struggling for power

for some reason the four cylinder engines suffer with exhaust valves burning out,usually cylinders 3&4 (IMO),Hermione's went at 35000 mls, the main problem i had was finding replacement valves, i was quoted ridiculous prices (£38 each!!!) and a 3 week wait, i found 4 on ebay,got them for £16 for 4, result or what :laugh:,this means that i have 3 spare valves that i am willing to donate to a good cause,pm me if you need them,.........head gasket set will set you back £34 from Gaskets for Classics on ebay,...as for scrapping it for the sake of a couple of valves.... :angry:
 
I can't imagine that with those compression figures it would "run on three cylinders". I would expect a much lower reading with a burned valve. If it was mine, I would try a valve adjustment to see if running improved.

Dick West
 
I agree with Dick, those figures aren't too far apart, you could try re-shimming the valves as a start. Head gaskets aren't expensive and it's not a big job to pull the head off to re-grind the valves, but do this before re-shimming as it will affect the clearances.

If worst comes to worst you can get another engine, often given away free, see the "Free to a good home" section. But that is only a last resort.
 
I had a similar problem (documented on another thread). There were various other problems with the car but a lack of power was a major feature when I picked her up. Pulling out into traffic was a life-and-death thing and any incline would sap your speed, we won’t mention the fuel economy… First thoughts after compression testing (if memory serves I was getting about 50lbs on #1) was VSR so a new head was ordered. Turned out to be a split exhaust valve. Yes, the shims were a 'mare but I don't have the patience for those kinds of jobs...
JR Wadhams did sterling work getting bits to me quickly, the valve was about £20 and after fitting the car was performing like it should.

Another good point is I now have a cylinder head sitting in my shed…
 
Actually, come to think of it, I've got a 2.2TC head sat in the garage, if anybody wants any valves off it they're welcome to them, or the whole head if they want it, I think it is missing one valve.
 
4 cyl engines were burning out valves like that long before we lost leaded petrol. Hermione looks like it had a good head on it judging by those waterways, they're normally corroded out much bigger than that.
As for the compressions mentioned earlier they're ok for a running engine, and what does 0.25mm mean in real terms, tell them to get imperial tools if they want to work on P6's. I think it works out at 10 thou. which is at the upper limit for an inlet and a bit tight for an exhaust, but it won't make it run on 3 cyl and it wont compromise performance that much.
A burnt out valve as pictured will give near zero compression, and if used can lead to the seat falling out of the head, although the seats fall out without any help from the valves often enough.,
I'm sure they recommend getting rid of the car or another head because they're not competant enough to re shim the clearances.
 
Just to re-cap, we've got a 2000SC with poor power, the mechanic claims it's running on 3 cylinders and the compression readings are roughly within limits (10% variance, we've got 12-13%). The mechanic should have known to repeat the tests after pouring a teaspoon of oil in each cylinder, this can help to indicate if the problem is valve or ring related.
If it is running on 3, does it idle poorly ?, if so you can pull individual ignition leads off to work out which cylinder is giving the trouble.
If it's idleing fine but starting to missfire under heavy load, then the problem could be related to the ignition circuit, ie. a weak coil, condensor, dizzy cap, rotor, badly adjusted points, HT leads, and spark plugs (not in any order)
A weak spark will be fine at idle but will fail to ignite the mixture under load.

Anybody else got suggestions ?



Edited By webmaster on 1173805336
 
I've said it before and it's worth repeating, get someone to look at it who knows what they're looking at and listening to. There is no substitute for experience and anyone who's been working on P6's for any length of time should be able to tell you what the problem is without even laying a spanner on it.
If you want to do it yourself start from the beginning with the basics and work through in a systematic manner and you should come across the cause along the way. (Which is basically what Richard has just said.)
 
My hands are up,i really don't know what to do.

Idling speed is a bit up and down,sometimes to fast other times needs a rev to stop it cutting out.Bloke who looked at it is usually pretty keyed up and has a lot to do with Fiat x-19's but by his own admission the P6 is something he's not worked on before.

The mechanic at work who's helped me out with all me other bits is keen to have a crack at the valves and the like.

There's a place nearby in Shrewsbury,F.W.Thornton,that i was going to get some prices from and check J.R.Wadhams as well.

As for getting someone to look at it who knows P6's,does anyone know of anyone in my area?If anyone was willing to offer their time and have a listen I could come out,as long as there was no big hills!

Like i said i really don't know what to do and i'm not to proud to ask for help.

Thanks
 
Hermione - Ye Gods! Mine had a little wedge out of it, like a grinning Pac Man, nowhere near as bad as yours and still it caused chaos!

Harvey - Experience comes from poor judgement; good judgement comes from experience. It's a nasty ol' catch 22 innit?!

Borat – Telford's not too far from JRW's and I'm sure if you arrange a meeting they'd be able to help out. They may sound like Eeyore on the phone but they do know what they're doing there. Don't give up and don't fret; we've all held a spanner the wrong way up at some time in our lives and learning how to sort the buggers out yourself is rewarding and fun (if a little hard on the knuckles sometimes!).
 
JP6 said:
Harvey - Experience comes from poor judgement; good judgement comes from experience. It's a nasty ol' catch 22 innit?!
Click to expand...
True enough. The first P6 I ever worked on was such a pain because I didn't know what I was doing (and neither did anyone else where I was working) I swore I'd never touch another. Then I did a 4 year apprenticeship at a Rover dealer working on P6's virtually all the time, and had the benefit of the accumulated experience of others to help avoid the pitfalls. I then found they were easy enough if you know what you're doing, so spent the next 20 years working on nothing else, and while they're still going there will always be people who take them on without a clue what they're doing so care is needed to find garages of the old school with specific P6 experience to do your work.Which with the passing of time becomes progressively more difficult. No matter how long you do them there's always something new to learn, but starting from scratch now is more difficult (IMHO) because there just are not enough of them on the road doing the sorts of mileages (10 to 12K a year) to enable anyone to have P6's coming through the door day in day out for servicing and repair to gain the experience that you could have got 20 to 30 years ago.
 
I am new to P6s, but i am really surprised to see damaged valves like these. The P6s are supposed to be (and i believe it) quality engineered cars but this is a little dissapointing.
I pressume that such a damage is down to low quality of materials which is something that the company should put right from the beginning with not much hassle.

Do you know if this kind of damage occurs often to a reasonably driven 2000 or is it something happens only on thrashed engines?

By the way i was reading in contemporary road tests that the car (2000 TC) will cruise at 100 mph without strain as that speed the engine turns at "only" 5100 rpm (!!!) with the red line starting at 6000.

Yeah right, i thought, perhaps you won't have any rods coming out through the side plates, but dropping a valve or two?

Anyway, what i want to know is can a standard 2000 TC (assuming the engine is in good condition) withstand cruising with the engine turning around 4000 rpm or is it too fragile for this? I will not do this everyday, but i would like to enjoy the occasional weekend trip in my Rover.

Demetris
 
My owners manual for the 2000TC gives me recommended tire pressures "when driving cinsistently at speeds of over 105 mph"
Further it advises me not to do this unless I can obtain the proper octane.
So pump up the tire, fuel up, and go

Dick West
 
I've seen valve damage like that on all sorts of engines, old and modern, so I don't think its anything detrimental to the rover "quality image".
 
going back to borat's OP,...the symptoms he describes leads me to think that he has a valve/head gasket problem, before i finally took the head off hermione i had compression pressures of 170,170,160,120,she would idle on 3, but ran ok on 4 (until i tried to pull my trailer), also the head gasket was rotting between cylinders 3 & 4, (30+ years old), i fitted the spare head/cam carrier/buckets/shims and everything was ok for a year or so,( i use hermione as my daily driver),then she started to misbehave again,....guess what!!..number 4 exhaust valve AGAIN, so rather than go through the hassle of finding SC exhaust valves again i converted her to TC (can't be many TC auto's about),that was over 2 years ago and she hasn't missed a beat since,...oh, and TC valves aren't compatable with the SC head
 
As an aside, alledgedly the TC head is safe on unleaded, I ran mine on plain unleaded for a number of years without a problem but that's just my experience.

Out of interest I was looking for head gaskets, Ultra Parts list full head sets for all P6's, Ultra Parts Website, not sure if you can buy direct from them, but Engine Stuff Website list most Ultra stuff and you can buy online, they don't list the P6 sets but might be worth a call.
 
Demitris

The chances are that a car of this age has had the valves replaced in the past so they may not even be Rover parts ( must admit I've seen split valves before but not like that ! )

Years ago decoking an engine was a frequent activity - it is only in the last 20 years that detergent in petrol has made this a thing of the past - replacing valves was also more frequent.

As for Engine revs and speed, all cars used to follow the same rule before 5th gears came along ( unless you had a decent car with o/d )

1500 rpm = 30mph
3000 rpm = 60mph
3500 rpm = 70 and so on

So 4000 rpm or 80mph would be within normal expectations for your car - my attitude is, thats what it is meant to do so I'll do it, if it breaks I'll fix it - see no point in sitting there doing 50mph on the motorway - its anoying and dangerous to other motorists
 
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