Gearbox filler plug seized

[KenMcCulloch]

My Beta 25 TMC40 gearbox filler plug won’t come out. I’ve had the boat since November and want to change the gearbox oil. No evidence of when it was last done but some reasons to suspect maybe not for a while.

I have a fairly chunky adjustable wrench which fits well but the plug will not budge. I tried yesterday after the engine had been running, although not for long enough to get the gearbox really warmed up. I’m not unduly worried about it, there’s enough oil in there and if push comes to shove I can probably change the oil through the dipstick hole, but it would be good to have everything right. How much force might be needed, and would careful use of a heat gun be prudent?

 

[doug748]

It goes into the alloy, a friend of mine stripped his and had a hell of a job fixing it.
If I find mine stuck this winter I may well leave it there.

 

[neil_s]

I tend to agree with doug above - especially since you can use the dip-stick hole. I change the oil in my Bukh through the dip stick hole every year. If you do want to shift the sump plug, don't use an adjustable spanner - get a correctly fitting ring spanner or a socket

 

[paulajayne]

Do not use a adjustable as it will not fully support the nut.

Use correct size socket or ring spanner.

Ring spanner probable best as once fitted tap it on the other end with a hammer gentle to tighten it, then tap to loosen. This may break the seal and get it moving.

 

[RichardS]

I tend to agree with doug above - especially since you can use the dip-stick hole. I change the oil in my Bukh through the dip stick hole every year. If you do want to shift the sump plug, don't use an adjustable spanner - get a correctly fitting ring spanner or a socket

Surely it's the filler plug we're talking about, rather than the sump plug?

I thought most gearboxes were filled, and emptied, through the dipstick hole so I'm not sure why there would be separate filler hole.

If it can be filled and sucked-out through the dipstick I would stick with that until you have the correct spanner.

Richard

 

[Dull Spark]

I have a TMC 40 too. It had only about 200cc of oil. (A cupful only). I last changed the oil by sucking up into a "pipettes" and blowing it into a small bottle of waste. I used the dipstick hole because the quantity was small and access to the drain plug was poor.

Mark up the waste bottle to show when you've got about 170cc. You are unlikely to get all of it out, but I got most.
Good luck.

 

[RobinBirch]

I had the same problem with my Beta 25/TMC40 at its first 25 hours service - a good quality ring spanner shifted it eventually.

 

[simonfraser]

You have used some freeing oil ?
Not in a hurry i guess, put some on every week, i’ve had good results with Kano Kroil

 

[sailorman]

Surely it's the filler plug we're talking about, rather than the sump plug?

I thought most gearboxes were filled, and emptied, through the dipstick hole so I'm not sure why there would be separate filler hole.

If it can be filled and sucked-out through the dipstick I would stick with that until you have the correct spanner.

Richard

My PRM has a drain plug

 

[RichardS]

My PRM has a drain plug

I suspect that virtually every engine ever made has a drain plug ...... but is that relevant to this thread?

Richard

 

[neilf39]

I have the same problem trying to do the 25 hour service. Hitting spanner with a hammer hasn't helped so far. Will use my Pele pump through the dipstick hole. Drain plug inaccessible anyway. I have a small funnel so filling via the dipstick not an issue either.

 

[awol]

Ken, heed the warnings. By all means try a ring spanner or socket, a shifter is not a good idea, but if it is still reluctant to move consider the aggro a stripped thread is going to cause. Sooking the oil out is a solution to the oil change, buggering up the drain plug thread stops you using the donk and probably the boat (though you have enjoyed the parking service of the R*** before!)

 

[sailorman]

I suspect that virtually every engine ever made has a drain plug ...... but is that relevant to this thread?

Richard

Yes as i drain & refill mine

 

[sailorman]

I have the same problem trying to do the 25 hour service. Hitting spanner with a hammer hasn't helped so far. Will use my Pele pump through the dipstick hole. Drain plug inaccessible anyway. I have a small funnel so filling via the dipstick not an issue either.

Are Beta aware of this issue, mebe they need to undo the this bung when assembling the engine & re tighten to an appropriate torque

 

[DownWest]

Had this with a 1GM10 g/box. The filler is also the dipstick, so used a socket and tube on the bar. Serious force applied and it slowly came out. Corrosion between the threads and ally case, caused by the box filling with rainwater and emulsionizing the oïl. But, no corrosion on the gears or bearings. I left the sump plug as it is not easy to get a socket on to and I risked cracking the case.

 

[PhillM]

Same problem with a Beat 14/TMC40 since new. Just use the dip stick hole as already suggested and I use a large syringe to refill.

 

[Dull Spark]

This link to an O&M may be of interest.
http://www.melody-in-blues.org/downloads/Service Manual TMC 40 M.pdf
Good luck.

 

[KenMcCulloch]

Ken, heed the warnings. By all means try a ring spanner or socket, a shifter is not a good idea, but if it is still reluctant to move consider the aggro a stripped thread is going to cause. Sooking the oil out is a solution to the oil change, buggering up the drain plug thread stops you using the donk and probably the boat (though you have enjoyed the parking service of the R*** before!)

Well it’s the filler plug rather than the drain plug so damage to the threads would probably be annoying rather than catastrophic. I have a selection of syringes and small bore tubing previously used for refilling a compass, should do the job.

 

[VicS]

Well it’s the filler plug rather than the drain plug so damage to the threads would probably be annoying rather than catastrophic. I have a selection of syringes and small bore tubing previously used for refilling a compass, should do the job.

Something like this would do the job

 

[DownWest]

Just to add, a friend stripped the thread on his LR Discovery sump. I looked up on the web and found kits to rethread for a larger size with plugs included. Not expensive, even when they had several different sizes in the kit.