Excessive Cranking on start-up, Assistance request Options

[Van B]

Hello scholars and masochists.

I’m requesting help on solving the issue of excessive cranking on start-up. Not once since I bought the car has it ever fired right up like others described for their cars. I had hoped that this issue was related to the other issues I’ve solved with the help of my friends here, but no luck. The behavior remains unchanged.

To start this off, I rigged a little hidden fuel pressure gauge to the car so that you all can see for yourself. For the context of this attempt, the engine is cold at around 60F, I did not touch the throttle and the ignition was in the on position prior to cranking.

https://youtu.be/DTTQ1zQJkJo


https://www.youtube.com/watch?v=DTTQ1zQJkJo


Edit: moving on to a new phase at post #152

http://www.914world.com/bbs2/index.php?s=&...t&p=2995793


Please advise and thanks in advance.

Van

[brant]

I didn't read the whole thread.
but I experienced the exact same symptoms with a 3 port Djet pump

I opened up the working pump
its a smart design
there is a rubber seal inside that also causes the pump to close when turned off and hold fuel pressure in the fuel lines...

I replaced the seal.
now when I crank the starter it fires right off

where as before it had to crank 5 times to build up the correct fuel pressure before starting....

these are old pumps
I did not realize they were also functioning as a pressure accumulator
not surprised a 50 year old piece of rubber was not doing its job

opening these pumps is a pain in the butt....
having a factory type crimping tool would help, but I don't have one...
so my home rebuild is not a pretty site.


I bet if you change the pump... your problem will go away


before I fixed mine... I would key on the ignition 4-5 times to build pressure...
then hit the starter and it would fire off immediately

brant

[wonkipop]

I didn't read the whole thread.
but I experienced the exact same symptoms with a 3 port Djet pump

I opened up the working pump
its a smart design
there is a rubber seal inside that also causes the pump to close when turned off and hold fuel pressure in the fuel lines...

I replaced the seal.
now when I crank the starter it fires right off

where as before it had to crank 5 times to build up the correct fuel pressure before starting....

these are old pumps
I did not realize they were also functioning as a pressure accumulator
not surprised a 50 year old piece of rubber was not doing its job

opening these pumps is a pain in the butt....
having a factory type crimping tool would help, but I don't have one...
so my home rebuild is not a pretty site.


I bet if you change the pump... your problem will go away


before I fixed mine... I would key on the ignition 4-5 times to build pressure...
then hit the starter and it would fire off immediately

brant

@brant

can you remember where you got that little seal from?

[brant]

I didn't read the whole thread.
but I experienced the exact same symptoms with a 3 port Djet pump

I opened up the working pump
its a smart design
there is a rubber seal inside that also causes the pump to close when turned off and hold fuel pressure in the fuel lines...

I replaced the seal.
now when I crank the starter it fires right off

where as before it had to crank 5 times to build up the correct fuel pressure before starting....

these are old pumps
I did not realize they were also functioning as a pressure accumulator
not surprised a 50 year old piece of rubber was not doing its job

opening these pumps is a pain in the butt....
having a factory type crimping tool would help, but I don't have one...
so my home rebuild is not a pretty site.


I bet if you change the pump... your problem will go away


before I fixed mine... I would key on the ignition 4-5 times to build pressure...
then hit the starter and it would fire off immediately

brant

@brant

can you remember where you got that little seal from?

I don't recall
but I think.....

mcmark had built a few and had found the correct o rings... misc
I think he sent me a couple in an envelope at the time.
but it was a few years ago

brant

[wonkipop]

I didn't read the whole thread.
but I experienced the exact same symptoms with a 3 port Djet pump

I opened up the working pump
its a smart design
there is a rubber seal inside that also causes the pump to close when turned off and hold fuel pressure in the fuel lines...

I replaced the seal.
now when I crank the starter it fires right off

where as before it had to crank 5 times to build up the correct fuel pressure before starting....

these are old pumps
I did not realize they were also functioning as a pressure accumulator
not surprised a 50 year old piece of rubber was not doing its job

opening these pumps is a pain in the butt....
having a factory type crimping tool would help, but I don't have one...
so my home rebuild is not a pretty site.


I bet if you change the pump... your problem will go away


before I fixed mine... I would key on the ignition 4-5 times to build pressure...
then hit the starter and it would fire off immediately

brant

@brant

can you remember where you got that little seal from?

I don't recall
but I think.....

mcmark had built a few and had found the correct o rings... misc
I think he sent me a couple in an envelope at the time.
but it was a few years ago

brant

yes, if i remember right its the world's tiniest o ring that sits in a channel groove in that little needle valve. or its some kind of tit thing. would need to look at my old photos to remind myself.
be handy to know where to get hold of one --- just in case.

fortunately that was the only one in both fuel pumps that wasn't shot.
the main culprit in the pumps i rebuilt was the electrical plug o ring seal.
which required a complete drill down and full disassembly to renew.

the trick to the paper thin alum cap on the end of the spring housing of the top port assembly is to use a socket over the cap and hold it all in a vice. the socket distributes load to the stepped section of the cap and stops it distorting. which it will do at the drop of a hat. if it distorts it will screw up the operation of the relief valve. then work at it very gingerly with a screw driver. reverse for reinstall.

i totally destroyed the first one i did. and you can't buy them anywhere.
i bought two screwed pumps from a VW guy in the states for $20.00 each and had then freighted slow mail. just to get some spare caps. and perfected the technique.