Now I know what the "F" in B230F stands for!

Boy did I say the "F-word" once or twice today. Bob, the tool you
showed me for depressing the valve springs was exactly what I could
have used.

OK - here's the deal on my valve shim job today:

1) The plan: measure the existing shims to match the clearance
measurements I have. Plug these into the formula to determine what size
replacement shims to buy on Saturday.

New Shim Size = (C-A) + B

C = original shim measurement
A = Spec clearance (.40mm)
B = Measured clearance

It is important to note the parenthesis because should you do C - (A+B)
you get a different number.

So - my formula will be: (4.00mm - .40mm) + .508mm = 4.108mm
I'll buy 4.10 mm shims.

Here is what I didn't like about this job and so I am going to take a
calculated risk.

All of my clearances were measured at .508 mm on cylinders 1-3 on all
valves. Cylinder 4 measured .457 on each valve.

I was only able to measure the first 3 shims (cylinders 1-2, valves
1,2,3) because I did not have great tools to work with. Each shim
measured 4.00mm. My vernier caliper was incremented by 1mm, so I made
sure it wasn't 1/2 mm off by eye.

Because the first 3 cylinders (6 valves) all had the same .508
clearance, and the first 3 valves were all the same 4.00mm size, I am
going to assume the next 3 shims are 4.00mm.

That is the calculated risk. To be sure, after I replace the shims I'll
take measurements to ensure I am within the .30 - .40mm cold clearance.

I don't think I will do cylinder 4 at this time because I am not able
to measure the shims. My plan is to drive 1.5 hours to the Volvo
dealer and buy the shims I need. I will not have a kit.

I may just buy that valve spring tool though. It is a pain using a
screwdriver. I had to turn the camshaft to depress the springs, insert
screwdriver, turn cam to release the lobe and hope the screwdriver
held. Sometimes it did. Sometimes it slipped off.

Jamie

 

Bob,
I've decided to order the Tappet tool along with my shims from FCP
Groton. I've decided to make my life a bit easier and have the right
tool.

 

Are you measuring the shim or assuming it is 4mm?

The formula could also be (B - A) + C

You could also just mike the total distance and subtract the required
gap.

Check EACH valve.

Not a good risk to take. If you don't have the time and equipment to
do it right then have someone else do it.

See above.

 

I physically measured 3 of the shims. Once I receive the valve tappet
tool in the mail I will pull and measure each shim and recalculate.
Because I had no tool, I could only get 3 off in about 2 hours.

Because the 3 shims I measured with my caliper were all 4mm and the
valve clearances for the 3 cylinders were all .508 - I will order all
shims to be 4.10mm per the formula.

Here's how I see it in the end:
I'm going to get the right tool in the mail and a set of shims with it
based on my risk. When I pull each old shim off I'll remeasure and
recalculate. If all of the shims I ordered are the right size, I'll
install them. If not, I'll send back the unused/unopened shims and
drive to the local dealer and get the right size.

Now that I have a tool on order, I can make sure each shim is measured.


BTW: the shims in my engine had no markings. Do they wear off after a
while?

 

To save yourself some driving you might want to order some shims plus
or minus one and two sizes from your estimate. Just return the unused
ones.

 

Thanks, good point. The last 2 valves measured .5mm less clearance, so
I might order a few shims + or - .5mm.