Technical Oil pressure

[1970Norway]

Changed the main bearing on flywheel side last night.
Used Ricambio -0,40 mm bearing.
Changed clutch with the same time.

Started up today, but the oil warning lamp will noth disapear
What can have gone wrong?
Too big bearing??

the car is a 1970 Fiat 500 L in Norway

 

[the hobbler]

Changed the main bearing on flywheel side last night.
Used Ricambio -0,40 mm bearing.
Changed clutch with the same time.

Started up today, but the oil warning lamp will noth disapear
What can have gone wrong?
Too big bearing??

the car is a 1970 Fiat 500 L in Norway

First of all, check that the oil-pressure sender electrical conection is good. How much of the engine did you strip when fitting the new bearing? Did you measure the crankshaft prior to fitting the bearing so that the bearing matches the crank journal? It seems slightly unusual that only one end of the crankshaft is so worn that it needs a big'oversize' bearing and the other end does not. Whenever I have an engine stripped, I always repack the oil-pump with "Petroleum jelly" (aka--vaseline) NOT grease. Did you have the complete crank out of the engine---have you put the 'spacer-washer' back in the correct way (the chamfer on the spacer to face the crank journal)

 

[1970Norway]

First of all, check that the oil-pressure sender electrical conection is good. How much of the engine did you strip when fitting the new bearing? Did you measure the crankshaft prior to fitting the bearing so that the bearing matches the crank journal? It seems slightly unusual that only one end of the crankshaft is so worn that it needs a big'oversize' bearing and the other end does not. Whenever I have an engine stripped, I always repack the oil-pump with "Petroleum jelly" (aka--vaseline) NOT grease. Did you have the complete crank out of the engine---have you put the 'spacer-washer' back in the correct way (the chamfer on the spacer to face the crank journal)

 

[1970Norway]

Took out the engine, because of clutch chudder and oil leak.
As you see in the picture, the old bearing had and damage, so i replaced it with a new.
I need too check the oil pressure first.
What is a ok pressure?

 

[1970Norway]

This is the old bearing, can someone help me too identify the part number?
Looks like 41.0102.6.000400

 

[Bounding Bambino]

Your best bet is to measure the crankshaft diameter and then we can recommend a proper clearance and bearing size.
With that said here are the factory part numbers and their under size.

These come from the 110F parts manual. Fiat does have # revisions as time went on.
4108755 - 0.0mm
4108756 -0.2mm
4108757 -0.4mm
4108758 -0.6mm
4108759 -0.8mm
4108760 -1.0mm

The end seal has a # - 40000160

ill see if i have a newer manual.

Also with a fresh engine, and cold 25w50 oil. oil pressure is around 55-60psi cold. and will drop as oil warms. Folks will chime in with the pressure setting on the switch. I cant remember its "low" pressure setting.

 

[1970Norway]

Took out the oilsensor today, but no oil comes out when the engine is running.

Engine out again, but things looks normal too me!

Measure 53,5 on the crankshaft , and the bearing should be 53,6
Not so easy too have a good measurement.

 

[bugsymike]

Not trying to suck eggs, but when engine rebuilt , the oil pickup tube or what ever your engine uses is in the oil, not bent,split,blocked missing altogther. Over time I have seen all of the above!!!

 

[the hobbler]

Not trying to suck eggs, but when engine rebuilt , the oil pickup tube or what ever your engine uses is in the oil, not bent,split,blocked missing altogther. Over time I have seen all of the above!!!

The 'low-oil pressure' light comes on when the oil pressure drops below between 8.5 and 14 psi. The 'book of words' says that it is OK for the 'low-oil-pressure' light flickers when the engine is idling (hot) as long as it goes out as soon as the engine is revved above idle speed.

 

[bugsymike]

No oil when engine running and sensor removed.... Not good

 

[1970Norway]

Im not shure!
If I don’t find anything wrong with the bearing, maybe it could be the oil pickup tupe
The strange is, that the oilpressure was fine and normal before i took out the engine.
Maybe the pickup tupe got damage when I was lifting the engine around in my garage

 

[bugsymike]

Im not shure!
If I don’t find anything wrong with the bearing, maybe it could be the oil pickup tupe
The strange is, that the oilpressure was fine and normal before i took out the engine.
Maybe the pickup tupe got damage when I was lifting the engine around in my garage

Didn't disturb the oil pump at all?

 

[1970Norway]

No, didn’t toutch the oilpump or oiltube

 

[bugsymike]

No, didn’t toutch the oilpump or oiltube

Assuming new bearing didn't block an oil way and nothing was disturbed that drives the oil pump, plus no damage to oil pick up as I mentioned earlier, can you spin the engine over with the plugs out and maybe prime the system by pumping clean oil in via the oil switch hole.
I know you shouldn't have to do any of this, but it will help minimise further chance of damage rather than running engine.

 

[1970Norway]

Assuming new bearing didn't block an oil way and nothing was disturbed that drives the oil pump, plus no damage to oil pick up as I mentioned earlier, can you spin the engine over with the plugs out and maybe prime the system by pumping clean oil in via the oil switch hole.
I know you shouldn't have to do any of this, but it will help minimise further chance of damage rather than running engine.

Took down the oilsump and tupe today, and it looks fine.
Next step is the oilpump i think, because when i totated the engine several times for hand… no oil was coming out the line too the rear bearing

 

[bugsymike]

Took down the oilsump and tupe today, and it looks fine.
Next step is the oilpump i think, because when i totated the engine several times for hand… no oil was coming out the line too the rear bearing

Strange pump working before strip down, nothing got in to block it or a new gasket with missing holes?
The sump gasket can't go the other way around, blocking return from rear main?
Can't see from the photo is there a flange gasket between the oil pickup and the engine block, I can only see it looks to have a locating spigot, I assume the flange is true/flat?

 

[the hobbler]

Strange pump working before strip down, nothing got in to block it or a new gasket with missing holes?
The sump gasket can't go the other way around, blocking return from rear main?
Can't see from the photo is there a flange gasket between the oil pickup and the engine block, I can only see it looks to have a locating spigot, I assume the flange is true/flat?

There is no gasket on the 500 and 126 between the oil pick-up tube and the crankcase---however, there is a thick rubbere '0' ring that goes between the pick-up tube flange and the crankcase (the tube potrudes very slightly past the crankcase side of the pick-up tube flange to locate the '0' ring). When you changed the rear bearing, did you only remove the clutch, flywheel and back (flywheel end) bearing?

 

[1970Norway]

There is no gasket on the 500 and 126 between the oil pick-up tube and the crankcase---however, there is a thick rubbere '0' ring that goes between the pick-up tube flange and the crankcase (the tube potrudes very slightly past the crankcase side of the pick-up tube flange to locate the '0' ring). When you changed the rear bearing, did you only remove the clutch, flywheel and back (flywheel end) bearing?

Took down the oilsump today, and the ool pich up tube.
Checked the oilpump, filled it with new oil and mount together with new gasket and so on.
New 20-50 mineral oil, and prefilled the hole too oil level swith.
Started up, and now the oilpressure seems normal.
Looks like there has been som air in the system for oilpump

 

[Bounding Bambino]

Glad you solved it.
Odd that it was very difficult to prime. Sometime pumps that have some internal scoring, or wear can be hard to get the initial prime.

 

[bugsymike]

Took down the oilsump today, and the ool pich up tube.
Checked the oilpump, filled it with new oil and mount together with new gasket and so on.
New 20-50 mineral oil, and prefilled the hole too oil level swith.
Started up, and now the oilpressure seems normal.
Looks like there has been som air in the system for oilpump

Fingers crossed all good.