Hello, while i have my LT77 out and about to rebuild does anybody know of any mods that can be done to the box to improve it in any way?
Thanks.
Mods to an LT77???
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davemgb
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- Joined: Sat Nov 18, 2006 5:55 pm
- Location: Just north of watford
Fitting later bearings to an early box is not easy since they are larger in diameter, you would need the bearing housings enlarged and a later input shaft which is larger.
I've had several failures over the years due to the oil pump failing and since the later boxes - LT77S and R380 - have filters I found a way to fit one in. This will make sense if you know the normal assembly sequence.
The filter is FRC7855 and is fitted onto the pump pickup pipe of R380 boxes. in the LT77 boxes this pipe has a flattened end to try and act as a strainer. This pipe needs to be shortened by about 25 mm and returned to its former round shape with a suitable mandrel. You then drill out the hole in the filter to fit the pipe but keep it a firm fit and not loose, additionally you need to remove some of the clip section on the filter since it will be pushed as far onto the pickup pipe as possible when the gearbox is assembled. Do a dummy assembly of the gear cluster into the centre plate then fit the fifth gear componentry and the rear housing including oil pump and pickup pipe. Now push the filter onto the pickup pipe and push it right up against the centre plate and you will find that the filter projects into the gasket line, a 3mm deep recess cut into the main casing will clear this without compromising the gasket performance.
This might not seem clear written here but if you do a dummy build before you modify anything it will become clear. If I can find the photos I thought I took I'll add them to this post.
Dave
I've had several failures over the years due to the oil pump failing and since the later boxes - LT77S and R380 - have filters I found a way to fit one in. This will make sense if you know the normal assembly sequence.
The filter is FRC7855 and is fitted onto the pump pickup pipe of R380 boxes. in the LT77 boxes this pipe has a flattened end to try and act as a strainer. This pipe needs to be shortened by about 25 mm and returned to its former round shape with a suitable mandrel. You then drill out the hole in the filter to fit the pipe but keep it a firm fit and not loose, additionally you need to remove some of the clip section on the filter since it will be pushed as far onto the pickup pipe as possible when the gearbox is assembled. Do a dummy assembly of the gear cluster into the centre plate then fit the fifth gear componentry and the rear housing including oil pump and pickup pipe. Now push the filter onto the pickup pipe and push it right up against the centre plate and you will find that the filter projects into the gasket line, a 3mm deep recess cut into the main casing will clear this without compromising the gasket performance.
This might not seem clear written here but if you do a dummy build before you modify anything it will become clear. If I can find the photos I thought I took I'll add them to this post.
Dave
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davemgb
- Helpful or Confused
- Posts: 143
- Joined: Sat Nov 18, 2006 5:55 pm
- Location: Just north of watford
Paul,
What do you mean by a better change?
Is the gearshift vague?
Are you finding the synchro does not have time to work when you shift. The most common reason for this is worn synchro cones and the mating surfaces on the gears, changing the cones only is not a fix. Selector forks will wear rapidly if you dont use the right oil in the box.
Dave
What do you mean by a better change?
Is the gearshift vague?
Are you finding the synchro does not have time to work when you shift. The most common reason for this is worn synchro cones and the mating surfaces on the gears, changing the cones only is not a fix. Selector forks will wear rapidly if you dont use the right oil in the box.
Dave
-JC.