Search found 2150 matches

by db2d
Wed Dec 18, 2019 9:15 am
Forum: DBTC Forum
Topic: Reduction unit Special C spanner
Replies: 8
Views: 649

Re: Reduction unit Special C spanner

The C spanner available from DB Parts is an exact replica of the DB service tool. The ring nuts in 780 tractor reductions are usually tight and should not be released without a suitable spanner. New replacement nuts are not available. In addition to the C spanner, two, half inch BSF set bolts three ...
by db2d
Tue Dec 17, 2019 7:13 pm
Forum: DBTC Forum
Topic: Voltage Regulator / Dynamo
Replies: 16
Views: 942

Re: Voltage Regulator / Dynamo

The regulator contacts should be cleaned with a fine carborundum stone or silicon carbide paper.

The cut-out relay contacts should be cleaned with a strip of fine glass paper—never use carborundum stone or emery cloth.
by db2d
Sun Dec 15, 2019 7:16 pm
Forum: DBTC Forum
Topic: Selectamatic 990
Replies: 4
Views: 456

Re: Selectamatic 990

The nut is a locknut so penetrating oil will have very little effect, if any. The area on the shaft where the locknut is located is larger than the lower part. Turn the throttle until it is against the throttle stop and also hold the lever whilst undoing the nut. Heat maybe necessary but a new lockn...
by db2d
Sat Dec 14, 2019 8:59 pm
Forum: DBTC Forum
Topic: DB 990A Implematic Hydraulics Not Working
Replies: 39
Views: 1913

Re: DB 990A Implematic Hydraulics Not Working

It is important that the hydraulic control linkages are correctly adjusted to avoid damaging the pushrod. The spring can be retained with either a circlip or an e-clip but the best option is to drill a hole and use a split pin. Incidentally, without going into details this pushrod assembly can be ch...
by db2d
Fri Dec 13, 2019 10:52 pm
Forum: DBTC Forum
Topic: DB 990A Implematic Hydraulics Not Working
Replies: 39
Views: 1913

Re: DB 990A Implematic Hydraulics Not Working

Briefly—The mechanism inside the housing only comes into play when the sensing cable is attached to the top link or the height control attachment. This mechanism is for the operation of draught control and TCU etc. For auxiliary hydraulic operation the main control lever connects with a small pushro...
by db2d
Thu Dec 12, 2019 7:36 pm
Forum: DBTC Forum
Topic: 3 way valve for 990 implematic
Replies: 4
Views: 364

Re: 3 way valve for 990 implematic

All that is needed to operate the hydraulic cylinder on the snow blower is an inexpensive spool valve, provided you operate the two way valve to provide an oil supply. I have a DB tractor with a hydraulic cylinder on the rear linkage in place of the top link with the setup I have described.
by db2d
Thu Dec 12, 2019 8:44 am
Forum: DBTC Forum
Topic: 3 way valve for 990 implematic
Replies: 4
Views: 364

Re: 3 way valve for 990 implematic

The only advantage in updating to a three way valve is an extra auxiliary connection, the taps would have to be operated individually to divert the oil. I presume the snow blower would have a double action hydraulic cylinder therefore a spool valve would have to be incorporated into the system. On I...
by db2d
Fri Dec 06, 2019 11:40 pm
Forum: DBTC Forum
Topic: DB 990A Implematic Hydraulics Not Working
Replies: 39
Views: 1913

Re: DB 990A Implematic Hydraulics Not Working

Some form of heating may be necessary, or a warm environment to warm the oil, and thaw any water that maybe present.
by db2d
Fri Dec 06, 2019 11:14 pm
Forum: DBTC Forum
Topic: 1965 David Brown 880UE Implematic, how to prime transmission hydraulic pump?
Replies: 111
Views: 5782

Re: 1965 David Brown 880UE Implematic, how to prime transmission hydraulic pump?

1965 880 threads are mostly UNC ( Unified National Course).
by db2d
Fri Dec 06, 2019 11:08 pm
Forum: DBTC Forum
Topic: DB 990A Implematic Hydraulics Not Working
Replies: 39
Views: 1913

Re: DB 990A Implematic Hydraulics Not Working

The easiest method to fill the gearbox with oil is to remove the cover on top of the PTO unit and simply pour it in.
by db2d
Fri Dec 06, 2019 9:45 pm
Forum: DBTC Forum
Topic: 1965 David Brown 880UE Implematic, how to prime transmission hydraulic pump?
Replies: 111
Views: 5782

Re: 1965 David Brown 880UE Implematic, how to prime transmission hydraulic pump?

The threads on DB tractors are predominantly BSF ( British Standard Fine) or Unified ( UNF/UNC ).
The bolts securing the control valve onto the aluminium pump are 5/16 BSF. 1/4 Whitworth spanner size.
by db2d
Fri Dec 06, 2019 2:15 pm
Forum: DBTC Forum
Topic: 880A Selectamatic information request
Replies: 18
Views: 2456

Re: 880A Selectamatic information request

Cropmasters and 30C series one tractors rear lights were positioned either side of the double seat with a provision for illuminating the registration plate. The single armoured cable was secured with small P shaped metal clips about 1/2” wide and 1/8” screws and nuts. The cable for the plough lamp s...
by db2d
Fri Dec 06, 2019 8:55 am
Forum: DBTC Forum
Topic: 880A Selectamatic information request
Replies: 18
Views: 2456

Re: 880A Selectamatic information request

Replacement mudguards do not have holes for the wiring, these holes have to be drilled. 30C series one tractors did not have rear lights on the mudguards other than the plough lamp. Tubing was not used but armoured cable secured with clips, was.
by db2d
Thu Dec 05, 2019 10:44 pm
Forum: DBTC Forum
Topic: DB 990A Implematic Hydraulics Not Working
Replies: 39
Views: 1913

Re: DB 990A Implematic Hydraulics Not Working

Is the lever on the right hand side of the ramshaft out towards the mudguard and down ? Remove the cover and check the operation of the trip mechanism by operating the lever by lifting the lever until it connects with the operating pivot and then up further to trip the linkage. Do this a few times t...
by db2d
Thu Dec 05, 2019 8:16 am
Forum: DBTC Forum
Topic: DB 990A Implematic Hydraulics Not Working
Replies: 39
Views: 1913

Re: DB 990A Implematic Hydraulics Not Working

Extending the cable with the control lever in the lowering position will move a spool valve and the snow blower should lower. You can do this without fitting the cable onto the top link.