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Old 09-01-2020, 10:54 AM   #1
TestPoint
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Default Fifth annual diagnosis of K-jet system

Embarrassed . . .

After seven years of hobby work on the ’81 Bertone without resolution of all the issues I seized the opportunity to enlist the aid of a 30-year-old grandson currently unemployed due to the Chinese Virus.

Between health issues and frustration, I have totally ignored this car for more than 2 years. Seemed like a great time to try again. In my 60 years of working on motorcycles and cars I have never had to give up but am close on this one.

This car had been stored in a hay barn for 19 years and has never run correctly for me. I purchased it in non-running condition with 25,183 miles on the odometer. It had been in the care of a one-man oil change garage technician for nearly a year and he never got it running.

Following is this year’s diagnostic effort. If anyone cares to see further details there are about 4,000 posts on this forum to be found at: http://forums.turbobricks.com/showth...256460&page=16
. . . and at linked threads.

I would certainly appreciate the collective wisdom of this group of experts’ suggestions on what to do next.

Cold – the engine starts instantly, idles at about 1500 rpms. Responds to throttle. This would seem to confirm that ignition side is working reasonably well.

After warm up, about 5 minutes in 80-degree ambient temperature, rpms drop and it no longer responds to throttle correctly. This could be that the engine is running on the cold start injector. Fuel distributor has been commercially rebuilt. I would say ‘professionally rebuilt’ but at the moment am unsure. Fuel pressure at the CPR is about 24 cold, 50 hot on a $5 gauge with 68 psi system pressure. Close. CPR commercially rebuilt after my many efforts did not prove reliable.

Pulled two of the NEW Bosch injectors to check for fuel spray. Spray inside baby bottles was even and a fine mist with pump jumped and running.

Frequency valve was not vibrating this year. New Bosch System relay a year ago. Changed ECU. I have 2, the one that came with the car and a correct one purchased a few years ago in this never-ending saga. Don’t remember when and which one was swapped in/out but FV is now vibrating.

Once the cold start injector kicks out (I assume) the engine runs like crap. Turned off it will not reliably start.

Last year the O2 sensor was black with soot indicating running very rich. Replaced it in last year’s diagnostic effort.

All this says that the fuel distributor is not functioning correctly. Is that the next step?

Have not gotten to O2 sensor voltage reading and dwell which are about the only other things I can think of.

Otherwise taking advantage of grandson’s time by replacing the V8 245’s heater core and the XK8’s valve cover gaskets.

Your input appreciated.
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1982 Volvo 245 with a Ford 302 V8

Ford V8 Conversion Manual -
http://forums.turbobricks.com/showthread.php?t=250257

Bertone Restoration - http://forums.turbobricks.com/showthread.php?t=256460

Last edited by TestPoint; 09-06-2020 at 02:11 PM..
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Old 09-01-2020, 11:16 AM   #2
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I know you had the fuel distributor refurbed twice and "assumed" calibrated, but I didn't notice in your other thread if you ever tried a different fuel distributor. Someone on this board will have one sitting around.
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Old 09-01-2020, 11:27 AM   #3
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No, only the one.

Sure wish I could borrow one for test rather than sending this one off for another $400 vacation. Outfit that did the 'rebuild' no longer in business.
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Old 09-01-2020, 01:19 PM   #4
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These engines are very sensitive to vacuum leaks. Injector seals and any of the air guide stuff can have sneaky leaks. I would also suggest watching a dwell meter as you start the car and warm it up.
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Old 09-01-2020, 03:41 PM   #5
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O2 sensor and dwell were next up.

The sensor is not going to read anything until it gets hot. During that period the ECU should be in open loop driving the FV at about 50%.

Grandson coming up tomorrow and we will measure the sensor voltage and dwell.

Also on my to-do list is putting the baby bottles on all of the injectors. Can't think of anyway to verify calibration beyond comparing total volume of gas. Since the fuel distributer has no adjustments beyond equalizing spring tension not sure what calibration would be beyond go-no go.

Forgot to mention earlier that the FV coil resistance is about 4 ohms which sounds about right. Resistance to ground less than 1 ohm.

All vacuum lines are new or at least were put on within the last 5 years. Everything checked a dozen times for leaks.

Last edited by TestPoint; 09-01-2020 at 06:46 PM..
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Old 09-01-2020, 08:11 PM   #6
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Is the fuel distributor hole for fuel mixture adjustment plugged? There is supposed to be a plug in the hole. That is a vacuum leak if it isn't there.
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Old 09-01-2020, 08:16 PM   #7
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The bearing plug was missing when I got the car but I understand and it has had a big screw in it for years.
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Old 09-01-2020, 08:57 PM   #8
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Quote:
Originally Posted by dl242gt View Post
Is the fuel distributor hole for fuel mixture adjustment plugged? There is supposed to be a plug in the hole. That is a vacuum leak if it isn't there.
Are you talking about the hole where you use an allen wrench to adjust it?

Mine is open, exposed and never been plugged: so I should plug it?
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Old 09-01-2020, 09:13 PM   #9
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It came from Volvo with a BB sized bearing pined in the hole. The bearing is not visable.

Yes, if yours is really open it needs to be closed. I used a half inch #12 Philips screw.
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Old 09-02-2020, 12:30 PM   #10
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Quote:
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Are you talking about the hole where you use an allen wrench to adjust it?

Mine is open, exposed and never been plugged: so I should plug it?
On the V6 engines the hole being open is a vacuum leak. It will affect how the engine runs. On the 4 cylinder engines it is a bit of an air leak. But not engine vacuum critical like it is on the V6. VW used a plug with a nice handle on it. If you can find one of those at the salvage yard or new. They are nice to use to plug up the hole from debris getting in there.
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Old 09-03-2020, 08:44 PM   #11
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After a day off to replace the valve cover gasket on the Jaguar. Grandson did the work and I provided the supervision. I proudly showed him the PC based full factory service manual that I had. He showed me on his phone the 4 minute YouTube video on how to to replace the gaskets.

Today's test plan was to first disconnect the cold start injector to confirm that was causing the quick start and warm failure. Guess what . . . car started instantly without the cold start injector. Oh well . . . .

While warming up I connected an analog VOM to the 02 lead. It is new and never moved the needle.

I will do that again tomorrow.

Pulled the injectors out to go in the baby bottles. Quit when I couldn't remember the cylinder numbering plan and had to go to YouTube to remember.
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Old 09-05-2020, 02:48 AM   #12
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Quote:
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Frequency valve was not vibrating this year.
"This year"? I'm not understanding your reference.

Regardless, a non-buzzing frequency valve is a definite problem. That buzzing is the mechanism for dynamically controlling the A/F ratio -- it's what the dwell meter measures -- you want it very close to 50% (warm, idle) so that there's room for the ratio to shift in either direction when you're on the road and the O2 sensor signal tells it either leaner or richer.

If it's not buzzing because it (or the wiring to it?) is broken, then the O2 sensor could be providing information but the system cannot respond to it. I don't recall whether it's possible to get it not to buzz by adjusting the dwell all the way to 100% but in theory that would cause the symptom as well.
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Old 09-05-2020, 09:13 AM   #13
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Quote:
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"This year"? I'm not understanding your reference.
I have been working on the restoration of this car for 6 years. It has been a never ending series of issues primarily due to its 19 year storage in a hay barn. I have 4 toy cars and others to keep running and something of a life otherwise. This one has been so frustrating that I just ignore it most of the time which is the reason for the 'this year'.

The FV issue 'this year' was a dead ECU that I had swapped out some time in the past. Its buzzing at the moment.

Baby bottles installed for injector flow test today.


Last edited by TestPoint; 09-05-2020 at 04:52 PM..
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Old 09-05-2020, 11:24 AM   #14
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Do you have a wideband O2 sensor that you could temporarily install to help with diagnosis?

The O2 sensor won't generate any voltage until it gets hot. During this time, the FV runs at a fixed 50%[IIRC], plus higher %s for acceleration/boost enrichment. You can also disconnect the O2 wire (tape off the ends to prevent shorting and damage) to keep it at the fixed 50%, and then adjust the mixture screw for best idle (or ~14.3 on the WBO2).
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Old 09-05-2020, 01:49 PM   #15
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Quote:
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"This year"? I'm not understanding your reference.
Quote:
Originally Posted by TestPoint View Post
I have been working on the restoration of this car for 6 years. [...] This one has been so frustrating that I just ignore it most of the time which is the reason for the 'this year'.
Aaah. Gotcha. I was thinking of it in different terms. When dealership mechanics once asked a friend whether the Check Engine light was on steady or flashing, he said, "How about one month on, one month off? Does that count as flashing?"

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Old 09-05-2020, 03:13 PM   #16
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I have tried to read the O2 voltage after running for 7-8 minutes at 2K rpm. Still no voltage on an old analog VOM. I thought that the needle and 3.0v scale would be better than a digital one that jumps around. Maybe not.

Did the fuel flow/balance test and they are really not well matched. The #1 gets lots more fuel than #6. That is confirmed by plug #1 being black with soot and #6 so clean that you might think that it was not firing. I confirmed with a timing light that #6 is getting good spark.


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Old 09-05-2020, 05:06 PM   #17
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Quote:
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I have tried to read the O2 voltage after running for 7-8 minutes at 2K rpm. Still no voltage on an old analog VOM. I thought that the needle and 3.0v scale would be better than a digital one that jumps around. Maybe not.
You've got the right idea, but the analog meter has to have high enough internal impedance to not drag the signal down. A digital meter will definitely show you an output, but obviously if it jumps around then analog is easier to see.

It shouldn't need anywhere near 7-8 minutes to warm up a sensor. I would think maybe 1 or 1.5. (The newer heated elements warm up in 20-30 sec, but the old one-wire versions need exhaust heat.)
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Old 09-07-2020, 06:24 PM   #18
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I tried swapping the NEW #1 injector with the NEW #6 injector and got exactly the same results. That would seem to indicate that the fuel distributor is not equally dispensing fuel.

Calls in for rebuild kit or service.

Maybe this year I will not give up.

Last edited by TestPoint; 09-07-2020 at 09:23 PM..
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Old 09-08-2020, 09:03 PM   #19
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What kind of vacuum is it pulling? The B27 had poor lubrication to the cams resulting in worn lobes which low valve lift.
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Old 09-09-2020, 12:37 AM   #20
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I don't think those fuel levels are the cause of your issue. The cold start injector only fires when the ambient temp is less than ~60 iirc. At 80 ambient it shouldn't fire at all. If you are getting nothing from the o2, you have a problem. The computer sends 0.5v to o2 at all times, so even if its not hot and outputting you should have a reading there. Poor running after 5 minutes makes me wonder if the car is getting out of open loop, then hitting a wall in closed because there is no/incorrect signal from o2. With the engine warm and running at 2500 rpm you should have a nice tight wavefrom from o2. I have an old snap on vantage with graphing meter I use to check, if you can't find something else to use they are on eBay at reasonable prices.
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Old 09-09-2020, 05:40 PM   #21
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This thing has had every problem know to man. After I suspected it not starting without the cold start injector I disconnected that and from a cold engine it started just fine, ran for awhile and then started stumbling and wouldn't start from hot.

I am having problems getting the 'new' PhotoBucket to link my pictures at the moment but I have one that shows the fuel distribution dramatically different, 80% different, engine off, pump running at idle of air flow valve. The #6 cylinder is definitely in trouble. Here are the plugs demonstrating #1 very rich, #6 very lean. That is exactly what I see in the fuel bottles.

Swapped injectors, which are new, and problem stayed with fuel distributor.



I may have multiple problems but I think I will focus on getting the fuel distributor balanced at the moment. I cannot imagine what the 02 sensor is thinking with one cylinder full rich and another full lean. Suspect that rich would overwhelm lean.
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Old 09-09-2020, 07:53 PM   #22
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I'm not sure how to do this, but I'd try running a bunch of gas through the system before touching the fuel distributor. If it's been sitting for a long time, it might clean up on its own. Maybe you can run 6 hoses from the injectors to an 5 gallon fuel can, jumper the fuel pump relay, and prop open the air plate to get higher flow? Run 4 gallons through and then remeasure with the baby bottles.

Please be careful - the local craigslist has a 2001 Volvo v40 for parts $200


For the O2 sensor, it's a little more involved. The ECU/LambdaSond tries to adjust the frequency valve to get the O2 sensor to oscillate (maybe a couple times a second) between 0v lean and 1.4v rich. If the O2 sensor voltage isn't swinging, it might be the sensor or it might be ECU/frequency valve/something else.

If you want to try a cheap single channel oscilloscope, you could get one of these (or ebay equivalent):
https://www.mpja.com/200KHz-Handheld...info/35797+TE/
https://www.mpja.com/60MHz-Oscillosc...info/35886+TE/
https://www.mpja.com/9V-Battery-Snap...info/35965+AD/
Read the instructions to understand the non-obvious features.
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Old 09-10-2020, 08:09 PM   #23
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Mud buckets are your friend when dealing with K-jet fuel. I may even buy a clean, unused one.

That exactly what I am going to do but I have ordered a 'kit' anyway for use after the flush.

When the injectors are balanced I will move on to one of the many other potential issues.

Thanks for the input folks, I shall return.
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Old 09-18-2020, 07:20 PM   #24
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I'm back.

Here is my shot glass measurements of fuel distribution cylinders 1 - 6. This is at idle for enough time to fill the baby bottles to the amount needed for shot glass measurements. Shot glasses 3/$1 at the Dollar Store. Obviously, the fuel distributor is in trouble.



First thing is to get the 2 year old gas out of the tank and check for debris. Pulled the hose off the back of the pressure pump and let the lift pump suck the tank dry into a 16 gallon storage container. No trash but old gas.



Came up with new, clean and white buckets and 30 feet of 3/8" vinyl hose.



Filled the tank with 4 gallons of new gas with a bottle of Techron injector cleaner. Ran about 2 gallons of the new gas through the entire system into the clean mud buckets. The low volume into the shot glasses reappeared in 2 gallons of gas pumped through the system. No trash was flushed through.



I guess that means the fuel distributor has to come apart. I have a rebuild kit in hand and will give it a go.

Before I start ripping things apart I want to verify that the frequency valve is operating correctly and I am not sure how to do that from where I am at the moment. The coil measures 4 ohm, the valve vibrates but I cannot think of a way to verify that fuel is correctly returning through it without the engine running. Concerned about just clipping a solid ground on the connection when it is designed for 50% operation.

Suggestions?

I found an Youtube testing the FV but used an unique factory frequency driver to drive the electric operation of the valve. Gotta think about that some more.

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Old 09-19-2020, 05:31 PM   #25
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Quote:
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Before I start ripping things apart I want to verify that the frequency valve is operating correctly and I am not sure how to do that from where I am at the moment. The coil measures 4 ohm, the valve vibrates but I cannot think of a way to verify that fuel is correctly returning through it without the engine running. Concerned about just clipping a solid ground on the connection when it is designed for 50% operation.

Suggestions?
Anyone home this evening? Going to explore removing the frequency valve.
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