Rebuilt my bottom end everything new had it running in the car and it started knocking so took it out again replaced all bearing shells greased them up with graphogen grease changed the oil pump again incase it was that to be sure. So i got it running again today and it was all going well sounded nice and quiet then the dreaded light came on but it isnt knocking, ive changed the oil pressure switch to see if it was that and no luck there, any ideas? Really peeing me off now as its costing me time and money

 

Get an oil pressure gauge, what oil are you using?

And are you measuring anything when you build the engine?

Rob.

 

I bought an oil pressure gauge just wsiting for it to be delivered so ill wire that in before i fire it up again. Using 10/40. I had the crank reground to accept .25 bearings which the engineering company supplied for me.

 

Okay,


Unfortunately i think the engine will need a strip down (sorry!), you are going to have to find the cause of low oil pressure. Whether that be too large a clearance between journals or bearings, something funny with the oil pump, even camshaft journal clearance.

It might be worth taking your crank back and getting them to re measure it for you, i can give you the minimum diameter.

Sorry mate, feel for you

Rob,

 

Ok. Suppose i shall have to make a start again tomorrow night. Pretty sure it isnt the oil pump as ive swapped it for a known working one about 500 miles old. Real stressfull times as id love to have the thing out and about soon.

 

Just take your time mate, measure the crank up properly.

Get some plastigauge to check your clearances. if all bearing clearances are fine and nothing silly is wrong, i would suspect the oil pump, but get the gauge on and make sure your lights not dodgy!

Rob,

 

Cheers good idea. What should it measure?

 

hi im havein the same prob oil light comes on wen the car gets up to temp then struggles to idle and slowly dies.my ellec oil pressure gauge is reading 1.5bar on idle wen hot i put a mechanical one on and thats reading 1 bar on idle.it started to nock on the bottom so engine out and to the buiders.and this is the 2nd engine its done it to

 

Check the strainer in the sump as I had one that got instant gasket in it and that purred until warm then the light would come on.

 

IS 10W40 not a bit thick to use in a freshly rebiult engine?

 

what rob an oranoco have said pretty much nails it mate, i would suspect oil pump or too much bearing clearance, is it the same shell thats been knocked out each time? also id check the oil gallerys are all clear (block and crank)

thanx

liam

 

Cheers ive done that now, it did have a little bit of gasket sealant stuck right in the middle of it and it hasn't come on since, but i didnt run it for very long only about 5 minutes.

Tried two oil pumps now, as soon as it started knocking i took the engine out replaced all the shells, greased them up and it hasnt knocked since.

Also ive got an oil pressure gauge to be fitted, ive got the sender unit, will i need an adaptor tee piece of some sort? As the oil pressure switch and turbo oil feed come off the tee already on the block.

Cheers.