Fuel pump pushrod length tolerance
Mike Rocket J. Squirrel Elliott
tolerance for the length of the fuel pump pushrod. They say it should
protrude 1/2 inch (12.7mm)or 13mm out of the intermediate flange.
My pushrod protrudes 11.94mm -- too short?
Who will be the first to respond with an off-color comment involving my
short pushrod and Inge?
--
Mike "Rocket J Squirrel" Elliott
71 VW Type 2 / 84 Westy: A poor but proud race.
KG6RCR
P.J.Berg
"Mike Rocket J. Squirrel Elliott"
<j.michael...@REMOVETHEOBVIOUSadelphiaDOT.net> wrote in message
news:pvGdnca2nq4...@adelphia.com...
Would that not differ with what style fuel pump you are to use(late/early)?
J.
Mike Rocket J. Squirrel Elliott
> "Mike Rocket J. Squirrel Elliott"
>
>>tolerance for the length of the fuel pump pushrod. They say it should
>>protrude 1/2 inch (12.7mm)or 13mm out of the intermediate flange.
>>
>>My pushrod protrudes 11.94mm -- too short?
> Would that not differ with what style fuel pump you are to use(late/early)?
It might very will make a diff. In this case I have what Bentley's call
the 68 - 70 type pump (disassembleable), and the pushrod measurement I
described is in the "single carburetor engine" type section. They don't
make any comment about pushrod length in the "double carburetor engine"
section.
John Connolly
it's too high, you must shorten the pushrod or stack gaskets between the
pump and spacer to drop pressure. If it's too low you need to remove gaskets
or use a longer pushrod.
but the spec is in the Bentley.
John
Aircooled.Net Inc.
"Mike Rocket J. Squirrel Elliott"
<j.michael...@REMOVETHEOBVIOUSadelphiaDOT.net> wrote in message
news:mK6dnSZi_Jp...@adelphia.com...
P.J.Berg
"Mike Rocket J. Squirrel Elliott"
news:mK6dnSZi_Jp...@adelphia.com...
> P.J.Berg wrote:
> > "Mike Rocket J. Squirrel Elliott"
> >
> >>For the stock mechanical fuel pump, Bentleys does not provide a
> >>tolerance for the length of the fuel pump pushrod. They say it should
> >>protrude 1/2 inch (12.7mm)or 13mm out of the intermediate flange.
> >>
> >>My pushrod protrudes 11.94mm -- too short?
>
> > Would that not differ with what style fuel pump you are to
use(late/early)?
>
> It might very will make a diff. In this case I have what Bentley's call
> the 68 - 70 type pump (disassembleable), and the pushrod measurement I
> described is in the "single carburetor engine" type section. They don't
> make any comment about pushrod length in the "double carburetor engine"
> section.
This is what my 1966 through 69 Type 1 Bentley says:
1.Place two new gaskets on the crankcase studs for pump and install the
intermediate flange on top of them.
2.Insert push rod in flange, tapered end down, to ride on eccentric cam of
distributor drive shaft.
3.Turn engine by hand until push rod rises to its highest point of travel.
4.Measure projection of rod above the flange; that is, from tip of rod to
upper flange surface.
measurement should be 0.51 inch (13mm)
5.Turn engine again to bring rod this time to lowest point of travel.
Measure from tip of rod to surface of flange. Measurement
should be 0.31 inch (8mm). Total pump stroke should be about 0.16 inch
(between 4 and 5 mm).
6.Set stroke to correct measurement by removing a flange gasket or by adding
one (or more).
And something to note:
Under instalation it tells you to fill lower chamber of pump with universial
grease.
J.
Mike Rocket J. Squirrel Elliott
>>P.J.Berg wrote:
> 4.Measure projection of rod above the flange; that is, from tip of rod to
> upper flange surface.
> measurement should be 0.51 inch (13mm)
+ or - what? That's my question.
Mike Rocket J. Squirrel Elliott
> specs aside, put a fuel pressure gauge on the output, you want 3-3.5psi. If
> it's too high, you must shorten the pushrod or stack gaskets between the
> pump and spacer to drop pressure. If it's too low you need to remove gaskets
> or use a longer pushrod.
Right -- the goal is a certain amount of fuel pressure, adjusting the
pushrod length is an indirect ballpark method I guess.
> but the spec is in the Bentley.
My Bentley says 3 to 5 psi for the "single carburetor" model, not 3 to
3.5 psi.
How much pressure does a 34 PICT want? And, for that matter, what does
"PICT" stand for?
Raymond Lowe
> For the stock mechanical fuel pump, Bentleys does not provide a
> tolerance for the length of the fuel pump pushrod. They say it should
> protrude 1/2 inch (12.7mm)or 13mm out of the intermediate flange.
>
> My pushrod protrudes 11.94mm -- too short?
>
> Who will be the first to respond with an off-color comment involving
> my short pushrod and Inge?
I don't have a Bentley, but I know that's wayyy too long for an alternater-
style pump. An alternator pump needs hardly any protrusion - I had to
grind mine down a lot and use 4 extra gaskets to fine tune the output to
2 3/4lbs. Pack the underneath well with grease. I used a little synthetic
grease on the pivot, then packed it full with good old Bosch distributor
grease. Everyone should keep a tube of this stuff handy. Lot's uses, such
as the pilot bearing inside the gland nut.
RT
--
E-mail=fullname-at-telus.net
Jim Adney
<j.michael...@REMOVETHEOBVIOUSadelphiaDOT.net> wrote:
>For the stock mechanical fuel pump, Bentleys does not provide a
>tolerance for the length of the fuel pump pushrod. They say it should
>protrude 1/2 inch (12.7mm)or 13mm out of the intermediate flange.
>
>My pushrod protrudes 11.94mm -- too short?
Generator and Alternator push rods are different lengths. Which do you
have and is this the one Bentley is talking about? You'll need the
late Beetle Bentley to get the alternator length.
Are you rotating the crank so you can measure it at its peak?
-
-----------------------------------------------
Jim Adney jad...@vwtype3.org
Madison, WI 53711 USA
-----------------------------------------------
Mike Rocket J. Squirrel Elliott
> On Sun, 22 Aug 2004 07:54:25 -0700 "Mike Rocket J. Squirrel Elliott"
> <j.michael...@REMOVETHEOBVIOUSadelphiaDOT.net> wrote:
>
>
>> For the stock mechanical fuel pump, Bentleys does not provide a
>> tolerance for the length of the fuel pump pushrod. They say it
>> should protrude 1/2 inch (12.7mm)or 13mm out of the intermediate
>> flange.
>>
>> My pushrod protrudes 11.94mm -- too short?
>
>
> Generator and Alternator push rods are different lengths. Which do
> you have and is this the one Bentley is talking about? You'll need
> the late Beetle Bentley to get the alternator length.
>
> Are you rotating the crank so you can measure it at its peak?
Hi Jim,
The engine is a new Mexican 1600 DP. I have an alternator mounted on its
gen stand, but I suspect that you are getting at something else. The
fuel pump is the one shown in the Bentley book as "old style"
(disassemble-able) for single-carburetor models -- the rod sticks
upward. They show another type with what seems to be a horizontal
pushrod, but that's not this engine. I did crank the crank for maximum
protrusion. Double-checked that.
Manual is new Bentley, Station wagon/bus 1968 - 1979
Jim Adney
<j.michael...@REMOVETHEOBVIOUSadelphiaDOT.net> wrote:
>The engine is a new Mexican 1600 DP. I have an alternator mounted on its
>gen stand, but I suspect that you are getting at something else. The
>fuel pump is the one shown in the Bentley book as "old style"
>(disassemble-able) for single-carburetor models -- the rod sticks
>upward. They show another type with what seems to be a horizontal
>pushrod, but that's not this engine. I did crank the crank for maximum
>protrusion. Double-checked that.
I'm not that well versed in the beetle engines, but I know that they
had to do something different with the fuel pump when they introduced
the engine with an alternator. I'm pretty sure this included a shorter
pushrod. None of this will be mentioned in your bus Bentley because
the type 1 engine with alternator wasn't introduced until 74 (?) by
which time the bus already had the type 4 engine.
Your manual only covers type 1 engines up to 71 and type 4 engines
thereafter.
Since your engine is a type 1 alternator engine I think you need to
find a manual that covers it and see what it says about the pushrod.
The actual pump style may vary over the years, but IIRC, the
alternator pump is angled strangely to help it clear.
Investing in the late Beetle Bentley will be useful for other reasons,
too. Your new engine will have the 8mm head studs, and, while you
should not have to worry about them for a long time, you should know
that you'll pull them out if you use the 10mm torque setting on them.
You'll need the late Beetle Bentley to get the right torque value.
Peter
larger size of the alternator behind the pulley. This meant that the pump
operating lever was repositioned to almost flush with the base of the pump.
Because of this, a shorter 100mm pushrod was fitted (previous length was
108mm) which should therefore project 5mm. The 'old style' straight pump
should not fit with the alternator and you will require the later pump and
pushrod. As for the pushrod projection at full stroke, are you using a
genuine intermediate flange? It may be of no consequence but is something
to be considered.
Max fuel pressure should be 3.5psi at 3,400rpm. VW states that it does not
matter if the pressure is slightly higher than this.
"Jim Adney" <jad...@vwtype3.org> wrote in message
news:rdvni0puoj81hau1i...@4ax.com...
Mike Rocket J. Squirrel Elliott
> On Mon, 23 Aug 2004 18:39:51 -0700 "Mike Rocket J. Squirrel Elliott"
> <j.michael...@REMOVETHEOBVIOUSadelphiaDOT.net> wrote:
>
>
>> The engine is a new Mexican 1600 DP. I have an alternator mounted
>> on its gen stand, but I suspect that you are getting at something
>> else. The fuel pump is the one shown in the Bentley book as "old
>> style" (disassemble-able) for single-carburetor models -- the rod
>> sticks upward. They show another type with what seems to be a
>> horizontal pushrod, but that's not this engine. I did crank the
>> crank for maximum protrusion. Double-checked that.
>
>
> I'm not that well versed in the beetle engines, but I know that they
> had to do something different with the fuel pump when they introduced
> the engine with an alternator. I'm pretty sure this included a
> shorter pushrod. None of this will be mentioned in your bus Bentley
> because the type 1 engine with alternator wasn't introduced until 74
> (?) by which time the bus already had the type 4 engine.
>
> Your manual only covers type 1 engines up to 71 and type 4 engines
> thereafter.
>
> Since your engine is a type 1 alternator engine I think you need to
> find a manual that covers it and see what it says about the pushrod.
> The actual pump style may vary over the years, but IIRC, the
> alternator pump is angled strangely to help it clear.
I'm not seeing any strangeness here. The pump looks exactly like Section
3, Page 9 of the Bentleys Stationwagon/Bus 1968 - 1979 manual. Or maybe
because I am not seeing anything strange is, in fact, strange? The gen
stand looks just like the one shown on Page 54 of Section 5. Given this,
I am /ass/uming that their stated pushrod max extension of .5'' (13mm)
is correct, and mine is worn down. But, as John pointed out, hang a fuel
pressure gauge on the line and see what it is doing.
>
> Investing in the late Beetle Bentley will be useful for other
> reasons, too. Your new engine will have the 8mm head studs, and,
> while you should not have to worry about them for a long time, you
> should know that you'll pull them out if you use the 10mm torque
> setting on them. You'll need the late Beetle Bentley to get the right
> torque value.
This is true -- this new engine does have 8mm stays. Can someone advise
the correct torque value for them?
Peter
distributor drive gear? This would directly affect the height the pushrod
sits at. You are supposed to have 44.6mm of space from the top of the
distributor drive to the top of the drive bore. However, the way VW lays
out the procedure, you should know the full depth of the bore and the length
of the drive (from top to where it sits on the shims) and then calculate for
the shims. It seems to me, whether fitting an alternator or dynamo, either
pushrod length should come out right.
"Mike Rocket J. Squirrel Elliott"
<j.michael...@REMOVETHEOBVIOUSadelphiaDOT.net> wrote in message
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