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My Major is nearly complete and I was just made aware of a problem that scares the crap out of me. I'd like your opinions please.
It seems that some previous owner or mechanic crossthreaded or otherwise screwed up the threads for the transmission dip stick. They repaired that problem by installing a Helicoil. My mechanic had some difficulty removing the dip stick because the helicoil had broken and was spinning in the hole. As I understand the story now, the helicoil apparently cracked a thread at approximately the same depth as the dip stick plug "max reach" meaning that some portion of the coil remains in the hole and (hopefully) the remaining piece was removed, intact. The dip stick plug cannot reach those threads and was therefore replaced with a longer bolt to seal the box.
Here's the fear...how can I verify that no smaller portion of the threaded helicoil has fallen in to the gearbox. I know I have to replace the 3rd gear synchro soon, but if there is a chance that a piece of coil is in that box, the car should not move, period. Just that little piece can change the job from a $5000 gearbox rebuild to a $25,000 gearbox replacement.
Are helicoils made of ferrous materials? Will the magnetic drain plug hold any possible piece away from the gears (assuming if gets captured)? Is oil flow dramatic in those boxes?
Next question...once the gearbox is disassembled (for the synchro job), what is the "proper" way to fix these threads? It seems to me that installing a small metallic insert is just stupid.
It seems that some previous owner or mechanic crossthreaded or otherwise screwed up the threads for the transmission dip stick. They repaired that problem by installing a Helicoil. My mechanic had some difficulty removing the dip stick because the helicoil had broken and was spinning in the hole. As I understand the story now, the helicoil apparently cracked a thread at approximately the same depth as the dip stick plug "max reach" meaning that some portion of the coil remains in the hole and (hopefully) the remaining piece was removed, intact. The dip stick plug cannot reach those threads and was therefore replaced with a longer bolt to seal the box.
Here's the fear...how can I verify that no smaller portion of the threaded helicoil has fallen in to the gearbox. I know I have to replace the 3rd gear synchro soon, but if there is a chance that a piece of coil is in that box, the car should not move, period. Just that little piece can change the job from a $5000 gearbox rebuild to a $25,000 gearbox replacement.
Are helicoils made of ferrous materials? Will the magnetic drain plug hold any possible piece away from the gears (assuming if gets captured)? Is oil flow dramatic in those boxes?
Next question...once the gearbox is disassembled (for the synchro job), what is the "proper" way to fix these threads? It seems to me that installing a small metallic insert is just stupid.