350 lean on one bank, but not the other

[Fastereddie]

So, funny thing we have been talking about here.
I have been test driving mine since the swap and mine is rattling too. I did work on my ckp bracket when I had the motor out so I checked my timing. Set fixed timing to 10 and the light was showing almost 15. So I adjusted tooth offset to match it up and we’ll see if the rattle goes away. This was the timing I was running at the time. So with the 5 adv, that would have at 37btdc.


I changed to this table

And it still rattled. That should of been seeing 32btdc with the offset I had. I’m not lean either. Afr showing 13:1 when it rattles. I’m going to try the 28 table with my offset now fixed and it better not rattle with 28 degrees. I’ve always ran 91 in it but maybe I got some bad fuel.

 

[Blue85]

Tpi 350 megasquirt

• Blue85
• Aug 12, 2018

Valve rattle?

I don't remember this clatter noise in years past. Slow frequency makes me think valvetrain, but it sounds the same on both sides.

 

[Fastereddie]

Could be valvetrain. Could be exhaust leaks. I think tpi are a little noisy. I the injector clatter kind of echoes.

 

[Fastereddie]

I think my rattle is gone now. So far. I’m going to leave the timing at 28 for now.

 

[campfire]

I don't remember this clatter noise in years past. Slow frequency makes me think valvetrain, but it sounds the same on both sides.

Are you joining the diesel club now?

 

[Blue85]

If it was nearly as loud as a 6.2L, you wouldn't be able to hear the injectors clicking.

There is a small leak at one header collector in that video.

 

[jekquistk5]

That sounds like a rocker to me

 

[Blue85]

So let's say it's a loose rocker, bad lifter or cam lobe going out. What if I drive it 1500 miles?

With the exhaust leak fixed I did more tuning today and pulled a lot of timing from the problem region. Bank 1 did normal and small adjustments, but Bank 2 wanted +30% fuel in that range. I think it was actually pushing it into rich misfire, which is a vicious cycle. So I copied the bank 1 table over to both and set the ECU to control via single table. Runs pretty good actually and no knocking. I think I'm smelling gas above 3000RPM, so it may be one hole misfiring. The noise is certainly not getting worse - if anything less noticeable.

I guess I need to pull the valve covers, but this is sort of my last day to work on it.

 

[Blue85]

Could be valvetrain. Could be exhaust leaks. I think tpi are a little noisy. I the injector clatter kind of echoes.

They're actually Ford injectors. You can hear them when the hood is up.

 

[campfire]

If it was nearly as loud as a 6.2L, you wouldn't be able to hear the injectors clicking.

There is a small leak at one header collector in that video.

I dunno...loud engine + smelly exhaust + valve clatter? Sounds diesely to me.

 

[dyeager535]

So let's say it's a loose rocker, bad lifter or cam lobe going out. What if I drive it 1500 miles?

Anecdotally, I broke a rocker stud in 2004. Couldn't see that anything else was wrong. Pushrod straight, rocker undamaged, cam lobe looked fine, just had to replace the studs.

Never really put two and two together, but always had a bit of clatter after that. Pulled engine out two(?) years ago, and pulled the retrofit roller cam and lifters before I sold the block. The lifter from that stud had a bent pushrod cup. I never did notice any ill-effects on economy, seems to be the same with the new motor. It may not have been affecting the cylinder significantly, but it certainly wasn't "right".

 

[Blue85]

Pulled the valve covers and was pleased they are so clean inside.

Cranked the engine with the starter and everything is moving normally.

 

[Blue85]

Valvetrain

• Blue85
• Aug 13, 2018

On the DS bank the rear 3 valves make a little noise when I put my stethoscope nearby, especially when revving, but nothing I notice with my head over the engine. Almost seemed louder with the valve covers on. Of course revving is messy.

Not hearing anything from the pushrod ends or the fulcrums.

I don't understand what's going on, but I'm going to drive it. Anything else I should do before the covers go back on?

 

[FAB454]

Best example i have: Had an avalanche come in a while back with fuel trims maxing out on one bank. I could still get it to switch but just wanted to pull things rich. All the tests I did nothing came solid conclusive. Finally bit the bullet and broke free the rusty o2s and swaped them.Rich condition followed the O2.

 

[Blue85]

So I did drive it on the UPO2018 and it worked fine. Nothing seems to be getting worse. Now I can try to figure this out without schedule pressure (you know, intend to work on it, but never do ).

I'm tempted to jump into a valvetrain swap, as I've always wanted a better cam in this engine, maybe pull the heads, but I'm trying to keep it simple for now. Since I'm going through the ignition system anyway, this is a good time to move away from the custom plug wires. Ford EDIS wires clip onto the coils and have really long boots on the plugs. I've been converting some to a standard GM-style angle boot for some of the plugs where the long boots would hit the headers. I want to get back to a standard SBC wire set that's available everywhere. I've picked up 2 Dodge 4-cylinder coils that have standard towers on them. I had been thinking that with wasted spark a bad coil had to affect both banks, but it is conceivable to get an internal winding short closer to one tower.

I also plan to swap at least one of the O2 sensors and then see how everything runs at that point.

Should I try to reset valve lash? Is it time well-spent to put a dial indicator on the valves and see how far each one moves? Or is it easier to pull the lifters and just inspect parts?

 

[jekquistk5]

Ls swap

 

[Blue85]

Of course! It's kind of on the radar to get an 8.1 for the tow rig, which frees up a 6.0. But not anytime soon, I think....

 

[Blue85]

I know you've all been on the edge of your seats...

Here we are 4 years later and I've wheeled this thing over half the trails in the local counties and it's been just great. My conclusion was that there's a software error that does math wrong for the 2nd O2 sensor. After I switched it to run off a single O2 sensor (measuring only one side of the engine), it has worked fine. I *should* update the firmware and try to correct the problem, but it's not very motivating when the thing runs fine. Plus, if it wasn't fixed in an update, I'll have to review and update the code myself, which is not my biggest strength, so it will take a lot of time.

That being the answer, I don't see how anybody had much chance to diagnose it correctly. Sorry.

That being said, I did put an 8.1L in the tow rig (https://ck5.com/forums/threads/quadrasteer-8-1l-suburban-tow-rig.339146/), and then sold the LQ4 because I was moving. In hindsight, I kind of think the SBC with custom EFI, Ford ignition, crank trigger, TPI is kind of cooler than LS swap, because nobody else has one.

I should make a build thread...