For all you techie guys, What is going on here?
- Thread starter Fireblade
- Start date
Top dead center on the piston,
Inlet tappet movement,
Outlet tappet movement,
Crank angle at all the points
Surely Google shows you how to set and check Cam Timing ........
Ray
,
Inlet tappet movement,
Outlet tappet movement,
Crank angle at all the points
Surely Google shows you how to set and check Cam Timing ........
Ray
,
I've no idea what engine that is, but it looks like the cam is under the head. So maybe they have a dial indicator on each valve stem to measure lift at valve as there is adjustment in the rocker assembly, and the third is on the lifter itself to check the cam is dialed correctly. I've only ever played with OHC so that is a guess.
Just checking in to see who's awake! No - really, I am about to do a rebuild of an R5A engine, and my view with rebuilds and camshafts has been "to let sleeping dogs lie" - but then I've only done vanilla rebuilds of motors in generally sound condition - just cleaning up a head, swapping out pistons and sleeves, doing big end bearings and not even touching the crank. But I a fear I am about to venture into virgin territory and this photo freaked me out 'cause I don't have any of this kit available!!! Will be giving Mr Google a workout.
Hi Fireblade
If you are doing a rebuild back to standard specs and parts then none of that gear is needed. You do need a manual to know what to do but these are available, and the important things to check, measure or set are shown and the logical procedure to follow to only do it once. There are some tools needed and shown but most of these you might have already.
Fear not just get the information and study it first. I caution on using google and utube for information as I have seen lots of crap on there that I consider rubbish or even disinformation.
But I do know what is rubbish and what is good. A proper manual, paper or electronic is a great resource for a beginner to use and learn from.Jaahn
That guy is a little bit anal in measuring when the valves open and close in relation to crank position and piston position, that's all. You may or may not need to do that depending on how involved you get in your rebuild. If you mix and match parts you might need to do that, if you use OEM/standard parts you might not, but it's good to check things before hand so you don't have to go through a long list of things that may be wrong if after the rebuild the engine doesn't work as it should.
I had a constant miss at idle on my R17TS. Changed plugs, twinDCOE's, dizzy, fitted electronic points. But still a constant miss sound at idle. I had the cam reground to standard before the rebuild. So there was no reason for the miss that I could find. So made up my own degree wheel with a school protractor out of card board. Checked the top dead centre with a marked bronze welding rod. And just watched the valves or used my fingers to feel when the valves opened and closed etc. What I found was a difference in the cam grind. Normally should be 42-72-72-42. It was actually ground 42-72-72-52. Hence the exhaust stayed open longer causing the nice miss sound. Put it all back together and didn't worry about it any more. Why did the grind shop do that, who knows. But the lessson is that you don't need to spend money to do checks like that. It is'nt an F1 engine is it?
Brilliant Mr Sunroof... I presume it ran well at revs?
The really important equipment is the bricks, it would be terrible to set up all that abundance and it fell over. As long as it runs sweetly and pulls hard on the road, it will be fine. I have the sticky base indicators etc, slip gauges, micrometers but in the end it is knowledge and experience, or advice. I have seen bush mechanics dispense with most of the equipment but still set up an engine to run well and last under use... Do what you can with what you have got - that's the challenge IMHO!
Geez. What shop did that, so we can avoid it?
Thing is, to check the grind only you don't need to have the engine together. Just a protractor and some means to set a reference point.
I made myself a rather accurate angle measuring device by bolting two protractors together through the centre.
Sure runs fine once the right pedal is pressed.
These guys might check something but as far as I can see there is nothing they can do with what they find because that is a fixed key allocated cam gear that is what it is.
My degree wheel is very professional, I printed one from the net and then laminated it. It is perfect and accurate and has been working for many years setting up many cams.
Frans.
My degree wheel is very professional, I printed one from the net and then laminated it. It is perfect and accurate and has been working for many years setting up many cams.
Frans.
You don't even need to do that, that's the thing with the circle. They're all perfectly accurate by design. There's only 360 degrees around it, you can't get it wrong.
You can actually make a very accurate degree wheel by dividing a circle into 360 degrees (or even down to half degrees or quarter and so on, depending on your patience and how much time you want to spend on it) using only a divider and a straight edge (not even a ruler; in fact a piece of string is enough).
You can actually make a very accurate degree wheel by dividing a circle into 360 degrees (or even down to half degrees or quarter and so on, depending on your patience and how much time you want to spend on it) using only a divider and a straight edge (not even a ruler; in fact a piece of string is enough).
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Maybe you should have got the organ grinder to do the grind and not his monkey.I think I remember you mention something about that before. Silly organ grinders