I think I just lost a lobe on my cam, I am not sure why?

[Anonymous]

Its been a while since I have been on here. I just got back from Hot August Nights last night. I had about 5800 since my rebuild before I went on my 1300 mile round trip. I changed the oil and converted to Mobil 1 before I left. The engine has a Comp 260H cam with an adjustable rockers. Went I got to Reno I heard a little lifter tick. When I got home last night, it was very loud. I pulled the valve cover this morning and found number four intake to be loose. There was no adjustment left on the rocker nut. My machist says I probably killed the lobe on the cam since it is so loose. I have yet to pull the head and verify. I am a little disturbed to why this happened???

I like the cam performance and how it makes the exhaust sound but I have had issues with it since day one. I was never able to get the cam to degree properly from the day I bought it. I even sent it back to them for them to check it out. Of course they found nothing wrong. I ended up running out of time and just used it as is. When adjusting the valves, I most of the adjusting nuts were close to running out of thread. I adjusted them three or four times before I started the car and twice after with no real change in adjustment. This has always bothered me since i built the motor

Anyone else have trouble degreeing this cam? What are the common caused of lobe loss? Adjusting the valve too tight? What does the roller rocker assy cost these days? What else has to change? Pushrods? Would I be able to use the roller rockers with this cam without changing my valve springs? Is there a better cam out these days?

I don't know what I am going to do if my cam is wasted. I put a lot of time and money in this engine a couple years back and really don't want to have to go thru all this over again

 

[addo]

I understand that soft cams are a documented occurrence. You may get some warranty "mileage" out of the maker if you put your case well enough. The degreeing aspect is really one the manufacturers should address but a good timing set removes any uncertainty.

Many times I see people posting here that they can't get their rebuild to fire up. They are cranking and cranking, and all the cam lube is wiped off way before the motor fires. Dialling the lobe lifts will tell you if there is any loss of material on your cam.

Regards, Adam.

 

[48fordnut]

Addo,you are correct about one of the reasons lobes are lost. If the eng dosen't grank in 10/15 sec some thing is wrong. fuel and firing should be verified before turning eng over, so should oil pressure. jim.

 

[addo]

If you put the head on with #1 at TDC firing, then nothing needs to turn before startup. You can even adjust the rockers without turning it as the cam is new and even, the valve tip heights measurable and all pushrods the same length.

I'd like a motor to start on the second or third compression at #1. Why shouldn't it?

 

[wsa111]

Tigger, sorry to hear that bad news of a wiped camshaft.

Life must go on, get your next camshaft from mike, www.fordsixparts.com
I suggets the 264 grind in a 112 lobe center if you want a smoother idle, or in a 110 lobe center for a rougher idle.
Get the correct springs for the camshaft from FSPP, this cam has a much faster rate of lift than the comp cam & needs 80# plus spring seat pressure to eliminate valve float.

Buy the camshaft & lifters, & springs as a package, do not mix manufacturers.

When you install the cam use moly lithium lube especially for camshaft breakin, put the lube on the cam & lifter contact surfaces, also get a can of EOS-engine oil suppliment from a GM dealer for camshaft breakin lube, just add it to the oil before startup.

When you start the engine bring it to 2500+ rpms for 15 minuites to breakin the camshaft to lifters.

then change the oil & proceed to take it out and run it, do not let the engine idle during the breakin period.

Do this & you will not wipe a camshaft again.

The comp cam is a very weak camshaft in the rate of lift, thats why it only requires 50# of seat pressure. Put in a mans camshaft from FSPP & enjoy the power increase. William

 

[rickwrench]

Check to see if the bottom of the pushrod is crushed/wiped out or if the lifter is collapsed first. Hopefully, it's just a lifter.
Rick