|In August of 2000 I bought a Bugpack
oil pump that takes a normal, screw-on oil filter. This is a lot
simpler than an external oil filter.
The pump has a pressure relief valve built in, and 30mm
gears.The pump was fine, but I have issues with Bugpack quality. I
found metal slivers in the pump, although these may have come from a
bad "rebuilt" engine that I was sold. The gears had small machining
burrs which I carefully removed with a file. I think Bugpack should be
able to sell a pump that doesn't need cleaning up before installation.
The instructions were not as useful as I think they should be.
It's a nice pump. I'd recommend it, but you should shop around
to see if you can get better quality elsewhere. I just put one on my
Why does the pump need a built in pressure relief? With 26 mm
stock gears and some luck, you might get away with no extra pressure
However, with 30 mm gears there's a lot more flow. When the
temperature drops (as it does in Virginia winters) the oil is thicker
and outlet oil pressures at the pump can be very high.
What about those metal chips? I'm not sure they were in the pump but
always, always, clean new engine parts before installing them. This is
especially true of anything that has been machined, or has thread cut
into it. New parts shouldn't have metal flakes, but they often do, and
that's just reality. I recommend that you try to get higher quality
parts without this problem, but that might not always be practical, or
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| What about pump studs? This pump
shipped with bolts. This seems to be bad idea. Someone wrote that bolts
are used on aircraft VW applications. I have no idea if that's true,
but VW puts studs in at the factory. If Bugpack thinks cap-head bolts
are superior to studs, then the instructions with the pump should
explain that. The instructions were very terse.
In order to use the factory torque settings you have to use
studs. The bolt torque settings might be close, but the VW shop manual
torque values are for nuts on studs. Torque values for bolts will be
slightly different. Just go to your nearest specialty fastener store
and get longer studs. Just make sure they don't protrude inside the
case and hit the cam (again, someone wrote to tell me it is impossible
for them to protrude; maybe that is true, but check to make sure.) Also
make sure that they clear the engine tin and main pulley. You may have
to cut the studs. That's OK. My specialty fastener guy (who supplies
all the odd-ball hardware I need) says that metric threaded rod will
work just fine. While you are at the store, get a couple dozen wavy
The Oil Pump I installed on my old engine.
And add-on filter. On my old engine I installed the CB
Performance Maxi-pump 3 which has 26 mm gears. This is the same as
stock late model. (what's the difference between this and the Maxi-pump
4?). It allows for full flow filtering without tapping or modifying the
case. It has the late model stock 26 mm gears (not the heavy duty 30 mm
gears). Oil hose and filter adapter are Bugpack parts.
This job was a bear. I really needed the oil pump puller and
pulley puller. I loosened a couple of case nuts on either site of the
oil pump. I ended up tapping on a screwdriver on the edges of the pump
to drive the pump rearward. I did alternate sides. Not recommended. I
bent a stud with a stud removal tool: also not recommended. Just use
two nuts tightened against each other to remove studs. CB Performance
supplies some allen head screws. It turns out that these don't go into
the case nearly as far as the studs you just removed. So, I only
removed two studs, and replaced them with some longer studs.
I had to make spacers to go under the nuts, since the oil pump
cover plate was explicitly designed for allen head screws.
This is a really tight fit with the cooling tin
and pulley. It would have been better yet to get some slightly longer
allen screws, since the supplied screws were kind of short. Remember,
don't over torque these screws/studs. It's something like 5 foot
pounds. I used a little medium strength Locktite on the nuts.
I had to file the bolt holes in the pump and cover. They were
binding, and the pump is already a very snug fit. Don't forget to
re-torque the case nuts.
I don't know how to get this pump out of
the case. The oil pump puller uses the inlet and outlet holds in the
pump. This new pump doesn't have an outlet hole in the usual place. It
might be necessary to do the kind of gross thing I did and drive the
pump out with a hammer and screwdriver.
Remote Oil Filter
I mounted the oil filter on the right (driver) side inner
fender wall. It's was ok. The hoses held, but I was always worried
they'd pop off.
I may have to take off the filter to get out the #3 spark
plug. I bought some standard 1/2 inch id oil line hose. It's ok. The
cooling tin had to be cut, and grommets put on the oil hose to protect
it. At the bottom, the oil hose is about 1 3/8 inches (3.5 cm) from the
exhaust pipe. It's going to get hot, but I don't know yet if it will
melt. So far, I've driven the car a few miles and it's been ok. I might
have to put in a heat shield. Maybe this wouldn't be a problem with an
upswept baja type of exhaust (remember, I plan to turn this car into a
I use the oil filter adapter with the vertical attachments.
Every 90 degree bend increases back pressure. I put a Motorcraft HP1A
filter on so I get an additional 1 quart capacity without adding a
weird sump to the bottom of my engine.
In the photo below you can see the filter location inside the
rear driver side wheel well. I had removed the engine comparment
insulation. It was pretty far gone, and a mouse had put a store of
seeds back there.
Here is a closer shot. A little dark. Very dark. What we see
is a ratchet wrench on the #3 spark plug. I can reach it with the oil
filter in place, but it is tight. Clearly, it would make sense to
change the filter and plugs at the same time. I've considered other
locations, and will almost certainly move the filter when I do the Baja
Oil pressure is at least as good as with the somewhat worn
stock oil pump and no filter. Thank heavens. I have the pressure sender
mounted in the stock location, which is downstream from the filter. I
get around 60 psi cold, with 10W 40 oil, and around 8 or 9 psi hot,
with the idle at about 1000 rpm. Any idle speed much lower, and my
pressure drops below the dreaded 7 psi minimum.
Considering what CB Performance didn't tell me about
temperature senders (or what they don't know about temperature
senders), I'm wondering what they aren't telling about the oil pumps.
Special tools: oil pump puller, pulley puller, sheet metal
Parts: hose clamps, grommets, longer screws or longer studs,