Cyl 2 and 5 lean, This is how I fixed

[Alan L]

This is your critical fitting. The ball socket end connects to the front pump supply line. There is one of these at the intake side of your rear pump. So with that fitting you can cobble enough bits together at your supply shop.
Alan

[Alan L]

OK - the thread with the non- socket end (inserted in the fuel filter) is M14x1.5.
The socket end (that fits to the front pump supply line) my best guess is M16x1.5. The 1.5 is right and I am picking M16 as right. So if you take the spare one off a dead fuel filter - or obtain one from a supply shop, the socket bit goes on the fuel line from front pump. That leaves you with a M14x1.5 male thread to attach your gauge Tee piece plumbing to. Then your hose end at the rear pump end needs to attach over the M16 (?)x1.5 male socket fitting. I didn't have anything with a socket ball fitting - I just found a brass fitting with the same thread (female) M16x1.5 at a guess. So not a perfect seal - slight leakage around the threads - but close enough.
So to get back to the original point of the post on 2/5 lean, if I was getting say even 50 (cc) flows over my balanced FD and wanted more on 2/5 I would be looking to bump them up as far as to 60 while the others read 50. Somewhere between 55-60 would be my guess. 55 is only 10% more. Those 2/5 look real lean. At worst, you would be slightly rich on 2/5 by going 20% more. But my SC manual tolerates a 10% variance in the FD flows - ie within 10%, don't need to adjust anymore. I think you are looking for something a bit more than 10% to correct the issue.
Regards
Alan

[Alan L]

OK - tried to edit - but can't. Can confirm M14x1.5 for one end and M16x1.5 at socket end.
Alan

[heliolps2]

Originally Posted by Alan L

OK - the thread with the non- socket end (inserted in the fuel filter) is M14x1.5.
The socket end (that fits to the front pump supply line) my best guess is M16x1.5. The 1.5 is right and I am picking M16 as right. So if you take the spare one off a dead fuel filter - or obtain one from a supply shop, the socket bit goes on the fuel line from front pump. That leaves you with a M14x1.5 male thread to attach your gauge Tee piece plumbing to. Then your hose end at the rear pump end needs to attach over the M16 (?)x1.5 male socket fitting. I didn't have anything with a socket ball fitting - I just found a brass fitting with the same thread (female) M16x1.5 at a guess. So not a perfect seal - slight leakage around the threads - but close enough.
So to get back to the original point of the post on 2/5 lean, if I was getting say even 50 (cc) flows over my balanced FD and wanted more on 2/5 I would be looking to bump them up as far as to 60 while the others read 50. Somewhere between 55-60 would be my guess. 55 is only 10% more. Those 2/5 look real lean. At worst, you would be slightly rich on 2/5 by going 20% more. But my SC manual tolerates a 10% variance in the FD flows - ie within 10%, don't need to adjust anymore. I think you are looking for something a bit more than 10% to correct the issue.
Regards
Alan

Hi Alan, and Turbo friends

Great write up, It maybe a little complex for some people to follow. I went through the complete system and balanced the fuel rates like you just did back in 2011-12 on my yellow 3.3 turbo. It's a lot of work but worth it to understand how the fuel system works. After all that I still ended up lean on 2 and 5, the only way to know for sure was pulling the exhaust off and get a visual, I ended up turning the adjuster on the FD about 20deg of a turn to get a balanced color through out the exhaust and even exhaust temps.

On my 965 I did not go through all the testing and balancing this time around, because my issue was exactly issue I had before on the yellow car, lean on cyl 2 and 5. I simply skipped all that and just adjusted 2 and 5 at the FD about 20deg of a turn, I hope that should be good The only to know for sure is to pull exhaust and get visual. That's my next step in a couple of weeks. It should pretty simple since everything is fresh.

Stay tuned.

Helio

[heliolps2]

Alan,

How many deg of a turn would you say would be 10% or 20% more fuel. 360deg being a full turn of course. Also when you added fuel to, lets say #6, would the fuel rate go up or down on all the other injectors? from your chart they seem to have gone up as well. Please explain what was your proses was from adjusting 6 to 1 and then 2, looks like you were chasing numbers for a while ?

[Alan L]

I was adjusting about 1/4 turn each time. Bear in mind I had just reassembled the FD from raw components on my bench. That is why I just concentrated on #6 to start. The FD had a new gasket and I expected it may take a bit of fuel flow for it to settle reliably. I was also chasing some small weeping around the injector line fittings on the FD. It all took a few runs to sort things out.
I was happy to do a few more runs than needed to make sure it was going to stabilise.
At a guess I would say 1/4 turn was giving me between around 5%.
It makes no difference to the other readings - unless the FD is maxed out - or you are not supplying enough fuel (low flow rate). You can see the 3,4'5 readings were pretty stable right thru. Never touched them.
My FD is modded for more flow but I am still near the edge of max flow for it. Which is why I looked for repeat runs showing some stability.
Given the fact this is a turbo engine and AFRs are important, personally I would not trust it just to tweek a couple of injector ports without checking. At least check the plugs sometime soon after - but I prefer to rely on calibration numbers. My engine gets a hard time, and so far never had an issue with meltdown or detonation.
Regards
Alan

[Pat RUFBTR]

Thanks a lot Alan L, great!

[heliolps2]

Thank you Alan, Great to hear that a 1/4 turn gained you 5% more fuel, I only adjusted mine 1/8 of a turn, which shouldn't harm anything, but after checking the plugs as you suggested and or pulling the exhaust, I may have to give it more fuel. Thank you for the follow up friend.

Helio

[Alan L]

I would say between 5-10% more fuel at 1/4 turn. Not exact - because I wasn't really measuring those parameters. But that would be ball park numbers. As long as you are adjusting the right way - you should be safe without calibration runs.
The problem is you can't just check 2&5. You will flood the other cylinders. (I just drained the oil because of my earlier metering piston problem - pouring fuel in). Annoying - but honestly - I would say 2-3 hrs max to tear down (remove IC etc) and do a proper calibration. Most of us even busy, can find half a day sometime - too windy/rainy /cold etc to go outside. A half day well spent.
Alan

[heliolps2]

Hey all,

Update on the lean cly 2 and 5* issue, Yesterday I went for a 250 mile road trip to see my 13 year old son an daughter for dinner, My son drove her for 30 min on county back roads and he even got on the boost in second and a little in third gear. That's my boy. Anyway , drove straight home and parked it, that's important because I wanted the engine nice and hot from they long hwy drive home before turning her off, Because I wanted to pull the exhaust and check exhaust ports color on the heat exchangers and this what I found. By the way, start to finish it took one hour and half. It went very smooth. Yay! I think I added just the right amount of fuel to 2 and 5, They look pretty balanced compared to before. 2 and 5 were white as paper before. Way too lean. I knew of this issue with air cooled 3.3 and 3.6 turbo engines, from past experience with my old 3.3 turbo 911, Simple fix. I'll check my AFR's on tomorrow. I hope this helps you guys.

[heliolps2]

The before pic,

[heliolps2]

[heliolps2]

What are your thoughts on the exhaust color? Please remember I was using a flash when taking the pictures, so it looks a little lighter in pictures. I still need to check my AFR's, a friend is using my Innovative handheld unit on his 930.

[Gianni at Pelican Parts]

Great post and documentation Alan L! Thank you for sharing this valuable information with the community

[Alan L]

Gianni, you and others are welcome. That's what the forum is for. So much valuable info shared.
Happy to pay back some.
Alan

[heliolps2]

Originally Posted by Alan L

Gianni, you and others are welcome. That's what the forum is for. So much valuable info shared.
Happy to pay back some.
Alan

Originally Posted by Gianni at Pelican Parts

Great post and documentation Alan L! Thank you for sharing this valuable information with the community

You are welcome, I'm happy to help the cause, Alan thank you as well, what do you think of the color on the exhaust?

[Alan L]

The exhaust looks good - not the easiest telling from pics. But looks quite even.
Regards
Alan

[heliolps2]

Here's a closer look at it before

[heliolps2]

After adjusting the fuel head, It seemed to be a little rich at idle as expected. I finally got my handheld Innovate LM-2 ARF tester back, not surprisingly my Idle afr's was rich, at 12.3 with the air pump and Co2 sensor disconnected. I have no cat. It was simple to adjust the afr's to 14.1, with everything still disconnected. Once I connected the air pump and Co2 sensor a solid 14.7 and made a minor idle adjustment to 1000 rpm's, all good. No drama. Win!

[heliolps2]

Here's another update using an Innovate LM-2. I would like to see a little less fuel on top, but I'll take.