Oil pump failure

[JOOLZ]

I just got back from a short ride (20miles) and when I pulled up at home I noticed a squeak from the top end that was not there before, so I thought I would investigate.  I checked the oil level that was fine, then I loosened the head oil pipe and there was no oil coming out. I removed the oil filter and kicked the engine over and only a very small amount of oil is being pumped in.
I have now removed the clutch case to get access to the pump. The first thing I noticed was the O ring on the pump seems to have melted around the edges. I think I am going to have to rebuild the pump with new O rings and check all the tolerances.
Im also very worried about the top end, that cam is a 1 off so I hope thats not damaged.
I only saw 1 small metal fragment on the drain plug magnet so fingers crossed I haven't ruined the engine

[JOOLZ]

Just lifted the cam cover, plenty of oil still inside, the cam and rockers are in good condition, so thats one thing less to worry about.  All I need to do is investigate the oil pump problems.

Is it possible to get an air lock in the pump after the oil system has been primed ?.......If it is then this could be the cause of all the ruined heads that I have heard about from XR XL and XBR owners, even ones that are well maintained and the oil checked regularly.

I measured the oil taken out of the engine and it was spot on, I have spun the pump by hand and it seems to be flowing ok, but I will change the O rings and see if that helps.

Anyone with any ideas on whats happened ? as its all a bit of a mystery at the moment

[Propellor]

Here's hoping you got away lightly.

The melted oil pump o rings lead one to think perhaps did the oil pump run dry for a period? Surely not the dreaded air lock we are discussing on another thread?

I need to get my head around just what is going on with this design. And I thought boxers were quirky!

Does a boxer count as a thumper? Bit tenuous. They thump pretty well with the right "silencers" fitted. Pushing me luck, I know.

[guest1640]

Where does the orings come from? Genuine or aftermarket. Some cheaper brands have a much lower melt point than OEM. Caterpillar earth moving do a high temp series for internal galleries on transmissions. Coloured yellow... Might be worth a look. Did you ride it hard the time before this...?might just need a good brand of oring with a modified motor like yours...

[Propellor]

Where does the orings come from? Genuine or aftermarket. Some cheaper brands have a much lower melt point than OEM. Caterpillar earth moving do a high temp series for internal galleries on transmissions. Coloured yellow... Might be worth a look. Did you ride it hard the time before this...?might just need a good brand of oring with a modified motor like yours...

Viton may be the material you are referring to. It is also resistant to more chemicals too. The default o ring and oilseal material is nitrile as far as I know. Although gawd knows what the "economy" brands are made out of. Chewing gum by the way they perform. Rubbish, as you say. Nitrile is good for around 120 deg C I think. Not sure about Viton. Around 150, maybe 180 deg C? Then there are silicon o rings....

[JOOLZ]

I have examined the O rings, and I recon I was sold some cheap rubber compound, I have got a selection of decent silicone O rings now and I will be using teflon tape around the locating dowels as well.  I am also examining the crankshaft oil seal that sits in the clutch cover, as if this has worn then the oil would spill off the crankshaft end and return to the sump without circulating, this would show as low flow through the filter and head oil pipe

[Steve Lake]

silly question I know...what engine is this ...?

[JOOLZ]

XBR 500

[guest1640]

What did you find Joolz.?on yr crank.
If yr in an area with a tractor dealer. John Deere tractor dealers  do a good selection of nitrile and usually sell one offs over the counter...
I'm interested where this goes as there's a bit of thread over oil supply..
Good luck...

[guest1640]

Oh and just out of interest. Do you run an oil cooler???

[johnr]

does the engine have a strainer or filter, have you checked that its not clogged.

[JOOLZ]

I checked the oil strainer, that was clear.  The oil cooler was fine with plenty of oil in it.  I have rebuilt the pump now with the new seals, and I have added an extra seal on the end of the crank to keep any leakage to an absolute minimum from the oil seal that is fitted to the clutch cover. I just have to refit the pipes now, refill with oil and give it a ride. I also replaced the rocker cover bolts with some more titanium.

[JOOLZ]

Took the bike out today just a short trip to the petrol station, everything is fine the oil is now flowing again and im back on the road

[tj63]

I bet that's a relief. It sounded like it could have been expensive.

Trevor

[tommy]

glad to hear that joolz