camshaft bearings

[HG_S-type]

Hi,

After the headgasket change last year I heard a loud noisy tapping sound.
This week I decided to measure the valve clearance. I noticed that they are to high.
So I will adjust these with the correct shims.

But I have 2 questions about the camshaft bearings.
- I took some pictures and I'm wondering are they worn and is it necessary to replace these?
- What is the correct way to remove these bearings from the bearing caps and cylinderhead?

Thanks,

Harrie

[John Quilter]

I'm no expert on bearings but these do not look worn to me. I would leave them alone.

[cass3958]

I agree with john that apart from scoring which is running with the direction of rotation there does not appear to be any wear. True wear would show up as a discolouration of the white metal turning to a copper colour as per the photo.

Bearing wear.jpg (8.77 KiB) Viewed 733 times

To remove these shells though is fairly easy. There is an indent in the shell in one corner that sits in a corresponding notch in the bearing carrier. This is so the bearings do not rotate in the carriers. If you use a punch or drift against the opposite edge of the shell and tap the shell to make it rotate towards the notch it should then fall out.

I hope that having removed the bearings and shells you made a note of which were pairs and where they fitted on the camshaft as the wear you have matches each position and to change them around will cause more wear quicker. When reassembling it would not harm to take some 2400 grit wet and dry paper and just wipe over the metal of the cams to take out any high spots. There is no need to touch the shells but you have to make sure they are spotless and clean when reassembling. There is a special lub you can buy for assembly of cam and crank shells but I cannot remember its name. Glyn might be able to assist with this.

[Glyn Ruck]

Those cam bearing are just fine. Put them back in the correct location. Make sure everything is meticulously clean.

Just assemble with plenty of the engine oil you use. You don't need any of these other things.

Make sure the cam lobes & followers are good & wet with oil after the caps are torqued.

Before you first start the engine. Keep power off the ignition & crank over until oil pressure starts to rise & you can see signs of oil at the cam journals via the oil filler cap.

[HG_S-type]

Thanks all for the response. I appreciate that a lot.
I will leave the bearings as is and I'm aware that bearing caps have to place back in the exact position.

Harrie

[HG_S-type]

Today I looked again to the camshaft bearing shells and doubt about the condition.
Because I see some discoloration although not to copper but another colour (see picture 6 and 7).
- Is it wise to replace these bearing shells anyway?
- Does it have an impact on the already measured valve clearence?

Harrie

[cass3958]

Although there are marks again I would not be too worried about them. The Cam bearings take less of a hammering than the main journals and big end bearings but if you are in any doubt a new set of camshaft shells are only between £31 and £54 for a set from SNG. https://www.sngbarratt.com/English/#/UK ... earings%60
I doubt if there is enough wear in your bearings that could cause any movement which would alter the valve clearances but if you are changing the shells then a remeasure after would not go amiss.