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Tips
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MGB MGB cylinder head

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Carlbanan56

Carlbanan56

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Hi,
I have problems with extensive oil consumption on my MGB -75 so I have recently removed the cylinder head and will be getting new valve guides installed and the head resurfaced. Will at it I thought I would be using some valve grinding paste to clean up the valve sealing surfaces. This is my very first time working with a cylinder head of any kind. Do you guys have some tips for me? Is there any part I should be buying new? I am convinced there is something I haven't thought of and will be doing wrong.

Young and inexperienced
Thank you all

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Would also check you fuel mixture.
Switch the exhaust valves to Stellite/stainless and purchase a good brand copper head gasket.
If you want more power, have the head gas flowed.
This is just a short list.
 
Looks pretty good, overall. Ditto all the above, and if were mine, I'd give the top of the block a good cleanup, also the piston tops. You might want to take a Scotch-Brite pad and go over the cylinder walls as well. I don't see any evidence of leakage between the cylinders; maybe just a tad between #3 & 4, so looks like you have good situation to work with.

However, you said you're having oil consumption, and you did a compression test. What were the numbers?

Never mind - I just did a search of your earlier posts and found them; 150# on three and 135# on the other. Not bad, but 135 is right at the threshold; rule of thumb, I believe, is a 10% difference. Do you know which cylinder that was? If so, be sure to ask the machine shop if that cylinder's valves showed any signs of deterioration or carbon buildup. #3 cylinder is most often the culprit, and #3 on your seems to look more saturated with oil a more than the others.

Great work on your part so far!
 
Unfortunately, I do not remember which cylinder had bad compression. That's a dumb mistake on my part. I was thinking I would remove the valves myself before handing it over the head to the shop. When they are done I will be using some grinding past to make sure the valves have a good seal.
 
Carlbanan56 said:
Unfortunately, I do not remember which cylinder had bad compression. That's a dumb mistake on my part. I was thinking I would remove the valves myself before handing it over the head to the shop. When they are done I will be using some grinding past to make sure the valves have a good seal.
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If it were mine, I'd let the shop do all that; I'd bring it to them intact. If you don't, they might not guarantee their work.
 
I agree with Mickey. The machine shop should be entrusted with installing the valve guides and seats, as well as refacing the seats and grinding in the valves. Look at the faces of your valves carefully. If there is any pitting or discoloration on the seat faces, replace the valves. Even if only one or two valves are suspect, replace them all. While the valves can be refaced, they will not last long. Do the job right, and only do it once.
 
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