest an easy fix or would I be as well to fit the mechanism from another tractor.
780 880 990

User avatar
dsk
Posts: 306
Joined: Thu May 06, 2010 2:42 pm
Location: Caithness

RE: 1968 780 Rebuild (lots of photos)

Post by dsk » Sun Aug 08, 2010 2:57 pm

I said before that I wondered why there was no short setting with this drawbar. Just like to add that I did eventually work out the obvious.
Image
780 880 990

User avatar
dsk
Posts: 306
Joined: Thu May 06, 2010 2:42 pm
Location: Caithness

RE: 1968 780 Rebuild (lots of photos)

Post by dsk » Fri Aug 27, 2010 8:35 pm

Took apart a scrap PTO today. So I now have the parts for a two speed drive. It came apart straight forward enough. Anything I should be aware of when I rebuild it?
Image
780 880 990

User avatar
dsk
Posts: 306
Joined: Thu May 06, 2010 2:42 pm
Location: Caithness

RE: 1968 780 Rebuild (lots of photos)

Post by dsk » Wed Sep 08, 2010 4:45 pm

Finally getting closer to the heart of things. The engine is seized and wasn't too healthy before that, so off with her head. Only one bore with water in, but it looks like this motor has liners? Its not technically supposed to be but after 40 years anything is possible.
Image

Image
780 880 990

User avatar
calvin
Posts: 490
Joined: Sun Apr 04, 2010 10:41 pm
Location: ireland / northern ireland

RE: 1968 780 Rebuild (lots of photos)

Post by calvin » Thu Sep 09, 2010 7:49 pm

were can i get sweet sorghum syrup ???
3 pot , 4 pot and the MIGHTY 6 POTT!

Guest

RE: 1968 780 Rebuild (lots of photos)

Post by Guest » Thu Sep 09, 2010 8:42 pm

Are the bores too rusted to clean up? May pay just to clean up to see how far they've gone. If they are badly rusted then an engine overhaul kit would be your best bet and probably the way to go especially if there are sleeves in the bores, half done for you already. Look at the link. Retail for this kit is about £251.13 plus vat which will give you somewhere to start pricing up kits. This kit is supplied with everything you will need to rebuild the engine except shell and main bearings but includes all the gaskets. If you click on 'kit contents' you'll see what's in it.

http://www.vapormatic.com/catalogue/cat ... tDown=True

User avatar
dsk
Posts: 306
Joined: Thu May 06, 2010 2:42 pm
Location: Caithness

RE: 1968 780 Rebuild (lots of photos)

Post by dsk » Thu Sep 09, 2010 9:13 pm

Not sure about sweet sorghum in particular, we just call it all treacle to be honest. Although I am told that animal feed grade stuff is best as it is less refined. So any good agricultural animal feed merchant. Although I beleive it doesn't react well with metals like aluminium or zinc.

Thanks for the link Powerrabbit. I have saved the bore in another engine by using a chemical called DeoxC from Bilt Hamber to dissolve the rust. More expensive than treacle but it works with aluminium. However the bores have a good deep step in them so its time for a proper rebuild.
780 880 990

User avatar
dsk
Posts: 306
Joined: Thu May 06, 2010 2:42 pm
Location: Caithness

RE: 1968 780 Rebuild (lots of photos)

Post by dsk » Sat Sep 11, 2010 8:42 pm

I dropped the oil. It kinda fell out slowly in thick lumps. I have not pulled the sump off yet but I can see that number one piston was hitting the head due to the big end bearing gone.

No photo today but I felt I had better fit the pto parts while they are sitting here. So the back end is open and I will fit the new oil pump at the same time.
The end shaft of the pto was making a really horrible rumble so I had hoped to use the bearings from the 996 I took the new gears from. However the 996 has taper bearings at both ends of the shaft (which you can add shims to tighten) whereas the 780 uses a needle bearing on the inner end just like the shaft above. And it turns out that both needle bearings were indeed ... shafted.
I also see that the pump drive on the 780 has straight cut teeth and the 996 helical. I noticed this once before between two 880s. I don't think there is any benefit to changing them so I will leave them as original.
780 880 990

User avatar
dsk
Posts: 306
Joined: Thu May 06, 2010 2:42 pm
Location: Caithness

RE: 1968 780 Rebuild (lots of photos)

Post by dsk » Sun Sep 19, 2010 8:57 pm

I had to buy a better set of circlip pliers, but I got it all back together. £10.50 for one new bearing and re-used four perfectly good ones. I ended up using the helical transfer gears to the pump from the 996. The bearings were just that much better that it was more hassle not to. Funny thing (especially as I am Scottish) is how good it is to see "Made In England" stamped on all of them.

I also managed to clean out two broken bolts from the bell housing that hold the drawbar. Wasted a lot of time on that but it was worth it. I also noticed that the 996 has a guard that shields the oil pressure switch underneath so I thought I might as well keep that too.

I bought two 885 reductions in good order from Guy Hall which will save me rebuilding both the reductions on the tractor. With someone collecting it for me while they were south, it cost less than a new oil seal. So I bought a really good 885 dash panel while I was at it. 8) I should also say that I had a birthday not long ago and bought the Service Day video from the club shop. I can thoroughly recommend it. Really well done and worth it to me just to see the clutch come apart.

Image
780 880 990

User avatar
Madders
Posts: 2433
Joined: Tue Feb 28, 2006 9:52 pm
Location: Holmfirth

RE: 1968 780 Rebuild (lots of photos)

Post by Madders » Sun Sep 19, 2010 9:48 pm

You're keen I'll give you that!!!! lol!!!
[.................................[/size] Image

User avatar
nzjoe
Posts: 10
Joined: Wed Aug 04, 2010 3:54 am
Location: new zealand

RE: 1968 780 Rebuild (lots of photos)

Post by nzjoe » Mon Sep 20, 2010 7:15 am

I am watching your site with interest, as i have a 780 Narrow already restored.,This was featured on the front cover of Sep issue of Tractor and Machinery. Also I have a 1968 770 that I have already started on. I think your'e on the right track with your replacement final drives, as long as there is oil in them they should be good.

User avatar
nzjoe
Posts: 10
Joined: Wed Aug 04, 2010 3:54 am
Location: new zealand

RE: 1968 780 Rebuild (lots of photos)

Post by nzjoe » Mon Sep 20, 2010 7:16 am

I am watching your site with interest, as i have a 780 Narrow already restored.,This was featured on the front cover of Sep issue of Tractor and Machinery. Also I have a 1968 770 that I have already started on. I think your'e on the right track with your replacement final drives, as long as there is oil in them they should be good.

User avatar
dsk
Posts: 306
Joined: Thu May 06, 2010 2:42 pm
Location: Caithness

Re: RE: 1968 780 Rebuild (lots of photos)

Post by dsk » Mon Sep 20, 2010 8:51 pm

Madders wrote:You're keen I'll give you that!!!! lol!!!
I'll take that as a compliment, I think.

Joe, I don't buy many magazines but I did read that one. Image

Image
780 880 990

User avatar
dsk
Posts: 306
Joined: Thu May 06, 2010 2:42 pm
Location: Caithness

RE: Re: RE: 1968 780 Rebuild (lots of photos)

Post by dsk » Thu Sep 30, 2010 6:05 pm

How many extra hydraulic fittings do you reckon I might need? :)
Image
Thanks go to Joe Proctor for selling me these. They still need a bit of work and a clean, but until I get round to that, on the tractor seems the safest place to store them.
I don't have a need for both valve blocks so I intend to split this and fit one block to the 780 and one to the 880. Can anyone tell me if the top and base plates from a 1212 might be suitable for use on the 880?

I took a look at some lift latch covers to see what I can do about the missing pins. Some photos to help explain.
Image
Image
I don't see an easy way of replacing those so I hope that the cover from an 880 is a straight swap.
780 880 990

User avatar
dsk
Posts: 306
Joined: Thu May 06, 2010 2:42 pm
Location: Caithness

RE: Re: RE: 1968 780 Rebuild (lots of photos)

Post by dsk » Tue Oct 19, 2010 9:09 pm

The pins in the 996 cover pulled out fairly easy with pliers, so if I can work out exactly what size drill to use I should be able to drill new holes in the 780 cover and push them in.

Been at the black stuff again.
Image
Image
Image
Image

These took more work than anything previous. They cleaned up quickly on the underside but the top where all the mud collects was badly pitted and I used a rotary wire brush several times to speed things up.

I took one of the original reductions off tonight and it is in really poor shape. ALL the bearings are completely knackered. The driveshaft just flaps about loose. So I feel very happy to be replacing them.
Image

Wrong colour I know, but I'd rather get them sealed than worry about authenticity.
780 880 990

Post Reply

Who is online

Users browsing this forum: No registered users and 1 guest