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460 Cam /Lifter Failure Again, HELP!
I have now lost my second engine and third cam in a Ford 460. All failed in less the 100 miles. Lifter ground down and cam lobe.Not sure what I am doing wrong.
First Engine had Comp Cam and Lifter. Wiped out 6 lobes and lifters in 60 miles along with the crank. Second engine was a Ford SVO short block, Ford .588I,614E cam with Ford SVO lifters. Heads are SCJ Alumimum with Sharpe roller rockers. Spings are 130#closed, 375#open. Used the oil additive for breakin and moly on the lobes and lifters. Primed engine and ran at 1500 RPM for brake in. 2 years, 3 engine pulls and less than 200 miles on the car, Frustrated! Do I need to go to smaller cam, lighter springs, roller cam/lifters? Ideas? |
duke,
You might have some good experience to draw on if you also ask that question here: http://www.460ford.com/forum/ and here: http://www.429-460.com/forum.htm There are quite a few things that can cause that problem, like assembly lube, initial clearance adjustment procedure, oil passage, pump or pressure problems and so on. Wish I could help! Tom |
My best advice is to let someone else build it, so if it breaks again it's on their dime.
There are a lot of things that may have caused it. Not breaking in your cam right is probably the reason. You should rev it to 2000+ RPM for 20 minutes. If your heads have dual springs, you should take out the inner springs to reduce some tension. You need to use the right oil as well, like Valvoline racing oil and a bottle of Comp Cams Break In lube. Good luck with the next one, Joe |
There is certainly an art and science both to breaking in a flat tappet cam.
For this time around though, I think I would just bite the bullet and put a roller camshaft in it. A hydraulic roller will give you a zero maintenance, zero effort on break-in. If you want to try a flat tappet again here are some pointers: 1. Make sure that all lifters will rotate easily in their bores. 2. Remove the inner valve springs or use break-in rocker arms. 3. Use lots of cam lube on the camshaft and lifters. 4. Use a good break-in oil, such as Brad Penn or Joe Gibbs. 5. Set the timing and carb so that it fires immediately. 6. Run at 2000-2500 for 30 minutes. With the loss of the third camshaft, my first advice would be to just put a roller camshaft in it. No worries. |
Duke, where are you?
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Double check the push rod length. One of the members of our local club was having multiple problems all traced back to incorrect push rod length.
DonC |
Fill filter with oil prior to firing and prime system for about 1 minute to insure oil is EVERYWHERE, and as previously mentioned keep RPMs at about 2000 for initial 15-20 minutes.
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Sounds to me that that many failures over that short of a time would indicate the problem lies elsewhere, and the cam failure is just the result.
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Thats kind of what I was thinking.....3 cams and crank...probably all in the same block. Check the lifter bores and line bore the block. Taking out the crank...thats a problem I would really look into. Need to check the crank centerline as well. Just to make sure its not off. I have a 460 for sale. 4 bolt main block, stock football rods, TRW flat tops,high 600's or low 700's solid lift flat tappet(dont remember the lift). c9 or c8 heads...would have to look to make sure...pre smog though I know that much. Offenhauser spreadbore intake...no carb or distributor with motor. Motor has about 20 to 25 passes since it was built. Broke a tranny and bent the chassis on the dragster so we quit racing. Motor has been sitting ever since. |
460 motor
Duke,
I too had my first 460 motor that crapped after about 300 miles. I found a guy named Arron Johnson at Bad Ass Racing that built me the 460 motor (actually a 522 now) I have now and it is truly awesome. Arron also has a complete line of power building videos that he has prepared and distributed. I don't know of anyone who knows more about engines than him. He also builds and ships motors all over the country. Check his web site out at www.badassracing.com Mike |
I located in Southeast Wisconsin.
Tried two cams in the first block then had a new short block built up assuming there was a alighment issue. Transfered the heads and intake. Did check the push rod length after the first failure. |
A severe loss of a cam can take out a crank by allowing the oil pump to pump metal shavings throughout the engine. Metal shavings in the oil feeding the main bearings will cause a lot of problems.
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There are a lot of sub par lifters in the market place too. Improper heat treat and soft materials. Choose wisely. I have also noticed that Comp Cams is offering a tufftriding process now for their cams.
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Yep, you can have the cams nitrided. I can still get some Schubeck lifters too.
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Thats the M-6513-A351 flat tappet spring package in the SCJA head.
Unless you got SCJB's by mistake, they run a beefier spring (Comp #953) for smaller solid roller cams. I think im with Mr Hall on this one Have you verified its oiling thru all the lifters? Jason |
The spring pressure is to much for sure on break in. You need break in oil with everything lubed before starting. You will need to remove the inner springs at least. We like to break the camshaft in with about 80lbs on the seat and no more than 280lbs over the nose. I would run no more than about 130 on the seat and about 330 to 340 over the nose. Must run the engine with the break in springs for about 30 minutes at about 2000 to 2800 rpms. You will then check to make sure that you have not lost a lobe at this point. If all check out well add the inner springs and run another 15 minutes with the new pressure and re-check.
This is one reason we run a lot of hydraulic roller camshafts. They are more money but in the end are they? Just let us know if we can help. Do a lot of stroker 460 style engine that work great and make 600 to 700HP on pump gas with a hydraulic roller camshaft. Thanks, Keith Craft |
Cams
I think Carl is on the right track. I mention to check the geometry, from the lifter, push rod, rocker, valve stem and spring. I haven't encountered it very often but you could have SPRING BIND.
With the the valve all the way open and the lifter on top of the cam lobe and the rocker to stem clearance set (valve lash) check the clearance between the coils on the valve spring (inner & outer) 360 degree, top to bottom. Start .001, .002 etc. (between the spring coils) Rotate the engine a few times and check each one.(intake & exhaust) Without knowing all the spec's on your engine, I can't give you the exact clearance between the spring coils. Also check spring tension. I figured you have done that. Good Luck:) |
Agreeing with the group to an extent. I build a lot of flat tappet engines, and follow procedures religiously for break in. So far we've only had a couple go down over the past five years, and they've been traceable to secondary issues - one was not properly broken in, another filled the crankcase full of gasoline from something that got into a carb.
Are you using a double spring? If not - you should be. A single sping with those presures will kill you. I don't have a problem with the pressures shown, but they are too high for break-in. Pull the inners - a PITA - but necessary. Like they said - look for mechanical interference - retainer to guide, retainer to valve seal, pushrod binding against guideplates or rubbing on heads, rocker binding, coil bind, etc. I'm not the biggest fan of hydraulic rollers in 460s due to the short pushrod/angularity issues unique to this engine - but they are an effective solution to this problem on a street piece. |
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