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 1.4 Energy emissions/mixture (and a thump in the night )
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Alex C
Level 6 User

Joined: 20 Jun 2004
Posts: 155

Posted: Wed Sep 08, 2004 11:18 am

Hey all
Got a quick question about my fuel air mixture - I've just had my 89 R19 TSE MOT'd, and the place I went always seems to give you a computerised emissions test sheet (even though I've no idea what the emissions limits are for a carbed car that old), and it came out with the following figures:

CO (% vol) = 2.75
CO2 (% vol) = 10.03
HC (ppm vol) = 592
O2 (% vol) = 4.03
Lambda = 1.139

Now since the Haynes reckons on 1.5%ish for CO, I'm wondering (well I have been for a while) whether the mixture is a bit arse about face. Chris H suggested a while back to me via email (before I found this forum!) that the car was probably running rich - the idle is a bit wierd, in that if I cruise on the motorway for a bit then drop to idle, the idle speed will be raised quite high - it used to be up to 1300-1400rpm at worst case, but i've lowered the idle speed since then as it was idling at 900-1000rpm most of the time. However, the high idle remains, with the high-idle-after-cruise gradually dropping down over a few minutes back to normal(ish) idle. The car also tends to hesitate on heavy acceleration, which may or may not be related. I'm only getting 35mpg round town driving very gently, and the car struggles to get much above 40mpg on the motorway even with Optimax in it and with just me on board (and I'm pretty average weight wise), so I'm figuring something is not as good as it might be regards the fueling. No offence to Chris, but since I haven't had a chance to fiddle with it yet, I thought I'd post for anyone else to suggest stuff!
So the question is - which way do I turn my mixture screw to 'fix' the mixture, and is it worth doing? And if it is worth doing, can someone please recommend a tool for the job - all the tool combinations I've tried so far have been crap for this particular job. Its an Energy engine, so the carb is squeezed between the bulkhead and the engine block, with the mixture screw being right down and under the head of the carb (as you people with an Energy will no doubt know!).

The other thing I thought I'd ask you experts is for advice on this goddam thumping noise/vibration I've got at the front end somewhere (I think). The rear brakes were arse and I replaced the drums, shoes, all the springy crap and auto adjusters, and both wheel bearings (since they got buggered trying to get the drums off), and some of the noises have lessened. The remaining noise and accompanying sensation seems to be coming from the front somewhere, and you can feel it through the floorpan under the pedals with your feet when its bad; I think you get a thump every revolution of the wheels. It's by far at its worst at around 15-20mph, and you get it whether you are in gear or neutral the same amount. Its a very low frequency noise, a dull thumping, kind of like when your neighbour bangs on the walls with their fist cause of your loud party Wink
The most annoying thing is that it doesn't happen always, and not always to the same extent. It also happens more on a right hand turn (when its happening). I've had the CV joints checked, and I've had a good look and feel of them myself, and I have to say that even as untrained as I am in these things, I can't feel any vibration coming from around the joints or driveshafts, and I can't hear anything coming from them either. I did find that the off side hub nut/wheel bearing was strangely loose and wobbly, which I took to a proper mechanic to check and who just tightened it up (the wheel bearing are only about 2 years old, and the car does low mileage, and the noise I'm getting is totally different to the knackered wheel bearing noises, so I dont think its bearing related). This seemd to make the steering very 'feelsome' in that it felt like the steering column was in direct connection to the engine block, especially on right turning, but this has lessened back to normal since I had it tightened a month ago (whether this is a good or bad thing I don't know). Everything else on the hub carriers seemed OK when I checked it, but then on that particular day, the noise wasn't too bad (sods law I guess). The only clues I have are the occasional clonking from the front end when I do heavy braking, and similarly occasionally a clonk when I start a right hand turn (just one though on each right turn, like one per U-turn kinda thing), the fact that the steering wheel still vibrates at 80-90ish quite a bit, I think a bit more when accelerating than when decelerating, and that there is quite often a small clonking sound as I lift the clutch pedal and the drive engages and also when I try and change gear at high engine speeds. The clutch pedal is also acting wierdly but I think this is unrelated - it starts off quite stiff (well its usual stiffness), then it will suddenly and spontaneously go very light and springy, and then will go back to 'normal' when it feels like it, or when I leave it to cool down for a couple of hours. The only thing the car failed on in the MOT was the front flexible brake pipes which were knackered, but then I doubt that their suspension and drivshaft checks are even vaguely thorough.

Your advice and suggestions are all gratefully received! Very Happy

PS: Has anyone got a good bodge for the central locking in the boot? My locking motor has shagged its connection to the lock barrel (as I imagine many other peoples have).
Alex C
Level 6 User

Joined: 20 Jun 2004
Posts: 155

Posted: Thu Sep 09, 2004 5:11 pm

Ahhh cmon someone must have an opinion or suggestion!
If you are of the opinion that the thumping is driveshaft related (which I am cause of the 1-thump-per-wheel-rotation), then can someone give advice on how to narrow down where the hell its coming from to either a specific driveshaft which has a knackered CV, or some other component. If its one of the CV's, then I assume its a new driveshaft (which I assume comes as a one piece thing, gaiters grease and all). Is this a majoro pain in the arse to change, or is the job relatively straightforward? Could the noise be coming from something inside the gearbox, bearing in mind that it disappears on turning left, and gets worst turning right, and that it varies in volume\intensity depending on weather (worse in the cold/damp).
The only other thing that occurred to me is that some part of the steering assembly may be knocking against something when I turn right due to failure of something or other, but the steering wheel doesn't seem to be a focus of the noise - it feels more like its someone gently knocking on the floorpan from underneath with a mallet or summink. Again if anyone can discount this as a possibility, or suggest a quick n dirty way to test for it, it would be much appreciated.

As for the fuelling question - surely I should be getting better fuel consumption, and lower CO than I have, but I have only given the carb a brief clean out using largely carb cleaner spray - could the carb be eating fuel somehow due to a fault? Would the mixture generating CO of 2.75% be likely to be enough to make a significant difference to fuel consumption? Anyone got a good tool/socket set which makes getting and turning the mixture screw easy? I want to have a go at tweaking it, but finding an appropriate tool is a major headache for me!

Hope someone can help me - the noise is driving me nuts, as is not being able to find a decent tool to get to the mixture screw! Sad
JB
Mr Quoter-vator

Joined: 16 Feb 2004
Posts: 7405

Posted: Fri Sep 10, 2004 12:11 am

it does sound like driveshafts...i have a tired driveshaft...makes a rapid knocking noise when i go round a bend under load...not in a straight line but that may be just cos it less worn.

does it make a worse noise if u go round a corner with your foot down?..i cant feel any play or anythng in my shafts/joints by hand but they definately make a noise round corners...

new ones are about 40quid gsf and shafts inc both CV joints as one unit.
Alex C
Level 6 User

Joined: 20 Jun 2004
Posts: 155

Posted: Fri Sep 10, 2004 2:12 am

Hi - thanks for the reply. Smile
The wierd thing is that it doesn't seem to alter the sound at all whether you are in neutral or accelerating, or coasting in gear. In fact, it seems louder in neutral or in gear with the clutch down, but I think thats just cause the engine noise is much less in these situations. The right hand driveshaft has a fair bit of engine oil on it due to an earlier engine oil leak, so could this have shagged either the inner CV joint or the gearbox joint on that side? None of the CV gaiters look at all dodgy, and there doesn't seem to be any greasy mank coming out round the gaiters or nything nasty like that, which is just confusing me more! The only other thing maybe worthe re-iterating is that when taking up drive, it feels like something is shifting slightly in the transmission somewhere, like something is looser than it should be - could this be related, or just a worn mount/clutch or something else entirely?
What about things that could be fouling the driveshafts on a right turn? A possibility? If so, what kinds of things might do it?
Otherwise, could anything at the back end be making this kind of crazy noise? I know cars are horrendous at carrying noises around them, so I'm open to suggestions on that too. Like I said, all the back brake assembly and wheel bearings on both sides has just been replaced and it got rid of the grinding and dodgy brakes, but not the thumping. The shocks look OK - a bit worn but not making any dodgy noises when I bounce the car.

As always any suggestions welcome! Smile

PS: Can you describe the noise your car makes from the dodgy CV joint when you go round a corner Johnnyboy? Is it a dull thumping, maybe like someone stomping about upstairs in your house on a carpetted floor? My thumping sound is accompanied by a pretty strong pulsing sensation you can feel through the floor pan too, and I don't know if this is consistent with a CV joint or some other 'shaft component/joint.
JB
Mr Quoter-vator

Joined: 16 Feb 2004
Posts: 7405

Posted: Fri Sep 10, 2004 6:19 am

when i turn right and put the power on i get this knockin noise as if someone is in the engine bay hittin something solid with a hammer rapidly. so its kinda dull from inside but not as dull as ur description of someone upstairs

...and i can feel it too...not a lot tho, but mine is only just starting to make this noise. also of course the knocking is more rapid the faster the car is moving.

does yours make it all the time? or just when turning one way?

if u jack the wheels up and spin them by hand can u hear/feel it then? have a look underneath while the wheel is spinning to see if anything obvious is knocking.

maybe its something in the brakes...loose components, bad discs, or it maybe somethign inside the gearbox itself.
Alex C
Level 6 User

Joined: 20 Jun 2004
Posts: 155

Posted: Fri Sep 10, 2004 10:44 am

It happens when I turn right - sometimes, when its bad, it happens less so when going straight ahead, but always stops when I turn left. The crazy thing is the variation of the noise - like today, I went out in the morning and I couldn't hear or feel it at all, then this afternoon it was back but not too badly. The other day it was really loud. The only commonality seems to be that if I leave the car without driving it for a couple of days, the noise has gone when I first start driving, but comes back at after a variable amount of time. It's really wacky this - its like the problem lies in something that gradually 'settles' when you don't drive the car and temporarily fixes the sound. I have spun the wheels on both sides when the cars off the ground and they dont seem to make any sound or vibration, so that made me think it was suspension related (along with the fact that it sometimes clunks when I'm turning while driving over an undulating road surface - like on some streets when you turn onto them from a side road, you go down into the gutter and then up onto the road proper if the camber is strong). However, I can't see anything loose or broken on the suspension, and if you bounce the car when stationary you dont get any thumping noises. Also, if its suspension related, it would have to be something that would be rotating or whatever in time with the wheels, since the noise speeds up when the car speeds up and has an even spacing between thumps. The only thing I can't test is bouncing the car while the wheels are spinning, since I don't have access to a rolling road thingy. I guess I'll have to ignore it until something drops off - hopefully it won't be a wheel Wink My only other thought re. it coming from the gearbox is whether the gearbox mounts could get buggered and leave the gearbox prone to thumping when turning one way in time with the driveshafts' rotation - dunno if anyone can shed any light on that theory.
By the way, I wanted to check one thing - if the thumping is driveshaft related, and only happens when turning right, which shaft is most likely to be the culprit? If it's a CV, is the outer or inner one likely to be the source? Someone explained it to me before, but it was a while back and my memory isn't all it should be Confused

Cheers

Alex
JB
Mr Quoter-vator

Joined: 16 Feb 2004
Posts: 7405

Posted: Fri Sep 10, 2004 11:04 am

sounds like a CV joint...u cant get the joints seperatly, you just get a whole shaft with joints either end...

just figure out which side is it by listening....get someone to sit in the middle of the back seat and see if they can judge what side it is....

grab your engine and see how much u can shift it to see if the mounts are shot, also watch your gearstick when goin on and off the throttle and see how much that shifts for mount wear.
Alex C
Level 6 User

Joined: 20 Jun 2004
Posts: 155

Posted: Sun Sep 12, 2004 10:26 am

Lol - I've already asked a bunch of my mates if they can decide which side the noise is coming from and they were all rubbish at it so I guess I will have to try and recruit some more noise-listeners. Might have a go myself if I can pursuade an 'older person' with all-vehicle-tp insurance to drive it while I pleb about Very Happy
Regards the mounts, I did try grabbing the engine and it didn't seem to budge, but then I'm no bodybuilder. The gearstick does rock a little, but only as much as it always has - maybe an an inch back-forth movement of the knob in total, and only if I cane the engine then pull my foot up sharpish. It does jerk when you accelerate a bit in normal driving, but only like a cm or less. The front engine mount may be a bit dodgy, just looking at it, since the radiator burst on the previous owner and the subframe under it is a bit manky and rusty as a consequence of it not being cleaned up afterwards, as is the bottom of the front mount. Having said that, I still can't move the mount sideways, and I can't feel any looseness in the up-down direction but then I doubt that means much due to its mankyness. Could the front mount knock vertically on right hand turning in your opinion(s)? If it needs changing, do you have to support the engine while changing it, or are the other mounts strong enough to hold it temporarily while the engine is not running?

PS: Still seeking a decent carb mixture screw tool Very Happy - the best I have been able to do so far is a wacky (and wobbly) 5 part socket monstrosity, but keeping that in the screw head is a total arse.

Thanks for your input!
Chris H
Forum Moderator

Joined: 02 Mar 2004
Posts: 19978

Posted: Mon Sep 13, 2004 8:45 am

have to say that these long messages made me bored so didn't read them all.

Mixture is way to rich like I said before. Screw it in to weaken the mixture, use a small stubby flat screwdriver to do this.

Assumign the engine is in other wise good mechanical health and the igntion system is up to scratch the readings should drop to around HC 200 ish, HC 1-1.5 ish Co and the lambda will move closer to 1.

Yes this will make the car drink petrol it will also cause high engine idle speed when the engines warm aftyer a long run even more so after a long high speed run and it will also cause flat spots as well.

I also suggest you look at the engine mounts, they will be knackered if they are the originals so best get them replaced, the rear is a bastard but the 2 front mounts are easy changes, front drivers side shoudl take about 15 mins and will be about 15 quid the front passenger side is abotu 15 quid and might take you up to 1/2 hour depending on the toosl availabe to you. You need 16mm spanners and sockets btw and a jack to support and lift the engine up. Just leave the car on the ground on its wheel as its far easier and quicker that way.

Rear mount is about 40 quid and best going to ren for it its also a total bastard to change, it either gones in straight away so its a 45 min job or its an arse and takes about 3 hours, normally its the latter.

Dodgy mountings will increase noise into the cabin, feel through the wheel and pedals and clunking on accel and decell.

The driveshafts may be doign this and tbh I think thge loose hub nut has killed that bearign off as well.
Alex C
Level 6 User

Joined: 20 Jun 2004
Posts: 155

Posted: Mon Sep 13, 2004 9:32 am

Hey Chris - cheers for the reply. I'll definately have another go at the mixture. The car has been run on leaded, LRP, unleaded and optimax, so I guess this combination might have worn the carb a bit and made it run too rich. I suppose thinking about it, optimax will probably make the problem worse since its supposedly more dense. When I've got a clear day or two to spare I'll probably dismantle it and replace the gaskets.

Regards the mounts, any idea how long/much a Ren garage would take/charge to do the back one? Do they have special Ren tools to do it quicker (and therefore cheaper) than regular garages? Advice on the best/safest place to jack up the engine to do the others would be appreciated too.

I thought the OSF wheel bearing (which I assume you were refering to) would have gone too due to the loose hubnut, but I had a garage check it and it seemed fine to them. Also, I'm not getting any of the grinding noises I got when the bearings went before (not yet anyway) - any tips on testing a bearing? I was thinking to just check for oil leaks and loosness, and the spin-and-listen test.

About the clunking noises - the sensation that goes with them is most obvious through your shoes and the floorpan; I can't feel anything from the thumping through the wheel. Dunno if that means anything mind.

Sorry for the long and boring messages Sad Keeping things concise has never been my strong suit.

Cheers
Alex
Chris H
Forum Moderator

Joined: 02 Mar 2004
Posts: 19978

Posted: Mon Sep 13, 2004 9:52 am

what fuel you were running the car one should have really made no difference to the mixture its the ignition timing which affects that. Just run it on normal unleaded.

its 1 hour labour for all the mounts but the rear will take longer so they will charge you more.

I would do it myself, its easy enough just a pain due to access.

Anyway frnt drivers, get under it and take the nut (16mm) fully off along with the plate, move them somewhere safe, from the top in the engine bay undo the 2 16mm nuts that hold the mount to the engine bracket, again take em right off and store them somewhere safe.

Then get a jack use the cars or preferably a trolley jack, put a bit of wood on the cradle of the jack but it on the sump close to the front corner, jack it up so the engine bracket clears the mount.

You can now lift the mount out and throw it at the cat. Stick the new one in first put some copper grease on the threads to ease future removal.

Lower the engine down onto the mount and refit the nuts. Job done.

Gearbox side, under neath remove the 16mm nut you will need a socket preferably a deep socket for this. Its just a nut with an inbuilt washer, again put it somewhere safe.

Then its a case of you can either remove the moutn and brqcket from the box or just the mount. I would remove the bracket but sometimes the bolts don';t shift of they do by snapping. So I would just remove the mount from the bracket, you need to use the spanner on this. Removing the arch linder and turnign the steerign all the way to the left helps here btw, undo the nut, this will take time as you can only turn it so far.

When the nuts off jack the box up again use the wood block on the cradle and lift it high enough to clear the mounts studs.

Then stick the new moutn in and tighten it all back up.

bearings are funny things, the one on the white 19 muy mums now using has no play and no roughness etc but over 60 it makes a racket you wouldn't believe.

it might be shafts etc but I would replace th emount first and see what happens.

Dodgy mount also make the shafts sit at funny angles causing problems.
Alex C
Level 6 User

Joined: 20 Jun 2004
Posts: 155

Posted: Wed Sep 15, 2004 10:36 am

Hey guys
Just thought I would let you know that I found the cause of the thumping noise, but I'm not quite sure what it it was. I got both rear tyres replaced, the fronts moved to the back, and the new ones on the front for the MOT, and since I got it back, no noise! A while back I had got a rear tyre puncture repaired, which I had totally forgotten about, and so I'm putting it down to that not wearing evenly with the rest of the tyre and making the noise. I thought it was coming from the back ages ago, but recently it has sounded much more 'fronty' - I guess thats cars for you; noise just bounces around. Stupid of me not to think of the puncture tho Neutral
The occasional clonking does still occur, so I will attempt to do the mounts, or at least the worst looking one (the front RH one) when my wallet has recovered from getting the car through the MOT. Had to have the front flexi brake pipes done, but the pipes from the master cylinder to the flexi's had buggered nuts, so I had to have them made up and put on, plus 2 new tyres and a back box so £100 for the metal and flexi brake pipes at a garage, and then £80 for the 2 GT3 goodyears balanced and fitted (not bad I thought) and £53 for the exhaust rear box fitted. By the way, does everyone with an Energy engine find that their backboxes always get holes towards the front of the box section? My backboxes always seem to hang down at the front which seems to shag them extra quick Sad There seems to be a long way between mounts on the rear section though, so maybe I'm missing one - there seems to only be the rubber hanging mounts at the very back, then nothing else on the back section - it just seems to attatch to the mid section and thats its only support.
Regards the adjustment of the carb - I have a selection of stubby screwdrivers, but none of em are stubby enough and wont fit between the bulkhead and the mixture screw as there seems to only be about 6-8cm available. Do you reckon that this one http://www.tooled-up.com/Product.asp?PID=10391 or http://www.tooled-up.com/Product.asp?PID=24602 would be short enough, or do you have any other recommendations?

Cheers
Alex
JB
Mr Quoter-vator

Joined: 16 Feb 2004
Posts: 7405

Posted: Wed Sep 15, 2004 1:18 pm

get one of those cheapo kits that have a load of different bits in them, like the sort u get for 2.99 from petrol station, then u can put one of the screw driver attachments into a socket and use it with a small ratchet to fit into the small gap
Alex C
Level 6 User

Joined: 20 Jun 2004
Posts: 155

Posted: Wed Sep 15, 2004 1:36 pm

Been there, tried that Very Happy It seems that both the cheapo screwdriver kits I have have bits that need some wierd socket in between 6mm and 7mm which none of my sockets are Sad Also, it seemed to me that you need about 2-3cm of a horizontal extension to get out from the screw head to a point where the perpendicular ratchet bar can move without fouling the carb, which is too short for an extension bar as far as I know. I have a 1/2" drive to 6mm socket adaptor, but I can't find a shop that will sell me a proper 6mm slot screwdriver socket instead of the wierd "somewhere-between-6-and-7mm" size. It seems that the Energy engines have the carb which is the biggest pain in the arse to adjust out of all of the 19 engines Sad
JB
Mr Quoter-vator

Joined: 16 Feb 2004
Posts: 7405

Posted: Wed Sep 15, 2004 11:58 pm

the somewhere between 6 and 7 is 6.35 which is 1/4" but as far as that little bit of extra reach is concerned thats just bad luck...there may be things available but you'll have to go hunting for them....or making things
Chris H
Forum Moderator

Joined: 02 Mar 2004
Posts: 19978

Posted: Thu Sep 16, 2004 4:37 am

I don't have any troubles and I have large hands.

break the tamper proofing off then try adjusting with your fingers.
Alex C
Level 6 User

Joined: 20 Jun 2004
Posts: 155

Posted: Thu Sep 16, 2004 10:17 am

Ok managed to move the screw with my fingers, I think with the tamper proof cap still on cause I couldnt get the bugger off - I assume thats what the yellow plastic bit round the screw head is?
Anyway, I've found a point where making the mixture richer raises the RPM, and making it leaner lowers the RPM, and if I keep screwing it in (making it leaner) will keep dropping the RPM. So I assume I'm at the 'ultra-lean' end of the spectrum. However, I have tried turning the screw the other way to richen the mixture, and the RPM just stays where it is - it feels like I'm gonna unscrew the screw; do these screws have a safety stop thing on em to stop you accidentally unscrewing them? I have been turning it 5-6 turns from the 'ultra lean' point and it has made no difference. I was expecting to find the point where the RPM starts to drop again, but it just doesn't!
Advice would be welcomed!

BTW I have tried driving it a bit, and there are no flat spots anymore, but the acceleration seems generally to be a bit limp (as I assume is expected with a lean mixture).
Chris H
Forum Moderator

Joined: 02 Mar 2004
Posts: 19978

Posted: Thu Sep 16, 2004 11:30 am

the screw will fall right out if you keep going.

Do the adjustment when the cars hot.

Also rev the engine hard every few seconds or every adjustment to clear the manifold.
Alex C
Level 6 User

Joined: 20 Jun 2004
Posts: 155

Posted: Thu Sep 16, 2004 11:51 am

I did do it when it was hot - I drove it round for 20 mins, then left it idling with the bonnet up until it cooled down enough to stick my hand round the back of the carb. I did rev it to 2500rpm for 20-30secs every few adjustments I made to the screw.
I remember you saying in another post that some carbs are very sensitive and some aren't, but I was wondering what kind of range you generally see on E6J carbs. I mean, how many turns should I expect to have to unscrew the screw to get it to the point where the idle speed starts to drop off, starting from the point where screwing the screw IN more starts to drop the RPM? Is it usually a couple of turns, 10 turns, or what? I just really really really don't want the screw to come out while the engine is running, as I imagine this is a very bad thing Neutral

Also, thinking about mounts - does anyone have a pic of a 'good' front RH mount? Looking at it again today, it looks like some part of it might be missing. I'll get a photo of mine if anyones interested.

Cheers
Alex
Chris H
Forum Moderator

Joined: 02 Mar 2004
Posts: 19978

Posted: Thu Sep 16, 2004 11:55 am

well see the pic in my megane progress report, thats a bad one!

Usually 1/2 turns and its changed.

You shoudl take it off and strip it down, might be a lot of bulit up laquear behind the screws so its not changing it.

Or it may have snapped which i have seen a few times.
Alex C
Level 6 User

Joined: 20 Jun 2004
Posts: 155

Posted: Thu Sep 16, 2004 1:24 pm

Hmmm yes I think the carb may be a bit arsed up in that case. It definately doesn't make any appreciable difference to the engine speed with 1/2 a turn, except when at the lean end of the scale screwing it in. I think the gasket may be buggered since there seems to be oily crap down the back of the bottom part of the carb Sad Can you buy the gasket separately? If so where is the best place to get it? Are there any other bits that should be replaced when overhauling the carb?

I had a look at the mount in the pics of the megane project, but tis a bit hard to compare to mine - I will get a piccy of my one up online soon.

Cheers
Alex
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