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Something wrong with those cams or their lubrication to wear the tips like that. I also suspect that the removal of ZDDP from oils (because it poisons cats) has a lot to do with it - ZDDP is an "anti scuff" additive to help with sliding contacts like cams on buckets - is why I only use certain oils (with at least 1200ppm ZDDP) in the Stag. This was a major problem in yank big blocks - because of the sheer size and weight of the valves in those (2" dia inlets!), any cam more "radical" than stock (and they were pretty lazy as stock) needed huge on-seat valve spring pressures, so using modern oils simply resulted in wiped out lobes.

Coming back to yours tho' - there must have been a lubrication failure to wear the lobes and journals like that surely?
 

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Discussion Starter · #702 ·
Those were my thoughts too, Wilf. However, when spinning it over by hand with the cam covers off there was loads of oil coming up on the lobes.

I’m wondering if it’s ever been run short of oil at some point in the past.

Trying to figure out if there’s a way too ensure oil is flowing through the block up to the heads before putting the new heads on.

Am also wondering if there’s any way the LPG could have caused it as they do run a bit warmer on LPG. I must have a look and see if the pointy lobes are on the valves with worn seats actually.
 

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I'm wondering if the recessed valves closed up the clearance between the valve shim and the cam lobe, to the point the lobe is riding the shim and just wiping all the oil off as it's only splash? Doesn't explain the worn bearing surfaces though, that looks like oil starvation. Maybe it's a complex situation of multiple issues have affected them? And to comment on an earlier post, the RR uses different cams to Jaguar on this engine, for lower peak torque spread, I read somewhere.
 

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Discussion Starter · #704 ·
Just off the phone to Kent Cams.

He reckons grinding mine down in a non starter as you can't put shells in the bearings in the heads.

Again, he said that building mine up and grinding them down was a non starter.

To customer make them I'd be looking at around 600 quid per cam and a 12 week lead time. 4 cams would be £2,500 by the time they've been done and shipped.

So it looks like the only option really is Land Rover and sourcing that one from the US unfortunately.

David.
 
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Just off the phone to Kent Cams.

He reckons grinding mine down in a non starter as you can't put shells in the bearings in the heads.

Again, he said that building mine up and grinding them down was a non starter.

To customer make them I'd be looking at around 600 quid per cam and a 12 week lead time. 4 cams would be £2,500 by the time they've been done and shipped.

So it looks like the only option really is Land Rover and sourcing that one from the US unfortunately.

David.
or a breaker?
 

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Discussion Starter · #706 ·
I've looked at used ones on eBay and none of them appear to be in a condition I'd want to fit them into brand new heads. There's not many there either as people want to sell whole engines :(
 
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Discussion Starter · #708 ·
I called them last week as I follow their channel too. I wanted to know what sort of figure I was looking at to have the valve seats replaced with hardened ones on the new heads. Unfortunately they've still not rang back.

I've come to the conclusion now that due to the fact there aren't any bearings on the cams that are replaceable, due to the fact labour rates are expensive, and due to the fact we seem to live in a chuck away world then new cams are the only realistic option.

At least then I can repurpose my old ones :)

Property Wood Floor Lamp Material property
 

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I called them last week as I follow their channel too. I wanted to know what sort of figure I was looking at to have the valve seats replaced with hardened ones on the new heads. Unfortunately they've still not rang back.

I've come to the conclusion now that due to the fact there aren't any bearings on the cams that are replaceable, due to the fact labour rates are expensive, and due to the fact we seem to live in a chuck away world then new cams are the only realistic option.

At least then I can repurpose my old ones :)

View attachment 192322
There's someone out there that'd pay £600 for that.:D
 

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Discussion Starter · #710 ·
It’s certainly a weird one on this car…

The Camshaft bearings in the heads and the caps that you unbolt have nowhere near as much scoring on them as you’d expect given the state of the cam journals. In fact, the worst journal on the camshaft matches the head and the cap that shows as near as dammit no marks at all.

This is one of the worst camshaft journals:
Automotive tire Gear Motor vehicle Differential Automotive wheel system


This is the corresponding bearing in the head:
White Light Gas Auto part Nut


You can see a little scoring where the two halves of the bearings join but you can feel it with your finger nail at all. It’s bizarre.

There’s a plate above the sump so you’d not be able to see the crank so I don’t think I’d gain anything from putting an endoscope up there.

There were no funny noises (in fact with the Supercharger belt off this engine was beautifully quiet), and no swarf on the sump plug when I got it or just now after 12 months and you can’t buy a crankshaft from LR. I couldn’t have this one ground either as there’s no option to buy oversize bearings for it so I don’t think there’s much point in going any further to be honest.

It is what it is now. I’ll order 4 cams for it and if anything else goes wrong I’ll either break it for spares or figure out how to put a 5.0 into a 4.2 😁

David.
 

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Discussion Starter · #712 ·
A friend of mine whose been a mechanic for years and has a huge amount of experience of rebuilding engines wonders if mine has had new heads and old camshafts fitted to them at some point now he’s just seen those pictures.
 

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A friend of mine whose been a mechanic for years and has a huge amount of experience of rebuilding engines wonders if mine has had new heads and old camshafts fitted to them at some point now he’s just seen those pictures.
I was about to suggest that as the only viable solution to explain the wear.
 

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Discussion Starter · #714 ·
The last couple of days I’ve been wondering about taking the block out of the car, removing the sump to clean the strainer and fitting a new oil pump.

I really don’t need the extra work (or cost) at the moment so I’m kinda pleased to see a few people agreeing with a possible cause.

I think I’m going to fit the new cams whilst plastering everything with engine assembly lube and crank it over to check oil flow to the heads before fitting the valve covers back. Once it’s started it needs to sit at around 2500rpm for 15-20 minutes to bed the cams in.

Once that’s done I’ll add a tin of engine flush, run it for a bit longer, drop the oil and change the filter before refilling it again with a fresh LR filter.

Think that’s as far as I’m going to go at the moment.

David.
 

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I don't believe there's an oil supply issue to the head, if there was, looking at the cam bearing surface wear, the bearing surfaces in the head should be totally destroyed.
 
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Well you did say that it looked as though it had been stripped before at some point.

Are there any casting numbers ect on the block and head?
 

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Funny how the harder material wears before the softer.
Honda used to have variants of their XL250 motorcycle back in the 1980's that suffered from insufficient oil/oil starvation and the cams would end up with huge grooves in them and the alloy head would have corresponding 'highs' on them..

When I say huge, I mean up to 2mm..

I seem to recall that it was due to the oil pump design having insufficient flow/pressure.
 

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It's not unusual for a hard surface to wear against a softer surface. For example, hard particles get held by the soft surface and cause wear against the hard surface.
 
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Discussion Starter · #719 ·
Finally got the quote from the company in America with the obsolete camshaft in stock. They’re quoting me $200 to ship it to the UK! 😳

Tried FedEx and UPS and they’re quotes were similar. Decided that rather then mucking around and trying to get a cheaper courier I might as well let them have liability for it in case it gets damaged in transit.

Got 2 more places to try in the UK tomorrow and if all else fails, it’s $611USD for one camshaft, then another 800 quid to JLR for the 3 that are available in the UK.

Getting fed up with no progress at the moment...

Decided against fitting the 6% Supercharger pulley and have sent the entire snout and the 6% pulley back to Powerhouse to get the snout machined and the 10% pulley fitted.

David.
 

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Discussion Starter · #720 ·
Made a start on removing the LPG tonight.

All of the pipe work, reducers, flashlube, etc. are now removed from the front end.

Hood Automotive tire Motor vehicle Automotive lighting Bumper


I then went into the ECU box and started to remove the LPG ECU. It’s amazing the amount of wiring that goes with this!

Motor vehicle Automotive design Automotive tire Electrical wiring Computer hardware


I had to cut the wiring for the 8 injectors and remove them from the LPG loom.

Motor vehicle Electrical wiring Automotive design Cable Audio equipment


I then started the process of remaking the loom to the injectors. Unfortunately the cables aren’t quite long enough so I’m having to solder in a little piece of wire as an extension. It’s not difficult, just time consuming. There’s multiples of the same colour cables so having to make sure I’m joining the right ones referencing the wiring diagram and checking with the meter as I’m going.

Electrical wiring Cable Auto part Electrical supply Electronic device


Just need to be able to open the boot (difficult when the battery is removed) to be able to get to the tank end of the wiring now. I’d filled it with LPG a couple of days before it went into the shed too so it’s sitting with a FULL tank of LPG so lifting that bugger out will be fun!

David.
 
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