930 Scavenge Pump on 83 SC

sigchuck · 09-28-2019, 10:31 AM

Hi gents, I’ve looked through quite a few old posts on the topic of using a 930 scavenge pump with SC cams, but I think most of them are directed at SC cams being fit in 930 engines.

I think if I understand correctly, with my late year SC, I should be able to pop the freeze plug off the front left cam and insert two 5mm roll pins that will drive the scavenge pump. Aside from modifications to the engine tin and oil lines, would I need to do anything else to make this work? Would my engine have mounting provisions for the pump? I think a spacer/adapter may be needed for earlier SC cams, but I think with mine I could avoid this issue, correct?

Any insight you guys could offer would be very much appreciated!! Thanks!

Uwon · Uwon's Garage

On my 3.2 converted to a 3.4 turbo with SC cams, I have air pump housing with the pulley inside as a spacer to which the roll pins are screwed into. The pump is then attached directly to the housing face plate.

Hope this helps.
Good luck.
Johan

spuggy · 09-29-2019, 09:17 AM

Quote:

Originally Posted by Uwon

On my 3.2 converted to a 3.4 turbo with SC cams, I have air pump housing with the pulley inside as a spacer to which the roll pins are screwed into. The pump is then attached directly to the housing face plate.

Interesting; on my 930, I have no air pump housing - the (Clewett) scavenge pump screws directly to the housing (with 3 M6 cap screws) and sits about where the air pump is in your picture.

OP:

pretty sure 930 tin is readily available/relatively cheap (I looked it up before I modified mine)
might want to fit a CHT sensor while you're in there
not sure genuine SC cams have the roll pin holes?

spuggy · 10-03-2019, 05:07 PM

Quote:

Originally Posted by spuggy

not sure genuine SC cams have the roll pin holes?[/LIST]

Apparently SC cams usually do have the holes. Found the thread where billjam wrote up lots of great info with pics while looking for something else: Confused on sc cams???

scottrx7tt · 10-04-2019, 04:21 AM

Many have had great luck gravity draining the oil to the sump including me. Before doing the 930 scavenge pump, you may want to atleast try gravity draining.

sigchuck · 10-04-2019, 07:40 AM

Thanks, Scott! I appreciate all the posts you've made on the gravity drain and my plan was to try the Setrab sump fitting you recommended first, but I did see a factory scavenge pump for a price that wasn't too outrageous. Of course that's just the pump, not the lines, 930 oil tank, etc.

Hopefully I have the same experience as you. I'll be using a K27 (which I think is what you have as well). Any interference issues with the line and headers/exhaust? I'll be using Fabspeed headers and I'm a little concerned about routing the line without contacting the headers. I was also curious as to what type of line you used. It seems like it would be pretty simple to make one using braided steel over rubber with AN fittings, but wondering if the hose needs any special ratings due to oil temp (notwithstanding the number of rubber hoses in the oil system already). Also, are you still able to use the sump plate as a jacking point?

TurboKraft · 10-08-2019, 07:22 AM

Quote:

Originally Posted by sigchuck

Also, are you still able to use the sump plate as a jacking point?

The sump plate was *never* a jacking point.

sigchuck · 10-08-2019, 07:53 AM

Not even with the rolled up newspaper jack pad adapter (extra points if its a German language edition)?

I am the proud new owner of a QuickJack, so I'll forego this method in the future. Still trying to figure out placement points though as the pinch welds are out due to AC lines.

spuggy · 10-08-2019, 09:36 AM

Quote:

Originally Posted by sigchuck

I am the proud new owner of a QuickJack, so I'll forego this method in the future. Still trying to figure out placement points though as the pinch welds are out due to AC lines.

Given that Quickjack ramps have to be parallel, the jack points are probably a lot more inboard than you would think.

If you bought the SLX (for maximum versatility with other vehicles), there's really only one satisfactory way to get it to work on a 911.. Otherwise it'll foul the front wheel, on a narrow body.

Two sets of blocks at the rear seems to work best, otherwise the floorpan rests on the ramps, I use a full-height block and a low-profile slotted hockey puck-style at the front. And I've put labels on the ramps to lines up with the factory jack receiver - for quick alignment fore-and-aft...

sigchuck · 10-08-2019, 09:49 AM

Spuggy, thanks for the advice! I've definitely looked at moving the ramps inboard, but I haven't been able to find the right combination to not directly impact the floorboards (which I'm worried would dent them). I don't have the SLX though.

spuggy · 10-16-2019, 08:40 AM

Quote:

Originally Posted by sigchuck

Spuggy, thanks for the advice! I've definitely looked at moving the ramps inboard, but I haven't been able to find the right combination to not directly impact the floorboards (which I'm worried would dent them). I don't have the SLX though.

Moving the AC lines is one bolt. Just sayin'.

I found that the ramps contact the floorpan if you don't use two blocks at the rear. The doors will also be harder to shut, showing the body is flexing. if you use two blocks, there's much less, perhaps no, contact (and the doors are easier to shut). I also use 2 blocks at the front, but one is a hockey-puck style (shallower).

I stack the blocks at the extreme front of the engine-end recess for them, and line up the slots to protect the seam weld (the '77 doesn't have any fitting points for the jacking pucks the later cars do).

The 5000SLX is long enough that the front blocks line up further forward on the seam. They end up inboard of the wheel, ahead of the floor pan.

From this thread: Looking for feedback from QuickJack users

This picture (not me) shows quite clearly how inboard the ramps need to be to clear the wheels and stay parallel:

And this diagram shows the jack points someone annotated to show what they use; with a 5000, you need to go further forward on the front seam than the indicated corner - I'm almost at the B points; maybe I could make it if I oriented the rear blocks further back in the recess... - oooh, there's a thought...:

I still set up jack stands on general principle, but frankly have pretty much zero concerns getting under the car with the QJ so long as the ramps are locked - although I do also make a point of unplugging the control box and disconnecting the hydraulic lines...