Project Money Pit !

It should produce oil pressure spinning on the starter. May take 10-20 seconds first time
 
This isn’t a running bike - yet.

Still got some work to do before I attempt to fire it.

I have only spun it over on the starter.

The R80 engine I built last year built oil pressure really quickly - just on the starter - but this one hasn’t.

I was considering removing the oil pressure switch (again) and pumping fresh oil in there to kind of ‘back bleed’ it to give the oil pump a chance to lift some oil from the sump.
Yep understood. You should get those pressures spinning it up on the starter with plugs out. And it should hold above 15 psi for about 20 seconds after you stop spinning it.
 
The battery is on charge overnight - though it was pretty healthy.

Will give it another spin tomorrow.

I’ll be braver and spin it for longer 😉
 
Did you put plenty of oil on the pump rotors when you fitted them?
If you fitted them dry ,the pump won’t draw oil up from the sump.
You also run the risk of doing some serious damage to the pump/ housing

I put assembly lube on the pump inner and outer rotors before fitting the cover.

Gave it a good spin this morning and the oil pressure warning light didn’t go out and there’s no oil behind the switch.

No oil at the rockers either.

I’m pretty resigned to pulling the gearbox, flywheel etc and having a look at the oil pump. 1. To be sure the inner is turning and 2. Refill it with assembly lube.

Is packing the pump with petroleum jelly a thing ? Recall doing this to a Rover V8 that wouldn’t pump oil (many moons ago when a much younger me built a Triumph TR8 replica)

Having got this far I don’t want to risk damaging anything.
 
This is the right side cylinder head with what I had in the way of valve gear. You will see there is no exhaust rocker - just the pillars so I could torque the head down.

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I pulled those off and removed the mounting buttons in the head. Pic shows one button removed - 3 to go..

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And then refitting monolever rockers

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Re-torqued everything and set the clearances.

Next weekend will be a strip down of the rear of the bike and flywheel removal so I can access the oil pump
 
I put assembly lube on the pump inner and outer rotors before fitting the cover.

Gave it a good spin this morning and the oil pressure warning light didn’t go out and there’s no oil behind the switch.

No oil at the rockers either.

I’m pretty resigned to pulling the gearbox, flywheel etc and having a look at the oil pump. 1. To be sure the inner is turning and 2. Refill it with assembly lube.

Is packing the pump with petroleum jelly a thing ? Recall doing this to a Rover V8 that wouldn’t pump oil (many moons ago when a much younger me built a Triumph TR8 replica)

Having got this far I don’t want to risk damaging anything.
Is it possible to measure the actual oil pressure using a gauge - just interested .
 
Is it possible to measure the actual oil pressure using a gauge - just interested .

I believe you can put a fitting (and connect to a pressure gauge) in the hole where the oil pressure switch lives.

I’m pretty sure I have zero oil pressure to measure at the moment 🙁
 
A thought occurred to me ,
Last year , another chap had the same issue with no oil pressure,
Turns out,he’d mixed up the rear crank boss o ring with the oil pump cover o ring.
The thicker o ring caused excessive clearance on the side of the pump so it couldn’t draw oil up from the sump.
 
A thought occurred to me ,
Last year , another chap had the same issue with no oil pressure,
Turns out,he’d mixed up the rear crank boss o ring with the oil pump cover o ring.
The thicker o ring caused excessive clearance on the side of the pump so it couldn’t draw oil up from the sump.

Thanks Mike.

Aren’t those ‘o’ rings different colours ?

Hopefully I didn’t do that.

I’m going to crack into it this weekend. I’m going to strip the back end of the bike off, remove the flywheel and have a close look at the oil pump.

Fingers crossed I don’t find any damage to the pump rotors or the housing 🤞

What do you think about the petroleum jelly idea ? Packing the pump to help it draw ?
 
The oil pump housing o ring is normally red.
I’ve never needed to do more than a good wetting with oil .
Give everything a good degrease and take some pics
I presume also that it has the correct oil pickup/ strainer for the sump that’s fitted?
 
I flicked back through the photographs I took during the engine refresh and I don’t have one of the oil strainer / pickup.

You’ve given me an idea though.

I do have a boroscope for my iPhone.
I can put this in the dipstick hole and try to confirm the pickup is submerged in oil.

I did find a post clean up photo of the rear main seal and oil pump cover.

IMG_2153.jpeg
 
Got home an hour earlier than usual today and the weather being so lovely decided to start to trouble shoot this.

The boroscope down the oil filler hole was partially successful in that it confirmed the oil pickup was submerged. It’s only a cheap one and it was tricky to get in an angle but I’m reasonably confident.

Time to strip this thing

IMG_2693.jpegIMG_2694.jpeg

So bit the bullet and stripped everything off the back of the bike to make access easier.

Reasonably quick to strip but I know it will take me much longer to reassemble everything.
 
And the smoking gun ?

Oil pump removed..

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Look at that ‘o’ ring 😲

I think it’s the wrong one.

It’s black and quite thick - not the much slimmer red one 🙁

It was still wet and sticky in there with assembly lube so I think I got away without causing any catastrophic damage.

That’s all I had time for this evening but I’m hoping we’ve found the problem.

@mikeyboy - as they say in Australia - good call 🫡
 
Being a mono it’s got the separate flywheel carrier thing and I left that in situ for the moment.

I’m pretty sure I’ve got a red oil pump ‘o’ ring in my spare parts drawer.

Will fit this first just to see if it is then able to pump oil.

If it does, I will pull the flywheel (again) & carrier thing to see if I got them transposed.

Thinking about it, aren’t the flywheel and clutch carrier bolts single use ?

Replacing them all and ordering the correct ‘o’ ring will delay me putting it back together for sure.

My fingers are firmly crossed that it can be saved
 
I’d reuse the flywheel and clutch bolts in this instance ,
The engine hasn’t been run.
I would however replace the clutch bolt washers.
The clutch dosnt need to be fitted to spin the motor to check if it has pressure..
I’d be 99% certain you’ve solved the issue
 


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