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Topic Summary

Posted by: JohnK
« on: May 29, 2020, 09:56:43 AM »

You're right of course Bruce - end play has turned my brain to mush.  For some reason, I think adding shims would decrease it.  That would indicate that I need to add shims to the camshaft.  No one sells those that I can find but I can probably get something from McMaster.  To reduce the end play of the crank, it appears that I will have to dress the thrust washer.
Posted by: Bruce_W
« on: May 28, 2020, 10:42:59 PM »

  You are aware, of course, that adding shims will increase the crankshaft end play, right?
  BW
Posted by: JohnK
« on: May 28, 2020, 01:57:31 PM »

Well, finally back at it.

cam end play with new cam = .002 -.003  better than none but still out of range- still playing and researching.

current Crank end play = .025  , way out from the .004 - .006.  That's going to about 10 .002 shims at 7 bucks a piece.  McMaster Carr has a many in stock for less.   Stainless - the best fit for diameter would be  35 mm , the ones from Kaiser would be about 1.29 inches = 32.766
the OD should be 2"  = 50.8 mm   , these would be 45 mm = 1.77".  Anybody have an opinion on those differences in ID, OD affecting the crank.

Secondly, I can buy these in many thicknesses - thoughts on how many to use   i.e. 2 .010's, vs 10 .002's, vs 5 .004  ........

Thanks in advance.

John
Posted by: JohnK
« on: October 25, 2019, 11:10:47 AM »

I have thought about this a lot and haven't really come up with an answer.  Yesterday, I received the new camshaft from Peter Debella. It certainly looks old and will take a bit to clean it off. 
Posted by: oldtime
« on: October 25, 2019, 10:12:17 AM »

One reason I suggest light surface sanding of the thrust plate is to eliminaqte the possibility of it being warped/ distorted.
The only other thing I can imagine is that the OAL of camshaft is too long and its hitting at the back side of the cam bore.
Posted by: JohnK
« on: October 22, 2019, 09:54:27 AM »

Yes Bruce, I am of aware of that fact concerning the front bearing journal.  I was just noting that difference as well.  The distance from the front of the journal to the end of the shaft was shorter on the cam that showed no end play.  In addition, Once I saw the back side of the gear, I replaced all the offending bolts on the engine plate and thrust plate.  However, you certainly are correct - excessive size of the bolt heads would cause that problem as well.
Posted by: Bruce_W
« on: October 21, 2019, 10:50:34 PM »

  The width of the front cam bearing journal has absolutely nothing to do with it. What matters is the distance from the front of that journal to the back of the gear when installed, compared to the thickness of the thrust plate. You have already (more than once) determined that that distance (set by the thickness of the spacer) is .006" more than the thickness of the plate.
  The problem appears obvious to me - the upper bolt on the thrust plate has an overly thick head or is not seated properly against the plate, and the backside of the gear is rubbing on it. When you tighten the gear retaining bolt, the gear contacts the bolt head, which prevents the gear and shaft from moving back, and at the same time pulls the camshaft forward against the thrust plate, which prevents it from moving any further forward. Hence, your ".000" end float. Try turning the camshaft and gear until that bolt aligns with one of the holes in the gear, and see if you have end float then.  BW
Posted by: oldtime
« on: October 21, 2019, 12:07:09 PM »

Be aware that NOS is an abused term and it often means your actually getting NORS.

Yes just wiggle the tappets in their bores for comparison and that will tell you what you need to know.
Posted by: JohnK
« on: October 21, 2019, 11:42:15 AM »

I see some NOS advertised but have to check on whether they are really available- if one is that's what I'll get.  If NOS is not available - I see Omix, Melling, and Sealed power replacement shafts - but I think I will stay away from the Omix based on past experience with some of their replacement parts.

Regarding the tappets, thank you for that tip since I now have two complete sets to choose from and I should be able to select the best serviceable ones that fit snugly into a bore.

Thanks to your help, I will hopefully get the engine back in before the snow starts coming down.

Posted by: oldtime
« on: October 21, 2019, 10:49:41 AM »

30 years ago simply implies the camshaft to be New Old Stock (NOS)
It could be either New Old Replacement Stock (NORS) or OEM NOS.
IMHO  OEM NOS parts in good storage condition are always the most desirable.
No upgrades nor changes for the F-134 camshafts.
Good condition used tappets are fine so long as they fit snugly to the tappet bores.
If the tappet adjuster tips have ridges from valve stem contact then they can be reground to a smooth surface.
I once had an OEM NOS set of F-134 tappets but I actually opted to use a refurbished set of used tappets because the used tappets fit more snugly into the tappet bores.

Solution...
I highly suggest you place the bronze thrust plate on a flat machined iron table  (like a table saw)
Then sand it by hand using a random orbital motion.
Use 220 grit paper and take a few thousands off the thickness.
Posted by: JohnK
« on: October 21, 2019, 10:16:57 AM »

In case anyone has insight on camshaft markings:

original 800517  C  H15  CW0 (maybe)  4
replace 800517  C  J12   CW0  (maybe) 1

original pic 1965, replacement 1968

Posted by: JohnK
« on: October 20, 2019, 08:51:32 PM »

You provided the answer a few posts ago.  I reinstalled the old cam and now have the end play.  Looks like the distance from the end of the shaft to the bearing side is shorter on the replacement - not having the experience of a machinist, it's a little tough for me to accurately measure with my caliper.  But it looks like they are different and the re-installation of the old cam seems to confirm it. I wonder if there was a change in camshafts along the way, the block and cam came from a Jeep Dealership in PA that closed 30 years ago and the block had never been reworked. So I tend to think it was an original.
I was using the matched tappets that came with the replacement shaft.  I'm guessing that you would recommend new tappets along with the new camshaft.  Correct?

Thanks for your assistance, I really appreciate it.

John
Posted by: oldtime
« on: October 20, 2019, 03:49:37 PM »

IMG_1947.JPG (2808.29 kB, 3264x2448

The foreward edge of gear hub can extend out from the end of crankshaft.
The aft edge of gear hub  must be seated against the spacer /shims.


IMG_1949.JPG (4657.54 kB, 3264x2448
Yes that certainly appears that the thrust plate bolts were rubbing.
Either too thick of heads or use of lock washers could feasibly cause that.

Quote
So according to the service manual my thrust plate and spacer are perfect and I should be able to torgue it all down and all will be well

Yes I agree.

I'm not sure yet what the problem is.
I've never seen this before.
Be patient and I'll try to figure this out.
You simply can't run it with zero camshaft end play.

So is the front of the block perfectly flat , including the area where the thrust plate bolts down ?
Is the thrust plate perfectly flat and smooth or does it have mild gouging / striations ?
Posted by: JohnK
« on: October 20, 2019, 01:01:26 PM »

It is hard to not confuse things when you are confused.

Section D-53 of the service manual:

"End play of the camshaft is determined by the running clearance between the the rear face of the camshaft gear and the thrust plate and is established by the spacer thickness.  The standard clearance is .004 to .007 and can be measured by a dial indicator.  As a general rule this clearance will change but little through wear or when a new gear is installed.  To predetermine the correct end float with the gear, spacer, and thrust plate removed, measure the thickness of both the thrust plate and the spacer with a micrometer.  The thickness of the spacer should be approximately .006 greater than that of the thrust plate.  When this is correct and the parts are assembled and drawn tightly together by the gear retaining sccrew, the end play should come within standard limits".

My spacer to thrust plate difference is .006 exactly.  When I draw the gear onto the shaft and tighten to torque spec - a dial indicator shows 0 end play. - four times over I have done this procedure resulting in zero float each time.  This is where I am confused - as you see from the prior post picture, the gear hub is not completely on the shaft when torqued down and no float is shown by the dial indicator. Obviously, the torquing of the gear sccrew (bb software won't post the correct spelling) continues to push the gear further on to the shaft until the hub is fully against the spacer.  Hence no end play float - the plate stops outward movement of the cam, while the gear prevents inward movement.

Take a look at the picture below noting the rotary scuff marks on the cam facing side of the hub - this is a new gear with less than an hour of running time on the engine.  ( again for those unfamiliar with my embarrassing end to a years long rebuild - yes I cracked the block on a freshly rebuilt engine (not by me) after less than 1 hour running time).   During the tear down of the old block, I have identified some disappointing discoveries of a less than professional rebuild.  I suspect the scuffing shown is likely due to improper engine plate bolts used rather than camshaft end play.

So according to the service manual my thrust plate and spacer are perfect and I should be able to torgue it all down and all will be well - 
with the exception that a dial gauge measurement referred to by all the manuals and OT shows zero end play.  Could I have an incorrect cam gear that has too wide a hub?  Maybe someone has a gear they could measure for me?  but a look up shows it to be a Cloyes 2900 - Fiber Timing Camshaft Gear that should be correct.

Please forgive me for beating this subject to death and my unabated confusion. But after 10 years of money and many, many long hours - I want to be able to drive the willy's and not be back removing an engine for the third time, and rebuilding it for the second.

Oh and finally, I haven't seen anybody selling camshaft shims.
Posted by: oldtime
« on: October 19, 2019, 06:33:51 PM »

Don't confuse things... .006 end play measures .006.
Your camshaft should have correct end float within the specs given.
Torque the gear down to 35 ft pounds as stated.
Forget about the thickness difference between your thrust plate and spacer.
Just add some round shims (about .005) under the spacer and get the end float to read .005 or so.

Or else you could sand the thrust plate down about .005".
It's perfectly acceptable to sand down the bronze thrust plate especially if it has any mild gouges upon it.