Gear box not good

[Creel]

Hi that checked the oil in the hydraulic gear box see pic . engine runs when gear liver is in the ahead position but stops dead when I put it in to reverse . checked oil and found what's in the pic this was nearly up to the top of the dip stick any one got any ideas as I can not afford a reconditioned one . I will put fresh oil in the box and try it again this is not all the oil that came out

[Alan de Enfield]

That is emulsified oil (water and oil mixed) and 'beaten' to a thickish consistency.

 

Somehow getting water into your gearbox - the problem will not be solved by replacing the oil.

 

Work is needed to be done to the mechanicals - maybe just a cheap 'seal' maybe more severe, but, it will only get worse by not attending to it.

 

Very few broken mechanical things mend themselves with further usage.

[Creel]

That is emulsified oil (water and oil mixed) and 'beaten' to a thickish consistency.

 

Somehow getting water into your gearbox - the problem will not be solved by replacing the oil.

 

Work is needed to be done to the mechanicals - maybe just a cheap 'seal' maybe more severe, but, it will only get worse by not attending to it.

 

Very few broken mechanical things mend themselves with further usage.

thanks for the reply boat has not been on the water for 3 years no leaks from the box so I think the boat has been full of water at some time and the water has got past the dip stick looks like I will have to get the box out and strip it down

[David Mack]

It might just need adjusting (apart from replacing the oil and sorting out the water ingress). If it stops dead in reverse it might just be that due to incorrect adjustment you are engaging forward and reverse gears at once. What model gearbox is it?

[bizzard]

If this is a Lister LH150 box there are two reasons why it stalls the engine when trying reverse. One is loss of hydraulic pressure causing the forward gear cone clutch not to disengage when moving the lever towards neutral and reverse and trying to engage both forward and reverse at the same time. The second is the forward cone clutch has jambed (stuck) in the hub and won't pull out. A good flush out with a 50/50 mix of paraffin and oil and running the engine whilst trying to disengage it and then drain and fill with fresh Hypoy oil, often fixes that. I doubt if its the adjustment as the forward gear clutch loses its play as the lining wears not increase the free play. Of course it could be more serious like bust hydraulic seals or badly worn down to the rivets cone clutch lining and jambing in the groove they've made in the hub.. Judging by the jollop what was in the box the cone clutch has probably stuck in the hub with a mixture of oil, water, rust and fibre lining dust, I'd try the flushing and fresh oil first.

[Creel]

If this is a Lister LH150 box there are two reasons why it stalls the engine when trying reverse. One is loss of hydraulic pressure causing the forward gear cone clutch not to disengage when moving the lever towards neutral and reverse and trying to engage both forward and reverse at the same time. The second is the forward cone clutch has jambed (stuck) in the hub and won't pull out. A good flush out with a 50/50 mix of paraffin and oil and running the engine whilst trying to disengage it and then drain and fill with fresh Hypoy oil, often fixes that. I doubt if its the adjustment as the forward gear clutch loses its play as the lining wears not increase the free play. Of course it could be more serious like bust hydraulic seals or badly worn down to the rivets cone clutch lining and jambing in the groove they've made in the hub.. Judging by the jollop what was in the box the cone clutch has probably stuck in the hub with a mixture of oil, water, rust and fibre lining dust, I'd try the flushing and fresh oil first.

Thanks that was my first thought to flush it will give it a try

[nicknorman]

I don't know about your specific installation but lots of gearboxes have a heat exchanger with the engine coolant, so it could be that the heat exchanger is leaking and allowing coolant water into the gearbox oil.

[Mrs Tawny Owl]

LH150's don't usually have oil coolers so I suspect that what the OP said about the boat being full of water at some time and it getting in past the dipstick might be more likely.

 

Richard does a lot of work on these so feel free to ask questions, and I've just had a batch of reverse bands relined to go with the relined cones I had a while ago, just in case the linings of either have been destroyed by the gloop.

 

Sue

Also these gearboxes are designed to fail in forward, you need oil pressure to pull them out of forward into neutral or reverse so if that gloop doesn't allow enough oil pressure to be generated it'll stay in forward. Cheapest and easiest first option is to flush out and try with new oil as has been suggested.

 

In case you didn't know, for the Lister gearboxes you need EP80 / 90 gear oil.

 

Sue

[Creel]

LH150's don't usually have oil coolers so I suspect that what the OP said about the boat being full of water at some time and it getting in past the dipstick might be more likely.

 

Richard does a lot of work on these so feel free to ask questions, and I've just had a batch of reverse bands relined to go with the relined cones I had a while ago, just in case the linings of either have been destroyed by the gloop.

 

Sue

Also these gearboxes are designed to fail in forward, you need oil pressure to pull them out of forward into neutral or reverse so if that gloop doesn't allow enough oil pressure to be generated it'll stay in forward. Cheapest and easiest first option is to flush out and try with new oil as has been suggested.

 

In case you didn't know, for the Lister gearboxes you need EP80 / 90 gear oil.

 

Sue

Thanks will try the flush will get some EP80/90 how much will I need

[Alan de Enfield]

Apart from speculation as to the gearbox model being LH150 - has the OP actually confirmed the make and model ?

[Creel]

Apart from speculation as to the gearbox model being LH150 - has the OP actually confirmed the make and model ?

Yes it is a LH150 gear box hydraulic

[Iain_S]

Agree with Bizzard, but not sure how that much water would get past the dip stick in normal use.

Has the gearbox been under water or partially submerged at some time?

Also, the LH150s I've seen have a seperate reduction box. What's the oil like in that?

[Creel]

Agree with Bizzard, but not sure how that much water would get past the dip stick in normal use.

Has the gearbox been under water or partially submerged at some time?

Also, the LH150s I've seen have a seperate reduction box. What's the oil like in that?

I don't know all I know is the boat has not been on the water for 3 years the reduction box oil is clean all so the automatic float switch was not turning the bilge pump on so the gear box could have been under water Edited April 19, 2016 by Creel

[Creel]

Tried a flush no luck will have to remove box and strip it down then rebuild it . Where will I get gasket from and seals presuming I will need them

[DHutch]

I don't know about your specific installation but lots of gearboxes have a heat exchanger with the engine coolant, so it could be that the heat exchanger is leaking and allowing coolant water into the gearbox oil.

 

That was my first thought.

LH150's don't usually have oil coolers so I suspect that what the OP said about the boat being full of water at some time and it getting in past the dipstick might be more likely.

 

But I would happy bow to the above advice!

 

 

Daniel

[RLWP]

Tried a flush no luck will have to remove box and strip it down then rebuild it . Where will I get gasket from and seals presuming I will need them

Sue (Mrs Tawny Owl) can help. I know we have the gaskets, seals and forward cone clutches, I'm not sure about brake bands at the moment

 

Richard

[Creel]

Sue (Mrs Tawny Owl) can help. I know we have the gaskets, seals and forward cone clutches, I'm not sure about brake bands at the moment

Richard

thank Richard when I get the box out and striped I will know what I will need then I will get intouch with sue

[Creel]

Got my gear box ready to lift out hope to get it out next weekend will post pics of the rebuilding of it hopefully it won't be to bad I will know what gaskets and seals I will need when I get it striped

Neil

[Tony Brooks]

LH150's don't usually have oil coolers so I suspect that what the OP said about the boat being full of water at some time and it getting in past the dipstick might be more likely.

 

snip

 

One reason they do not need oil coolers while other hydraulic boxes do is because they do not pressurise the oil when in ahead, only in reverse and neutral, so the oil simply does not get as hot.

 

 

[Creel]

Just a quick up date I have the gearbox out it is down at my pals work shop hope to get it striped this Saturday