rockatansky

Don't worry, It was my fault, didnt know which picture you were refering at. Erik I would like to ask you something that comes to my mind each time I see your messages...

Why is your car in your avatar resting on a side!!!

Dave928S

Joaquin
You should also replace the fuel filter that you have in the car now (it'll be full of crap) ... just so you get rid of any chance of dirt coming back from that filter to the outlet of the pump. That's unlikely because you'll have a check valve to stop that happening ... but better to be safe. The one that you put in temporarily on the inlet side, will protect the new filter during the testing and run stage.

You can cut the old filter open to see what's inside, which should give you an idea of what you're trying to clean out of the tank and lines .... and whether it's rust or rubber particles, and not just dirt, which would give you an indication you have degraded lines internally.

What was likely to be happening before, with the backflow of fuel from not having a check valve, was dirt from the filter was being pushed back into the pump. The pump ran OK for all that time before because it was running continuously with no chance of backflow .... as soon as you turned it off and on a few times you got backflow and perhaps dirt back into the pump.

rockatansky

Hi Dave,

Ok, yes I will do my best to catch dirt with both filters. Of course once the system seems clean to me I will put a new Mahle filter. I have the Dwayne tutorial for removing the tank and also the sharkskin tutorial attack on fuel lines.

I sent back the ruined pump to France and in the meantime I have ordered to Germany a 49 euros pump with the same number for the 928 with the same characteristics, 5bar 1,6L of flow, connectors, etc, but obviously made in china or whatever. I will use it just for this tasks and will let the replaced Bosch for installing when I assume that the system is clean and ready for a drive.

Yes, I will like to see that. I will post high res pictures here for everybody to see what can clog two pumps in a row.

Yes, that explains why the pump worked great for 35 minutes (everthing flowing one direction) and then get jammed as soon as we started cranking. And sh*t coming back.

One thing I would like to do before next try also is to remove the CE Panel, review all relays, fuses and clean connections. I think is a good time to do this job and leave the panel like new. I will see where I can get stabilant 22, seems good for that task... thanks!.

Dave928S

That's a good idea ... cheap pump and old filters for all testing and initial run ... then once all is OK and running, pull those off and install new pump and filter

rockatansky

...we are finally 'there'.



http://www.youtube.com/watch?v=zONaP_5hVBA

Will be great to hear your opinions about what you see (and what you hear).

Some facts to add to what's written on the video:

First you should know that in the configuration there is a second fuel filter attached before the fuel pump (to avoid dirt problems at this stage, ...read previous posts). It has worked great!, but have that in mind... because this could be related with any engine behavior in the video.

Idle seems quite low rev.

I think exhaust could smell a bit to fuel.

Throttle reacts with some delay. You press the pedal and it revolutionizes a bit later.

Temperature climbs to the first white thin line after some minutes and keeps there without climbing anymore for the rest of the session.

Battery gets charged during session.

Running time, about an hour. From the start at the begining of the video to the stop at the end. No stops between.

Next steps we have in mind:

-Any advice you gave me. And...

-more starts.

-remove extra filter and connect pump to car's stock wires (now is direct to battery). Check with that config.

-remove cheap pump and the current fuel filter and set the new bosch and a brand new mahle filter.

-A friend is lending me in the next weeks a Waekon Universal Electronic Fuel Injector Quick Probe. This one: http://www.amazon.com/gp/product/B0002SR5LW maybe I could use it to check the injectors and get some more information.

-We have tested some days ago for spark, but only in one plug. So maybe its a good time to check it on every spark plug.

Any comment on anything sure will help. Thanks a lot to everyone that has helped here at rennlist (specially Dave). Of course now begins the second phase, I will keep posting the progress and asking, I will not stop until it moves (and fast).

Dave928S

You're on the home stretch ... it won't be long until you're driving. Check all of your suspension and brake components before you drive ... safety first

Mrmerlin

the tapping should go away after it gets warmed up , it does sound good

Dave928S

Joaquin

Some other things to check.

Make sure that your air cleaner element is clean by carefully blowing with compressed air, or put a new one in.

While you have the air filter out, check that the large flap, at the bottom of the round opening in the base of the air filter housing, will move very easily without catching or sticking. This is the plate/valve I referred to before, which senses air flow volume and controls the fuel pressure, and therefore the flow, to the injectors. If it sticks at all it can give you lag in throttle response, rough/low/high idle, and other irregular throttle response anywhere in the rev range. The whole system is more complicated than that, and there are lots more things to check, such as fuel pressures ... but you need to have a good understanding of the whole system before you start making those adjustments.

While you have the motor running check all your vacuum hoses for leaks. A vacuum leak could also give you irregular idle.

It sounds good, and probably there's not too much wrong with it that a good Italian tune up won't fix (in your case Spanish).

Landseer

Congratulations.
Audio isn't great on the video, but that engine sounds very good to me.

I like the way you did this carefully from the beginning.

The engine itself is sitting pretty low in the bay, so I suspect MM's are in your future, as they are for all of us saving one.
The only reason I mention it now is for noise consideration.
Check to see if the fan blades are grazing the lower radiator shroud.

Dave928S

So do I
It makes spending time posting worthwhile.

rockatansky

Thanks a lot MrMerlin, Landseer and Dave for your comments about the sound of the first start. And thanks for your comment on doing it everything carefully, that really encourage me to keep working to make this baby live again...

As we say, two steps forward and one back. This time it was two forward and two (or three) back. Sorry but this time I don't have a video. I forgot to carry the camera to the place where I have the car and have to decide to let another week pass or try a start without the camera. Well, now I know I should have waited because now I can't give you a very precise information of the yesterday session. I will try to describe.

Well, we started the car. It starts at 1st try. The sound was not very good at the begining (more or less like in the video the other day). Car was at idle and adapting well through time (as a living being). If you remember, the other day, the idle was very low (rpm needle almost dead). But today and after 30 minutes the car starts sounding really good, probably with it's 'stock' sound or near. It keeps idle at around 900 rpm on its own nicelly.

Well, after a while of good sound we decide to push the throttle a bit. We did slow pushings of the pedal from 1000 rpm to 2200 max. We did that 4 or 5 times spaced 5 seconds between them. Good sound.

Suddenly the car stops on one of the pushings.
- we turn key off
- A small cloud of smoke climbs up through the engine bay
- Smell was like 'electric' burn. (Not oil or fuel).
- CAr is still on jackstands, so a fast look under the car a few seconds after the stop, and we saw smoke coming out directly from the starter and rapidly dissipating.

Some hours later with the car cold, we turn the key to confirm the dead starter. No sound.

One thing I would like to mention (and which the incident makes it more relevant):

The battery needle was climbing from around 12V to around 13V each time we push the throttle. It behaves almost like the rpm needle, climbs up when pressing the pedal. Don't know if that is normal. Other cars I have seen only has a battery light without needle, so don't know if it's normal in our 928 that the needle climbs up on voltage when accelerating (how does it behave on yours?). ...If it is not normal, could it be that some electrical problem is making the voltage climb on accelerating and that is frying things up?.

I have no idea, of course, and don't know if it has sense... but could it be that the starter could have done it's job starting the car but it has kept engaged in someway without noticiable problems during the first 30 min of idle. When we have started rev the car it could have got fried. Just some ideas.

Well, don't know how to attack this problem. First thing I have done is check price of a starter. They are expensive, but I see that 928intl has them used for 100$. If they work maybe a used starter is the way to go.

In any case (as you surely advice me), the first thing is to know what has caused the problem and fix it, before installing any new one.

Sorry about the long post. Next time I will not forget the camera. Anyhing that you think that I could check, let me know. As always thanks.

Mrmerlin

first disconnect the battery,
it sounds like the starter wires are shorting out on the cross member check for this after the disconnect

Dave928S

It's been a while since I checked this thread and just saw these last two posts. Don't assume that the starter is fried ... the fact that you lost power to ignition indicates a wire short as Stan said. If it was just a starter failure then you wouldn't have lost power to the ignition circuit.

rockatansky

After so much time I guess you thought I have already call 'The Wolf' and ask him to get the car to the Monster's Joe wreck yard and turn it into a box of iron. But hey!, look...


Another round of double bourbons for rennlist people!!!.

Ok. the last time I wrote was when after some days starting the car still on jacks, the starter seems to got fried.

Now I can confirm you that it got fried. After removing it from the car, I open it and found that it was completely burnt and every little piece of metal was triturated inside it. My guess, that for some reason, the starter kept engaged during the whole hour while the car was idle. Stand heroically, but couldn't handle higher rpms when we push the throttle at the end of the session (around 2200 when smoke come out from the starter surroundings and car stopped).

Some days later we found the reason. The key lock cylinder. When you turn the key and activate the starter, after you get your hand away, it should come back alone and stop the starter, leaving the engine already running. Well, this cylinder must be broken and doesn't come back enough, so the starter seems to keep receiving volts and keeps engaged after you get your hand away.

We confirm that without the starter mounted, using the multimeter, while we wait for a refurbished one to come from Pelican. We haven't changed the key cylinder yet. But we are aware of the problem now and we have our own trick. It works well if you manually turn left the key 45 degrees after cranking doing what the spring inside the lock should have done. Here is the new refurbished starter, it's cheap, good looking and working great!.



I know I should change the lock cylinder asap. But one of the most important philosophies I have learn on car repair this months is, '...do not touch anything that you could avoid touching, and just keep going forward...'. This way we are minimizing the risk of taking steps back. Now that the car is running we can go back to everything we left on the way, prioritizing what's more important. There are many things yet but the idea in mind is ending with everything in good shape and working.

While we wait, I removed the CE Panel from the car. Clean every contact and spread Stabilant 22A on every connection following the SharkSkin's 928 panel page (a lot of some kind of glue where spread all around it, also many oxid in some contacts, etc). Reinstall the panel and some of the electrical gremlins got magically solved, like for example the electric passenger mirror not moving when using the joystick, now it works.



The problem, we will focus on now is the low rev at idle. The car has always run with low idle in all those first starts, at about 500 rpms or around unless we press the throttle (by the way, I'm wondering how many rpms are you having in your 928 when idle?). Also we feel a slow response when pushing the throttle, you have to wait until the engine turns faster after you push it. So I think that in that condition is easy that the car stops here and there when it is idle or reducing gears, etc, whenever the throttle is not pushed. Dave already gave me an advice about that, but we didn't do anything because the problem with the starter shows up and we forgot about revs. He told me to check a flap at the bottom of the air filter housing, could it be?.

Probably that is a good starting point. An image or comment about what to check down there sure will help. Which part is in there?, idle valve maybe?. As soon as I know it I will search for information about it and how to check it or look for dirt, stuck moving parts, etc.

In a fast review of rennlist posts about low idles, one call my attention, from Erik. He has a similar problem, also with a CIS, his from '81, mine is '80, but finally he finds out the problem it's on the Warm-up regulator. His car goes better when it gets hot. I think mine goes worst after some driving. So I think is not the same problem but in that thread sure I will get plenty of good information, I will read it carefully. He narrows the problem applying a hairdryer on the wur and then starting... that's the kind of trick you could not find at the WSM for sure.

In this first readings, I see there are many things that could be related. An aux air valve, an idle air valve (maybe those are the same?), the wur, the air filter (the orange air filter was one of the first things I bought at Pelican if that helps), a mixture screw?, fuel pump, pressure gauges to check injection, timing belt, among other things.

I read also that some of this components used to get a lot of crap in them, not letting them work well and closing the pass of air, making the car idle wrong. (It will not surprise me that this could be related with the problem).

By the way, remember the double filter we install, with the cheap pump, etc. They do their work perfectly, many hours filtering the tank. Now it has the proper Bosch pump with the check valve, only one clean filter of course in place, a new fuel hose from the tank to the pump bought at Porsche, etc. And everything seems too work now really well back there so I think pump is not related with the low revs.



It will be great to hear any advice about where to start looking in search for the reason of the low revolutions at idle behavior before getting any deeper, buying a pressure gauge, etc.

(Sorry for the long post, too many weeks without posting and wanted to thank and share the progress with the forum...).

Mrmerlin

looking good glad things are getting sorted out.

In the last picture you posted of the new pump and filter,
you need to spin the clamps so they are not on the undersides of the pump and filter otherwise
Note spin the clamps so the screws are away from the outer edges of the pump and filter,

the pump cover will rub on them this can damage the filter or pump