Fuel pump push rod length?

Andy Andy\'s Adventures

2,820 posts · joined Nov 2002 · 26 Apr 2011, 2:57 pm

#837754

1600TP
Does anyone know the correct length, and wear limit?
Getting ready to assemble a motor, the used one is 107.7mm. The motor was running fine before pulling from the car.
I have an unused one that is 108.6mm long, but the quality does not look the best, so am thinking of using the old one. I would polish the ends of the new one before using it, so that will shorten it a little.

Also any links to web pages showing things to check for before re-assembly, and reassembly procedure would be great. I've been through everything I can think of, motor is down to long block stage and all seems in order
I have a few manuals, and have checked most things so far, main reason for stripping down was a good clean up, new seals all round and stripped plug threads
Bearings and clearances seem in spec so far, so will leave that as is,
I've re-built all the ancillaries though, carbs, generator, starter motor

Thanks for your help!

68AutoBug Beetle Restorer - Experience over 138\% - YIKES --

11,654 posts · joined Aug 2002 · 26 Apr 2011, 3:52 pm

#837764

Andy wrote:1600TP
Does anyone know the correct length, and wear limit?
Getting ready to assemble a motor, the used one is 107.7mm. The motor was running fine before pulling from the car.
I have an unused one that is 108.6mm long, but the quality does not look the best, so am thinking of using the old one. I would polish the ends of the new one before using it, so that will shorten it a little.

Also any links to web pages showing things to check for before re-assembly, and reassembly procedure would be great. I've been through everything I can think of, motor is down to long block stage and all seems in order
I have a few manuals, and have checked most things so far, main reason for stripping down was a good clean up, new seals all round and stripped plug threads
Bearings and clearances seem in spec so far, so will leave that as is,
I've re-built all the ancillaries though, carbs, generator, starter motor

Thanks for your help!

Hi Andy,

From what I've read it all depends on the bakelite base You have...
and I don't really believe they were all the same length...
and the because of the different lengths the pressure can vary from 1.5 to about 8 PSI... 2-3 PSI being all You need..
so, some bases need to be shimmed to obtain the correct pressure.. and some shafts need to be shortened for the same reason...
try the shorter one and see how You go...
if its not long enough You can grind or file a bit off the base..
but they are usually OK.. over pressure seems to be more common which can lead to needle and seat leaking...

cheers

LEE

- Helping keep Air Cooled VWs on the road - location: SCONE in the Upper Hunter Valley - Northern NSW 320 kms NNW of SYDNEY---

Joel Now containing 100\% E-Wang

9,368 posts · joined Feb 2006 · 26 Apr 2011, 4:23 pm

#837773

Originally they were 108mm for Generator engines and 100mm for Alternator engines.

But we all know what aftermarket replacement parts can vary like.

Andy Andy\'s Adventures

2,820 posts · joined Nov 2002 · 28 Apr 2011, 2:18 am

#838170

Thanks guys, I'll Stick with the original then!

Lee as I understand the operation, changing the block height will vary the volume it can output, the spring sets the pressure?
The book I have also quotes 3-4mm height change, I guess that let's you see if there is wear on the crank?

Interestingly the type 4 has no block to vary the height, the push rod I replaced recently was 5.5mm shorter than a new one !