B40 oil pump returning?

Started by chaz, 17 Oct, 2021, 18:22

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chaz

1965 B40 rebuild
Ive had the pipe off the feed side of the oil pipe union under the engine. The oil seems to be being sucked down but has not appeared yet at the rockers. The engine has not been run yet but I would have expected turning the crank by hand that something may have appeared by now.
the pump was primed on build, and removing the sump plate around 3 litres has come out of the bottom,I cant get the return pipe off either end due to access clearance. Should I still wait or is there likely to be a problem? new hoses and rocker feed pipe.

Colin SS90

Hi
Three litres of oil in the sump seems to be a lot as when I drain my sump I get about 150cc, so you may have a  scavange problem which is preventing oil being returned to the oil tank.
When you say that you are turning the Crank by hand I assume this is by using the kickstart, whilst doing this you should see oil returning to the oil tank if you continually turn the  Crank.
I used the kickstart to turn my rebuilt engine over continually prior to starting it and saw oil going through the clear plastic rocker feed joining pipe.
Colin
1964 SS90

chaz

turning the crank on the rotor by hand, and Ive got black hoses so it does not help.
easier to use the crank rotor nut to turn over on the ramp as the motor is still on the tight side and cant get leg up 4 ft to kick it over.
its up there sorting the wiring, timing, oil etc ,still has to come down to sort leaking fork leg.

cdsdorset

If it is wet sumping that much it is probably leaking around the pump shaft ( you can retro fit an o ring) does it wet sump the same amount if parked at TDC?

chaz

the motor has been built for a while , and left for the frame to be returned, Ive rebuilt a couple since so cant remember much about it.
not sure about the position it leaks as Ive only removed the sump today, only spend an hour or so on it each week but will have  a look next weekend.
think I might struggle with it and fit a length of clear hose just to check before pulling the covers back off again.

Colin SS90

If you take the spark plug out you should be able to use the kickstart by hand giving you faster rotation. When turning rotor were you turning anticlockwise ?
Have you got the feed and return oil pipes correctly orientated under the motor?
To check for wet sumping just leave the sump off and see if any oil collects in a container placed underneath the motor.
1964 SS90

Colin SS90

Oil pipes cross over under the motor, feed from oil tank is nearside and return to oil tank and rocker feed is offside.
While the sump is off use a piece of stuff wire up the oil pump scavenge tube to make sure the non return ball valve isn't stuck which would stop oil return.
Hope this helps with solving the problem.
1964 SS90

chaz

Colin, as mentioned in a previous thread. The motor is tight and wont turn over on the kickstart with plug removed by hand. its better since rechecking valve clearances and primary chain tension, its a new chain.
turning the crank over , the oil does drop through the correct pipes.

chaz

just a question, how much clearance should there be betwen the sump plate and frame rail?
had a quick look this morning and the plate wont come off, with the 4 studs in place the plate hangs up on the front right stud, the bottom frame bolt is fairly loose at the moment, its as if the frame is bent in or the engine too far to the right, but no spacers needed during assembly that I can remember. Im tempted to try to jack the frame over to remove the plate.

Colin SS90

My sump can easily be removed. See attached photo which shows sump then speedo cable then frame tube.
1964 SS90

Colin SS90

Just noticed an alloy spacer on bottom engine bolt (at left edge of photo), but engine location is governed by front and rear engine mounts.
1964 SS90

chaz

thanks for the picture, explains a lot.
will have to re check but my frame rail is partially covering the plate.  will have another look at the weekend,

AdrianS

It does take a while to get oil to the rockers.
I ran up and down my road with the plug out and the engine in gear to try and get oil to the top of the engine. Must have run half a mile before oil appeared!
You can also start the engine and stick a finger inside the oil tank and try and block off the return feed to force oil to the top of the engine.
Finally I would be concerned that your return side is not working. Has the return pipe from the sump become jammed? The flow from the return side is greater than the feed side so you shouldn't collect a sump full of oil when turning the engine over. My engine was rebuilt 5 years ago and if I leave it for 3 months without starting, the sump remains empty apart from what has drained down from within the engine.

chaz

Todays weekly update:
covered up the sump plate again, tbh there wasnt an egg cupfull in the bowl today.
there are no spacers on the bottom engine/frame mount just cases to frame both sides.
no way is it going to start yet, engine is still tight to kick over, will do but not very free have to explore deeper hence not being able to turn by hand on the ramp., have had a bang or two out so timing nearly there.
as for the sumping, it would have had new ball and spring, has pipe assembly cleaned, new hoses but due to confines, its hard to get hoses off and sump plate wont come off so cant push anything up to check scavenge ball,although I would have cleaned it out.

Colin SS90

Regarding engine tight to turn over.
My rebuilt SS90 engine was quite easy to turn over after final assembly, but it took a lot of trial assemblies to get the crank end float correct by changing crank shims and the gearbox mainshaft and layshaft end float correct by changing thrust washers. All end floats kept changing when the casings were torqued up, frustrating, but got them right eventually.
I would check for free rotation of the engine and gearbox individually by either releasing the clutch using a cable tie to hold the lever, or taking the pressure plate off. This would let you rotate both assemblies to check for any tightness.
My engine rebuild was rebore, piston, rings, valves,  big end, small end, main bearings, primary chain, gearbox bearings, camshaft bearings, so everything that rotated was new and quite tight,but turned freely.
1964 SS90