Thread: 3.9 cam lift

Originally Posted by blackbuttdisco

I had a look at the Triumph/Roverwebsite that was on Phillpas post. Yank bloke claimd Rover "forgot " to put a hole in the distributor drive gear for the oil to get out. Now when you consider how many Rover V8s are happily motoring almost everywhere in the world, does this bloke know what he is talking about. He appears to claim he knows more than a very big engineering and development company, or is he just another septic tank?

On carby engines the "missing" hole is a notch in the fuel pump cam's keyway, I assume the efi engine has a notch in its spacer too. The oil feed is via a hole in the cam from the front journal. I have seen drive gear failure twice from incorrectly fitted spacers.

No, the oil feed to the distributor drive is via the space between the keyway and the spacer on the cam nose and then via a groove in the distributor drive, which I guess overlaps the spacer so lets the oil out onto the drive.

I have just read the manual and realise that I have put the distributor drive sprocket in back to front and now I have to dismantle it and correct the error. Damn,Damn, damn!!!!

So this thread was useful to me.

Attachment 34302

Here is a pdf of the page.
Regards Philip A

If you want a new cam Ring Dean Tighe and tell him what you want it to do he will have a grind.

do a google for Tighe cams brisbane.

Originally Posted by PhilipA

No, the oil feed to the distributor drive is via the space between the keyway and the spacer on the cam nose and then via a groove in the distributor drive, which I guess overlaps the spacer so lets the oil out onto the drive.

I have just read the manual and realise that I have put the distributor drive sprocket in back to front and now I have to dismantle it and correct the error. Damn,Damn, damn!!!!

So this thread was useful to me.

Correct, the keyway is the channel for the oil after it has passed through the hole in the cam's thrust collar, the pic is not that clear but the hole is just above the keyway.



I have just confirmed that the carby fuel pump cam has the notch, and the 3.5EFI dissy drive gear has an annular groove to spray oil from behind the gear. The inner ring of the groove is a few thou proud of the rest of the gear, leaving a gap all the way around. Theoretically it should work either way around, the washer is flat and would leave a similar gap. Actually the washer is a tad too small so the oil feed would be bigger. Would it starve the front cam journal of pressure? Possibly not. Certainly it would spray oil around the timing case.

So critical ignorance might lead you to use an EFI spacer with a carby drive gear, leaving you with a "missing" hole. Interesting, the things you find when you look.

So what do you reckon?
Leave it as is? or pull the front apart again to flip the drive gear.

My thought is that the oil may not splash back towards the chain which I believe is the intention of having the groove on the back of the gear.

I should have read the manual when I was unsure which way around. I just checked whether the gears ran the right way for the dizzy gear and was to tired to think logically whether it was the same either way which it obviously is.


Regards Philip A

Originally Posted by PhilipA

So what do you reckon?
Leave it as is? or pull the front apart again to flip the drive gear.

My thought is that the oil may not splash back towards the chain which I believe is the intention of having the groove on the back of the gear.

I should have read the manual when I was unsure which way around. I just checked whether the gears ran the right way for the dizzy gear and was to tired to think logically whether it was the same either way which it obviously is.


Regards Philip A

The dissy driven gear will spray oil back onto the chain. Either way the notch/groove is 1 to 1.5 inches in front of the chain line. And the oil drainage is towards the bottom sprocket. I would just monitor chain stretch for a while, have a new chain on hand when or if it gets sloppy.

Go to TR8/Tr7/Rover forum near the bottom of PhillipA's post and open it. If you go to the discussion section for Rover V8 and open it, then open "Distributor drive gear" and also open "Yep, it was the distributor drive gear". Read these 2 and tell me that this bloke knows more than Rover do.