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Re: Hydraulic tappets

Posted: 27 Jul 2011
by Way2go
mat_the_cat wrote:I have in fact managed to take the rocker cover off
Old thoughts of push-rods still come to the fore? :wink:

Re: Hydraulic tappets

Posted: 27 Jul 2011
by mat_the_cat
:oops: I try to write cam cover, but I have always (and probably will always) thought of it as a rover cover. I guess that's because the first few vehicles I had either had an OHC and rockers, pushrods and rockers, or in the case of the Alfa, two overhead cams, rockers and pushrods!

What's so shit about the cam bearing caps Doc?

Re: Hydraulic tappets

Posted: 27 Jul 2011
by Philhod
I know of several engines with OHC and rockers, Even twin OHC and rockers.
But I've never seen an OHC engine with rockers and push rods....even an alfa???????????????

Enlighten me please :)

Perhaps you think of it as a ROVER cover because of you fetish for BL stuff. :lol: :lol:

Re: Hydraulic tappets

Posted: 27 Jul 2011
by mat_the_cat
It was the 12 valve version of the old (pre GM) V6. The inlet valves were operated directly by a camshaft on each bank, whereas the exhaust had a little horizontal pushrod and rocker to operate it, to get a better angle between the valves (hemispherical combustion chamber).

Image

Fetish for BL stuff? You're thinking of Father Ted, I only like the Rover V8 which pre-dates BL!

Re: Hydraulic tappets

Posted: 27 Jul 2011
by mat_the_cat
Oh and Phil, listen to this and then tell me honestly that you'd still prefer a diesel!

Re: Hydraulic tappets

Posted: 27 Jul 2011
by Philhod
:lol: :lol: All noise and no power. Totally inefficient, thirsty and reliant on an ignition system that deteriorates with age.
Nasty smelly poluting things :wink:

Never seen one of those. The Triumph system was similar but without the push rods. They just had a rocker to each pair of valves, running 16 valves from a single central camshaft.

It looked weak as fuck but was actually quite trouble free.

Re: Hydraulic tappets

Posted: 27 Jul 2011
by Father Ted
mat_the_cat wrote: Fetish for BL stuff? You're thinking of Father Ted
Ohhhhh Yeahhhhh!
A Series with rubber wellies. Yum Yum Yum.

Re: Hydraulic tappets

Posted: 27 Jul 2011
by mat_the_cat
Philhod wrote:Never seen one of those. The Triumph system was similar but without the push rods. They just had a rocker to each pair of valves, running 16 valves from a single central camshaft.
It would be interesting to try and fit a pair of those heads to the Stag V8, as I think it's based on the 8 valve variant of the 4 pot.

Re: Hydraulic tappets

Posted: 28 Jul 2011
by Philhod
[drool] [drool] 32 valve Stag :lol: :lol:

Didn't Fraud do one with the cam direct on the inlet and rockers across to the exh, at an angle?

Re: Hydraulic tappets

Posted: 28 Jul 2011
by mat_the_cat
Not sure about the Ford unit but they don't have the best reputation where valve gear is concerned... From the usual sound of the Kent engine it appears they designed the pushrods a couple of mm too short!

Sadly (as usual!) there is a fatal flaw in my 32 valve Stag plan - you would need a mirror image of one of the heads. Doh! :oops:

Re: Hydraulic tappets

Posted: 29 Jul 2011
by Philhod
:lol: Nothing for it will have to fit 2, 4 pot motors side by side driving a central gear to the g/box.
A bit like an Ariel square 4 :lol: :lol:

Re: Hydraulic tappets

Posted: 29 Jul 2011
by mat_the_cat
Fuck that, you might as well just have 2 engines! There's a rather nice Alfa 164 about with an extra engine in the boot, want!

http://www.youtube.com/watch?v=ciElgEpQNFU

Borrowed some tools today and locked the engine and pump. Front cam pulley is a taper fit and was a bugger to pull off, managed it in the end with a bit of a bang. Just need to lift out the cam, replace the tappets and reassemble. The mechanic showed me the official manual - to time the cam correctly apparently you fit the tool in the slot on the rear of the cam and slide a 0.2mm feeler under one side of it, then tighten the front pulley in that position.

Re: Hydraulic tappets

Posted: 30 Jul 2011
by Philhod
Yeah, that sounds err....sound enough.
Technically, if the taper is morse, around 2 degrees, it should lock in the position it goes on without a key of any kind.

It's the same taper you get on taper drive drills etc. 8)

Unless it has a removal slot, the way to remove is, put your puller on and bang some pressure on, then tap with soft hammer

Re: Hydraulic tappets

Posted: 30 Jul 2011
by mat_the_cat
Yeah, that's what I did. Only I couldn't find the third leg of my puller so had to make so with just 2 (180 degrees). Was worried about cracking the bugger as I've done that before on a similar sintered pulley. (Call me a ham fisted bastard if you must!)

Re: Hydraulic tappets

Posted: 30 Jul 2011
by Philhod
:) OK. You're a ham fisted bastard....................... :lol: :lol: :lol:

Never liked sintered stuff. It can't be as strong as cast or certainly drop forged.

:roll: Takes me back to Young's modulus and all that shit 8)

Re: Hydraulic tappets

Posted: 30 Jul 2011
by mat_the_cat
I kind of asked for that! With the benefit of hindsight I might drill and tap a couple of holes in the pulley, so that I can draw it off with a couple of set screws against the head. Access is impossible for a puller unless you take the header tank off, which is just adding an unnecessary job.

Re: Hydraulic tappets

Posted: 30 Jul 2011
by Philhod
Couple of wooden wedges behind works, if you have something to push off.

Just fitted a new water pump to Gregzee's Corsa (we towed him in losing water wednesday)
Haynes book of lies tried to confuse me again. Says remove this and that but theres a fucking great engine mount casting in the way so stuck the jack under the engine and took it off.
Had the pump off in no time even though it has 9 bolts holding it on.
Anyway he's back on the road again and no probs reported.

He says " how can a pump go, just like that" I says, cars are like women. You just pranged it so it's thrown a sulk the pump is it getting it's own back

Sadly, he thought I was joking...........................He'll learn :lol: :lol:

Re: Hydraulic tappets

Posted: 30 Jul 2011
by mat_the_cat
Philhod wrote:Haynes book of lies tried to confuse me again. Says remove this and that but theres a fucking great engine mount casting in the way
It was a big revelation for me :idea: when it finally sunk in that following a manual blindly (as I used to do) is often not the best way of doing something. If you look at a job and assess it from first principles, maybe looking at a manual for guidance you engage a lot more of your brain power, and it may be that the 'official' way is not the best for your particular way of working. Or it could be the manual is plain wrong!

Re: Hydraulic tappets

Posted: 30 Jul 2011
by Philhod
:) All true. I wouldn't start any job without looking it up first. TBH I have never found it wrong and quite often I can see why he has chosen a particular method, having novices in mind, but you cansave hours of work by sussing it first.

It comes in handy for torque settings too, with so much aly and plastic about these days, you can't be too careful. :wink: (or even sintered stuff) :roll:

Re: Hydraulic tappets

Posted: 30 Jul 2011
by mat_the_cat
The only time I've known a manual to be wrong was a Russek manual for a Mitsubishi engine - on changing the camshaft it instructed you to remove the bearing caps and lift out the cam, followed by removal of the rocker cover! :lol:

Van now sorted, I've not run it up to temperature yet but it started perfectly with very little smoke, pump timing sounded OK and tappets were quiet straight away. 8) Hmm, does that mean I've been sold a solid set by mistake? [pray] Let's hope I can make some improvement on the mpg now!