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> Non starting 1.7 - 1971, Djet .....
Bibble
post May 13 2020, 10:45 PM
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Hello all, looking for some help with a 1.7 from 1971, running Djet. Apologies for the length of the post but thought it helpful to give some background and an overview.

The car has been off the road for a couple of years having attention to tin worm in the corners and jacking points. It ran ok if very rich prior to coming off the road so tended to cut out once it was warm as you decelerated but it restarted easily enough

As I started to pull the car together I thought it wise to get things as clean as I could to try and overcome the rich running as above. I have the correct ecu fitted which has been tested and checked as good. I had the injectors tested and cleaned (correct yellow ones) The MPS is a NOS one good vacuum.

When I first tried to restart the car there were some fuel leaks from the pipes around the engine bay, and it seemed like from the pump itself, but crucially for this tale the pump was pushing fuel around the loop in the engine, past all of the injector take off points and back to the tank. I had a spare pump so swapped it with the one in the car. (But have subsequently swapped back) as the spare one once fitted did not pump fuel around the loop, but buzzed away quite happily.

The fuel pump/s pump fine when attached direct to a battery, pressure still a little high at mid 30s.  When attached to the cars wiring both do their 1.5 seconds initial buzz and then stop. When measured, the voltage from the fuel pump plug connector is around 11.80v. When cranking the voltage drops to and fluctuates around 10v. But putting the fuel pump connection back to the pump and cranking it there is no fuel pushing around the loop in the engine, no pressure when tested as against the 30s when direct wired.  Fuel pressure tested at the take off point on the injector rail.

I thought I Ishtar also have a problem with the FI points in the distributor but using a Noid light, I’m getting pulses at all 4 of the white injection connection points. I haven’t taken a jet out to check that fuel is actually coming out as yet. I have checked and am getting a spark at all 4 plugs. 

There is no sense of firing even when direct wiring the fuel pump so fuel is flowing around the loop, the pulses should be kicking fuel out and the spark should be there but no firing. I presume therefore that the fuel pump actually wired to the vehicles system and pumping fuel (and not direct wired to a battery via clamps) is part of the Djet functioning and then getting a fire, otherwise as it it has fuel, it has spark, it has a Fi pulse, nothing has been changed in terms of points position, valve timing etc since it last ran so why wouldn’t it? even a horribly rough cough and splutter would do! 

I have checked the fuses on the relay board swapped out the relays with the headlight ones - seem good with the lights operating fine, cleaned up all of the connections on the relay board, cleaned the FI earths on the engine block but cannot get the fuel flowing. What am I missing! (IMG:style_emoticons/default/confused24.gif)

Would appreciate any thoughts.

Best wishes

Jonathan
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dlee6204
post May 14 2020, 05:50 AM
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You need to check to see if your fuel injectors are actually spraying. Unbolt all four and see if they spray while cranking.

Are you sure you have your supply/return lines hooked up correctly?

You said you have spark but how have you verified that you have spark?

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BeatNavy
post May 14 2020, 06:12 AM
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QUOTE(dlee6204 @ May 14 2020, 07:50 AM) *

You need to check to see if your fuel injectors are actually spraying. Unbolt all four and see if they spray while cranking.

Are you sure you have your supply/return lines hooked up correctly?

You said you have spark but how have you verified that you have spark?

(IMG:style_emoticons/default/agree.gif) Make sure your lines are plumbed correctly. If you have fuel pressure, and the noid light shows injectors attempting to fire, then I would think you'd see fuel, unless you have a blockage somewhere (but then you wouldn't have pressure at the rail, right?).

Here's a pic of the stock pump:

(IMG:http://www.914world.com/bbs2/uploads/post-8684-1473898222.jpg)

It sounds like that might be leaky, too? I'd dump the 3-port pump buy and fit one of those Bosch 2 port pumps. New pump that doesn't leak and it simplifies fuel hose routing.

And yes there may be more than one thing going on that's keeping you from getting spark.

If you search on this site there is a fuel pump troubleshooting guide. If you can't find it, PM me. I have a PDF version of that I can send you.

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dr914@autoatlanta.com
post May 14 2020, 08:26 AM
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sounds like everything is working properly. I would make sure that the lines are properly routed, remove the right rear injector rail like and turn the key on and off a few times and make sure that fuel "spits" out of the line going to this rail. If not the lines are backwards and that is why you have no pressure.
Also look at the plugs and make sure that they are not fouled. That is a start

QUOTE(Bibble @ May 13 2020, 09:45 PM) *

Hello all, looking for some help with a 1.7 from 1971, running Djet. Apologies for the length of the post but thought it helpful to give some background and an overview.

The car has been off the road for a couple of years having attention to tin worm in the corners and jacking points. It ran ok if very rich prior to coming off the road so tended to cut out once it was warm as you decelerated but it restarted easily enough

As I started to pull the car together I thought it wise to get things as clean as I could to try and overcome the rich running as above. I have the correct ecu fitted which has been tested and checked as good. I had the injectors tested and cleaned (correct yellow ones) The MPS is a NOS one good vacuum.

When I first tried to restart the car there were some fuel leaks from the pipes around the engine bay, and it seemed like from the pump itself, but crucially for this tale the pump was pushing fuel around the loop in the engine, past all of the injector take off points and back to the tank. I had a spare pump so swapped it with the one in the car. (But have subsequently swapped back) as the spare one once fitted did not pump fuel around the loop, but buzzed away quite happily.

The fuel pump/s pump fine when attached direct to a battery, pressure still a little high at mid 30s.  When attached to the cars wiring both do their 1.5 seconds initial buzz and then stop. When measured, the voltage from the fuel pump plug connector is around 11.80v. When cranking the voltage drops to and fluctuates around 10v. But putting the fuel pump connection back to the pump and cranking it there is no fuel pushing around the loop in the engine, no pressure when tested as against the 30s when direct wired.  Fuel pressure tested at the take off point on the injector rail.

I thought I Ishtar also have a problem with the FI points in the distributor but using a Noid light, I’m getting pulses at all 4 of the white injection connection points. I haven’t taken a jet out to check that fuel is actually coming out as yet. I have checked and am getting a spark at all 4 plugs. 

There is no sense of firing even when direct wiring the fuel pump so fuel is flowing around the loop, the pulses should be kicking fuel out and the spark should be there but no firing. I presume therefore that the fuel pump actually wired to the vehicles system and pumping fuel (and not direct wired to a battery via clamps) is part of the Djet functioning and then getting a fire, otherwise as it it has fuel, it has spark, it has a Fi pulse, nothing has been changed in terms of points position, valve timing etc since it last ran so why wouldn’t it? even a horribly rough cough and splutter would do! 

I have checked the fuses on the relay board swapped out the relays with the headlight ones - seem good with the lights operating fine, cleaned up all of the connections on the relay board, cleaned the FI earths on the engine block but cannot get the fuel flowing. What am I missing! (IMG:style_emoticons/default/confused24.gif)

Would appreciate any thoughts.

Best wishes

Jonathan

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Bibble
post May 15 2020, 10:53 PM
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Thank you all for the suggestions and the offer Rob of the pdf. Things have moved on a bit now, after more cleaning of connections checking things were connected correctly. Fuel pump now working when attached to the loom, and pushing fuel around the loop. The connections were the right way round. The spark testing the old fashioned plug pulled, cleaned and set on the block and cranked all 4 good plugs were a little sooted up.
Checked for fuel delivery through the injectors ..... nothing from any of them - (noid light confirming pulses at each on the wiring connectors to the injectors) despite being professionally tested and cleaned. Tried a couple of old uncleaned injectors and they delivered fuel .....l so will swap the cleaned ones out for the old set today and see what happens. Can you damage injectors ? Can’t see how in theory a newly cleaned set have all failed - only cleaned at the end of last year and unused prior to installing .....
best wishes
Jonathan
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dlee6204
post May 16 2020, 03:32 AM
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From my experience with cleaned/rebuilt injectors... if they sit at all they will stick. Lightly pushing on the pintle to free them up is usually all it takes. Your experience may vary.
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Bibble
post May 16 2020, 09:44 PM
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Thanks for the advice Doug, hadn’t heard of that before. How hard a light push are we talking? I haven’t got any injection cleaning fluid would that be an idea to give them a bit of a soak first?
The good news is after swapping the cleaned ones out for an old set in my garage, the car fired into life after 3 years !!! Brilliant.
But I still have a fuel leak on one pump that is able to push the fuel around, the other initialises and buzzes but cannot push the fuel around. Does any know of an overhaul kit for the three port pump? Or should I go for the two port kit that AA sell and just replace it in the original spot on the car.
I don’t want to move it’s position particularly, and understand the kit allows that to happen, and just connects the return line direct back to the tank. Appreciate any thoughts, and thanks for the help thus far.
Best wishes
Jonathan
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BeatNavy
post May 17 2020, 05:16 AM
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Congrats on getting the car running! The 2 port swap is usually done with the Bosch 69133, or something equivalent. Here's a thread that discusses how the swap is done:

http://www.914world.com/bbs2/index.php?showtopic=217906
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Bibble
post May 17 2020, 05:50 AM
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Thanks for the link Rob, presumably the spec of the pump needs to be around the 28- 30 range pressure range?

On swapping the Bosch 3 port pumps out, the original leaking but delivering pump serial number ends in 0011, the non leaking pump 3005. Are they both appropriate for a Djet system for a 1971 car? The 3005 seems to work ok but hasn’t got the oomph to push the fuel round ? Or is it just an internal failure that means it’s dropping its output?

Thanks again

Jonathan
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BeatNavy
post May 17 2020, 07:34 AM
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QUOTE(Bibble @ May 17 2020, 07:50 AM) *

Thanks for the link Rob, presumably the spec of the pump needs to be around the 28- 30 range pressure range?

On swapping the Bosch 3 port pumps out, the original leaking but delivering pump serial number ends in 0011, the non leaking pump 3005. Are they both appropriate for a Djet system for a 1971 car? The 3005 seems to work ok but hasn’t got the oomph to push the fuel round ? Or is it just an internal failure that means it’s dropping its output?

Don't know what's wrong with your existing fuel pumps. Don't see a reference to p/n 0011, but 005 is definitely a Bosch fuel pump for our cars. More info here: https://members.rennlist.com/pbanders/DJetParts.htm

If you go with an aftermarket FI fuel pump they are all going to be rated to at least 3 bar (~45 psi). You definitely need to check / adjust your pressure to D-Jet's happy place of ~28-30. Likely it will still be there but worth checking.
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