Case 1594 4wd power shift with cab.

[RBinDevon]

Hi,

A bit of help or pointer would be greatly welcomed.

The tractor has stuck in low range on the mechanical box. I suspect that the selector finger(?) has somehow jumped out of the selector fork.

Though with this design I am surprised. Am I missing anything?

If it has jumped out I intend to undo the the linkage, lift it up to re-engage the selector finger into the selector fork.

 

[Netherfield]

Absolutely not unusual, wear in DB selectors as been going on since Adam was a lad. Although there is also a roll pin that breaks as well.

 

[Netherfield]

http://partstore.caseih.com/us/parts-search.html#epc::mr60175ar1048179

Part No 20 and 25 are the pins No 18 wears

http://partstore.caseih.com/us/parts-search.html#epc::mr60175ar1048249

Part No 30 fits in to 18 above and wears, any of the various roll pins on this page also known to break.

 

[RBinDevon]

Thanks guys. Will take the top off and have a go.

 

[marcusthehat]

Being an experienced=exasperated DB1490 owner, I have difficulty understanding how David Brown, who/which firm I understood to be "big" into gearboxes/transmissions, were the firm that appears to have come up with the poorest/weakest gear selection arrangement.
mth

 

[Netherfield]

Being an experienced=exasperated DB1490 owner, I have difficulty understanding how David Brown, who/which firm I understood to be "big" into gearboxes/transmissions, were the firm that appears to have come up with the poorest/weakest gear selection arrangement.
mth

Truck gearboxes, were very highly rated, ship and submarine gearboxes for navies all over the world gears for power stations including nuclear, but of course from two different factories with different agendas.

Made worse by the fact the problems stem back from the 50s, they never decided to fix it in later models.

 

[Ray996]

Hi,

A bit of help or pointer would be greatly welcomed.

The tractor has stuck in low range on the mechanical box. I suspect that the selector finger(?) has somehow jumped out of the selector fork.

Though with this design I am surprised. Am I missing anything?

If it has jumped out I intend to undo the the linkage, lift it up to re-engage the selector finger into the selector fork.

Fiddly fkr of a job .my 1490 did same take top of selector on gearbox ,get mirror and torch to look in to selector and lever it back into neutral,assuming that's the problem !sorted my tractor anyway.

 

[RBinDevon]

Fiddly fkr of a job .my 1490 did same take top of selector on gearbox ,get mirror and torch to look in to selector and lever it back into neutral,assuming that's the problem !sorted my tractor anyway.

That's the plan now. The room under the cab floor is restricted, as you say it looks to be a bu@@er of a job.

I was wondering if the cause could be the wear allowing the ball of the selector pin to slip between the two selector forks
Had thought that if the ball was thickened slightly it would not be able to slip though again.

Just hope that it is not the roll pin broken.

 

[Ray996]

That's the plan now. The room under the cab floor is restricted, as you say it looks to be a bu@@er of a job.

I was wondering if the cause could be the wear allowing the ball of the selector pin to slip between the two selector forks
Had thought that if the ball was thickened slightly it would not be able to slip though again.

Just hope that it is not the roll pin broken.

Old age wear and tear ,took me bout an hour to do ,had mechanics telescopic mirror for the job ,not easy wedging yourself under cab,

 

[REStracTORATION]

Cut floor out make it bolt bolt back in weld the selector ball up a tad

 

[Ray996]

Cut floor out make it bolt bolt back in weld the selector ball up a tad

Another option lndeed ! Bit brutal tho!

 

[RBinDevon]

Another option lndeed ! Bit brutal tho!

True, but am old, bad back and have short arms, so may go through the floor.

 

[Ray996]

True, but am old, bad back and have short arms, so may go through the floor.

Seat out gets ya straight in,bad back and big gut on me but I managed job fine

 

[Netherfield]

I have to admit I've never done a 94 series only the 1490 and 1690, that was a mirror job, I was led to believe by @John 1594 that the floor came out on the 94s, but I dont know for sure.
Another failing for DB , the same cab, on the Leyland/Marshall floor was removable.

 

[RBinDevon]

I have to admit I've never done a 94 series only the 1490 and 1690, that was a mirror job, I was led to believe by @John 1594 that the floor came out on the 94s, but I dont know for sure.
Another failing for DB , the same cab, on the Leyland/Marshall floor was removable.

I won't have time to start until the weekend. I hope you are right that the floor comes out, though on viewing from the underside I doubt it.

However many thanks for your input.

 

[RBinDevon]

No, the floor under the seat on the 1594 does not unbolt, we cut it out.
Tomorrow the investigations really start. Got a little push!!!!!!! Probably well deserved!!!!!!!

 

[Marshall 100]

I have to admit I've never done a 94 series only the 1490 and 1690, that was a mirror job, I was led to believe by @John 1594 that the floor came out on the 94s, but I dont know for sure.
Another failing for DB , the same cab, on the Leyland/Marshall floor was removable.

Yes,on Leyland you have removable floor panels and normally no need to enter gearbox/selectors and on DB opposite way...

 

[RBinDevon]

All done.
The selector pin could not slide between the two selector forks. It just does not locate deep enough into the selector forks. So when at the end of travel, when you select a range, if you push had enough (I wasn't driving) the pin can slip out of the selector forks. BAD DESIGN.
However all working now and advice given!!! Be gentle.

Thanks for your help, one and all.