Engine Red-lines on Start-up
 

Today was a momentous day… sorta…

After spending 8 months on a total refresh of my 1979 SC Targa, today was the day to ‘start her up!’ I put 5 gallons of fresh fuel in the tank, checked the oil (again) and turned the key – it took some cranking to get fuel to fill the new lines, accumulator, filter etc. and when it finally did –

Va – Rroooooooooooooooooooooooooooooooooooooooooooooooo ooooooooooooooom!!!!!!

The engine went right to red-line and wanted to keep going, before I cut it off! And that’s where we are. Every time I turn the key the engine runs away with itself. I’ve had ‘runaway diesel engines,' but I’ve never had this experience with a gasoline motor. I don't even know what to call this in order to do a search on it!

Anyone have a suggestion on what to look for first?

Additional Info:

1) Throttle linkage is disconnected, so is the cruise control.
2) I dismounted the CIS to clean but re-installed it (I believe) exactly as it was. I’ve made no changes or adjustments to the CIS.
3) The engine started and ran perfectly before the refresh and never exhibited anything like this soaring idle.
4) I adjusted the valves while the engine was out, but have made no other changes, except:
5) I installed SSIs and new muffler which I doubt is causing this problem!

As always, Pelican help is greatly appreciated!

Well, a giant amount of air is getting into the system. Find the leak.

Throttle stuck wide open? AAV stuck wide open? It will be between throttle valve and metering plate or it would would be so lean it wouldn't run.

Why is the throttle linkage disconnected? Is the spring attached at the throttle body to keep the plate closed?

+1

Without the counter weight, airflow keeps the throttle open.

Good Morning JP, Ed, Pmax,

‘Find the leak,’ O.K. got it! I’ve been reading the online CIS primer and my copy of the shop manual to re-familarize myself with the system. I’ll delve into the auxiliary air valve, throttle valve and metering plate today.

The throttle linkage and return spring was in place and connected when I first started the engine and the red-lining condition manifested itself. After several restarts with no change, I disconnected the throttle linkage, just to see what would happen. I then tried to alter the throttle position with a block of wood. With all the drama and noise of a red-lining engine and the need to shut it off quickly, it was just a dumb experiment that failed.

I’ll reconnect it today, follow through with your suggestions and report back!

Thanks very much!

Look down the throttle housing to confirm the plate isn't stuck open. My bet it is. The only other thing I could think of is a hose is off or connected wrong.

Gomez, will do, thanks!

Pisca,

Another possibility is the cruise control going haywire. I have mine ziptied where it connects to the housing.

http://forums.pelicanparts.com/uploa...1566976041.jpg

all above or.....if you do have a cruise control..a lot of time the problem is...right here with those 2 Phillips head screws -has to be two washers...one regular and on spring washer.If not the screw will hit the throttle housing and stay open...
Ivan
http://img.pccreation.net/photos/201908280952219433.JPG

Good Morning Gentlemen,

Greetings Ivan, Pmax -- No cruise control connected.

JP wrote: “Well, a giant amount of air is getting into the system. Find the leak.”

That was it! I looked around and found this big ol’ aluminum elbow sticking out of the back of the air bonnet with nothing attached to it! And a hose just laying there with it’s other end connected to the oil fill pipe. So, hand me another ‘Moron Award’ for missing that! I’m collecting them these days!

Once I clamped the oil hose the engine fired up and sounded great at high idle, but unfortunately, that didn’t last long. After about 20 seconds, the engine tried to settle down, held steady for a few seconds and then started to stall. Then the RPMs would surge, drop, surge, drop, surge and finally stall. I can keep it going with the throttle lever; but once I release that, ultimately, the engine stalls. I'm thinking this may be a vacuum leak but other than that, I’m not sure what to check next.

Is it common for a Porsche motor to be cantankerous on reinstall? As mentioned, removal of the CIS for cleaning, valve adjustment, and SSIs are the only changes made to the motor. Shouldn’t it be running as smoothly as ever?

And now, please allow me a confession:

This SC refresh has taken eight months and this first restart is making me a bit nervous! Back when the engine was on a stand and I was wrestling exhaust studs, the woodruff key that holds the fan pulley, dropped as I was removing it -- never to be seen again.

At that time, the consensus of Pelicans seemed to be that woodruff keys don’t fall upward toward exhaust ports but downward toward the floor. But after a week’s worth of searching, sweeping, magnets, etc. – I never did find that woodruff key. Now it haunts me!

So this may be paranoia, but yesterday, when I was holding the throttle to keep the engine running, I started hearing a steady, rhythmic, metallic, tapping sound around the right rear of the motor! It scared the bejeezus out of me!

I shut down, checked the oil and restarted. The engine seemed to be running pretty well, but the knocking was still there. There was no smoke or other symptomatic noises. I shut down again.

So now I’ve spent a restless night with visions of woodruff keys in very unusual locations! If you have any thoughts on whether it’s safe to restart this motor, I’d certainly appreciate them!

Thanks for all your help!

Prudent course of action........
 

Robert,

If I were in your shoes, I will do the following:

1). Drain the crankcase oil and filter it for re-use. Inspect the magnetic drain plug.
2). Remove the sump plate and use a camera probe to inspect the bottom sections of the crankcase. I doubt the woodruff will be there inside. But for peace of mind do a visual inspection.
3). Use a smoke generator to test the integrity of your vacuum.
4). Measure your control fuel pressures from CCP to WCP by running the FP only. Record the initial control pressure until it maxed out. A five (5) minute test run would be sufficient. Save the data.

Prepare for another start up and keep us posted.

Tony

Thanks Tony,

I'll go down and drain the crankcase and measure the control fuel pressure now.

One thing I forgot to mention is I put regular gas in the car. When I went to the gas station to fill a 5 gallon jug, I went into auto-pilot and started filling my truck with regular and then filled up the jug. I'm not that's a big deal, I just thought I'd mention it.

Good luck man. You seem to be getting enough help already. These engines are not supposed to be cantankerous, but anytime you mess with the old CIS system by … cleaning it, it will let you know that it does not like that.

Pisca,

Don't start the motor again with the knocking. Turn it by hand to see if it's totally smooth.

About that CIS, if you haven't already seen this, a highly informative introduction to the basic operation.

https://www.youtube.com/watch?v=a4fJAfXYxWk
<iframe width="480" height="360" src="https://www.youtube.com/embed/a4fJAfXYxWk" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>

Tony,

Oil drained. A few strands of metal filings, thickness of a human hair, less than 1/2 millimeter in length. No chunks came out of the crankcase and the oil is clean.

What's the crankcase capacity? I put about 13 liters in the engine, but didn't get much out of the crankcase, maybe 2 or 3 liters. Engine's cold, of course.

Moving on to fuel pressure.

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Sump plate screen........
 

Robert,

Your sump plate should have a screen. Please confirm. If the errant woodruff was lodged between moving parts inside your motor, you won’t be able to do the cam timing after all. The warm crankcase oil is usually be between 3-4 liters. Fill oil tank with oil and this is a trick I use to check cold oil. If you have oil on the tip of the dip stick (motor not running) you have sufficient oil. After you run the motor to operating temperature, check the oil level while the motor is idling on a level ground. The oil mark will be between the two markers. Good luck.

Tony

Pmax, I turned the motor over (quite a lot) and didn’t detect any noise, hesitancy, sticking, etc. Fear of the dreaded woodruff key prompted me to rotate the engine a number of times when it was out of the car and I got the same result. You were smart to suggest I do this after hearing the tapping noise.

Thanks also for the link! I’m trying to learn as much as I can about CIS and that will help. I’ve had a number of cars with K-jetronic and it’s always been very reliable for me.

Yelcab, thanks for your good wishes!

Tony and others,

I did three System Pressure tests -- jumping the fuel pump relay and with my gauge connected between the Control Pressure Regulator and the center fitting on the Fuel Distributor. As per the Bentley diagram, p 240-10. I let the pump run for 5 minutes each time, as Tony recommended.

First Test: 43 psi
Second Test: 42 psi
Third Test: 42 psi

Interestingly, after each test, I switched off the ignition and noted that the pressure dropped to 35 psi over 5 minutes and held there indefinitely. Since the engine wasn’t running, I don’t think that’s a technically valid Residual Pressure test, but it does suggest the fuel lines are not leaking. And, I found no leaks at the fuel pump, in the tunnel, or the engine compartment.

According to Bentley that 42 psi system pressure is way too low and should be 65 – 75 psi. On my computer I found some results from 2009, which show 65 psi at that time. So, I guess a new fuel pump is in order!

Now what to do about the rhythmic tapping noise!?

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Tony,

My engine came to me with a sump plate manufactured by a company named “Mainely Custom By Design, which was purchased by “Precision Matters” in Berwick, Maine. They still sell it.

On the version I have, there is a screen I can feel on the inside left of the hole. I can get my finger 1.785 inches into the hole and then it runs into a ceiling. The screen attaches between the bottom of the plate and this ceiling. I probably extends 360 degrees around the inside of the plate, but I can only feel it on one side. I can certainly drop the plate to see what’s there, but I’d need to order a new gasket.

Also, thanks for the oil info and tips. More oil came out after I rotated the engine and pulled the plug to check for the screen. All tolled, I say it is about 3 – 4 liters, including the mess I got on my hands. :)

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FP flowrate test.........
 

Robert,

Do a flow rate test before deciding to replace the FP. If the measured volumetric flow rate is within spec., increase the shims total thickness. Do you remember removing the primary pressure valve of the FD during the rebuild?

Disconnect the fuel delivery line before the fuel accumulator. Test run the FP and collect the fuel for 30 sec. (multiply it by 2 to get volume per min.).

Tony

Robert,

Sorry to hear about your varoom issue. Guess you found a leak.

I’ve lost a few things and was very nervous about that. Managed to find most.

I can furnish a picture of the fan woodruff with a penny next to it if you want.

What is your AC doing if you have one (connected)? My right rear tapping long ago was related to my AC, sadly I don’t remember for certain how I fixed it (tightened up the mount I think). Someone said it was a bearing noise but it was not.

Mike,

Thanks for your kind sympathy and photo offer. The woodruff key disappearance happened months ago. I replaced it before putting the engine back in the car. I’m probably being over-cautious, but after all the work that’s been done, every odd noise is making my hair standing on end! As you say, losing a part like that can be tough on the nerves!

I haven’t installed my new compressor yet, so I don’t think the A/C is playing a part in this case. Thanks for the tip though!

Tony,

Good point! I’ll do the flow test tomorrow and report back.

This evening, I’ve been reading the K-Jetronic Workshop Service Manual that’s available over on Rennlist. It really is fascinating how these systems were engineered! I found the section concerning the flow test and the shims.

I did not remove the primary pressure valve on the fuel distributor. I took the CIS off the engine at the intake runners, but didn’t disassemble anything, except to change fuel lines. I took the CIS off to clean the engine and check out the devil’s triangle under the shroud. The CIS went back on the engine, exactly as it came off – well, to the best of my ability, anyway.

I dropped the engine to refresh the suspension rubber and the project grew from there. But there was no engine rebuild or work done, other than installing the SSI’s and adjusting the valves; with a dial gauge and my fancy new Stomski jig.

Thanks so much for your help!

Tony,

That was smart of you to suggest the Flow Test!

The Porsch K-Jetronic Workshop Manual states the specification as: “minimum 1000cc in 30 seconds.” I did the test 3 times and got almost twice that: 1800 cc in 30 seconds. Well above the specification.

This made me suspicious of the pressure data that I posted, which was, in fact wrong! I tested my gauge against two others I had in the shop and discovered that my gauge was faulty. I replaced it and retested for System Pressure – 3 times.

I got System Pressures of 68 psi every time. The specification for System Pressure is 65 – 75 psi. So, it seems I don’t need the new fuel pump!

I’ll do the diagnostics the manual recommends under “Irregular Idle” but I really need to determine whether to start the engine and confront the tapping noise. I ordered the gaskets for the crankcase cover and will pull that down when they arrive.

Thanks again for your help and please jump in with any new ideas!

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Misleading information.........
 

Robert,

Your post #17 is misleading. The 42 psi. is not the system fuel pressure but the warm control pressure. Was this with the valve closed or opened? I would say it was opened. Based from your flow rate, your fuel pump is good contrary to what some people claimed.

Tony

Can you measure the cold control pressure with the apparatus you have? Are there any more vacuum leaks?

My guess is the tapping noise is nothing to be overly concerned about. Doubtful it is the Woodruff key. Maybe a loose valve adjuster?

Good Morning Tony and Pat,

Pat, I think you may be right about the tapping. It's like a consistent 1/8th note beat. Maybe I'm being too overcautious. Still, the gaskets for the oil sump arrived, so I'll drip that and see what I find. I even have a bore-scope on the way, but I'm not sure I'll know how to use it.

Tony, I’m sorry for that misleading post! You’re probably right, it’s very possible I left the valve open. Still, for whatever reason, that gauge is not consistent with the others and no longer comes down to zero. So it needed retirement, in any case.

Before anything else, allow me to ask if you, Pat, or anyone, can explain what the K-Jetronic Workshop Manual means when it states:

“...Bridge the safety circuit (see Electric Wiring Diagram) ...”

The manual says we need to bridge this circuit to do the warm and cold Control Pressure test, but this has me stumped because:

On the Electric Wiring Diagram (attached below) it reads:

“911, 911S, 911SC .(since 1976) Bridging the electric safety circuit . The electric safety circuit can be bridged by disconnecting the air flow sensor plug or by bridging terminals 30 and 87a with a fused (8 amp) jumper wire “

What’s confusing me is that the diagram shows terminals 30 and 87a on component “R” – which it calls “R = Thermotime Switch”. My Thermotime Switch has two terminals and doesn’t look anything like that!

The diagram also shows component “D” – which it calls “D = Electronic Relay”. This is where I’d expect to find terminals 30 and 87a, but the terminals on component D are numbered 1 – 5.

Am I reading this wrong or is there an error here? Does “Bridge the safety circuit” really mean “jump the fuel pump relay” or is it something else? Since I couldn’t figure this out, I proceeded without knowing whether my safety circuit is bridged or unbridged! :-)

Cold Control Pressure: following the Workshop Manual, I did the cold control pressure test –

Engine cold and not running
Power cable DISCONNECTED at the WUR/FPR
Gauge connected between the WUR/FPR and the center fitting on Fuel Distributor,
Valve at the pressue gauge, OPEN.

I did the test 3 times and found the results kinda surprising.

Result: 18 – 19 psi !!

I just don’t see how that’s possible. This engine ran beautifully before the drop and NOTHING has been changed! It seems awfully strange that the WUR/FPR worked flawlessly for 40 years and decided to quit while sitting out of the car for 8 months! Maybe I really do need to ‘bridge my safety circuit?’

Warm Control Pressure:

Engine cold and not running
Power cable CONNECTED at the WUR/FPR
Gauge connected between the WUR/FPR and the center fitting on Fuel Distributor,
Valve on the gauge, OPEN.

Result: 31 psi

AFTER, the warm test I checked the voltage at the cable to the WUR/FPR and got 11.96 V

I know this is too low, but how the heck do you get 14+ volts out of a 12 volt battery? I realize that they charge to a higher voltage, but I don’t think my battery is ever above 14 v consistently. Spurious current draws and minor flaws in the system knock that down to low thirteens.

I’m going to do the test again and try to supply the WUR/FPR with 14v.

Tony, before I sign off, let me thank you for your tremendous contribution to all of us! I spent a lot of time yesterday reading archived threads on CIS, Adjustable WURs, etc. Your comments were always clear, helpful, and intelligent. I learned a lot! Thanks!

All additional comments here are most welcome!

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Pisca,
Yes, "bridging the safety circuit" means bypass at the fuel pump relay, refer to the Bentley, there's a pic. The fuel pump needs to be running for the cold/warm pressure tests. Use a fuse in the bypass just in case and when you're done, keep it in your glove box.

Sorry, can't find a good pic...

By the way, this thread has some great info http://forums.pelicanparts.com/porsche-911-technical-forum/758788-cis-troubleshooting-dummies.html

... and if you don't have the Bentley, get one. Mine is used to shreds.

11.96 volts at the WUR is normal, don’t worry about the 14 volts.

Hi Pmax,

Thanks much for that! I had a feeling that's what it meant. It seems odd that Porsche would make that kind of mistake in a service manual diagram -- mis-labeling BOTH the "D = Electronic Relay" AND "R = Thermotime Switch" !!

I'm enjoying learning more about the CIS and will check out the thread!

Timmy,

Thanks for the voltage information! I plan to re-check it, just to make sure my readings were correct and to see if it stays consistent.

So it seems that I did "Bridge My Safety Circuit" correctly. If that's so, then my cold and warm Control Pressures are way too low. It still befuddles me as to how that could happen with the engine just sitting here in the workshop!?!?

Hopefully, Tony will come by to provide his insights! And maybe an offer to fix my WUR?!?

Wrong diagram..........
 

Robert,

I saw your post earlier with the factory diagrams and noticed the mistake. I wanted to call your attention to this blunder but my wife was calling to have lunch. And after lunch, saw you have discovered the blunder and that is good.

I will give you another advise when doing this type of electrical troubleshooting. Use a 12-volt test light to test for continuity, voltage, or ground. It makes the testing easy and simple.

If you need assistance in evaluating your WUR send it to me and will do it for FREE. Just take care of the shipping and insurance costs. BTW, what are the last 3 digits (0 438 140 xxx) on your WUR? Thanks.

Tony

Robert, I think the "safety circuit" is the airflow switch. So, if the car doesn't see airflow (ie, engine not running with the key on after it has been running, the switch will shut off the fuel pumps. I think it is the 85 circuit on the fuel pump relay.

Poor or erroneous English translation........
 

Robert,

Read the highlighted sentences above “Bridging the electric safety circuit”. This should be expressed as “By-passing the electric safety circuit”.

“The electric circuit can be bridged by disconnecting the air flow sensor plug.......” the word “bridged” is erroneous and should be replaced by “by-passed”.

Let’s reconstruct the sentences and insert the correct translation:

911, 911S, 911SC (since 1976). By-passing the electric safety circuit. The electric circuit can be by-passed by disconnecting the air flow plug or by bridging terminals 30 and 87a with fused (8 amp) jumper wire.

Most of the mistakes you will find in the original factory manuals or technical bulletins were caused by German translation to English. Majority of the readers will not find the errors unless the reader/s has a good understanding of subject. Re-read the re-constructed format and compare it from the original version. Which do you think makes sense?

Tony

Good Morning Gentlemen,

Greetings Pat!

I’m sure you’re right that it’s the air-flow switch. I’m learning a lot about this stuff! The link Pmax offered is an excellent tutorial. So is film he posted.

Tony,

Thanks for your generous offer! Before I take you up on that, I’m going to re-do the control pressure tests today, just to double-check that I didn’t do something in error (always the first likelihood).

The Cold Control Pressure @ 18 psi and the Warm Control Pressure @ 31 just baffles me. I find it too strange that the WUR should fail while sitting in my shop, on the engine, idle, for 8 months. Any thoughts on that?

“911, 911S, 911SC (since 1976). By-passing the electric safety circuit. The electric circuit can be by-passed by disconnecting the air flow plug or by bridging terminals 30 and 87a with fused (8 amp) jumper wire.

No question! Your rewording is far better! Your version clears up the confusion as to what gets ‘bridged.’ That’s where I got stuck, thinking there might be another terminal 30 and 87z on some relay or component I didn’t know about.

WARNING: Abstruse pedagogy ahead, proceed at your own risk!

I suspected that the error might be in the translation to English, but it seemed odd that the translator would use the term bridging in three locations, if it hadn’t been phrased that way in the German.

Just to be pedantic about it, I turned to GoogleTranslate to find that the German for “bridging” is “Uberbruckung.” In German the word emphasizes ‘getting over’ or ‘getting around’ something. It appears to be synonymous with the English word “reconciliation.” Understood in that manner Uberbruckung seems to carry the connotation of your English word choice “by-passing.”

In English, the word “Bridging” certainly implies ‘getting over’ – but the stronger connotation, I think, is the sense of ‘connection.’ We use “bridge” to mean ‘connect one side to the other.’ The word’s connotation of ‘getting over’ seems a secondary meaning.

So the translator might have, correctly, chosen ‘bridge, bridging’ to represent “uberbruckung” – not knowing that, in English, it would lose it’s sense of ‘getting around’ or ‘getting over.’

What, to me, seems more egregious is the mislabeling of the components in the diagram. “R = Thermo-time Switch” and “D = Relay” are not terms requiring subtle translation. The German “Electrisches Relais” is correctly translated as “Electronic Relay” but it’s mislabeled component “D” when it should be component “R.”

If component “R” had been correctly labeled as “Electrisches Relais” in the original German document, it’s hard to imagine that the translator chose “Thermo-time switch” as the best English equivalent; simply by looking it up in his German/English dictionary! It’s more likely it was mislabeled in the original German document as “Thermo-Zeitschaltuhr.“

Isn‘t this fun?! Of course, it’s all conjecture on my part. I’m not a language scholar and I don’t speak German. If one our German speaking Pelicans finds himself bereft of absolutely anything more useful to do, maybe they’ll clarify some of this. ;-)

O.K. Time to go re-check the control pressures. I’ll report back later.

As always, thanks for the help!

Robert
Lower control pressure when warm is a good sign Your engine may have always operated at this control pressure and you may not know it. I believe there is a control pressure chart in the Bentley manual that you can refer to.
On my last iteration of K-Jettonic, I had nothing but a warm-up regulator and an auxiliary air valve. All the other crap was gone by this time.
I tend not to look at the translations rather I just read the wiring diagram.
Tony is pretty sharp with the CIS stuff

Pat, I was an English major, so I look at the language first! ;-)

BTW: The Control Pressure tests in the Bentley are done with a running engine. The test in the Porsche K-Jetronic Workshop Manual is done with the engine off. The manual also states that engine temp is “not important.”

Tony,

I installed a new battery in the car and re-tested the fuel pressures. No significant changes.

System Presssure (specification is 65 – 75 psi): My reading = 68 psi
Cold Control Pressure: (temperature 27 C, so specification is 25 – 30 psi): My reading 20 psi
Warm Control Pressure: (specification after 3 – 5 minutes, 39 – 46 psi): My reading 32 psi

New battery static voltage just under 13 v
Voltage to the WUR = 10.96

Should I conclude from this that the WUR needs adjustment or is there something else to check?

Lastly, IF a new fuel pump delivered 75 psi how would that effect the cold and warm Control Pressures?

Oh, and I forgot to answer your question, my WUR is a 045.

Hope you're enjoying the weekend!

Fuel pressure data...........
 

Robert,

Based from the fuel pressure data you have collected, here are my comments:

System fuel pressure within spec. but on the low side. Set it to 70~72 psi.
Warm control fuel pressure is too low @ 32 psi. Set it @ 42 psi. (Without vacuum)
Cold control fuel pressure @ 27°F (33~39) psi. Not (25-30) psi. Yours @ 20 psi is too low.

What is your WCP (with vacuum)?

What CIS problems are you experiencing now? Unless you install a good working WUR-045 the engine will never run well. I could lend you a WUR-045 that you could use and try in your motor. Send the WUR back to me after the tests. You would have the chance to see the difference how a good WUR performs compared to yours.

Lastly, a 10% increase in system pressure (68 psi. to 75 psi.) will have a very small effect on the control fuel pressures. Try it to satisfy your curiosity.

Tony

Glad to know those were useful. The link to the film is courtesy of our turbo powaa' friend, Raw' !

Fun read. English major did you say ? Typos, mislabeling are not unheard of. Confirming w/a Pelican search is advisable and a practice I adhere to. The CIS well is deep here and goes back more than a decade.

BTW the 045 WUR has a vacuum port which adjusts the CP. You can use a hand vacuum pump to test it.

Good Morning Tony & Pmax

Tony,

Thanks so much for your assessment! I may take you up on the loaner WUR! I'll send you a PM after I’m finished futzing around with this one..

The CIS problem I had with the engine running, was that the RPMs would climb to about 4,000 and then dive to about 1,000 RPMs -- climb and dive, climb and dive, climb and dive – six to ten times – and then stall out. Operating the throttle I could keep the engine running, but that didn’t stop the fluctuation. Releasing the throttle, the engine would do it’s up and down ‘death dance’ and finally cut out.

I don’t have a warm control pressure with vacuum, because I haven't run the engine since I started hearing the tapping sound. I do have a hand vacuum pump, so I’ll try Pmax’s suggestion and test with vacuum this afternoon.

When I heard the rhythmic tapping sound at the right rear of the engine, I shut it down and started panicking over the possibility that I’d just found my lost woodruff key!

As you suggested, I dropped the sump and started exploring with my just-purchased bore-scope. Exploring the crankcase, what I can see of the timing chain, and running the scope into the accessible oil return tubes – I haven’t found my woodruff key, or any obvious damage.

I’ve attached some photos taken with the Endo-scope, but they’re not very good, mostly because I don’t know what I’m doing! I don’t know whether to take the valve covers off and continue exploring with the scope – or should I call it a day, regarding my lost woodruff key??!!

Pmax,

The film was especially helpful, so thanks also to ‘powah Rawk!’

And thanks for the vacuum tip, I’m going to try that.

Glad you enjoyed the abstruseness! English major, yup. Two majors actually, graduated with honors in history. Lifelong student, which means I just haven’t grown up! :-)

Thanks to all!

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Fuel pressure check........
 

Robert,

You don’t need a running motor to do the tests. All you need is to test run the FP with the pressure gauge hooked up and a hand held vacuum pump. This is pretty common and basic procedure for CIS troubleshooting method. I am surprised you don’t know this one.

Tony

Hi Tony,

I'm still learning! I'm most familiar with the tests in the Bentley book, which are done with the engine running. The hand-held vacuum test that Pmax suggested is in the Porsche/Bosch Workshop Manual that I downloaded from Rennlist, just last week. I didn't know about it before that.

I'm going down to the shop to do that test now.

Any comments on my lousy photos or whether I should start the engine again?