If its just emissions thats the problem Id say the first place to start would be the carbs etc, low compression is a possibility but if they are the only symptoms then not a very likely one IMHO.
I've just done a compression test on my R1 engine and the results are not too good.
1 - 110 psi
2 - 98 psi
3 - 129 psi
4 - 103 psi
each of these readings goes up by 1 psi after a few drops of oil have been dripped in through the spark plug hole.
Mr. Haynes suggests that the minimum pressure should be 192 psi with 206 psi nominal and 213 max, and with no more than 14.5 between max and min.
my lowest cylinder is half of the nominal and there is 26 psi max difference.
I did the test with the engine warm rather than really hot. Would this make much difference?
What could be wrong other than valve seating and head gasket? How do I check and how do I fix it?
[Edited on 12-11-2005 by smart51]
The first thing I would ask is do you know that your gauge works properly? Also what problems do oyu have with the enigne that made you do a
compression test?
Could you test the gauge on another engine which you know is OK?
Did you carry out the test with all the sparkplugs removed?
This'll allow the engine to crank over at a greater speed due to the lack of resistance and hence the readings will be higher.
Andy.
I didn't have all the spark plugs removed. I'll try that tomorrow. More importantly, I didn't have the throttle open, it was just at
idle!
The reason I was testing the compression was that I failed my SVA on Thursday on emissions, specifically HC too high but CO OK. It idles quite
roughly. someone suggested that it might be misfiring or not burning all the fuel and that I should test the compression. So I did. I'll do it
properly tomorrow.
You say you were doing it "at idle"? Just checking but I assume you mean the throttles were at their closed idle position, and you werent
actually running the engine whilst doing the test?
If its just emissions thats the problem Id say the first place to start would be the carbs etc, low compression is a possibility but if they are the
only symptoms then not a very likely one IMHO.
No, the engine wasn't running
the throttle was closed to its idle position.
It was suggested to me that poor idling and high exhaust hydrocarbons could be a symptom of something more serious and that a compression test would
help assess the general health of the enigne.
I have previously stripped the float chambers and vaccuum chambers and cleaned them out with carb cleaner. I also removed the idle mixture screws and
cleaned them out with carb cleaner. Not knowing much about carbs, what else should I have done / should I now do?
Did you lean off all the primary jets?
Repeated the compression test this morning with the throttle wide open and all the spark plugs removed. These are the results in psi without / with
oil dripped into the cylinder.
1) 155 - 155
2) 95 - 99
3) 151 - 156
4) 153 - 155
the manual states 192 psi min, 206 nominal and 213 max. 155 is 75% or nominal, 95 is just rubish.
What can the problem be?
[Edited on 13-11-2005 by smart51]
Sounds a bit ominous, but again are you sure the gauge is OK, and its sealing well when screwing into the plug holes?
Does the engine look like its been taken apart at any point?
Well you definately have one cylinder dodgy, but it may be the only one?
Source of the motor?
How old?
How many miles?
Crashed?
Likely to be needing valve seats, but could be a dodgy bore...
Remember, bike engines are far more prone to thrashing and wear than a car engine of equivalent miles...
If its done 20-25,000 miles its VERY likely to want a rebuild...
I did the test a couple of times on each cylinder so I would expect the results to differ if wasn't sealing correctly.
I don't know the milage of the engine or how it came to be for sale.
its worth checking the things that arnt gonna cost any money first and 20,000 miles is nothing for a road going r1,most the times they dont even need the shims doing on the big service,but if its been track dayed lots of times and had plenty of animal abuse then the valves do stretch a little which closes the gap up on the shim which then leaves the valves open.it might be worth taking off the cam cover and giving them a quick check. r1 engines are designed to burn oil to save on wear ,but if there run low then the poo hits the fan...but if youv checked everything then like g man says a strip down could be on the cards
Yep,
Agree with Ox.
Gotta be worth checking the valve clearances first.
Usually, a compression test is carried out to compare readings between cylinders - not necessarily to compare to a reading given in a manual etc.
So it does look like you've got one definite dodgy cylinder as the rest are comparable with each other.
Did you retry the test after drizzling a little oil down the bores?
If there was no significant increase in the readings then it would suggest a problem with the valves not seating properly.
However, if you suspect a head gasket problem, then dependent on where it has blown, there are several symptons you can look for.
Check for emulsifying of the oil (looks like white goo) - caused when water gets mixed with the oil.
Is there any significant white smoke (water vapour) or blue smoke coming out the exhaust when engine is hot?
You could also carry out a 'sniffer test' on the coolant system to check that exhaust gasses are not getting in the waterways.
HTH,
Andy.
cooling system will presurise up alot more than normal if gasket is leaking to a water way or heavy breathing if leaking to oil way or oil in water or
water in oil. Or it could be blowing between to cylinders so presure is leaking to no 1 or three.
Check valve clearances first thou!
[Edited on 13-11-05 by zzrpowerd-locost]
Where did the engine come from? Some countries only get de-tuned versions - Switzerland and (maybe) Germany.
I took the cam cover off to look at the inside. I haven't got any feeler gauges I'll get some tomorrow lunchtime. I can get a piece of
paper between the cams and the exhaust valves but not between the cams and the inlet valves. Doy you have to get the shims from a yamaha dealer?
That'll be another week's delay then.
The oil round the cams is still the red colour it was when it was put in. The oil round the clutch is the same. That's not to say that there
isn't "mayonaise" in the sump or elsewhere.
I don't know where the engine originated. it came from Edinburgh. Is there anywhere on it where it says 4XV1 or 4XV7 so that you can tell?
If you have to reshim the valves, then I'd have thought any Yamaha dealer should have them in stock and you do it on an exchange basis (at least,
that's how it used to work twenty-odd years ago at my local Kwacker dealership when I had to reshim the valves on my ol' Z650!)
You'll probably find, however, that you'll be able to swap a few of them between cylinders before having to go to the dealers.
Andy.
I would hope that they'd have a stock of shims but I wouldn't count on it. From experience, they stock NOTHING other than aftermarket
indicators and exhaust cans.
It looks like I'll have to reshim. Has anyone done this before? Any tips? I've read through the haynes manual and it looks tricky.
its hard to think of tips becouse when i used to do it everythings just second nature but one that comes to mind is mark the chain and cam gear(and
crank gear if there's room to get to it) with something thats not gonna rub off easily becouse the original lines on the cam gears wont meet up
with the cylinder head untill there bolted back in place ,,but if you do this make sure that when you put it back together that the chain hasnt spun
on the crank,,it just helps when you come to putting the cams back in to get them lined up ,,,some engines you can just do one cam at a time and then
we just zipper clipped the chain to the cam gear and rolled it out.
but apart from that ,check ,check and check again and everything will be cool
Excessive valve clearence shouldn't cause low compression...
Worth checking but I HIGHLY doubt thats the problem...
Excess valve clearance wouldn't cause low compression but not enough valve clearance might. I tried it with a sheet of paper yesterday and the
gaps are small to non-existant. I have bought a set of feeler gauges today and will measure the clearance this evening.
If the valve clearance is too small then when the engine is hot and the clearance shrinks, the valves may not be closing fully, causing a slight
leak.
I hope that's what it is cause I don't want to remove the cylinder head if I can help it.
excessive valve clearence wont cause low compression but if the gap is to big where the shim is on top of the bucket they can flick out,you havent got
that problem becouse your shim is under the bucket,,i think..if you do need to change the shims smart ,go for the bigger gap with in tolerance ,it may
have a slight rattle but it will run sweeter
I've checked my clearances with my shiny new set of feeler gauges. Some of them are a bit low but which ones should I replace?
My gauges are in these sizes
0.076mm
0.102mm
0.127mm
0.152mm
0.178mm
0.203mm
0.229mm
0.254mm
the limits are 0.110 to 0.200 for the inlet valves
and 0.210 to 0.300 for the exhaust.
most of my inlet valve clearances are bigger than 0.102 but smaller than 0.127 so may or may not be in tollerance. A few are between 0.076 and 0.102
and so are definatly too small and one is between 0.152 and 0.178 and so is just right. I noted down which valves easily took the 0.102 shim and
which were a bit tighter.
most of my exhaust valves would easily take the 0.203 gauge but not the 0.229 and so may be in spec and a couple are between 0.229 and 0.254 and so
are just right.
Repacement shims come in 0.050mm intervals and so may shift the slightly too small towards slightly too large.
For those who have followed this thread, the no.2 cylinder has the worst clearances with 2 of the 3 inlet valve clearances being out of spec.
So the dilemma, which should I replace and which should I leave?
Also, could this, or the low compression, affect the high hydrocarbons in the emissions test?
[Edited on 14-11-2005 by smart51]
when you push the guages in they should have a little drag to them.
seeing as your going to have to take the cams out anyway i would go down a shim size on all the ones that are between .102 and .127 .
the exhaust shims depends on how slack the .203 felt,other wise go down on all the exhaust shims that wont take the .229 .your better nearer the max
limit than the smaller limit,,you will probably be able to use some of the old shims that you take out anyway so just play it by ear but realy you
could do with the inbetween feeler gauge's just to see how tight all the gaps realy are..if the ones that wont take a .127 or the .229 but will
take a .120 or a .220 then its up to you but remember the gaps will only get smaller as the valves stretch in time but after saying all that if
the cams didnt have to come out to change the tight ones then i wouldnt replace any of the ones that are with in tolerance not matter how close to the
smaller limit they were
[Edited on 14/11/05 by OX]
I replaced the shims yesterday and it wasn't such a bad job, until I dropped on into the oil in the cylinder head. I tried to get it out with
long nosed pliers but it just slipped further and further out of reach.
It is now sat somewhere where it can't be seen down near the exhaust valve springs of cylinders 1 and 2. I've tried to hook it out with
wire but can't even feel it.
Will it do any damage if left? If so, How do I get it out?
magnet on a rod?
A magnet on a rod wouldn't be any good as the passage it has dropped into has a sharp 90° bend in it. A magnet on a wire on the other hand...
Where can I buy a small magnet? I have never bought a magnet before.
Try one of these
quote:
This is not a magnet for the inexperienced. These can break fingers if a mistake is made. This is absolutely the strongest, most dangerous product we carry
The magnet doesn't need to be strong, just strong enough to lift the lost part, not the entire engine!
You could try a speedo pickup magnet the ones I got from ETB for a mates car were very strong for their size and only a couple of a quid or so incl
postage.
If you suspect the head or cams I have a spare complete 00/01 head which is in good nick which I havent thrown to the ebay hounds yet.
I bought some from an ebay shop earlier this year, they were cheap enough and arrived quickly. You could buy a pickup tool and take the end off.
quote:
Originally posted by smart51
Excess valve clearance wouldn't cause low compression but not enough valve clearance might. I tried it with a sheet of paper yesterday and the gaps are small to non-existant. I have bought a set of feeler gauges today and will measure the clearance this evening.
If the valve clearance is too small then when the engine is hot and the clearance shrinks, the valves may not be closing fully, causing a slight leak.
I hope that's what it is cause I don't want to remove the cylinder head if I can help it.
quote:
Originally posted by smart51
I didn't have all the spark plugs removed. I'll try that tomorrow. More importantly, I didn't have the throttle open, it was just at idle!
The reason I was testing the compression was that I failed my SVA on Thursday on emissions, specifically HC too high but CO OK. It idles quite roughly. someone suggested that it might be misfiring or not burning all the fuel and that I should test the compression. So I did. I'll do it properly tomorrow.
if i was in your pos i would totaly dismantle the engine.
Its the only way that you can be sure and trust on your engine.
its now the compression what low, who says that if you rebuild its solved?
and after that maybe the gearbox says goodbye?
wy not do the complete service?
make an list of the status of every bad part get the prices and see if its worth it?
offcourse you cant let that piece over there what if it touches the spring?
it will damage the spring..and then you loose the valve and then you have REAL engine damage...
Take of the head and look at the valve sittings? i think that your engine has been running lean.. and then the valve's get hot and they start to
wear...
and then you loose compression..
i would take an complete look at the pistons and rings etc. wy?
what if your valves are damaged you repair then you do compress and you an slight improved than you can dismantle it again...
just buy the hayness or go to work and take the engine to a specialist..
if the engine isn't reliable the hole car isnt'
just my 2 euro cents
Tks
OK. A magnet on a wire got the shim. PLaced the shim into its valve and refitted the cams and chain. Turned the engine through 2 revs by hand and
checked the cam positions. All OK. Checked the clearances again. 7 are better, 6 are worse. 5 of the valves were not touched at all and yet 4 of
them have worse clearance than before. How can this be? All the shims that I replaced are smaller than they were so the clearances should go up,
no? They all seated nicely and the buckets slid in smoothly. I even made sure that the buckets were only taken off 1 by 1 so that they went back in
the same place. Even the bolts for the cam holders went back in the same place.
I turned the engine over on the starter motor a few times to see if this migh seat them all a bit. It had no effect.
quote:
Originally posted by stevebubs
Another, simpler, cause of a high HC level is an exhaust joint not sealed properly....
[Edited on 16/11/05 by stevebubs]
I've just spoken to a repair shop who guessed without looking at it that it might cost around £120 labour plus parts to recondition my cylinder
head if I take the head in to them. Is this about the right kind of price?
How much would a bare 1998/99 R1 engine cost me if I were to simply replace it? I don't want to get into the game of replacing bit one by one
until I have a new engine.
The price sounds OK but you'd need to check what parts were likely to be needed otherwise it could get expensive. A bare engine is still going to
cost you £7-800 minimum Id think, but you could offset that by selling all the bits from your current engine, I did that with my knackered blade
engines and salvaged several hundred quid from them.
Why not just buy Jim's head off him though, Im sure it will be cheaper?
Is the 00/01 head the same as/interchangable with the 98/99? Doesn't the 00/01 have the Air Induction System pipe work and things? I suppose it might be a simpler option.
Im not certain they are the same so get confirmation first, but Im fairly sure. The AIS is only 4 pipes coming out just below the exhaust ports, they are easily blocked up and wouldnt affect the running on your ECU etc.
Bucket and shim valve-gear tends to suffer more from valve recession and stretch, as opposed to wear. Hence the reason why your clearances have closed
up!
I would be re-shimming your valves to the top-side of the tolerance and try your compression test again, maybe then inserting a bit more oil than you
were doing into the bores as R1s tend to be built quite loosely. If you don't see any change after inserting the oil, maybe your valves are
passing then. £120 to have your valves lapped back in isn't too bad, although it's something you can do yourself whilst sitting in front of
the telly on an eve! At least then you'll know that it's been done right, and yes, you may get another head for less than that, but
who's to say it isn't in any better condition than yours unless you drop the valves out???
If you do decide to lap them in yourself, don't buy valve grinding paste from a motor factors as it's pants - go to a proper old-skool tool
place and buy some medium and fine Carborundum paste as it's a lot better quality.....
for the sack of another hour i'd deffo try reshimming it again,you might of done something wrong the first time,,whats it cost you so far,,maybe £20 and a bit of time
So why would the clearance on some of the valves go down if smaller shims were used? especially on valves where the shims and buckets were not removed?
When you measure the clearance on each valve, is the cam positioned right in the centre of the heel? (i.e. minimum lift?)
If not, your results won't be truly repeated. Or if you removed the cams, are they in the right way round and torqued down correctly? All of
these can make a massive difference....
I would reshim the valves again as mentioned, then check, check again and check again as your time is free!
maybe you checked them wrong or put it together wrong or put the wrong size shim in,,theres no other way it can do it....unless the valve heads are about to drop off
sounds like you had the cams on part lift...
There is a specific engine position for half the cylinders and another position for the rest...
If you dont use those positions then you will have inaccuracies...
Make sure you micrometer the shims, and not vernier them...
I measured the clearances as described in the Haynes manual. With the engine cold, rotate the crank until the inlet and exhaust lobes point away from
each other by an equal amount. This is at TDC on the compression stroke. There is even a marker on the cam and cam cover so that you can align them
for cylinder 1. The cams are in right (on a 5 valve cylinder it's hard to get them wrong). They are fully tightened up. I measured the
clearances using a new set of feeler gauges and I did it twice on each valve to make sure.
The shims are numbered according to their size. Perhaps they are worn. Perhaps they are not seated correctly. I lifted all the shims again one by
one after I'd swapped them to make sure the correct number shim was fitted.
Finally I understand why so many people advertise their kit for sale when 99% complete.
and your sure you havnt got the cam sprocket one or more teeth out,,i just cant see the gaps changing unless you have
[Edited on 17/11/05 by OX]
I've just done a compression tests and the results are a bit better than before. All the cylinders are now in the range 145 to 155 psi with the
best one beng the cylinder that was worst.
The cams were 1 tooth out when I first put the chain back on. I saw this after turning the crank through 2 revs. The error crept in when tightening
the chain tensioner. I fixed this before measuring the clearances.
is 150 psi too low when the book says 206? I've had some people say yes and others no.
if there roughly all the same i wouldnt worry about it .
try the car see how it feels .
i wouldnt waste any money stripping it down,you could strip it all down and find nothing,you could strip it all down find something and then something
else fails.
How do you know that your gauge is accurate? As someone said previously, the test you're doing is just looking for consistency between cylinders.
Mechanical pressure gauges are notorious for their inaccuracies, so I really wouldn't trust it.
As I said, the best way to measure the clearance is to make sure that the heel of the cam is towards the valve (i.e. the lobe pointing away from it).
Then, that will give you a true maximum clearance and also repeatability.
[Edited on 18/11/05 by Coose]
I replaced the last few shims that were under today and then had a thought. I seem to have over torqued the cam shaft holder bolts. After consulting
Haynes I found that they should only be 10Nm. It seems that it makes all the difference. all my clearances are now comfortably in the stated range.
I'll finish rebuilding the engine tomorrow and will then continue the search for a garage that will measurethe emissions and let me adjust them.
nice one dude,hope everything goes to plan
yeah,
just measure that all the cil are the same..
press. then in fact they are all good or all wrong.. in case the engine starts good when its cold and also when its hot, i think your engine is just
fine....
Tks
Thanks Tks. A bit of reassurance is nice. It does start very quickly which is a good thing. I took it out for a few laps of my local dual
carriageway today to burn off all the oil and generally bed the engine in a bit more. It does seem to pull a bit better now than it did.
I also revved it quite a bit to clear out any deposits that may be worsening the emissions. Even though the road in question is 1/2 mile from the
houses, my wife said she could still hear it.
I found a bit of frost on an island where the sun hadn't got to it Boy was the wind cold today.
[Edited on 19-11-2005 by smart51]