htr

Well-Known Member
For those who remember this is about my winter project from last year!

Yesterday I got that head back from the engineers :) They replaced some valve seats and checked and 'trimmed' the valve stem heights. It just requires a light clean, reassembly and it should be good to go. We talked about cleaning and testing hydraulic lifters. I've cleaned my set and some were corroded on the crown when I acquired the head so I discarded those ones [3]. I've got spare sets from other dismantled heads so I picked 3.

The ones I chose came out of an overheated head. I felt that the springs inside the valve body of the lifters were softer that the good head so I swapped the springs over in the 'socket & plunger' assemblies. I noticed that the body of the replacement lifters has some scoring and blackening but otherwise appeared OK. My engineer suggested that along with dismantling & cleaning the lifters I should check their operation before installing and told me how to do that.

Reconsidering my choice of replacement lifter I was wondering if there was an advantage in using the set of lifters from my VVC head: the head itself is soft, 8 or so on the Brinell scale, as well as dismantled, so the lifters are right at hand. I know that they are the same diameter...

I've measured both lifters as best I can with my digital callipers. The VVC ones are about 1.6mm shorter than the MPi ones - see my sketch below.

The only thing I can think of is that it would possibly be a good idea as in the not to distant future I want to fit that VVC exhaust cam as my inlet cam. Those lifters are the correct ones for that cam.

What's the thinking, ok to swap over? Any problems you can see?

IMG_2143.JPG
 
I've got spare sets from other dismantled heads so I picked 3.

It's not advised to used second hand lifters from another head, as the lifters and cam lobes wear in together, giving a long life wearing surface. If used lifters from a different cam lobe are used, then the previous lifter wear will cause rapid wear on either the cam or lifter, or both. Which is why lifters should always be refitted in the same position they came out of.
For the sake of a few $ per lifter, you're better off replacing them, and be confident of a long life.
 
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The only thing I can think of is that it would possibly be a good idea as in the not to distant future I want to fit that VVC exhaust cam as my inlet cam. Those lifters are the correct ones for that cam.

The VVC has a higher lift, so it's likely the lifter is shorter to accommodate the extra lift. It could also be shorter to reduce weight and wear, as the VVC is designed to spin faster for longer.

However the same rules apply, use new followers, unless they're going back to be paired with the same cam lobe. ;)
 
Well I did buy brand new lifters however one or two are noisy... Kind of a mess is there a way to tell which one or should I buy 4 and replace the area I hear with Stethoscope?
It's on topic.
 

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