Fuel pump pushrod length tolerance

Would that not differ with what style fuel pump you are to use(late/early)?

J.

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.

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.

but the spec is in the Bentley.

John Aircooled.Net > > "Mike Rocket J. Squirrel Elliott"

use(late/early)?

use(late/early)?

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.

• or - what? That's my question.

Right -- the goal is a certain amount of fuel pressure, adjusting the pushrod length is an indirect ballpark method I guess.

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?

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

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?

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----------------------------------------------- Jim Adney snipped-for-privacy@vwtype3.org Madison, WI 53711 USA

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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

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.

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----------------------------------------------- Jim Adney snipped-for-privacy@vwtype3.org Madison, WI 53711 USA

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Pumps for engines fitted with alternators were 'angled' so as to clear the 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.

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.

This is true -- this new engine does have 8mm stays. Can someone advise the correct torque value for them?