Valve Clearances after Timing Chain

[lewisnort]

I measured the valve clearances a while ago and determined that a few needed to change and swap around.
I decided while I was in there I would do a new chain and plastic rails as I don't know the history of the current ones.
I swapped the buckets and the chain/plastics all in one fell swoop, torqued it all down, but now when I recheck the valve clearances most of them are reading tight, if not tight by spec at least tighter than they were.

The workshop manual does mention checking clearances during the chain replacement but would this really affect it? Could it be as a I didn't originally do all the torque settings but trusted the way the engine was left that they were off?
Or have I destroyed it irreparably in some way...
The new chain is significantly tighter too, the adjuster piston is barely out of it's housing while the old one was out a fair amount, I just chalked this up to proof the old chain needed replacement.

[Laitch]

Replacing a timing chain is an exacting procedure. There's isn't a way for anybody to verify that it was done correctly in your case. A new chain on new rails is likely to be tighter than a worn chain on worn rails, if both have the same number of links.
What is certain is that if a valve clearance is set at specification—whether at one end of the spec, the other end of the spec or in between—the valve clearance has been set to specification. It is neither loose nor tight until its measurement is outside the boundaries of the specification.

I measured the valve clearances a while ago and determined that a few needed to change and swap around.
I decided while I was in there I would do a new chain and plastic rails as I don't know the history of the current ones.
I swapped the buckets and the chain/plastics all in one fell swoop, torqued it all down, but now when I recheck the valve clearances most of them are reading tight, if not tight by spec at least tighter than they were.

The workshop manual does mention checking clearances during the chain replacement but would this really affect it? Could it be as a I didn't originally do all the torque settings but trusted the way the engine was left that they were off?
Or have I destroyed it irreparably in some way...
The new chain is significantly tighter too, the adjuster piston is barely out of it's housing while the old one was out a fair amount, I just chalked this up to proof the old chain needed replacement.

The workshop manual does mention checking clearances during the chain replacement but would this really affect it? Could it be as a I didn't originally do all the torque settings but trusted the way the engine was left that they were off?

If you cannot trust what the manual indicates, discard it. As far as your trusting torque settings: which setting were you trusting and did not change—all the torque values of every fastener in the head that you did not loosen?

[lewisnort]

It is neither loose nor tight until its measurement is outside the boundaries of the specification

What I mean is for example the intakes reading previously 0.15mm go and 0.18mm no-go are now almost across the board 0.13 go 0.15 no-go.
Exhausts that were mostly 0.28mm to 0.30mm are now tighter than that.
They've not all become the same amount tighter either. Some more than others.

which setting were you trusting and did not change—all the torque values of every fastener in the head that you did not loosen?

All of them, but more specifically in this case I suppose the bearing caps and the cam gears. I've set them now to 9nm and 54 respectively. I haven't loosened head bolts or anything like that.

There is also some difficulty in turning the engine over, (only after the chain replacement) bearing in mind I do have the spark plugs in so I'm fighting compression some what.
But the crank seems more free than the cams, I'll hit a tight spot and the cams will almost jump once it's passed. The timing marks still line up after a few rotations.

[Laitch]

There is also some difficulty in turning the engine over, (only after the chain replacement) bearing in mind I do have the spark plugs in so I'm fighting compression some what.
But the crank seems more free than the cams, I'll hit a tight spot and the cams will almost jump once it's passed.

The "tight spots" are when a piston is passing through its compression stroke. That's should be expected when rotating a crankshaft by hand with the plugs installed.

Is what happened here first you set the valve clearances and after that you replaced the timing chain and its  associated components?

If you're confident you followed timing mark alignments and the timing chain installation procedure accurately by the book, you'll now need to get your valve clearances back into spec again—intake 0.15–0.20mm; exhaust 0.25–0.30mm—and hope for the best. Otherwise, you'll need to start from Square 1.

[lewisnort]

Is what happened here first you set the valve clearances and after that you replaced the timing chain and its  associated components?

That is exactly what happened.

If you're confident you followed timing mark alignments and the timing chain installation procedure accurately by the book, you'll now need to get your valve clearances back into spec again

Close enough I'm sure, zip ties on the cams instead of special tool.
Time to take out another mortgage to afford all the new cam buckets.

[Scott_]

OK, I've not read in any of the posts, however it would affect what you are doing....
Did you remove both cam shafts at the same time, or just 1 at a time.
Are you sure you put the correct cam bearing caps back on the same journal you removed them from, and at the same orientation....
Not trying to be a smart ass, just asking a basic fundamental question and not make assumptions.