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750 oil flow

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UK Pete:
with my rocker box off and engine and oil tank full of oil, i decided to check the oil flow was getting up to the top end
it was getting up there alright pumping through the cam bearings, and squirting out the four holes directed at the cam lobes, but to my horror i see that no oil passage to the rocker shafts, just a small hole on the top of each rocker in the hope that oil splashing around will work its way in there
anyway after having my engine running for about 5 mins on off, maximum of 3000 revs i took off the back tappet covers only to see them virtually dry, certainly not swmming in oil, and the inside of the tappet cap bone dry
does this mean that you have to rev the granny out the thing in the hope that a splash of oil gets to the shafts? if so what a shit design
or am i missing something
Pete

Yoshi823:
Hi Peter. Have you checked that the small oil jets that are in the cam carriers are free to squirt oil onto the cam lobes & rockers? I seem to remember that once the oil came up through the oil restrictors just under the cam carriers, the oil is not in any way directed onto the rocker shafts...they rely purely on the oil that sits in the 'pool' of oil that is within the carrier once it's bolted down onto the cylinder head. Hence it's the splash from this that lubricates the lobes & rocker bearings. But this oil pool is supplied by the drillings within the cam carriers. Maybe a quick squirt with some contact cleaner will tell if the drillings are clear. Don't forget to make sure that the 'O' rings around the oil restrictors are new when you bolt the cam carriers back down.

Spitfire:
Hi Pete, the fact that you are getting oil to both sides of your cam is good news, on each cam tower there are individual oil feeds to each cam bearing plus 4 spray feeds all pointing the same way. If you are not getting enought oil then it could be down to your pump, pump screen, or oil filter.
I have only looked into the front of the cam box through one of the tappet covers with the engine running and there was lots of oil spraying around. In fact I seem to recall that there were problems with the cam box running flooded (overheating ?)

Cheers

Den

Yoshi823:
Hi Den. There were differant drillings in the cylinder heads between the F1 & the F2 heads. From what I remember there were fewer drain holes for the oil to flow away back down to the sump on the F2 head...presumably so as to keep the oil in the head for longer. The sump pans on the F2 are also slightly deeper between K/F1 & F2 sump pans, presumably to increase the total capacity.

the-chauffeur:

Pete

There are no oiling holes in the cam towers that feed directly onto the shafts.  The feeds are the oilways you've seen spraying, and one each under the ends and centres cam journals.  The shafts rely on the holes on the top of the towers to collect spray - which isn't exactly an ideal method given the thrashing the oil pumps sometimes get.

It's probably a bit late now, but have you seen HondaMan's post on the shaft differences, top end oiling and modifying the towers?


 

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