J type overdrive

[Jonathan_bell]

I have a j type overdrive on my TR6, which was reluctant to engage, but eventually would work. So I had to replace the clutch over the winter so took the opportunity to check the hydraulics, when I removed the cover plate and took the metal filter out it was clear this had not been removed for some time, small metal particles, I also removed the pressure relief assembly and again noticed many small metallic particles. As the unit was working before I thought that I might be able to get away with a clean out, fingers crossed. So now the new clutch is in and replaced the box, unfortunately the overdrive will not engage any more. I have checked all the obvious electrical issues, I have removed the solenoid and can see the piston actuating when the switch is operated. So now the dilemma! Where did the metal particles come from? Gearbox ? Or Overdrive? . There is no obvious vibration or noise coming from the box, but do I risk bolting a new overdrive unit to it with possible more issue to come. I understand the tr6 gearbox is fairly robust, is there a common culprit in the gearbox that I can rule out? Interestingly when I took the gearbox drain plug out I had the typical amount of magnetic particle on the plug, but the debri in the overdrive did not appear to be magnetic! Possibly chromium?

 

Any comments welcome

[AlanG]

FWIW I recently fitted a TR6 J type that I inherited with my non OD 4A. As GB and O/D were an unknown quantity I stripped and rebuilt the GB with the only damage found being a broken thrust washer. The OD pressure filter revealed a considerable amount of metallic particles although no large lumps of metal. I decided to get the OD checked by OD Spares in Rugby. This proved the OD to being working well and the considered opinion was that the metallic particles were from the GB over a considerable time and not an indication of a problem with either units. I think the pressure filter rarely got cleaned in bygone times. GB and OD have now done 3000mls. with no problems.

Alan.

[pfenlon]

I have a j type overdrive on my TR6, which was reluctant to engage, but eventually would work. So I had to replace the clutch over the winter so took the opportunity to check the hydraulics, when I removed the cover plate and took the metal filter out it was clear this had not been removed for some time, small metal particles, I also removed the pressure relief assembly and again noticed many small metallic particles. As the unit was working before I thought that I might be able to get away with a clean out, fingers crossed. So now the new clutch is in and replaced the box, unfortunately the overdrive will not engage any more. I have checked all the obvious electrical issues, I have removed the solenoid and can see the piston actuating when the switch is operated. So now the dilemma! Where did the metal particles come from? Gearbox ? Or Overdrive? . There is no obvious vibration or noise coming from the box, but do I risk bolting a new overdrive unit to it with possible more issue to come. I understand the tr6 gearbox is fairly robust, is there a common culprit in the gearbox that I can rule out? Interestingly when I took the gearbox drain plug out I had the typical amount of magnetic particle on the plug, but the debri in the overdrive did not appear to be magnetic! Possibly chromium?

 

Any comments welcome

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