new noise after V8 cam install

**pibby** · 13th February 2012, 04:35 PM

went down the bush block over the weekend.

ended up pulling lower intake manifold off and valley gasket and rocker assemblies and pushrods and lifters.

with regards to mike's comment – the play was in the lifters. There ended up being 9 which could be ‘pushed in’. the caps in the rocker arms were ok. I remember the mechanic at the time checked them out.

The lobes on the camshaft, I just don’t have the know how to work out if they are ok or not. I’m guessing they are (2 look more worn than the rest), they have only started wearing on one edge of the cam lobe. I guess this is to ensure the lifters rotate and is ok. Refer to photo.

There is one lifter whose base looks positively not right. Refer to photo. The rest have a normal pattern from all the photos I have seen online.

I remember when I first picked car up off mechanic there was a slight puff of smoke on startup. This has deteriorated on the way home and there is a straightforward answer. It looks like the valve stems seals have failed. On one head, of the eight valves I can clearly see 6 have failed. Refer photo. Anyone seen this before or more importantly what would cause it??

So in the end I have ordered a set of new lifters from karcraft which should be here this week. They were very helpful. I actually ordered 18, incase I got a couple of bum ones! Very surprised with price - $128 for 16 and these are from the oem.

As for valve stem seals. Rang workshop who put the heads/camshaft on. Left message, no reply yet. Rang company where exchange heads came from, waiting for response from them. have sent them photos as proof. they were expecting me to take the heads off and send to them in Victoria – I said ah……no. I asked greg at karcraft and he said yes can replace valve stem seals in situ. Get a spring compressor from repco etc (which I don’t have) and either put compressed air into spark plug hole or have cylinder down from top of its stroke then put some ‘rope’ in combustion chamber and wind up to top of stroke to stop valves falling. I might just end up doing this, this stuff looks pretty straightforward. But would like to know why the have failed.

Spark plugs looked oily.

so shall put lifters in when they turn up. Fingers crossed.

If this fails shall look into PLR’s idea on air in the oil (which I shall have to ask how to check).

Or any other possible cause……maybe the fifth moon on venus has changed colour???

**PhilipA** · 13th February 2012, 06:09 PM

Wow, It looks to me you are up for another cam,as well as the lifters.

I haven't seen stem seals as bad as that and it looks to me like the lift of the cam has been too high and hammered the seals. Obviously the collets/keepers are not supposed to hit the seals.

Without my going back and rereading the thread, is the cam supposed to be stock? or some aftermarket with high lift?

If stock then IMHO the most logical explanation is the preload is WAAAAAY too much, and this has also broken the springs in the lifters.

Some part of the valve train is wrong. Either the heads have been skimmed far too much, the cam has a higher lift than the distance to the stem seals, the preload is far too much, or even the lifters are too long.
In any case if you have a stock cam, you should be able to shim the rockers to reduce preload.

Regards Philip A

**bee utey** · 13th February 2012, 09:23 PM

It's also possible that your engine has had generic valve stem seals fitted. Datsun 1600 valve stem seals are very similar looking but taller. When I was heavily into P76's I had a tool to cut down the guides to fit the Datsun seals as they are adequate quality. Nowadays you just get the correct (blue) new ones for the LR engine and they are quite a bit shorter.

**PLR** · 13th February 2012, 10:14 PM

G`day Brett ,

between your thumb and third finger there appears to be marks that go right to the edge of the lifter base ?

If you have a metal rule or square etc , put across the lifter base surface and hold to a light , should be touch in the middle and space on either edge , convex , rule rocks .

May be the pics but the lifters appear not to run central to the lobes ?

Valve stem seals could be poor fitting . The seals should be a little better than 10mm in height .

There are pads on the heads to measure thickness if you can locate them , there are 2 tall on one side and 2 short on the other ,....

The tall for a std new head are 62.56mm and the short are 22.94mm .

The valve installed height is 47.63mm , it`s the distance between the end of the valve stem and the surface the spring base rests on .

The heads should have HRC 2479 on them or a higher number but not HRC 2210 .

Suggestion , if the cam is Wade send them pics of all the lobes and pics of all the lifter bases and ask there opinion .

Did you actually see the first cam out of the engine , the one this one replaced ?

**pibby** · 14th February 2012, 06:30 AM

here's some more photos of the cam lobes. i assumed they ran off centre to spin the lifters. maybe not.

peter - thanks for the dimensions. shall measure them up when next there. lots of food for thought. if the lobes are running off centre an area to look to find out why? shall check lifter bases - aside from the one in photo they all have the circular motion on them though some still do have lite scratch marks emanating from the centre out. will attach some photos. yes, i have the old cam which the current one replaced. good idea about contacting wade camshafts.

geez - not another bloody camshaft to go in.

philip - it is a wade cam. don't have specs on me but is definitely not a high lift cam.

bee utey - hope it is as simple as that.

shall keep digging.

**pibby** · 14th February 2012, 06:34 AM

some photos of other lifters that came out.

**PhilipA** · 14th February 2012, 08:29 AM

here's some more photos of the cam lobes. i assumed they ran off centre to spin the lifters. maybe not.

peter - thanks for the dimensions. shall measure them up when next there. lots of food for thought. if the lobes are running off centre an area to look to find out why? shall check lifter bases - aside from the one in photo they all have the circular motion on them though some still do have lite scratch marks emanating from the centre out. will attach some photos. yes, i have the old cam which the current one replaced. good idea about contacting wade camshafts.

Just about every flat lifter engine ever built has the lifters off centre to the cam to spin them.

The lifters should be CONVEX and if they are convcave as yours appear to be they are stuffed,

Despite all the details , IMHO the only fix is to start again and fit a new cam, lifters and it looks like stem seals , although they are only necessary on the inlets. Even if they are the wrong seals IMHO it is unlikely that the standard cam lift would cause interference.

Seeing it is a Wade cam , I would be asking questions and measuring the Base Circle Diameter Vs an OEM cam.( ie the radius of the lobe at the back compared to the cam centreline) This could be the cause of too much preload etc.
BUT really the only way to fix it is to measure everything when reassembling.
Just to make you feel better, this looks almost exactly what happpened with mine although I had a a supposedly standard 3.9 cam and my seals were not involved. When I put the SECOND new cam in, I bought OEM quality cam and lifters and measured the preload, which was still too much and I shimmed the pedestals.
I measured all the clearances and I still cannot work out WHY the preloads were too much as my heads were not shaved, my head gasket is exactly the same thickness as OEM.

All I can speculate is that standards for lifter depth or camshaft Base Circle Diameter have drifted over time, as I was assured and paid extra for what was described as "Land Rover OEM manufacturer but in a plain box"

Regards Philip A

mike 90 RR · 14th February 2012, 10:40 AM

Originally Posted by PhilipA

IMHO the only fix is to start again and fit a new cam,

I agree ... this lobe looks fairly distorted?? in shape (flat) .... and looks as tho the lifter is following the edge of the cam

**PLR** · 14th February 2012, 10:09 PM

[QUOTE=pibby;1627852]here's some more photos of the cam lobes. i assumed they ran off centre to spin the lifters. maybe not.

peter - thanks for the dimensions. shall measure them up when next there. lots of food for thought. if the lobes are running off centre an area to look to find out why? shall check lifter bases - aside from the one in photo they all have the circular motion on them though some still do have lite scratch marks emanating from the centre out. will attach some photos. yes, i have the old cam which the current one replaced. good idea about contacting wade camshafts.

Sorry Brett , i went about it the wrong way .

The reason for the centre running question was that i can`t from the first pic work out how close to running centre to centre things are but that is how it appeared .

I can see i should have just asked but it seemed the best way to understand the pic better .
You and PhilipA are right they don`t run center to center when in good condition .

If they are anything like center to center and looking at the lifter bases in your extra pics then the new lifters you`ve ordered would be wasted .

The way it should be is that the lifter centre line is offset to the low side of the lobe center line , again i can`t really tell from the extra pics but after looking more they seem to show the lifters running very low on the lobes .

It also seems from the extra pics that the cam may be sicker than the first pic suggested but i think the people at WADE could decipher the pics better and tell them of the lifters that won`t hold pressure as well as the rest of the story . They may like pics of the other cam also . They could also test the current lifters .

I`d suggest that because it seems to have happened twice that it`s more important to find the cause before any new bits are fitted .

Suggest when you see it again you make sure the lifter rotate ETC freely in their bores .

**pibby** · 20th February 2012, 02:49 PM

Went and did some measuring over the weekend.

measured the lift at camshaft by measuring the change in height of the lifter. This was on the top of the sides of the lifter, not down where the pushrod slots in. they were all good except for the exhaust on no 8 cylinder. I was getting approx 260-265 lift at cam which give or take 5 thou on my measurements (as it wasn’t exactly scientific) is close to the wade spec of 267/268.

Lift at cam should have been 267 but on no 8 it was reading approx 230.

checked preload and it was between 40-50 thou so ok.

Checked shims and both sides had 50 thou in.

Checked all valve stem seals – ALL are shot.

Lifters could rotate in their bores. I remember seeing this myself when the cam was being shimmed and would rotate when motor was turned on the starter.

The guy who put the camshaft in initially started the motor without any shims in ie did not check lifter preload even though I mentioned it a number of times. Wasn’t trying to be smart to him but if that’s what people who rebuild these engines do then I would like it done on mine.

So with no shims in lift at cam becomes 267+50=317
Lift at valve becomes 1.6*317=507

That looks high compared to all of the cam specs I have seen.
So I would guess that’s why all seals are shot.

Can the valve stem seals be replaced in situ? I read a post on here somewhere that the one(s) closest to driver can’t be. So this would mean taking the heads off to do?

PLR – I tried the measurements you gave me. Unfortunately it appears the valve spring sits in a recess so the measurements I was getting weren’t accurate.
Also had a look for the pads to measure head thickness, kind of thought there was one on the tyre side of the heads right on the corner??? I didn’t have much luck there.

I turned the motor over to see oil flow but I guess the pump has lost its prime. Tried taking the oil filter off but couldn’t budge it. had no tools so that will be next job when there.

So here is what I am thinking of doing :

Put new lifters in. they were only$120-130 and are OEM.
Adjust for correct preload.
Ensure oil is primed before start engine.
Have a go and see if get lifter noise or not and see how it drives.

Not being lazy but thought this would be a good exercise to determine if the problem lies elsewhere or is to do with the problems I came across since having a look

Ie a rocker arm bolt being finger tight
Numerous exhaust manifold bolts being loose
Numerous lifters appearing to not hold pressure (is this because of being run with too much preload when first started without shims?)

I know it will need a new cam (I’m thinking the lesser of two evils is to have the cam lobe worn on an exhaust valve rather than intake?)

So whilst I’ve now had two wade cams I’ve had a look at the ERR5250 which came out on the 4.6litres. it is considerably different to the 3.9 cams and the wade cams I have tried. It has a LSA of 115 whereas all others are 109 or 110. duration of 267/264 whilst all other rover were 285. the valve opening/closing times are quite different to the other rover cams too. It has a valve lift of .416 compared to the .390 on the 3.9 and 4.0.

Because of the longer stroke on the 4.6 (which my motor has with the 9.23 whatever compression and running lpg) does it make more sense to go with a custom grind using the 4.6 cam specs? Or is there another reason for ERR5250 to be different to the other rover cams? If I’m up for a camshaft then may as well start thinking about which cam to use………..again.

sigh.

Thread: new noise after V8 cam install

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