Reply With QuoteYour makin me nervous. Just broke in my cam today, but will be exchanging stock intake for blower intake tomorrow. Will take a good look at the lobes.
Well It appears the the Cam got wiped out! How I can't say for sure at this time. #8 exhaust rocker isn't moving very much...I did all the normal precautions required for a hyd. flat tappet cam break in...and then some. I'll be checking spring pressure tomorrow.(there may be something fishy there). The heads where only thing that was sent to the machine shop. I only ran the motor up to 3000 rpm.
Something I thought of...my original spring set-up only had 1 spring w/ the dampner...when I got the heads back this time...my machine shop added double spring ( a smaller inside one)...I asked him why and if it would pose a breakin issue with the new cam...He stated that no it would not, and he added the second spring so he wouldnt have to shim-up the single spring set-up, and also the seat pressure is about the same as before....BUT what I'm thinking is what if the spring (RATE) increased significantly as the lifter climbed up the lobe? Could it have been just enough to cause a broblem? Still waiting for a friend to come over with a spring tester so we can check it out on the motor...and if there's an issue with what he did...well I guess he'll be ponying up for a new cam and lifters!
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I pulled the Intake off and low and behold...the #8 Cam lobe and lifter are in fact wiped out big time, I mean the Cam lobe looks like a rolled over nub! And the bottom of the lifter is concave just over a 1/16" with a very small chip missing from one edge.
So do I belive that the oil filter did its job and took care of any Crank and Bearing damaging debris???? When draining the oil there where (no) metal flakes or chips...but more like a silver type of dust mixed in the oil. Also no metal flake's where to be found in the heads where oil puddles. Oil pressure was solid...hate like hell to yank that motor out after just installing it! Some tell me to put another Cam in and do a run and flush with clean oil and filter several times. Tough call on this one!
[This message has been edited by HammerDown (edited May 12, 2002).]
Your makin me nervous. Just broke in my cam today, but will be exchanging stock intake for blower intake tomorrow. Will take a good look at the lobes.
I feel for you, been there and done that. IMHO-the only thing to do is tear it down and clean/check everything. Mine was a Competition Cam and they replaced it under warranty even though it was not their fault.
JB
I lost a cam before but since I have the filter bypass plugged, it all stayed in the filter but, the garbage also chewed up the pump a bit on the way to the filter...Just my experience!.......
Deez, here's a tip!. Take your filter off and cut it open, that tells all. It should be clean, if there's garbage in it, something's going away..... http://free.***boat.net/ubb/eek.gif
Bummer. If you don't yank the motor now and thuroughly clean it out (hot tank, soap and water, blow dry), You'll be REALLY pissed if you loose a bearing after replacing just the cam and lifters because now you will have to add machine shop COST and TIME to the fix. Not to mention the wasted time you you just spent replacing the cam and another hassel on the water. Not worth it to me.
How'd you break in the cam?
The cam lobes only source of lube is from the oil flying off the crankshaft. That's why it's IMPERATIVE that the engine be run between 1500 and 2000 rpm's for 20 min's during break in. If it idles during this period you are likely to wipe the cam.
yep, when I tore my motor apart, the cam bearing was bad, but the cam was perfect. If you don't put the cam lube on it or keep it at a high idle for at least 20 min, bye bye cam. That is why it is so important to make sure it runs before you break it in becuase if you are running it and it keeps dying or whatever, the cam will never break in right.
H D, Shockwave, is right pull the motor down. You have to clean it.Drag a magnet through the oil if that silver dust sticks to it maybe you have other problems Who put the cam in and what did they lube it with. Check the push rod and rocker arm for strate. Was the motor back fireing during the break in time.
One of many good reasons to pony up the money up front and run a roller cam.
Well lets see where do I begin...To answer a couple quick question's above...
Yes I installed the cam and took every precaution and then some when doing it. I've done this before with never a mishap.
Yes the motor fired right up, and I took it to 1800-2200 rpm for aprox 20 min. dumped the oil and saw some silver dust in it...thought it may just normal break in junk...not so.
Now what I've come to find is that my machine shop add'ed a second inner spring to my original single spring set up.
What this did was to increase not only my installed seat pressure but also drove the open valve sprind psi ski high!
The cam never had a chance, the only thing it could do was burn up.
My original spring# is 911-16 a single spring w/dampner. Aprox. installed ht. at 1.900 should be 115 lbs....with the extra spring he added it went to almost 140lbs.!!!
The Open pressure of the original spring was almost 285 at 1.500...with the added spring it tested to be 370 lbs.!!!
When I picked up the heads from the shop some 2 months ago I noticed the added spring. I asked him if there would be issues with Cam break in...he assured me no way.He stated I added the extra spring due to comp. Cams up grading the required spring to part#924 which is a double spring w/dampner
BUT...here's the factor...my single spring was beefer than the big spring on the double set...get what I'm saying here? He totaly over chargeg my spring setup.My single spring was almost as strong as a double spring...and he add'ed another inner spring! And also Comp. requires the builder to (((remove))) the inner spring on any double spring flat tappet cam for break in.
The moral of this experance....I'm ****ED! even though I proved he messed up using his own spring tester in front of him...He just dosent seem to care.
I do agree the motor must be torn down...and a real shame after all the work I've done on it and money spent...over 450.00 on the heads alone. And only ran it for maybe 30 mim total.
But not going thru it and checking everything out again would be to nerve racking being out there on the water and not knowing it may blow at any time. There's no fun in that!....so....here I go again.
Much thanks for everyone's input on the matter....HammerDown
[This message has been edited by HammerDown (edited May 13, 2002).]
Hammer, that's a real bummer of a situation, but tearing it down is the right decision. Hopefully there won't be any other damage.
Just be glad you have an engine, mine is STILL at the machine shop...... but should be home soon.
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