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All Spark and No Bark


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I've just been checking my spark settings prior to starting back up.

I found something odd, my Cranking advance Angle was set as -10, not 10 as below:

spark-settings-trim.png

What would be the effect of that? I assume nothing once the engine stops cranking and is running but it's weird that it was wrong and makes me question what else could be wrongly configured.

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Hi from one MS noob to another! had a look through your thread as yours and mine seem to be the current problem children on the forum lol. Im sure like me youve learnt alot about MS since beginning this adventure and if you want to compare notes id be happy to give you a bell. No warranty implied or intended lol.

Oh, you mention it running rich and red exhausts... have you ran it with TS plugged in and looking at where its in the VE table while idling? mine deffo had an air leak which wasnt helping. i.e. should be 30-40 KPA at idle, mine was 80 and obviously more fuel up there than down at 30-40.

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  • 2 weeks later...

Fired it up again for the first time in months. I've made multiple little tweaks over that time to try to eliminate any reason for it running lean, mostly around air leaks and reinstating the original tune (thanks Nige).

It seems that a couple of changes have resulted:

  • It runs like a pile of carp and sounds terrible - it at least sounded nice last time
  • Only one of the exhaust manifold pipes is now glowing
  • The front crank seal is now p!ssing oil

Just to prove I'm not exagerating just how red it gets:

PXL_20210513_161913426.jpg.8d98d6d2848ea32e68767a38b443cd00.jpg

The desire to give up is unreal at the moment, when the rest of the car is pretty much done I cannot start disassembling everything yet again. I want to put it on a trailer and send it off to someone else to deal with at this point, but there's no one who would do that.

Also having taken another look at the oil, I've come to a decision. I am going to take the heads off and have a look, something is not happy so I want to check my work. I think there are some potential issues causing the redness but as I'm now only getting one cylinder glowing, that does change things from before.

I think the most likely culprit is something to do with fuel pressure/volume being supplied to the injector. It only got hot when going from 2,500 to 3,000+ RPM so I'm wondering if being the last cylinder on the rail means there just isn't enough fuel by the time it's gone round the rail at high demand. As I mentioned a good while back, I took that regulator thing off the return line (not the one that sits under the plenum that you take the vacuum feed off), so I wonder if the flow is too free back to the tank.

My other guess is that there's an air leak on the injector seal as I haven't replaced those and it might be ruining the mixture.

These are all just guesses by someone who doesn't know a huge amount about engines.

Having looked at the oil, I need to take a look for damage as there are some very small shavings and they have to be caused by something. I've seen the bottom end when I did the conrod bolts, I think it's top end. I will use the opportunity to whip the timing cover off again and check the timing is correct and renew the crank seal. The oil leak is just bizarre, I must have caught the seal when I last fitted the crank pulley as it's never had a problem before. I'll also check the lifter preload as I am not confident I was as thorough with that as I could have been.

I intend to strip it down to the block in the car, I think access is good enough and there's no reason to take it out of the car but if this is just laziness and going to make things difficult, I am hoping someone will pipe up.

Long winded and boring post, but perhaps that's fitting for how I feel about this build.

 

 

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If it's only one cylinder that rules out a few things as the ECU is bank-firing the injectors. Could be a stuck injector or one that a wire has not quite made contact in a crimp / connector not quite home.

I'd doubt your fuel pressure theory, the pump can supply enough fuel to turn the air black at high RPM so it's very unlikely to be struggling at idle.

I'm not big on the mechanical side either but is it possible it could be one lifter that's not pumped up properly or something like that - there's not a lot to go wrong in a Rover V8.

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9 hours ago, Bowie69 said:

Where about are you? 

I'm in Wiltshire, near to Chippenham.

 

2 minutes ago, FridgeFreezer said:

If it's only one cylinder that rules out a few things as the ECU is bank-firing the injectors. Could be a stuck injector or one that a wire has not quite made contact in a crimp / connector not quite home.

I'd doubt your fuel pressure theory, the pump can supply enough fuel to turn the air black at high RPM so it's very unlikely to be struggling at idle.

I'm not big on the mechanical side either but is it possible it could be one lifter that's not pumped up properly or something like that - there's not a lot to go wrong in a Rover V8.

Your last point is one I'm really thinking about, particularly if the preload is wrong too.

I'm still running in the cam, so that photo was at 3,000 rpm not idle!

It definitely seems less MS-related and more mechanical now.

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46 minutes ago, FridgeFreezer said:

It's possible I could get over to you to offer a hand at some point - although no idea what I could contribute by turning up in person :ph34r:

With the amount of beer I owe you, you'd be in a coma anyway...

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I'm not sure Chippenham counts as 'South West' :D But you aren't a million miles from me either... about an hour. So, we may be able to work something out if you felt it would really help.

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1 hour ago, Bowie69 said:

I'm not sure Chippenham counts as 'South West' :D But you aren't a million miles from me either... about an hour. So, we may be able to work something out if you felt it would really help.

I'll defer to Bowie's V8 tinkering experience on this but if you're meeting up give me a shout and I'll see if I can jump in the car and pop up to get in the way :D

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2 minutes ago, FridgeFreezer said:

I'll defer to Bowie's V8 tinkering experience on this but if you're meeting up give me a shout and I'll see if I can jump in the car and pop up to get in the way :D

Hey, I just make it up as I go along... like most of us on here.

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1 hour ago, Bowie69 said:

I'm not sure Chippenham counts as 'South West' :D But you aren't a million miles from me either... about an hour. So, we may be able to work something out if you felt it would really help.

I would have to agree but they seem quite keen to be thought of as proper west country around here so you'd be very unpopular for saying that! I am looking at moving back to the Shire though, potentially very close to you, in fact. Not that that was a motivation!

I appreciate the offers, and I will bear that in mind but I think first and foremost I need to take it apart and see what it's doing mechanically. For the cost of new head bolts, head gasksets, a front crank seal, injector seals and a weekend, I think there is a minimum level of effort required of me before asking people to travel to help.

If I discover a mangled mess then I suspect my chipperness will soon change.

Ordering the parts this weekend so they'll be with me for next weekend. I'm just keen to avoid taking the engine out again as that'll mean stripping so much of the front end.

 

 

 

 

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Hard to say exactly from the photo, but one thing to be aware of is the cam is ground at an angle to encourage the lifter to turn, so the lopsided colouring could well be normal - suffice to say I have never had a V8 apart so soon after a  new cam install! 

Check your rocker clearances/lifter preloads, if the cam is wiped out, it will show there. 

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4 minutes ago, Bowie69 said:

Hard to say exactly from the photo, but one thing to be aware of is the cam is ground at an angle to encourage the lifter to turn, so the lopsided colouring could well be normal -

It is certainly less shiny/smooth than it was, not rough but definitely not new.

5 minutes ago, Bowie69 said:

suffice to say I have never had a V8 apart so soon after a  new cam install!

Yeah I thought that might be the case, can't imagine many people do things this way....

 

I'll think one of the rocker arms is very tight on the shaft, I'm going to take the assembly off to see why and check them all while it's off. I'll pull the lifters and take a look at the bottoms to see how they've worn.

Will basting it in assembly lube while it's all exposed do any harm or has that horse already bolted?

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3 minutes ago, ThreePointFive said:

Will basting it in assembly lube while it's all exposed do any harm or has that horse already bolted?

Bolted, if there is any undue wear I am afraid, but if reassembling as is, certainly can't hurt.

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