Oil level rising - exhaust valves?

:D :D This evening went well. After I managed to get the the plug removed on the front of the cylinder head that covers the tensioner, managed to get a 1/8th hex key into the tensioner and remove the chain tension. After this, I was easily able to rotate the camshaft a little and get the camshaft locking pin in. I am going with the theory that the chains are a bit slack (thanks Chris), rather rhen the "wound" crankshaft theory which sounds horrible.

The car is showing 80,000 but when I got it the odometer was stuck. Going by the limited history/MOTs I have, it looks like it stuck maybe a couple of years ago. So, can only guess mileage is maybe 80-90k?? Certainly, the car in general is in very good condition and appears well maintained - haven't found anything nasty yet. I don't know when timing chains were last changed. Haynes manual suggests 30,000, so will maybe see if I can get a set - any suggestions on a good supplier appreciated :?:

Managed to remove camshaft chain wheel without dropping any bits/tools into engine - thanks for warning OrganDoctor. I am terrified of this, so have plugged up the top of the casing with copius amounts of blue roll.

Also, thanks Harvey for pointing out vernier adjustement :oops: . When removing top chin weel, I noticed that it was bit more complicated looking than expected - will check out the manual to see how to correctly set it up when (if :roll: ) I get it back together.

Need to pop y B&Q tomorrow on way home from work to get 3/8th inch nut to secure chain wheel to locking plate - all the nuts'n'bolts I have are metric. Although I collected a pile of imperial tools before starting with P6 ownership, I never thought to get a selection of nuts, washers etc.

Thanks again to everyone for help.
 
JVY said:
I don't know when timing chains were last changed. Haynes manual suggests 30,000, so will maybe see if I can get a set - any suggestions on a good supplier appreciated :?:
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wadhams do them with the tensioners too, good deal at £55. But check they come with split pins. Putting on a chain without one, if I remember correctly, requires the oil pump to be removed!!! The sprocket on it does not come all the way out so getting the chain on and off is a right pain in the backside. Which is why I guess the kits do tend to come with split pins. Some of the ones I've seen on eBay don't have them, I know I brought a couple when I rebuilt my engine, but the block was in bits so no big deal.
 
You shouldn't really use split links in the chains. I've done pairs of one piece chains, and I have fitted a bottom chain on its own using a split link but TBH I found it more of a PITA than doing it properly. (Mind you, I was doing the job laying in the gutter in the street, while it was absolutly p1551ng down!)
 
Richard/Harvey, thanks for advice on chains. Will definitely try to get a set on while the engine is half apart - better than chancing a failure. Thinking I will go for one-piece if I get a choice, despite the possible extra hassle. I may be deluding myself but one-piece just sounds stronger?

Got the fuel pump refurb kit (minus the neoprene seal I was warned about :roll: ). Anyway, reckon the old seal was OK as there were no traces of oil in the lower chamber when I removed it (just petrol). So, I fitted the new diagphram and the glass bowl sealing ring. The kit also came with new valves, However, I never fitted them as the old ones seemed to be working and there seemed to be no easy way of getting old ones out without risking damage. Put it all back together and sat it aside to get on with camshaft removal:-

I got some 16mm dia. steel tube (1mm thick) and cut a couple of trial spacers. Removed no.2 bearing cap and put head bolts back in with M12 plain washer top & bottom of tube. On trying to torque up to 55ft/lb, the tubes just started to crush :shock: :shock: Conclusion - 1mm stell tube useless. Tomorrow, go back to hardware store and get some M14 nuts to use instead - I should have listened to Demetris advice about using nuts in first place.
 
Yep, the nuts work fine. Used my set several times while getting the shim clearances right.Put them away for possible future use.
 
Aren't split link chains considered to be a bit of a bodge ? Once the little " U " shaped clip falls off you're in trouble
There is meant to be a way the clip should face for best results but I don't know what it is
 
DaveHerns said:
Aren't split link chains considered to be a bit of a bodge ? Once the little " U " shaped clip falls off you're in trouble
There is meant to be a way the clip should face for best results but I don't know what it is
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The closed end of the clip should be at the front, in other words as the chain rotates (in whichever direction it goes) the closed end gets there first.
 
It's the same principle with any split link chain,the closed loop of the horseshoe clip faces direction of travel,if not, the open end can snag on the chain guide and become detatched,
 
:D :D Got a couple of dozen M16 hex nuts today to use as spacers on head bolts while removing camshaft - x2 nuts in conjuction with an M12 plain washer did the trick and I got the camshaft off OK (thanks again Demetris/Harvey).

I only had time to remove one tappet and take a look at the shim. I was a little surprised to find that it's thickness was 0.415 inches. The Haynes manual lists the thickest shim as 0.352 inches. Only theory that I can come up with is that the exhaust valves (or maybe seats) were replaced at some stage with slightly shorter stemmed ones; hence the thicker than standard shims :?:

Anyway, I am now tempted to adjust the shims to set the right exhaust valve clearance and stick the camshaft back on. This is rather than removing the head and risk upsetting things best left alone. Before removing the camshaft, I measured the clearances (cold) at 6thou - Haynes book says they should be 13-15thou. Therefore, I need to shave something like 8thou off each shim. As one side of the shim looks flat, I am thinking that I could get a little piece of plate glass to use as flat/hard surface. With the glass and some fine valve grinding paste, I reckon it would be easy to carefully shave 8thou off each shim??

I suppose correct route would be to try and buy the correct shims. However, as it might be very difficult to get x4 of exactly correct thickness, the "grinding theory" sounds good. Has anyone tried this or would it be silly to try :?: :?: Apart from getting thickness correct, main worry is keeping the shim surface flat and square. Will probably try to find a little piece of hardened steel and have a practice run first. I am thinking, even if I muck it up, I could always ask local machine shop to make some of correct thickness. Does anyone know exactly what sort of metal they are made from :?: :?: Apart from "very hard" :LOL:
 
Yes I think most people end up having to 'modify' the shims if they can't find any spares. It's why I've been looking at the shims bikes use. Just had no time to go to a bike shop and look at their spare shims, need to befriend one of the mechanics. Most modern performance bike use shims, I expect because of the high revs involved.
 
Since i kept my old engine i had a few more spare shims to play with. However, it was inevitable that i should modify some at the correct size. Most of the times i used an oilstone, and... a lot of patience. With a lot of work i could reduce them at 1 or 2 thou that was necessary in my case. If you need to go down 8 thou i would say not to bother with anything like sanding. They are way too hard for this. Take them to a machine shop and it will be too easy.

Richard, if you find anything interesting on the bike front, let us know.
 
Early engines had one shim instead of two when new, so that's where the bigger shim has come from. For 8 thou change I'd calculate the two shims that you need to make the clearance.

I've got a fairly good stock of shims if you let me know what ones you need. (All available at very reasonable prices. :wink: )
 
I had some extra shims from another engine, but even with that selection I had to modify some shims to get the right readings. I used a piece of tubing to hold the shims flat while grinding material off.
I can't say it was a pretty job, but I got them close enough so I don't expect trouble. I am scrapping another 2000 So I think I will go after those shims to add to my collection.
 
JVY said:
I was a little surprised to find that it's thickness was 0.415 inches. The Haynes manual lists the thickest shim as 0.352 inches.
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If you have a .415" shim and want to increase the clearance by .008" I have a .407" one piece shim.
 
:D I think I am getting somewhere..... After trying to grind shims on some glass with grinding paste, I very quickly gave up. As some of the shims needed reducing by 10thou, this was going to take a while!!

Then I tried using various grinding stones and discs in my litle Dremel tool - taking care to hold face of shim flat against surface. However, nothing seemed to make much impression. :roll: those shims are made of hard stuff.

8) As I had a set of diamond grinding stones (kind used for sharpening wood chisels), I gave these a try and they worked a treat. The roughest diamond stone, would shave off about 1thou for about 100 laps. So, I have now sorted all 4 inlet shims (they only needed 1 or 2thou off) and 3 of the 4 exhaust shims (which needed between 3 and 10thou off). After reducing shims using rough, medium and fine stones, I finally rubbed them on a flat surface with some metal polish and managed to get a nice flat/square mirror like finish.

Thanks for the offer of some additional shims Harvey. However, won't be needing them this time.
 
I can't ever recall a 4 cyiner engine with hydraulic lifters. No technic reason why not, though. But bear in mind the P6 engine design was frozen around 1961! It's very advanced for that date.

Chris
 
chrisyork said:
I can't ever recall a 4 cylinder engine with hydraulic lifters.
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Do you mean a concept version of the P6 engine or 4 pots in general? Been loads of other engines with hydraulic lifters, the most obvious is the ford CVH engine. But yes the engine was very advanced, many high performance engines still use shims, most if not all bike engines made today do. There is also some stuff on the net suggesting new engine designs are going for shims now, way cheaper to build. Not sure how correct that is as I thought all modern engines now use hydraulic lifters, cheaper servicing costs for the fleet market.
 
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