Hi Guys,
Been assembling a bottom end with bits from minispares and when I’ve just tried to fit the pump I noticed the face or the pump doesn’t meet the face of the block. Upon measuring the pump shaft it is 15mm to the pump face and the cam is 12mm from the bottom of the slot to the block face. Now theres no gasket that’ll fix this so whats going on? Has either the pump or the cam been machined wrong and what should I do to fix it?
Cheers
Tim
Turns out its more like 6mm difference. I took the end plate of the pump off and pushed the body home and the pump rotor to the bottom of the cam slot and the rotor sits about 6mm higher than the body
Suggests the cam is not correctly installed, when fitted the cam should sit fairly deep into the hole at the oil pump end. Have you fitted the timing plate, gears and chain ?
What size is the engine???
1275 blocks are about 1/4" longer than a small bore. Cams are all the same length so… Oil pumps for small bore’s and big bore’s take up this difference by having different length shafts.
If you’re trying to fit this combo to a 1275 though and you’re having this issue then something is not sitting right…
As above - I bet it’s a small bore engine and you have a 1275 ‘long shaft’ pump…
> As above - I bet it’s a small bore engine and you have a 1275 ‘long shaft’ pump…
Its a 1300 out of a Morris 1300 so definitely not a small bore, as for the cam being in the wrong place I’ve got the end plate with gasket, and the pulley on. The cam end float is correct and the crank and cam pulleys are aligned when using a straight edge and feeler blades. If the cam was that far out I wouldn’t be able to get a chain on and its all timed up.
I am assuming at this stage that the keyway in the cam is for a small bore engine although it seems strange as the 286 is described as more of a large bore cam
I’m thinking of pressing the pump shaft out and facing the back end to remove the extra length and then reassembling. Does this sound alright? I can’t see why it wouldn’t work
So I rung Minispares and the girl didn’t understand what I was talking about and put me through to an answer phone which is rather awkward when I live in New Zealand. Instead of butchering the pump could I just make up a spacer? I figured the original pump is spider drive and has a really short spline which is where things have gone wrong so any votes for the spacer?
> What size is the engine???
1275 blocks are about 1/4" longer than a small bore. Cams are all the same length so… Oil pumps for small bore’s and big bore’s take up this difference by having different length shafts.
If you’re trying to fit this combo to a 1275 though and you’re having this issue then something is not sitting right…
Not being funny or anything… but
If the blocks were different sizes then there would be gearboxes for 998’s and gearboxes for 1275’s
