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Waterloo · 10-20-2017, **(Subject: CM-871 Overhead... )**

Going to crack this thing this afternoon, I hope. I keep finding more and more to repair or fix on this thing. I have the print out from Cummins, tools, torque wrenches, crowsfeet, 7mm feeler from Cummins, etc. anything else change since Rawze made his overhead video?

Hammerhead · 10-20-2017, **(Subject: CM-871 Overhead... )**

Not really. Mr Hagg showed Rawze that a slight increase in clearance resulted in increased overhead oil flow at operating temp. I don't have the thread to link, but I'm sure someone will be along shortly. I Believe the recommendation was 0.015 & 0.028.

I use a personal slight increase of clearance for improved overhead oiling.
I do 0.016" intake in place of 0.014", and 0.030" exhaust ipo 0.027". I do this because of my torque loading, I suspect my valvetrain sees extended heat so I suspect extra expansion. When I climb big hard pulls I can still hear the clicking in the valvetrain which tells me I still have good clearance during high heat cycles, and that's what I'm looking for. QS procedure says to "make all measurements with engine cold. Coolant at 140 or below." I do mine at dead cold overnight sitting, which is also why I use the clearances I do, take that into account in your determination.

I use 4 torque wrenches, just because I have them.
I set them as follows;
1)Dial tourque wrench w/ 8mm Allen, needle set to 8Nm (71 in/lbs, but Nm is easier to read)
2)1/2" torque wrench w/ 24mm socket to set @ 55 ft/lbs
^these two are for the injector preload and jam nut^
3)3/8" torque wrench w/ 19mm flare nut set to 33 ft/lbs (valve jam nut)
4)1/4" torque wrench w/ 13mm flare nut set to 177 in/lbs (Jake jam nut)
I prefer flare nuts to crows feet, less chance of slipping off, but use whatcha got.

I have T handle Allen wrenches, the 3 sizes are;
1)8 mm for injector
2)6 mm for valve adjusters
3)3 mm for Jake adjusters
I use just my thumb and pointer finger rolling motion on the shaft of the Allen to set the adjuster, that is about the 5 in/lbs they say to set the adjuster tension at for lockdown. After lockdown I do a slide test for resistance to verify I don't have the tension too tight. You should be able to move the feeler without force.

Of course a 3/4" with short extension, to bar the motor over.
I got one of these dual feeler holders which are nice because the color coding makes identifying which one I have/need easier.

I always do 3 pressure squeezes on everything to ensure the oil gets squished out to do a proper adjustment.
That's how I do it, and here is a pic of what I use...plus whatever you need to remove for access on your model of truck of course

You have my number, give me a shout if you need to...

dhirocz · 10-20-2017, **(Subject: CM-871 Overhead... )**

That pretty much covered it. I ran mine at 0.015"/0.028". No additional noise, seems to like it, especially with the gear oil.

If I had to climb more than I already do I would have opened up the exhaust a bit more but nowadays my pyro RARELY gives over 450. Prior to @m*m^2, I was seeing 800+ deg.F...

If you need crossheads, and injector or valve guide seals, now would be a good time, IMHO. Don't forget to inspect those cams while you are at it.

I'm going to be checking mine again prior to my next oil change. I'll be checking the condition/wear of the head while I'm at it.

Waterloo · 10-21-2017, **(Subject: CM-871 Overhead... )**

Thank's guys! This is the first attempt at this, and Hammer, nice setup in regards to the tools. I would like to put together a little dedicated kit like that and keep her in a separate bag just for overheads. Hammer, where did you get those feeler gauges? The exhaust and intake ones? I already have the 7mm from Cummins.

Dh, top end is fresh, but will be scoping her out for sure. Can't wait to finish this, hell start this! LOL! I keep finding more things to fix!

I was looking at my ThermoKing APU yesterday, she is about ready to fall off the truck, rotted out case. I went to put the lid back on her and a huge chunk of panel fell off into the compartment. I called ThermoKing yesterday and they will be installing a new Evolution model in the next week or two.

When I get this overhead done, than I need to run her up to the TA for a new set of brake shoes on the rear axle, trust me, it will be much faster if they do it, getting sick and tired of wrenching on this thing, LOL! Been busy around here... It never ends.

Hammerhead · 10-21-2017, **(Subject: CM-871 Overhead... )**

Thanks, it's not really a dedicated kit, I've just done enough overheads that I know what tools I need so I just popped them out for a pic for an example.

I got the feeler kit from my Snap-On guy.
It is not a Snap-On tool, but something else he carries, and when I saw it I could see the convenience of it.
It is a Lang Tools product, Part # 3079 Feeler Guage Set for Heavy Duty Truck Valve Lash Adjustment
I'm quite sure it could be found online for a better price than from a Snap-On guy, but he had it on the truck that day, so impulse said "You waaaant me Hammer..."

It comes with all pictured;
-the long blade 90* (which it says "especially useful with Cummins")
-the short blade 45* (which I prefer for an ISX)
-the second set of short blade 30* are "stepped" 0.002" (which it says is DD spec)
I never check mine, I just adjust everything, but I assume the stepped would be great for checking if someone was into that.

Waterloo · 10-21-2017, **(Subject: CM-871 Overhead... )**

Hammer, I just popped the top on this thing, and just poking around, I tried to get a .014 feeler between the intake arm and rocker, no way was that going in there, tried a few other thinner, down to .008 and could not get them in. And, both rockers are lose, so I now #1 clylinder is set properly. #6 has one lose rocker and one tight...

Is this normal? High School was the last time I messed with valves, and I cannot remember what I had for breakfast. Seriously. LOL!

hhow55 · 10-21-2017, **(Subject: CM-871 Overhead... )**

(10-21-2017 )Waterloo Wrote: Hammer, I just popped the top on this thing, and just poking around, I tried to get a .014 feeler between the intake arm and rocker, no way was that going in there, tried a few other thinner, down to .008 and could not get them in. And, both rockers are lose, so I now #1 clylinder is set properly. #6 has one lose rocker and one tight...

Is this normal? High School was the last time I messed with valves, and I cannot remember what I had for breakfast. Seriously. LOL!

Can you call me?

ktbtrucking · 10-21-2017, **(Subject: CM-871 Overhead... )**

When I made it first time and it is really difficult to put feeler gauge between crosshead and rocker. I had to wobble crosshead a little to get a chance to put feeler gauge. Like oil sticks those two parts together and also tried smaller fillers with .

fargonaz · 10-21-2017, **(Subject: CM-871 Overhead... )**

Less clearance isn't a good omen.