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Nov 18, 2016 8:27 am
Nov 18, 2016 8:27 am
Subject: Re: LG 45 Engine
It's a sorry story really. It was a perfectly good sump but I wanted to modify the chassis lubrication system so that the lubrication pump took clean oil from the jacking oil tank rather than dirty oil from the sump. This was pretty straightforward but needed the oil path from the sump blanking off. On the Meadows engine you drain oil from the sump via the same port as the chassis lube take-off so I needed a new sump drain.
The welder was confident he could weld in a threaded drain boss but he clearly didn't know what he was doing and had too much localised heat so the casting split. He chased the crack and made it worse and worse. He even tried welding in a small alloy plate to cover it up but it was a mess. By the time I found out about it it had gone too far for me to live with so I bought a new one from David Ayre.
I suspect years of oil in the casting and poor quality porous metal made welding tricky but think that if the whole casting had been placed in a furnace to bring it up to temperature, and then returned to the furnace after welding and allowed to cool down really slowly, it would have probably been fine.
I think that now it needs cutting out and a repair plate screwing in place from the inside but it will never look pretty - not that you can see it unless you're underneath. It could even be lined with fibreglass (GRP).
There you have it...
The chassis lubrication mod works a treat by the way. The sumps drain boss was eventually bolted through the new sump instead of welded. I couldn't risk that again!
Quote by bill:
David, thanks very much for that and I will bear it in mind. Whereabouts is the damage on the sump ? Was it just bad welding or was it the impurities in the metal which was the problem ? I understand that the Meadows casting material was very poor during the 1930s for both engine and gearbox. Is it possible to effect an engineering rather than a welding solution ?
Thanks again.
It's a sorry story really. It was a perfectly good sump but I wanted to modify the chassis lubrication system so that the lubrication pump took clean oil from the jacking oil tank rather than dirty oil from the sump. This was pretty straightforward but needed the oil path from the sump blanking off. On the Meadows engine you drain oil from the sump via the same port as the chassis lube take-off so I needed a new sump drain.
The welder was confident he could weld in a threaded drain boss but he clearly didn't know what he was doing and had too much localised heat so the casting split. He chased the crack and made it worse and worse. He even tried welding in a small alloy plate to cover it up but it was a mess. By the time I found out about it it had gone too far for me to live with so I bought a new one from David Ayre.
I suspect years of oil in the casting and poor quality porous metal made welding tricky but think that if the whole casting had been placed in a furnace to bring it up to temperature, and then returned to the furnace after welding and allowed to cool down really slowly, it would have probably been fine.
I think that now it needs cutting out and a repair plate screwing in place from the inside but it will never look pretty - not that you can see it unless you're underneath. It could even be lined with fibreglass (GRP).
There you have it...
The chassis lubrication mod works a treat by the way. The sumps drain boss was eventually bolted through the new sump instead of welded. I couldn't risk that again!