Have a shovel with low oil pressure. Everything looks good but...
Want to install a new oil pump but all require the hole to be drilled for the new style oil pump. Are there any alternatives? What is the hole for?
Thanks,
Dave

 

Ain't a Shovelhead in the world that has oil pressure...Unless something is Wrong!!!
Is it Cycling Oil OK?

 

Ain't a Shovelhead in the world that has oil pressure...Unless something is Wrong!!!
Is it Cycling Oil OK?


Oil between head is barely dribbling out. Checked against my bike and its shooting out. The bike sounds great at startup but sounds like rocker arms are dry while running. We just rebuilt motor after rear cylinder cracked at the base.

 

the -68 first original oil pump had a couple of special issue, the second one was the pin that stays the 2 oil pump idler gears would become loose < plenty of reasons why it did that - than what would happen is the oil pressure side, ended up bleading off into the return side of the gearing that does not have a pressure relief valve and that lowers the pressure even more -

than add that too the fact that the pinion shaft that carries the oil to the lower unit does it as a side oiler not an end oiler like everything from the cone motor in 73 up to the end of the evo in 99 -

so now we get to why the oil hole is drilled - being a side oiler the lower unit was secondary to oil pressure not primary, And the blead off is much greater than the later pump so what we have is a lean top end oil. to fix that the the hole goes from the pumps main pressure to the feed hole in the cover for the lower unit

now too make this clear - the screen in the block just above the oil pump - with the old pump is low pressure - with the drilled hole the new pump feeds Hi pressure to the screen via the top end / and splits to the lower unit all is feed Hi pressure - hence the reason for valve seals and smoaking after an oil pump conversion

hope that helps - some one else might have a different take on this but after doing close to a 1000 lower units this is what i know to be true - jz

 

Try you HD dealership they still may be able to order you the OEM pump. I got one for my 72 (same pump) not that long ago.

 

I have been having better luck with OE ...
Certainly Lately.