All Spark and No Bark

[mikeh501]

You can get mechanics stethoscope for a few quid on Amazon. Doubt it’s your issue though. You just tried tuning it yet?

[ThreePointFive]

Having some time off to try to rule out mechanical issues before someone comes to help me with the tuning....

I've just done another compression test and I'm getting some very mixed figures. The distribution is something like this:

Clearly something is very wrong mechanically. I keep thinking back to the issue of lifter noise and with the poor compression, I may very well have set the lifter preload wrong.

So I'm thinking about trying something but want to make sure I'm not about to ruin my engine (any more than it is). Stupid question that I know the answer to, but I need to be 100% clear what I'm doing in my head before proceeding: adding shims under the rocker towers reduces preload, removing the spacers increases it. Correct?

It's difficult to get an accurate measurement due to the shape of the heads and the lack of space, but I think the valve springs on a "closed" cylinder moved up by 1mm when I took off the rockers. I'm leaning towards there being too much preload which is putting pressure on the valves even when the are meant to be closed, which is causing a leak.

So, can I safely add another shim under the rockers to reduce preload? I'm not talking anything drastic, I have three sizes and these would be ones about 0.5mm thick. I just want to see if the numbers go up or down. The added complication is that I'd prefer to try this on one side only to begin with, due to access and the amount of time it takes to do. I can't see why it would effect the other side, but please correct me if I'm wrong.

I know I should try oil in the cylinders to see if it is the rings, but do I really want to foul up my spark plugs and brand new lambda sensor like this? Other option is a leakdown tester, but even the cheapest are £30 and I'm not sure at that price I can trust the numbers and I'd use it just once, which is wasteful.

Thoughts or am I totally stupid here?

 

[Bowie69]

45 minutes ago, ThreePointFive said:

adding shims under the rocker towers reduces preload, removing the spacers increases it. Correct?

Correct.

[Bowie69]

Also, now back at computer rather than phone that seems to add a million lines every time I hit a key.

Do try a shim, just make sure there is *some* preload on the lifters, by making sure there is no slop in the push rods.

I wouldn't worry about a few squirts of oil down the bore harming the plugs or O2 sensor, once hot they will burn off.

 

 

[ThreePointFive]

I tried reducing the preload, made no difference to the compression so it's not that. Not even going to try on the passenger side.

I've ordered a cheap and crappy leak down tester so at least I have a chance to hear where the leak is.

[Bowie69]

Tbh, for a new build, those figures aren't so bad, variation isn't terrible, and the rings need to bed in still.

 

 

[ThreePointFive]

I did wonder about that but a page or two ago people seemed shocked so assumed it was taking the lack of bedding-in into account. Those numbers are on a cold engine, too.

I'm just going to stop messing with it now, I can find nothing mechanically wrong.

[ThreePointFive]

I am so close to getting this thing MOTed, mostly thanks to a forum member that has gone beyond any reasonable expectation to help me.

However, I have a good head scratcher for a Sunday night.

I only have cold air through the heater which I put down to an air lock in the heater matrix,  some googling gave answers from on here which suggest I've totally misunderstood which pipe goes where and my problem might be slightly more serious. See diagram:

My pipe for 10 goes from the right place to the heater but I've done the return (12) back to where 4 is coming out of the manifold. That means 4 isn't plumbed back into the bottom of the radiator in any way.

I'm guessing that the purpose of 4 is a bypass for coolant while the thermostat is closed, but not sure.

I need to get 4 and 12 teed into the bottom rad hose but space is tight as I already have a connector on it for the can thermostat.

What I can do is put a T piece into the pipe where the heater returns into 4 and take that down to a second T piece going to the bottom radiator hose. I'm not going to use the pig's heart contraption so I'll have to link them further up.

 

Edited March 14, 2022 by ThreePointFive
Number of fundamental misunderstandings about the way the coolant system functions

[FridgeFreezer]

The 127 has the closest to your vehicle;

Top hose: Stat outlet to rad top

Bottom hose: Rad bottom to pump input via eBay tee piece. Tee goes off to heater matrix.

Takeoff on inlet behind alternator goes to other heater pipe.

Bleed #1 on rad goes to air bleed by the temp sensor - no plenum heater.

Bleed #2 on rad goes to header tank.

I think that's it. Anything else is likely not fitted / blocked off.

[elbekko]

11 hours ago, ThreePointFive said:

My pipe for 10 goes from the right place to the heater but I've done the return (12) back to where 4 is coming out of the manifold. That means 4 isn't plumbed back into the bottom of the radiator in any way.

Yeah, that won't work. Both of those are "out" flow, just that one is blocked by a thermostat (if you went to the "regular" setup without the pig's heart).

Easiest is probably to check a D1/RRC V8 cooling diagram to see how the old hose setup worked. But T-ing it into a hose going into the water pump should work.

[ThreePointFive]

Yeah I've massively over complicated this in my head as usual.

On the 50th Defenders the number 4 port is blanked off so it's not even required, though not sure why the host vehicle would make a difference...

I'll run the heater pipe past it, T-piece it in (haven't decided which side of the plenum), run it down under the alternator/over the timing cover and into another T for the lower rad hose.

It's very simple.

[Escape]

I didn't know the Defender 50th doesn't use the pigs heart external thermostat. I thought (assumed...) all GEMS engines were the same. Maybe there was just no room to fit it in the Defender chassis and LR had to resort to the earlier style plumbing?
The diagram in Rave for the cooling system doesn't appear (entirely) accurate. For one the fan spins clockwise, so would need to be driven by a V-belt and not a serpentine belt like on the 4.0 GEMS.

[Bowie69]

1 hour ago, ThreePointFive said:

Yeah I've massively over complicated this in my head as usual.

On the 50th Defenders the number 4 port is blanked off so it's not even required, though not sure why the host vehicle would make a difference...

I'll run the heater pipe past it, T-piece it in (haven't decided which side of the plenum), run it down under the alternator/over the timing cover and into another T for the lower rad hose.

It's very simple.

Sam, yes, exactly this, as per Fridge's set up, and mine as it happens.

[ThreePointFive]

While trying to run in the new lifters, I had interesting behaviour in MS. Holding at 3k revs, the car was almost constantly popping from the exhaust. This was not like backfires or the 'pops and crackles' of badly-modified Fiesta ST fame, but very gentle. It didn't sound right, but nor did it seem to affect much.

However, occasionally there would be a bigger event which was audible as a thump from inside the cab but not outside, weirdly. You would have to put on earphones to hear it, but you will see the pulsewidth and O2 sensors showing that something was happening. This would be once about every 30 seconds on average, but there may be a sequence of two or three within seconds.

I won't try to describe the sequence of events, this video will do that better:

 

 

Don't blame me for the filming in portrait, that was a mate who was watching the gauges as I ran around looking for leaks/smoke/fire.

When driving, there was no appreciable issue with power, stuttering or misfires.

In more general driving the car is quite keen to stall and does lose revs when the fans kick on so it needs some adjustment there. It also doesn't want to keep running without throttle applied when cold (I can see that's quite normal) but it will need light throttle to keep running after only 10 minutes between runs, as though it is starting from cold even then.

Any ideas where I should look for easy things to rule out in these scenarios?

 

 

[ThreePointFive]

It seems like I might have asked something stupid in the above post, so while I'm on a roll..

I'm trying to get a set of HT leads to replace the ones I have. I don't trust the quality as I found one had just fallen completely off. And importantly I do not want red, it doesn't fit with the standard look and on an engine making less than 200 bhp, not really appropriate.

Genuine looks to be no-go on availability as more than price, so that's out.

There's a dirt cheap, grey, application-correct set.......of Britpart ones, so naturally I am trying not to buy those.

Or there's these at £40 but Only available in RED... Because RED means SERIOUS.  So I'm trying not to buy these either. They'd be perfect if not for being too "serious".

But that only leaves me with Magnecor. at £115 +VAT, I don't think they can really work magic...can they?

I would make my own but by the time I've bought the components and the tools I'll never use again I'll be somewhere along the way towards the Magnecors.

So how important are the leads really, what would anyone recommend and why?

 

[Bowie69]

Currently using a set of 10 year old leads I put together from an old lucas set.

Working fine.

Re:stumbles.... are you seeing reset in the bottom of Tunerstudio? I think you can set up a dial to show reset counts... which may be easier.

[Chazza]

Magnecore are superb leads and they don't seem to wear out. In my experience the extra price is quickly negated by the need to keep replacing cheaper leads, which barely last three service intervals. The magenecores on my Disco have now been there for more than 100 00km. Use Iridium spark plugs as well for the best possible spark.

You ask how important the leads are! Just as important as every other component on a petrol engine. You do want the engine to run perfectly don't you?

[Escape]

You can get good quality leads from Bosch or NGK for about half the price of the Magnecors, and there not red (grey or black I think). There are different types, depending on which type of coils you're using.

[Bowie69]

Re:stalling, just open up your base idle screw a touch, you have a manual so a  slight higher idle is not so much of a problem.

I know you don't want to,  but failing that you may want an idle valve fitting...

 

[ThreePointFive]

21 hours ago, Bowie69 said:

Currently using a set of 10 year old leads I put together from an old lucas set.

Working fine.

Re:stumbles.... are you seeing reset in the bottom of Tunerstudio? I think you can set up a dial to show reset counts... which may be easier.

I don't see the reset, should it be obvious? A search doesn't show it either. On a run it's still quite well behaved but thirsty and I believe it's down on power from what I've had it doing previously.

11 hours ago, Bowie69 said:

Re:stalling, just open up your base idle screw a touch, you have a manual so a  slight higher idle is not so much of a problem.

I know you don't want to,  but failing that you may want an idle valve fitting...

 

I already have the screw set to about 800rpm when the engine is warm, I wish it could sit lower and still be happy on warm up. Adjusting it to 600 when warm makes it impossible to keep going when cold.

I have had a play and it liked more fuel and more timing advance from a cold start so I think that's onto something. It stopped hunting and smoothed right out so I think my warm-up enrichment had gone too conservative from when I last played with it in warmer weather. However, I realised it was very far advanced (20ish at idle) by the time I'd finished playing with it so I've had to back that off again. Is there any way to adjust the timing with temperature? I don't see it in TS.

I've found that I can tune everything to run quite well when it's warm, but after a proper cool down it can seem unhappy on that same map even when it gets back up to temperature. It's almost as if the ECU is adjusting things after the fact. Having put Tunerstudio on autotune and driven around, I know that any adjustment the car/ecu is seeing doesn't result in a good map.

Having looked at the differences a bit of timing made, I don't think I am on the right lines with the HT leads but I do need to bin these awful red ones once it's running well.

All part of the fun, quite enjoying it.

[ThreePointFive]

On 11/11/2022 at 7:59 AM, Bowie69 said:

Re:stalling, just open up your base idle screw a touch, you have a manual so a  slight higher idle is not so much of a problem.

I know you don't want to,  but failing that you may want an idle valve fitting...

 

I have been playing with this, the car was running very well on the first run today. It had plenty of power and seemed smoother and quieter.

However, in trying to get it to not stall so easily around idle, nothing seems to work. I have tried every combination of advancing/retarding timing and lean/rich fuel but nothing seems to make any real difference. The symptom seems to be that when the throttle is lightly/slowly pressed with no load, it will bog down to nearly stalling before rising. However, if the throttle is pressed with intent (as if pulling away from the lights), it will rev smoothly. The problem is that when doing hill starts, you need three feet to keep it running and when trying to do fine adjustment it bogs. I'm going to be driving off road on Saturday so the last thing I want is to be pegging the throttle for delicate maneuvers

Is an idle valve the answer to all this?

In more disturning, while on the motorway I pulled the USB cable out of the laptop while running Tunerstudio and the car lost all power immediately. It didn't properly cut out until I stopped but I had a very worrying wait for it to restart and then acted unhappily as if the map had changed significantly to over fuel. The ECU now isn't talking with the laptop at all despite otherwise functioning normally so I have no way to tell what's changed.

I regret saying this is all part of the fun in my last post, it just feels like this car is a constant kick in the nuts as I am not willing to put other road users (or my passengers) at risk from a vehicle I can't trust to keep running.

[Bowie69]

Where are you 4x4ing?

Idle valve won't fix the stumble on light throttle, much more likely to be acceleration enrichment, probably a touch more fuel.

Not sure what happened when you unplugged it... did you unplug from laptop or ecu?

57 minutes ago, ThreePointFive said:

The problem is that when doing hill starts, you need three feet to keep it running

Agreed, but then that is the curse of a manual off road 😛

Honestly I think I'd need to look at the map and what's happening when all this is going on, though appreciate that may be tricky given you currently have no comms.

@FridgeFreezer  may know more that, given he actually builds them, I just wire them up and tinker with custom add on circuits.

[Bowie69]

Weirdly, I got an email notification for your reply just this morning..... very odd.... given I had already responded to it!

[ThreePointFive]

22 hours ago, Bowie69 said:

Where are you 4x4ing?

Idle valve won't fix the stumble on light throttle, much more likely to be acceleration enrichment, probably a touch more fuel.

Not sure what happened when you unplugged it... did you unplug from laptop or ecu?

Agreed, but then that is the curse of a manual off road 😛

Honestly I think I'd need to look at the map and what's happening when all this is going on, though appreciate that may be tricky given you currently have no comms.

@FridgeFreezer  may know more that, given he actually builds them, I just wire them up and tinker with custom add on circuits.

Going to Bowyer's site so a nice gentle one to get everything shaken down.

Do you have any screenshots of where to do the acceleration adjustment? I have a lot of options in TS and I am now reluctant to touch too much without knowing the effect after my recent adventure to the hard shoulder.

I don't necessarily believe the laptop being unplugged was the cause but the timing was incredibly similar. It was plugged in on the laptop but the screen said it wasn't getting the feed from the ECU - which in itself is weird as it had been the whole time - and when I pulled the cable out of the laptop, it lost all power.

I have been out today and was able to connect straight in . Nothing like intermittent fault to boost your spirits... I have loaded the last known-good map but one that still has my fine throttle issue so I'll need to at least improve that before Saturday.

I didn't want to rely on other people sorting my problems out even though I did joke about getting you to take a look at it.  I now think it's essential someone who knows what they're doing looks at it! In return for suitable compensation, of course. I'll PM you for dates that work in the next few weeks.

And I can do hill starts in any other manual car! I wonder if it would even keep running if it was an auto.....

 

 

[Bowie69]

Here: 

Under 'Time-based accel enrichment'

It may be a bit different on MS1, which I think you are on.... but the main function is the same.

You'll want TPS based AE, you basically tweak the points in the graph in the top right until it starts accelerating off idle better, you can check the lambda in the graphs below while it is running and check for lean/rich when you stab the throttle and get a better feel for it. It's based on rate of change of TPS value, i.e. the faster the stab the throttle, the more it moves down the X-axis and adds more fuel.

All that said, AE, like warmup, is additive to the existing fuel going into the cylinder, so if your main VE map is wildly out of whack then there is little point spending ages sorting this out, and then tweak the VE map by autotune or whatever and then have to come back and do it all over again.

I guess the takeaway is that you really, really must get the VE map in a good state before messing with peripheral things such as AE, WUE etc. You can probably improve it for Saturday, but be prepared to do it again at some point (or for me to look at it!).

I know you had a narrow band, have you considered a wideband lambda? Much better for getting tuning done, you can swap back to narrow when it is all tuned as they are much cheaper if they get broken -that said my wideband seemed quite happy being dunked at 7S... so I'll probably leave mine until it dies.

Not wanting to discourage you, but I think at the start of my MS journey I spent as much time reading up on how to tune things as I did on building the whole installation -it is just as important, why have it if you can't make it right...

Sunday PM's work well for me, message away...