Valve spring tests and measurements........

[boyt911sc]

I am interested in doing some valve spring tests for 911. For those of you you have done valve spring tests and measurements, what would be a good tool to purchase for a DIYer like myself. I am looking for a reliable tool that is affordable. I would really appreciate if you show some pictures of your tool and cost to buy it. Or tools that I should avoid to buy. Thanks.

Tony

[cgarr]

I use my Rimac for checking seat pressures you can usually pick up a good used one for under $500

[Neffets]

Or you can go ghetto style like I did bathroom scale and a milling machine

[boyt911sc]

Craig,

The Rimac is one of the testing tools I got my eye on but it's quite expensive. At this point, I like to spend around $300 or less. Machine shop that I've been using the last 15 years does a good job. I am just curious to know the valve spring compression settings on the cylinder heads (before & after) the machine shop worked on them.

Any techniques or suggestions how to do valve springs testing and measurements reliably by beginners (DIYers)? Thanks.

Tony

[HawgRyder]

In a pinch...you could sub Tony's mill with just a press (cheap ones are less than $50).
Bob

[cgarr]

If you want to check seat pressure use all the retainers but calculate in the thickness. Bottom one is .210 top is .070 so if my installed spring is 1.350 I add in both those and run my Rimac down to 1.630 and get about 68# of seat pressure.

[safe]

I made a rig to mount the heads on and used the shop press to push the valves with a simple gauge between.

[boyt911sc]

Thank you for all who replied and posted some pictures to this post. I am slowly getting to learn and understand how you guys do it. But I am still at a lost when it comes to differentiating a good set of springs from those out of spec. What are your basic procedures or references to make a good decision of replacing or installing new set of valve springs. BTW, the few engines I worked before had the cylinder heads done by a recommended machine shop and completely satisfied with their work. Christmas is fast approaching and I know what toy/s to ask Santa this time.

Would it be alright to ask the machine shop how and what criteria they use for their valve spring test / measurement? What criteria you guys use for such evaluation. Thanks.

Tony

[Neffets]

This is another way of doing the spring test if you don't have access to a lot of fancy tools.
Measure up the weight needed on a digital scale, put everything in a net/ bag hang it onto the eye bolt and then measure how much the spring has compressed and compare to factory specs.

All the springs on my old 1974 engine was still within spec, so I think they are of very good quality

[boyt911sc]

Originally Posted by Neffets

This is another way of doing the spring test if you don't have access to a lot of fancy tools.
Measure up the weight needed on a digital scale, put everything in a net/ bag hang it onto the eye bolt and then measure how much the spring has compressed and compare to factory specs.

All the springs on my old 1974 engine was still within spec, so I think they are of very good quality

Steffen,

So you used several different sets of weights and measured the compressed height of the springs? Could you share with us the numbers (measurements) you obtained? This is a very ingenious set-up!!!!!

For the '74 valve springs, what are the weight to height spec? Are these specification found in Wayne's 911 Engine rebuilding book? Or from some where else? Thanks.

Tony

[Neffets]

[Walt Fricke]

Magnus - do you use that nice fixture and your press to remove and install the valves also?

[safe]

Originally Posted by Walt Fricke

Magnus - do you use that nice fixture and your press to remove and install the valves also?

No, I have a home made clamp that's more easy to use for that.