Another cam failure

[prairiehotrodder]

Helped a friend build a low buck 454 for a G-body Buick Regal. We used a Howards hyd flat tappet cam and Howards lifters. It was a mild .510 lift cam. We used comp valve springs that were close made for the same basic size of cam. We ran the engine on a test stand for half an hour with Rotella T 15W40 oil and the comp cams cam break-in additive. Everything seemed to go well. Oil pressure was good. Put the motor in the car a week ago. On the first evening my friend floored it a couple times and it started hammering really loud. It actually sounded more like a rod knock so we pulled the motor out of the car and found the very back exhaust lobe on cylinder number 8 was going away along with the lifter. Allthough these were cheap parts shouldn't they have lasted longer? What did i do wrong?
Brian

[raynorshine]

Helped a friend build a low buck 454 for a G-body Buick Regal. We used a Howards hyd flat tappet cam and Howards lifters. It was a mild .510 lift cam. We used comp valve springs that were close made for the same basic size of cam. We ran the engine on a test stand for half an hour with Rotella T 15W40 oil and the comp cams cam break-in additive. Everything seemed to go well. Oil pressure was good. Put the motor in the car a week ago. On the first evening my friend floored it a couple times and it started hammering really loud. It actually sounded more like a rod knock so we pulled the motor out of the car and found the very back exhaust lobe on cylinder number 8 was going away along with the lifter. Allthough these were cheap parts shouldn't they have lasted longer? What did i do wrong?
Brian

-you said low buck, and nobody loves low buck, no buck as much as me....but...here's the butt...you still need to check the basics...cheap parts will get the job started and go for awhile....but......shyt i said that again....

[superpursuit]

Helped a friend build a low buck 454 for a G-body Buick Regal. We used a Howards hyd flat tappet cam and Howards lifters. It was a mild .510 lift cam. We used comp valve springs that were close made for the same basic size of cam. We ran the engine on a test stand for half an hour with Rotella T 15W40 oil and the comp cams cam break-in additive. Everything seemed to go well. Oil pressure was good. Put the motor in the car a week ago. On the first evening my friend floored it a couple times and it started hammering really loud. It actually sounded more like a rod knock so we pulled the motor out of the car and found the very back exhaust lobe on cylinder number 8 was going away along with the lifter. Allthough these were cheap parts shouldn't they have lasted longer? What did i do wrong?
Brian

Here's a few things that can possibly cause this. Not using a molly based cam lube on the cam lobes and the bases of the lifters. [I don't like the CC red oil for this on flat tappet cams]. Too much spring pressure. Coil bind. Not enough travel between retainer to valve guide. Excessive cranking. [If the engine did not fire up immediately when starting]. [ Fuel & oil need to be primed, Ignition timing set, etc so that engine fires up immediately when the starter is engaged]. Not bringing the revs up to 2000 t0 2500 revs immediately when first started. Lack of oil pressure. Not running cam in for minimum of 20 minutes at 2 -2500 rpm as soon as it starts. Idling at any time in the first 20 minutes. Blipping the throttle during cam run in. [changes where the oil is being directed and causes "dry" Spots on the cam]. Overheating during cam run in. [Breaks down oil film strength]. Changing to a non ZDDP oil. Hard revs in the first few hours of operation. Setting the idle speed too low. [Not enough oil splash to the cam for it to live]. Plus more. Hopefully you can get an idea from this just what did go wrong.

[user-17438]

did you make sure all the lifters rotate at about the same speed? call me lucky but i use cheap oil for break in and havent yet had a ft problem. i also make sure i have adequate oiling, lifter spin, and thrust. maybe you got a soft lifter, or improper face. maybe it wasnt lashed properly. pics and better details please.

[EthylCat]

[quote="prairiehotrodder"]Helped a friend build a low buck 454 for a G-body Buick Regal. We used a Howards hyd flat tappet cam and Howards lifters. It was a mild .510 lift cam. We used comp valve springs that were close made for the same basic size of cam. We ran the engine on a test stand for half an hour with Rotella T 15W40 oil and the comp cams cam break-in additive. Everything seemed to go well. Oil pressure was good. Put the motor in the car a week ago. On the first evening my friend floored it a couple times and it started hammering really loud. It actually sounded more like a rod knock so we pulled the motor out of the car and found the very back exhaust lobe on cylinder number 8 was going away along with the lifter. Allthough these were cheap parts shouldn't they have lasted longer? What did i do wrong?
Brian[/quote]

I would get the block geometry checked/corrected while its torn down.

[BigBlocksOnTop2]

You know that wiping a cam requires a complete engine tear down. Starting from ground zero....removing oil galley plugs and brushing out clean. A complete cleaning is required. Look at the pistons, un stack the rings, do the skirts have tiny specks of cam/ lifter debris embedded. Probably and the pieces need to be removed (scrape each machining tool mark with a knife point and then use a piece of worn red scotch brite and scrub them good)....its a pain in the neck. Did the oil pump go into by-pass. If so the crank will be scuffed and may need a regrind. A lot to consider on a cam wipe. On the next go round use Brad/ Penn Break-In oil and cam/ lifter assembly lube on every lobe and every lifter face. CHECK for coil bind. Good luck....its a bummer, believe me!

[F-BIRD'88]

Put Moly Disulfide paste on the new cam lobes..

Reduce the spring pressure for break in.

I use this Moly based anti wear anti scuff oil additive in the oil to prevent premature cam wear.

You can get it there at Home Hardware , among other places.
http://www.molyslip.com MolySlip E Oil Supplement..

If you used Howards lifters with the Howards cam and have receipts they may (or may not)
warranty replace that.. You have to ask..

[427dart]

Could be a bad lifter that did not rotate in the lifter bore.
Answer me this... Back in the 60'sand 70's before hyd. rollers were the OEM engines all test run at 2000 RPM for 20 minutes before installed into new cars?
Or were all new cars coming off the line run the same for engine break in?
Only thing different here is what the quality of oil was at the time plus they most likely poured in an oil additive like the GM version. No time was spent swapping on weak valve springs on the High Performance engines.
So what is the mystery of todays flat tappet cam failures vs. how new performance cars of the 60's came off the line?
Yes I know some cars from the factory had some engine issues but we are talking millions of new cars.
Could it be the aggressive ramp speeds of todays flat tappet cams vs. the slow ramps of the early OEM?

[prairiehotrodder]

It got some hard revs in the first few hours. We used the Howards cam lube. Oil pressure was good. Hopefully my friend will spring for a hyd roller cam this time around. Do i need a timing chain with a torrungton bearing or can i re-use my current chain for a roller?
Brian

[F-BIRD'88]

Could be a bad lifter that did not rotate in the lifter bore.
Answer me this... Back in the 60'sand 70's before hyd. rollers were the OEM engines all test run at 2000 RPM for 20 minutes before installed into new cars?
Or were all new cars coming off the line run the same for engine break in?
Only thing different here is what the quality of oil was at the time plus they most likely poured in an oil additive like the GM version. No time was spent swapping on weak valve springs on the High Performance engines.
So what is the mystery of todays flat tappet cam failures vs. how new performance cars of the 60's came off the line?
Yes I know some cars from the factory had some engine issues but we are talking millions of new cars.
Could it be the aggressive ramp speeds of todays flat tappet cams vs. the slow ramps of the early OEM?

I believe the factory OEM GM engines were started and run on natural gas.
Yes the cam lobes were mild and the spring pressures on the stock bread and butter engines was quite mild. Mild spring pressure (EG: 60-80#seat--260ish# open)(low/moderate engine rpm limit) is better for initial cam lifter and rocker arm break in and extended life. But higher rpm range needs the increased spring pressure.
110-130 seat 300-350 open.
Yes the oil was of different formulation with plenty of zinc and some moly too.
The GM EOS is still very good stuff, too.
The MolySlip E is a good proven effective anti-wear anti scuff Oil additive.
You need a bit of this stuff when running elevated high perf spring pressures with high perf aggressive flat tappet cams, lifters and stock style rockers. It has both Moly and some Zinc in it too. Its good for the piston rings and cylinder walls etc too.
After the initial break in, I use just 1/2 the can in each oil change.
Once the engine is treated all you are doing is maintaining that small % amount Moly additive level in the oil.
More, beyond this is not better, ....so...

You want/need plenty of oil flow to the cam/lifter face and rockers to carry the Molyand Zinc to the surfaces and remove HEAT, during break in. Not rocket science that reduced mild(er) (OEM stock like) initial break in spring pressure is better to reduce the load on the moving parts to allow them to get friendly "break in" ...

[jeff swisher]

I read a few years ago the Comp additive was not any good.I have no experience with this additive though.

What RPM did you run it at on the stand?
Did you prime the engine before starting it?

Sucks when this happens.
I use Joe Gibbs BR oil now for all break-in.

As stated you could have got a bad lifter..I check the crown on all my lifters.
My cam guy told me a story about a 460 ford that wiped 3 cams and lifters in a row.. everything was checked and tripple checked.
I do not remember what cam and lifter brand.
But this was a friend of his and he refaced the lifters and gave them more crown and reground the cam with more taper on the lobes.
It did not wipe that cam.. and was still going strong over 10 years later.

I never thought of more taper and more crown being applied.. makes you think.

[F-BIRD'88]

You could check two (or more) of the un wiped out lifters together face to face to see if the crown face is still there.
If its not the cam lobe taper is suspect.
The lifters must spin in the bores when running. The lobe taper and the crown face is what makes them spin when running.
If the cam lobe taper is not still there (or never was) then that is a manufacturing error and is a valid warranty claim.
If the unknown Comp springs installed open spring pressure was all jacked up, thats another matter.
Flat tappet Cam lobes wipe out for a reason.

[prairiehotrodder]

the cam was howards 120051-10 231/231 .510/.510 110 and after checking invoices i see that it did have the matching suggested howards springs.

[F-BIRD'88]

Further you DO NOT want to use a cam button on a flat tappet cam. The flat tappet cam find its own for and aft sweet spot under the lifters. It is slightly offset under the lifters center. Do not force or restrict the cam for and aft in the block. Do NOT use a cam button nor a bearing behind the cam gear, on a flat tappet cam set.
The natural cam lobe for aft offset + the cam lobe taper+ the crown lifter face is what allows a flat tappet cam to run and not wear out even if when the lifter bores are not exactly 180 deg over the cam. It allows a slight angle error. and promotes lifter rotation and long service life.
DO NOT USE A cam button on a flat tappet cam/lifter.. They are for ROLLER cams only to prevent cam walk.

[F-BIRD'88]

What colour was the cam break in lube?

What was the valve spring part number.? I just noticed something odd in the Howards catalog re: the valve springs for that # cam.

Big block chevs are very critical on what the valve spring is. The valve train is big and heavy.
The wrong valve spring will allow valve float on a high perf cam and rpm over 5200rpm.
The listed spring #98515 for that cam # looks to me like a nice wimpy stock like break in spring but is going to get in trouble on a high perf cam beyond about 5200-5500rpm.

For decent valve control on that cam beyond about 5200rpm your going to need a spring like the OEM BBC LS-6 dual springs (125-330#) Howards spring # 98636 matches the job, to me.
(6000+/- ish rpm on a high perf hyd cam in a big block Chev)

To me it looks like if you got the wimpy #98515 Howards single springs and your friend did reved it up like you said, (6000+rpm) it may have valve crashed at high rpm with those wimpy springs. Thats enough to wipe a cam.
Check the springs # , open and seat installed pressure and installed heights. Big block chevys are more critical to get them right.
I have had to correct more than one BBC of friends etc, that had the WRONG valve springs for the job and would not perform (premature valve float with high perf hyd cams)

Like I said flat tappet cams fail for a reason. You do want a mild spring for initial cam break in but do not want a weak wimpy low pressure valve spring on a high perf BBC that you or your friend are going to rev it up... Big block Chevrolet valvetrain and valve springs are critical ... small blocks seem to get away with murder. The valve train is a lot lighter mass.

Some stuff to look at.
Your friend may still want to upgrade to a hyd roller cam but you can still investigate why this flat tappet cam failed.. They fail for a reason.