There were also some stainless ones made that were supposed to work harden but didn't and should be avoided. Cheers, Stu.
OP: Oil Pump Oil Pump
- Thread starter davidd
- Start date
I purchased 2 oil pumps recently. On one it was almost impossible to turn the pump by hand and the other turned “quite freely”. I haven’t measured them, but certainly a difference in clearance.
Prior to removing a pump sleeve, it would be worth checking to see if the outer race of the small roller has walked inward. I’ver never tried it, but thinking that with the inner race removed, you could sneak in there with a puller and pull the outer race home and out of the way (assisted with some heat). Looking at my supply of knackered oil pump sleeves tells me it’s fairly common for the race to move inward. If it is in the way, the reamer isn’t going to like that, nor will the new pump sleeve. The new pumps have an aluminum end cap instead of the original style bronze ones, so may not take the same amount of abuse during removal. Thinking it would be good to check the outer race before the pump housing is removed and better to use a puller than a slide hammer so the threaded rod doesn’t rip out of the pump housing.
Prior to removing a pump sleeve, it would be worth checking to see if the outer race of the small roller has walked inward. I’ver never tried it, but thinking that with the inner race removed, you could sneak in there with a puller and pull the outer race home and out of the way (assisted with some heat). Looking at my supply of knackered oil pump sleeves tells me it’s fairly common for the race to move inward. If it is in the way, the reamer isn’t going to like that, nor will the new pump sleeve. The new pumps have an aluminum end cap instead of the original style bronze ones, so may not take the same amount of abuse during removal. Thinking it would be good to check the outer race before the pump housing is removed and better to use a puller than a slide hammer so the threaded rod doesn’t rip out of the pump housing.
If the pump sleeve is very tight you are better off to make a long threaded puller and slowly wind it out, yes the 5/16" thread in the alloy end cap will pull out. Most often when you install the outer small main bearing race when the case cools, the race will shrink too much and the inner race will be too tight. I have to take the case half to my local engine reco shop where they hone the race larger to allow the inner to fit nicely..........This is very common, and many engines I have pulled apart, this bearing is too tight.........so much so that it makes it difficult to remove the crank assembly. Another issue which can go unnoticed is the timing cover screw just forward of the oil pump locating screw, if this is replaced with the common Allan head cap screws, and over tightened, it can bottom at the very thin end of its hole, this pushes directly against the side of the pump sleeve and will easily distort it. On my friends Norvin race engine this had happened, and it totally destroyed the oil pump, the drive worm, and due to no oil circulation, destroyed the big end as well....... He sent me though some pics of it, and you could see how the problem started...........a bit nasty. The gear teeth on the plunger looked like an apple core with the middle chewed away and the outer left behind.
Another option is Wellseal. I seem to remember a suggestion by Peter Bell regarding Loctite that is drawn in by capillarity but I forgot the grade. Cheers, Stu.
When i see a ol or new casing, always do lapp the thing to 25,40mm, with full lenght metal hone and time-saver grinding stuff, no reamer as they are bit to big to handle, so chatter starts.....
Maybe one with a pilot or a blunt one will work, than again, whats its diameter......
than I undermachine the pump sleeve by just 0,05 or so:
only where no sealing is neccecary , specially at the open part,
as thrust there will only warp it to the moon, hammering starts, as does the cursing and silly Threads here...
So no problems with bearings etc.
On a double pump i file out the round holes to square, to ease the oilflow. as with the narrow "pressure exit"
put it in hot, ready, most problems start with the little screw to controll the pump OP36, but when one puts in a long screw 5/16 one can turn it bit right hand to position the sleve.
i cant say this often ennough, in the end its so simple......
Maybe one with a pilot or a blunt one will work, than again, whats its diameter......
than I undermachine the pump sleeve by just 0,05 or so:
only where no sealing is neccecary , specially at the open part,
as thrust there will only warp it to the moon, hammering starts, as does the cursing and silly Threads here...
So no problems with bearings etc.
On a double pump i file out the round holes to square, to ease the oilflow. as with the narrow "pressure exit"
put it in hot, ready, most problems start with the little screw to controll the pump OP36, but when one puts in a long screw 5/16 one can turn it bit right hand to position the sleve.
i cant say this often ennough, in the end its so simple......
Vincent, it is only simple because you know how to do it, and you also have the knowledge and equipment, for me a hammer is a sophisticated piece of machinery.