Cam Pin Questions

[Wreckless Warren]

I have all my parts now for the stroker kit going in the 65 PI block. The engine had the molded nylon gear on an aluminum base and the pin is firmly in place, it will need to be pressed out to be reused. But I was able to see if the pin would fit the Ford Motorsport Timming Gear I have for the build. It goes in with no slop but is not like the fit in the old gear. I also test fit the pin into the Comp 270S cam and if it does fit it would need to be pressed in (maybe some time in the freezer first)

So what's the deal, I have read bad things happening associated with the pin comming out after assembly and chewing up valves or being too short for the fuel pump ecentric and needing a ball bearing to lengthen it.

Is there a replacement pin I should be looking for? Where is the interference fit for the pin suppose to take place? In the Cam or in the Cam Gear. I want to have my shit together when I take everything to the builder tomorrow. Thanks. ww

[rcodecj]

Mine have all fit with no slop in the cam or gear and you have to pull/tug on them a bit to get them out but they were not a press fit.
I have never had a problem with them that way, on  too many cams to remember or count.
Remember to get the length right, if you have to put something in the cam hole to push the pin out if it is too short, but don't get it too long either.
It should fit flush with the outside of the fuel pump eccentric so the washer covers it nicely.

Wanted to add that I don't reuse the original cam pin, I usually use a new one. IIRC the originals are a tight press fit in the nylon gear, someone correct me if I'm wrong.

[jayb]

My theory on this is that the pin is only there for initial alignment of the parts.  When you torque the cam bolt the press from the bolt is actually what should be holding everything together.  So if the pin is a slip fit, and not sloppy, there should be no problem.  The washer under the bolt should apply the force to hold it all in position.

I've read of situations where the pin has slipped back and no longer engages the fuel pump eccentric, and then the eccentric starts rotating.  To me, that indicates inadequate torque on the cam bolt.  It should be torqued to 45 ft-lbs when you assemble it.

Same goes for the front crank bolt, by the way.  The press from that bolt is what should be holding the lower timing gear in position on the crank (through the washer, harmonic balancer, crank sleeve, and oil deflector), not the keyway.  That bolt is supposed to be torqued to 150 ft-lbs, and for good reason.

JMO - flame away LOL!

[drdano]

That bolt is supposed to be torqued to 150 ft-lbs, and for good reason.

My '62 Galaxie factory service manual torque spec is nowhere near this... I dont think my "big" torque wrench even goes over 120.   

[machoneman]

Jay as usual ( !) is correct on all points. Even Chevies (oophs, used to run those too) require that the crank bolt carry the load, not the key or keyway. The same applies to the cam pin and bolt. A light fit into the cam is fine but one should not allow the pin to be too long as the the washer/eccentric  could be held up on one side.  Too short is equally bad as Jay mentioned.

[Wreckless Warren]

No flamimg here Jay but where do you arive at 150ft/lbs?

My only reference is the 1965 Ford Shop Manual and I see the 35-45ft/lbs for the cam sproket bolt. But the damper to crank bolt is spec'ed at 70-90ft/lbs for all engines OTHER than the 240ci six? The 240 is spec'ed at 130-145ft/lbs??

I bought an ARP bolt for the cam (reuse washers) and an ARP Crank Bolt & Washer.

Also, I have not opened the box for the new SCAT Crank, figured I would keep that sealed up till it got to the shop building the short block. Should I take along the new Ford MotorSports Flywheel and have them mock it up to the crank and also check the diameter of the hole  for the pilot bearing before they start assembly?

My brain always has me thinking about potential problems on things like this. ww

[Wreckless Warren]

There is a flat washer and a lock washer for the Cam Sproket Bolt but the flat washer does not cover the hole in the ecentric for the pin. If the pin is not held in with a good interference fit (as it is now with the old cam sproket) the pin could potentially fall out.  I am not missing any parts, this is the way it came apart from Ford back in 1965. ww

[rcodecj]

Ford says:
Damper Or Pulley To Crankshaft 70-90 for 390,427

from the 1967 Ford shop manual for mustang, cougar, etc

[machoneman]

Yea, for FE's it's 90 lbs for the crank/balancer bolt per my now truly ancient O.H.O. Ford manual.

[jayb]

I think you guys have got me on the torque spec on the crank bolt.  I've had 150 ft-lbs in my head for many years, and have always torqued them to that level.  But after looking it up my books all say 70-90 ft-lbs.  I wonder where I got the 150 ft-lb number?  Is this by chance the number for a 429-460?

Warren, I'm also surprised that your cam bolt washer doesn't cover the pin.  All the engines I've disassembled from '64 on have had that thick bolt that overlaps the cam pin hole.  I would replace the washer you've got with one that is larger in diameter to keep the pin from slipping out.

[rcodecj]

I think you guys have got me on the torque spec on the crank bolt.  I've had 150 ft-lbs in my head for many years, and have always torqued them to that level.  But after looking it up my books all say 70-90 ft-lbs.  I wonder where I got the 150 ft-lb number?  Is this by chance the number for a 429-460?

Warren, I'm also surprised that your cam bolt washer doesn't cover the pin.  All the engines I've disassembled from '64 on have had that thick bolt that overlaps the cam pin hole.  I would replace the washer you've got with one that is larger in diameter to keep the pin from slipping out.

Nope, 460 crankshaft pulley bolt is 70-90.
The head bolts are 140, don't know where you got the 150 number.

[jayb]

Must have been beer related 

[Barry_R]

Don't know about the beer...

We go around a hundred on crank bolts.  And 90+ percent of our builds use ARP there.

I agree on the cam dowel to a point - but I very much prefer to have them go to the outer face of the pump eccentric and be at least partially captured by the flat washer.  We use ARP bolts and our own extra thick washer there, with red Loctite and 65 lb torque.  I've had cam bolts come loose & it ain't pretty.

[drdano]

I had the supplied cam pins for both my 282s and my custom roller from Comp turn out to both be too short and would just barely be long enough to get to the ecentric.  Even the factory one I pulled from my old beater 390 cam was too short in either cam, so I almost wonder if Comp maybe was hitting the pin holes a tad deep on the assembly line or needed to ship a different pin in the box.  I ended up shimming the pin longer with a 3/16" lenth of old pin down in the hole and the "new" pin ran on top of it.  It snugged up nicely with the pin snugged up as the washer took it in as the bolt was torqued.  Probably not the best way to do it, but it appears to have worked thus far.

[afret]

For torque specs, I use the ARP torque chart.  For the Pro Series bolts, I use the 190,000 PSI tensile strength column.  The cam bolt is 7/16-14 and the crank bolt is 5/8-18.  I torque the cam bolt to 75-80 ft-lbs with Loctite.

http://www.centuryperformance.com/arp-fastener-torque-specs-spg-188.html

For a washer for the cam bolt, Mcmaster has hardened thick washers in the right diameter to cover part of the dowel so it can't come out but small enough to be able to see the dowel.  I got a box of SPS 5/16 dowels that are a bit too long and I cut them to length.   If you run an electric fuel pump, the washer that comes with a bolt kit for a SBC damper works well for use without the eccentric.  I think in the photo the washer is a .14" thick, 1 1/4" diameter hardened washer.  The washer was for a 5/16 bolt and the hole was enlarged a bit.