Replacement of oil pressure relief valve spring

[stownsen914]

Is it common practice to replace the oil pressure relief valve spring during a rebuild even if it measures within spec? Mine measures just over 86 mm (spec is 86 mm).

The safety valve spring, in contrast, is well under spec at 61 mm. Spec is 70. I'm replacing that one.

[porschedude996]

What’s the cost?

[stownsen914]

Not much, but there are hundreds of little things in these engines that we don't replace every time we rebuild them. I'm just wondering if this is one of them.

[porschedude996]

Originally Posted by stownsen914

Not much, but there are hundreds of little things in these engines that we don't replace every time we rebuild them. I'm just wondering if this is one of them.

Check that, these things do have more parts, let’s say three times as Chevy Small Block.

If find one short spring and most likely about the same age, maybe the other is about to fade???

[Cloggie]

I have wondered about this too.

My 3.4 build is based on a brand new engine block I acquired some time back for about $1000....long story.....it is a late 930 case with all the upgrades.

My concern is that the oil pressure springs have been sitting in the block for 10 years, unused, unmoved and I wonder if they are just set in their ways and need to be replaced.

Needless to say, when I get to that point I will take them out, check them, lube them and so forth with the theory that if they look and measure out correctly, they should be good to use.

....or do I just replace the frigging things on the basis of old age....

D.

[PeteKz]

This is a misunderstanding about steel springs. The oil pressure springs move very little in use and I have not heard of one failing from fatigue yet. If they measure to spec, they have not sacked, and you can reuse them. Just like valve springs, which are under far more cyclic stress.