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Hey guys,

A question for who knows a lot about solids in our engines. Ill call the cam grinder this arvo also.

Im getting a decently loud lifter tick.
Its a B6 with solids and custom cams.

How much do you need to spend to get a decent set of feeler guages? I have a 10 dollar set that seems fine. But im doubting a bit.

Basically its been 25000km since the engine was built. And Ive got some silly clearance numbers.
Ill post below, the clearances, in thou inch. From front to back. The first number was the clearances at 10,000km second at 25,000.

Inlet

8-8
8-8
9-9
8-11
9-11
8-9
7-10
8-9

Exhaust

9-8
9-7
9-12
8-12
8-8
9-7
8-7
9-7

Different feeler guages than last check though. Hard to believe its lost clearance some places.

Cam manufacturer quotes specs of 8 for intake and 9 for exhaust.

Anyone have any ideas?

Dann

I see you there woz and mx52nv. Come on fellas, I know you both know LOL.

Dann

NitroDann wrote:Hey guys,

A question for who knows a lot about solids in our engines. Ill call the cam grinder this arvo also.

Im getting a decently loud lifter tick.
Its a B6 with solids and custom cams.

How much do you need to spend to get a decent set of feeler guages? I have a 10 dollar set that seems fine. But im doubting a bit.

Basically its been 25000km since the engine was built. And Ive got some silly clearance numbers.
Ill post below, the clearances, in thou inch. From front to back. The first number was the clearances at 10,000km second at 25,000.

Inlet

8-8
8-8
9-9
8-11
9-11
8-9
7-10
8-9

Exhaust

9-8
9-7
9-12
8-12
8-8
9-7
8-7
9-7

Different feeler guages than last check though. Hard to believe its lost clearance some places.

Cam manufacturer quotes specs of 8 for intake and 9 for exhaust.

Anyone have any ideas?

Dann

Hi Dann,

There is not enought difference between cheap feeler gauges and expensive ones to make the sort of difference that will cause a large noise (within reason! A half decent set should be fine).

Couple of questions.
Are you setting them hot or cold?
What shims did you fit, and did you regrind them or get new ones to set the clearance?
What does the surface on the cam lobe and shim look like? Any abnormal wear?

Cheers
Woz

There is not enought difference between cheap feeler gauges and expensive ones to make the sort of difference that will cause a large noise (within reason! A half decent set should be fine).

This is what I thought they are just stamped out of a specific thickness sheet right?

Couple of questions.
Are you setting them hot or cold?
Well this is my first though. Last time was hot hot. This time warm. I need to call Waggott cams and ask if they set them hot or cold.

What shims did you fit, and did you regrind them or get new ones to set the clearance?
They are mazda shim over buckets. I didnt build the head so im not sure about the shims. If I remove one will I see obvious grinding marks underneath it?
What does the surface on the cam lobe and shim look like? Any abnormal wear?
I can still see all the machining marks on the cams. The shims look ok. Normal wear marks on them, theyve all been spinning freely also.

Thanks heaps,
Dann

NitroDann wrote:There is not enought difference between cheap feeler gauges and expensive ones to make the sort of difference that will cause a large noise (within reason! A half decent set should be fine).

This is what I thought they are just stamped out of a specific thickness sheet right?

Couple of questions.
Are you setting them hot or cold?
Well this is my first though. Last time was hot hot. This time warm. I need to call Waggott cams and ask if they set them hot or cold.

What shims did you fit, and did you regrind them or get new ones to set the clearance?
They are mazda shim over buckets. I didnt build the head so im not sure about the shims. If I remove one will I see obvious grinding marks underneath it?
What does the surface on the cam lobe and shim look like? Any abnormal wear?
I can still see all the machining marks on the cams. The shims look ok. Normal wear marks on them, theyve all been spinning freely also.

Thanks heaps,
Dann

Ok, they need to be set hot. Any reputable cam manufacturer quotes hot.
Pay particular attention to the finish on all of the lobes and shims when you're checking them.
If your shims have been reground the new surface should always face down (away from the cam).
It is possible that your valve train has simply settled and they need redoing. Athought they usually would tighten up, it is possible that when you first checked them that the shims hadn't settled properly in the bucket, now they have, hence the wider clearance (lets face it we're only talking .004").
If you tappet noise is very loud, then I'd be concerned the problem may be something else, but you're right to start here. Measure them again HOT and see what you come up with. If you need new shims I have access to them.

Cheers
Woz

Awesome. Ill do that now.

Also, im about to PM you.

Dann

I've been doing motorbike valve clearances with a $20 repco brand feeler gauge all of my bikes for the last 3 years and haven't had any problems. There should be any difference between cheap and expensive gauges.

Ok at about 100c

Intake

9
10
10
10
10
10
9
9

Exhaust

7
9
9
10
14
14
8
9

So now we can see the issue huh.

What would be causing this?

Interesting they are side by side and equal.

Retension the cam caps?

Thanks heaps,
Dann

NitroDann wrote:Ok at about 100c

Intake

9
10
10
10
10
10
9
9

Exhaust

7
9
9
10
14
14
8
9

So now we can see the issue huh.

What would be causing this?

Interesting they are side by side and equal.

Retension the cam caps?

Thanks heaps,
Dann

Ok, the inlets are fine, I would call that within tolerance.
I would only adjust the exhaust clearances on the .007", .008" and both the .014" items. Interesting the .014" are on the same cyl. Would there be any reason they'd be bent?? Anyway, fix them and see if it cures the problem.

PM sent also

Cheers
Woz

Awaiting your latest PM.

Ok how much do I need to spend to get a micrometer good enough to measure these in order to order new ones?


You have been great thanks,
Dann

NitroDann wrote:Awaiting your latest PM.

Ok how much do I need to spend to get a micrometer good enough to measure these in order to order new ones?


You have been great thanks,
Dann

Last time I did mine I actualy used (very carefully and because I couldn't find my micrometer!!) a digital set of vernier callipers and they did the job! There is some reasonably cheap micrometers floating around, good enough to do what you're doing. Have a search on the net, I'm sure you'll find someone selling them

No probs
Cheers
Woz

spikes wrote:I've been doing motorbike valve clearances with a $20 repco brand feeler gauge all of my bikes for the last 3 years and haven't had any problems. There should be any difference between cheap and expensive gauges.

yea iv used non super expensive gauges on bike motors too though i recall having to check clearances stone cold?

aviper4u wrote:

spikes wrote:I've been doing motorbike valve clearances with a $20 repco brand feeler gauge all of my bikes for the last 3 years and haven't had any problems. There should be any difference between cheap and expensive gauges.

yea iv used non super expensive gauges on bike motors too though i recall having to check clearances stone cold?

I've always done my valve clearances hot. Yes it hurts and its a bitch getting in tight spaces to remove injector banks and stuff but a good set of mechanic gloves has always been real handy

Those clearances seem excessive when the engine is hot. On my bikes the clearances are set cold and are about 6 thou on the intakes and 10 thou on the exhausts

After a bit of research It seems that they should be set cold like other engines, 8 thou for the intakes and 12 thou for the exhaust.
Have you changed the cams? This would explain the problem