rmbuilder

If possible, take some photos of the failed areas of the parts and post/send them.
Bob

KAAMA

Whitekuckle,

My cousin still has an Ultradyne flat tappet hydraulic cam for a Mark-4 block that is still brand new, unused in the box that he wants to sell. Not sure what specs you had, but the one my cousin has is a 231*/239* (288*/296* advrtsd) on a 112* lobes.

articfriends

I can't find fault with anything you did and the fact that it took 125 hours is even more puzzling! I would chaulk it up to a defect in the cam or lifter surface that took a while to fail. I have used ultradyne cams in alot of flat tappet motors,even ones with superhigh opening and closing rates with no lobe problems but that doesn't mean you didn't get a bad one. Before they went out of business i called them to order a cam and they told me they were having a hard time getting cam cores,that was about 3 years or so ago,maybe they outsourced them to a different vendor and pthers will chime in with similar problems. Your doing the right thing tearing motor down completely,sooo many people tell me about cam failures and then tell how all they did was just change cam afterwards just to have more problems,Smitty

rmbuilder

While the initial effects of spalling can be evident as soon as the break-in is completed, unless you do an inspection you'll never see the initial signs. As evidenced here you can run a significant period of time prior to catastrophic failure.
Bob

Whiteknuckle

Gentlemen,
Again, thanks for the comments. We are only able at this point to work on this engine on the weekends. We now have the heads in the shop and will examine them completely to rule out any issues with valve guide clearance or misc upper valve train issues. Of coarse the heads (Chevy 049's) will be freshened up since they are off.

Kaama, thanks for the offer, that cam you described is very close to what I had in the motor. This camshaft that wiped out was purchased about 3 yrs ago. There seems to be a common issue with the Ultradyne products purchased around that time. I think I will pass on another Ultradyne and try something else. Like I said, I'm kicking around going to a roller.

articfriends and RMbuilder, In the next few weeks when I get these parts available for photos, I will gladly share them. Like I said before, there was a least one other lobe that we did not like the surface appearance of, but the lifter looked great. As far as tearing the engine completely down, we just can't take a chance on debris in the bottom end. This thing has got to be cleaned and checked throughly.

Lmarth

I made the change from automotive to boating toys relatively recently. One of the most common serious engine problems in the boating world I've seen is folks not breaking in their cams and not doing a thorough rebuild after losing a lobe (by the way, as soon as I saw the words back fire, I said Exhaust lobe). Whiteknuckle impresses me as someone who did all the right things up front and plans to do all the right things now. Probably was a bad cam. Bob (rmbuilder) and Smitty are always on top of things. I sympathize with Whiteknuckle. It's got to be frustrating to do things right and still have problems. Lou

MESABALANCING

Whiteknuckle
A Couple Of Things To Do On The Reassembly That We Do To Flat Tappet Cam Engines It Doest Take Much Time The First Is Check Lifter Bore Clearance We Run .0017-.0022 Max The Second Check Each Lifter For Nicks These Parts Are Production Made And Many Times Not Closely Cared For At The Factory We Check Each Lifter For Crown Height And Rockwell Hardness And The Most Important I Feel We Hone The Oil Galley Bores Internally To Eliminate Any Sharp Edges Or Burs Around The Oil Hole This Is A Pain In The Ass But We Have Never Had A Flat Tappet Cam Fail Knock On Wood I've Developed This Process Through Time With My Stock Car Engines And I Can Tell You It Works Its Probably To Late To Figure Out What Happened But This Can Help You Go Forward And Have Success If You Have Any Questions On Spring Pressures Or Anything Like That That Is Critical I Can Tell You What I Run Good Luck Going Back Together Laz Mesa 1-305-884-5368

Strip Poker 388

Ultradyne . We call it kiddydyne here in Mississippi I did not know he was still in buz

I know on his race car cam shafts they had a real steep ramps on them .I dont know how he does it now or on his Marine cams. its does sound like a bad [soft] core .

Thats a hard one

Good luck
Rob

Whiteknuckle

Lmarth,
Yes it is frustrating when things that are out of your control happen. I'm glad it happened as the season was ending as opposed to the start of the season. As far as doing all the right things, we try. My son is my engine builder, he is a builder for a major racing engine development company, and does the labor and heavy thinking, and we share in the selection of components. I'm just an ol'e burned out street rodder.
Mesa,
Thanks for the tips on the lifter preperation. The lifters in the engine were off the shelf Competion Cams, but in all fairness there was no sign of a lifter failure. Our lifter bores were sized appropriately, however they will be checked again at teardown.
Strip,
Ultradyne is in business with a new owner.

Lmarth

Whiteknuckle-- Like a lot of us, I've been around the block a few times too. My problem is that I can't decide what I'm going to be when I grow up! My wife says I'm a perfect example of arrested development. Keep us posted on your rebuild. Lou