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MG TD TF 1500 - Good Cam?

I came across this cam in my spares. The lobes look good, but how do you evaluate a cam without sending it to a shop?



Bruce Cunha

Here is a picture of the lobes. All look pretty much like this. Not flattened.

Bruce Cunha

The lobes look rather pointed, which suggests it is the 168553 camshaft.
R WILSON

Cams wear in two dimensions: the lobes begin to break down, and the lobes get shorter.

Breaking down lobes are also easily identified, visually. The ramp of each lobe should be smooth and polished, with no uneven wear marks, grooving or damage to the surface. If there is any such damage to the lobe, the cam is bad and should be replaced or re-ground.

If there is no lobe damage, the lobe height can easily be measured with a mic; all the exhaust and intake lobes should be within a few thou of each other, in height.

There is no history of cam bearing surfaces wearing, so as long as the distributor and oil pump drive gears show no damage, that's it.

Tom Lange
MGT Repair
t lange

Thanks Tom. Easy to measure. The lobes are very smooth. I see no areas where one has less point than the others.

I will do a height measurement and who know's I may have a good spare.
Bruce Cunha

I agree with Tom. I have found that worn camshafts tend to have different amounts of wear on different lobes. I once measured a cam which at first appeared to be unevenly worn, but when I subtracted the base circle from the total height (from the back) the lifts were only a few thou different. I put that cam into my race TC when the NOS 168551 cam chewed off its oil pump gear about 23 years ago.
Bob Schapel
R L Schapel

I measured the lobes. The tips are smooth without pitting. The lowest is the lob towards the back of the oil pump gear at 0.217" The highest was 0.233", so a difference of 0.016"

Bruce Cunha

This thread was discussed between 08/11/2019 and 14/11/2019

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