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Despite having changed all the values it's still doing the same thing. As making it richer hasn't worked, I have to assume it needs to be leaner but when I looked at the spark plugs they had very slightly started to go white. Also some cylinders appear to be getting hotter quicker, though not by much time.

I also don't have the ability to see/modify any AFR tables. Perhaps this ties in with the different values I have on the tables, maybe some poor version?

I can't just keep randomly typing in values, so I am thoroughly stuck. Could it be something wrong with the physical timing of the engine?

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Well for starters you can't put MS2 settings files into an MS1 so I'd advise stopping trying to do that - you can export the individual maps from one and import into the other but you can't load the whole MSQ as they have very different types and amounts of settings.

I suspect your glowing headers are timing related rather than fuel but I have no further guesses / knowledge on this so will defer to the grown ups here who know about actual engine tuning.

I can't remember where you got to with the setting up etc. before having the engine apart, and if your VR sensor bracket has been off & on it's entirely possible it's shifted a few degrees. If you haven't confirmed the timing with a timing light on this engine as it's currently bolted together then all bets are off.

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  • 3 weeks later...

Had a break from this as it's destroying my enthusiasm.

Bought a borescope so I could take a look inside the cylinders, used it to find TDC rather than use a piston stop as I can't buy one that will work (they're all for chainsaws) and I don't want to make one.

Created a pretty crappy but accurate degree marking on the pulley so hopefully I've eliminated all the error that might be making the problem worse - though I don't think I've found the cause. The indicator wire isn't touching the pulley, it's just close enough to be accurate when viewed from different angles. I also painted the 5th tooth on the trigger wheel to make sure that was under the crank sensor when at TDC as per Nige's instructions. And because I had paint left over.

timimng.jpg.3f3cd7c6c089fe030ec5f72872ff5c5e.jpg

I've taken the whole exhaust apart, there are no blockages. I have ordered exhaust assembly paste/sealant that I didn't have before, some better clamps and I will be using new exhaust manifold gaskets. I did find the lambda sensor was not fully tightened so wonder if that could have been sucking air but doubt it, and surely that would just tell it to run richer rather than lean out (which is the most common cause of the red manifolds apparently). I am confident after this that it's not a leak in the exhaust causing my problems.

I'm going to check the valves are opening enough with a DTI gauge as that's the only other thing besides MS I can now think of. I must have buggered up the valve timing when assembling.

Could it be that the fuel pump is not delivering enough fuel, making any changes in MS meaningless as it's just going to be lean no matter what?

If none of this works I honestly have no way forward.

 

 

 

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5 minutes ago, ThreePointFive said:

If none of this works I honestly have no way forward.

It's frustrating but ultimately a Rover V8 is a very simple hector and there's only so many things it can possibly be. You'll get there - but also you don't need to keep beating yourself up about it, it doesn't help, if you're fed up with it go do something else for a while rather than make matters worse in the garage.

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  • 2 weeks later...

You have done well to eliminate two possibilities; as Fridge says when you get despondent, do something else for a while.

I once remember when I was very young, spending hours trying to start a bolt in a hole, behind the fuel pump on my Cortina. After dropping it countless times and finding that swearing didn't help, I gave up and returned in the morning; it went in first go!

 

Have you checked the fuel delivery and pressure regulator?

 

Cheers Charlie

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On 9/27/2020 at 1:24 PM, ThreePointFive said:

I now have red hot glowing exhaust manifolds

 

That is a clue ! ..................... Glowing manifolds normally indicates that the timing is a long way retarded, or, it is sufficiently retarded and is also running extremely rich.

I would go with setting TDC with a dial gauge to check the timing first ................

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  • 3 weeks later...
  • 2 weeks later...

Thanks for the continuing advice. After my last post I completely lost all motivation for any work on the car. Longest it's not been worked on in over two years and just starting to get the determination to finish it.

Haven't started it up since last time but have done some tweaking. I'm more posting to shame myself to keep going with it seeing as people are still trying to help (including the legedary BBC).

I had the rocker cover off and checked the valve timing, it looks right (or is exacly 180 degrees wrong). Nige has given me the original map to start from a known state and suggested a problem could have been a kinked/restricted MAP hose. Given that just prior to all this I had taped up the MS harness, it was likely that could have been pinched somewhere but having applied the scientific method of blowing down the ECU end and it coming out the engine end, I have eliminated that.

So, I have accurate timing marks and MS timing is matching the trigger wheel for the first time (no adjustment needed in the spark settings menu). I also have new exhaust gaskets, proper clamps and everything is pasted up. Might be grasping at straws but I want to make sure I've not got leaks anywhere throwing anything off.

I haven't checked the fuel pressure regulator as I'm unsure how - will Google. I know it's getting fuel as the return line filter is full, but at what pressure - I do not know.

 

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Questions like this help me audit what I've done.

I used a borescope camera to see when cyl. 1 it was at TDC, which was exactly when the woodruff key points at the sparkplug for cyl. 1, so just marked the woodruff as TDC and the marks are measured off either side of that using a printed timing wheel gauge that I then painted on. The pointer does meet the mark when it's TDC.

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On 11/18/2020 at 8:33 AM, rusty_wingnut said:

check every connector in the MS loom, make sure each wire and it's associated clip are pushed home properly in the housing. I had an injector not firing properly because of it.

I did have this before my engine rebuild as one injector was not firing at all (unknown to me). I've pulled off each injector connector to leave only one connected and listened for the 'click' on ignition then cycled them until all I knew all injectors were clicking on their respective connectors. Didn't make the mistake of checking them all off one connector...

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10 minutes ago, ThreePointFive said:

Questions like this help me audit what I've done.

I used a borescope camera to see when cyl. 1 it was at TDC, which was exactly when the woodruff key points at the sparkplug for cyl. 1, so just marked the woodruff as TDC and the marks are measured off either side of that using a printed timing wheel gauge that I then painted on. The pointer does meet the mark when it's TDC.

Ok, I'd say it is possible with this method you may have the time enough out to cause problems. Then,there is the situation that a lot of the RV8 timing points were never in the right place from factory. 

Ideally, set with a piston stop if you can, I made one with a long cap head bolt, a rounded off nut, and a hollowed out sparkplug...

When it runs, does it sound like it is on all 8? Quite possible to get the HT leads the wrong way round (number 2 problem after having a VR sensor the wrong way round!), This would allow unburnt fuel down the exhaust and either stink with white smoke out the exhaust or be just at the right point to light off as the exhaust valve opens = hot manifolds!

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I've checked the leads several times as I thought the exact same. They all are where the should be, but the room for error here is with the wiring of my coil packs - if I have that wrong, surely that would be the same as having the wrong lead to the wrong cylinder. However, since rebuilding and fixing the issue with the non-firing cylinder above, it's sounds sweet as F. It would barely idle before and bog when I blipped the throttle, now it's responsive and smooth (if a little bit too loud).

That doesn't prove they're not all firing but in the wrong order, and Fridge has suggested it's possible to have the spark timing 180 degrees out.

 

I will do the piston stop, I heard a welder was involved which is the only reason I hadn't.

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Here you go:IMG_20201127_123705.thumb.jpg.7a2249e0d826d6dff38f2a2c9758ed86.jpgIMG_20201127_123538.thumb.jpg.0b7dcd481f39545a23dea86a668f5160.jpgIMG_20201127_123541.thumb.jpg.edd34efc107449fb61e3641e71de729b.jpg

Not sure what happened to one of the images, but should be able to see I have some washers in there to adjust the length of the piston stop.

The nut was just reduced with a bench grinder to smaller than the thread internal diameter.

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  • 5 weeks later...

An issue emerged last week that I need to ask the V8 gurus about, and seeing as so many are active in this section, here is probably the best place to ask.

Due to a miscommunication, I didn't change the conrod cap bolts for new. I now know these are stretch bolts and should be replaced (the manual doesn't say this).

I think I can do this in-situ just with the sump off. Am I right or is this an engine-out job?

The manual says the bearings should be replaced whenever the caps are removed. I won't necessarily need to remove them, I can remove and replace one bolt at a time, and then re-tighten in sequence after - so no caps will come off, but they will be loose. Is this asking for trouble?

If I can't do it with the engine in place or need to replace the bearings, this is a big job but I am learning that the convenience of a job doesn't reduce how necessary it is.

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  • 2 weeks later...

Stupid question: do I need to use loctite on the conrod bolts? The manual doesn't say. I found the whole build suspiciously loctite-free.

I'm doing it this weekend when I have plenty of time and no distractions. Then I'll be trying out all of the little changes I have made to fix my running issues.

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Don't know about the petrols but the diesels I've built don't normally get loctite anywhere inside the engine. There's normally a bit of assembly lube or engine oil and then the correct torque.

The reason why they usually state to discard bolts is because the torque figures given are specifically chosen to provide just enough torque to stretch the bolts just enough to clamp and lock it in place sufficiently. Adding / discarding lubrication (e.g. the oil) drastically changes the torque characteristics, I'm guessing but it's probably easier to ensure it's got oil / assembly lube on it rather than rely on a dry bolt not catching somewhere and messing up the torque curve.

Edit: if I'm remembering correctly the torque figures nip the bolt up to the point of stretching and then the +90° for example is then the final bit which stretches it.

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