Crossflow oil pressure after rebuild

[viva_65]

Hello wonder if anyone has had a similar problem to me

Rebuilt my 1600 crossflow mains shells rings
First ran showed good oil pressure light went out (independent systems)
500 miles running it in, pulling into the car park noticed oil light just came on had a quick glance at the oil pressure and nothing,
Changed oil pump to a old one I know was good, still no pressure
Changed the sump and pick up pipe (no good)
Removed the adapter block I had for the oil pressure sender so it was just the original light sender in the block still no good!! I the took that sender out blew down with airline and light went out 99% sure it's not switches!

So I then striped the engine again mains shells have little to no wear!! I didn't touch the cam bearings and as I said was perfect for 500miles was at low rpm when the light came on!

There is more where on the roocker shaft around where the rockers sit, but not enough to loose oil pressure I wouldn't imagine

Only thing I can think is I've got a cracked oil way, is there common areas on the crossflow engines to crack because I can't physically see anywhere, or has anyone had anything similar?

Can you get a block pressure tested?

Any help will be greatly appreciated as I am tottaly stumped cheers

[rodney]

ive had this on a cvh and a r5gtt engine , are the shells the correct size?? has the crank ever had a regrind?,.

[viva_65]

Crank has been re ground and has been bored out I've double checked I've fitted the correct shells the ones I removed wasn't that bad of nick

[v8ian]

What Oil are you using?? Did you use silicon mastic on the rebuild? correct filter?

[viva_65]

I've just looked at the cam bearings again and it looks like the oil way is Beeing half covered? The oil way runs between the camshaft bearing and 1 of the mains, it doesn't look like it's rotated and I wouldn't know how it could but could this be the problem? I would imagine this would increase the oil pressure

Cheers

[viva_65]

Used classic motor oil think 5w 40, I have wondered I did use silicone on the sump gasket there wasn't that much access when I just removed the sump but guess it wouldn't take allot would it! Yes oil filter were definately right it was giving good pressures for 500 miles

[v8ian]

5/40w is wrong!!!!, should be 20/50, crossflows are a oil volume rather than oil pressure engine, so pressure is not as essential as you would think, I don't thing 20 psi hot at tick over for a fresh engine on 20/50 is unusual on a fresh engine.
I don't think synthetic or semi syn is good for a new, old style engine either, it glazes the bores

[viva_65]

Just went out and checked it is Morris classic oil 20w 50 I used, after I put the new sump and pick up pipe on I changed the oil so wouldn't be oil deteriated to much

[viva_65]

Ow it is semi-synthetic

[v8ian]

That wont immediately affect the bores, its mainly because the older style engines don't run nikasil or chrome bores, so you don't really need to bed rings in, on the x flow, first the rings are a lot thicker and apply less pressure on the bores and with the superior lubrication of semi syn, it prevents the rings bedding in against the cast bores.
I know you said you changed the pickup pipe and sump, Not knowing what pickup pipe you are using, is there any chance the pickup is blocked by sitting too close to the sump, that can be the case wit the saucer type filters on the bottom of the Pickup, and if the sump gets pushed up on a speed bump or something it can close the gap between the sump and pipe, I always used to weld a 6mm nut to the edge of the pick-up just to prevent this,
Is it worth taking the cover off the pump and inspecting the gears?possibly check the clearences

[colnerov]

Oil pressure relief valve stuck or sticking open?

[v8ian]

Another thought or two, Thrust bearing undersize/dropped out/not fitted did you put a smear of something around the top of the pickup pipe when fitting, Can you fit a temporary capillary oil gauge even if you just tape it to the top of the scuttle so you can see it and go for a drive? . Pessimistic this time, crank badly machined, or block not thoroughly cleaned and blocked oil way,

[vitesseefi]

Have you changed the oil filter again since the trouble started? If the filter has become blocked or seriously obstructed and does not have an internal relief valve, most of the oil will be recirculating through the pump relief valve and oil pressure will be low to nil....

Nick

[viva_65]

I took the sump pick up pipe oil pump and the filter off of a 1300 crossflow I was running last year in it so I know that's all sweet, when I rebuilt it I put a new oil pump on it I did check the cover, didn't check any clearances tho, I didn't put any oil or anything when I put the pick up pipe in! But again was sweet for 500 miles

[viva_65]

When I done the rebuild every oil way was blown through with clean oil, new thrust bearings were fitted std ones came out so that's what I put in,

[baggabones]

Oil light and gauge sharing the same sender? easy and cheap swap

[jules1200]

Long time since I did a xflow, but from memory, the main shells have a drilled & a non drilled, are they right way round ?

[viva_65]

There was a aluminium block Whitch allowed you to use both original sensor for light and the new sender to recieve oil pressure, both lost at the same time, I even removed the Ali block and just had the oringinal sensor in and still no pressure

Mains were definately correct yes there are 2 holes in there with only 1 Beeing used as a oil way

Think the only option I got is to clean re assemble the bottom end, crank it and see if I get oil through the top of the block, if not it's scrap