Flat Tappet Cam Failures: The Reason Why They Go Bad & The Solution! Part 1

Whoever manufacturers these need to have them return, right to their B hole.

One lifter went out on my sbc street truck. Trashed the cam, going retro roller.

You really think the chamfer matters? Considering that the lobe doesn’t contact the edge

You must change the oil and filter every 1,000 miles. Ignore the extended oil change intervals the manufacturer wants.

Çheck if pushrods are spinning and if they are your cam will be fine

oil oil oil, when engines started using roller cams the oil formulas were changed because they did not need the extra zinc and other things in the oil, the solution is to run diesel engine oil that still contains these additives, such as rotella 4 or some delvac. i found this out the hard way when my camshaft took a dive after a rebuild.

That was awesome brother thanks👍👍

I have an engine with 270,000 mi and the cam and the flat lifters work. So its not that they are flat.

In the last year or so, Comp has started a Nitriding program for their flat tappet cams and I had my last SBC XE-274 cam done. It had a good 500 mile breakin period and I also used BREAK IN ROCKERS that were just 1.3 ratio from Speedway. After the breakin, I switched out the breakin rockers for normal 1.5 ratios on a 400 SBC and it has worked out very well. I brought that motor up to 2000 rpms immediately and varied it up and down for the first 20 minutes while I checked for leaks and let the motor get warmed up. It has over 5000 miles on it in a old 1986 Z28 and so far, that procedure has saved any failure. I do still use Castrols Hot Rod Car oil that has added ZDDP in it and during initial breakin (and the 2nd oil change also) I used Lucas Breakin 30 wt oil WITH additional Rislone ZDDP additive. Less spring pressure with the 1.3 rockers was definitely a good and easy thing to do to keep from flattening a new cam. Just my 2 cents and I've been building engines for over 45 years. Thanks for the interesting video. Very informative.

As I have mentioned before, I don't work on engines anymore but I really enjoy your videos. I am AMAZED at how many engine folks DONT understand the basics. They will spend 1000's on parts and dont understand the basics of oil, lubrication, zinc, etc. And like that you mention the Penn grade oil Driven has...its all I used in my 66 Mustang. Keep up the good work !

Very good info. THANK YOU.

Cause it's in a Chrysler product.

42 min video to explain how to overcome cheap parts! Damn shame even the US manufacturers aren't much better than the Chinesium from FleeBay.

Det där är nog ett modärnt problem mycket mer sällsynt på 60,70,80 talet beror nog på sämre skitlyftare på 70, 80 talet använde jag Sig Erson å funkade bra på den tiden, men har råkat ut för piratcammar till IH som inte roterade med förstörda lyftare å cam

Just stop putting rock hard springs on them. I blame most of the failures on hard springs. So what if it floats at 5500, At least it keeps running for years. Soft springs save engines and give you a built in limiter.

The gas today has no lead in it today's oil has no phosphorus in it is what's causing that use Brad penn green oil take RPMs up to 2000 for 20 minutes and Break cam in properly change oil look for metal if good you're broke in and it'll run fine

Makes sense 👍

You made no reference to the lifters Comp and Isky sells with the holes in the bottom. We had used the Iskys on an Isky cam and the Comps on a Comp cam with no failures. The are not the same, I expect that to be a trade mark or patent thing but do you feel the are an advantage. Would the comp coating be an advantage on theres. Thanks

Setting Correct Rocker Arm and valvespring lash is critical alongside using the correct length pushrod and correct springs for your application.

I remember when you could buy a stock 350 Melling cam and lifter set for under $100 USD in the 90s.
INSANE to think you can get away with not using break in oil on a new or rebuilt motor. Same with using moly lube on the cam and lifters. I applied it to the rockers and valve tips. Also any wear surface that doesn't have direct oil feed.
You can check the RC on a used cam. The lobes that are not damaged are going to be the same or near factory hardness. Yes that machinist did intentionally show the harness of the wiped lobes were lower due to friction heat.
IMO 90% of the failures are improper lube, Preload adjustment, RPM, VS pressures, and time before putting a major load on the engine.

The oil these days doesn’t work good for flat tappet…EPA . They radius on the bottom they try to turn on a CNC lathe . It needs to be ground with not to smooth a finish and not to rough. To smooth they don’t spin I’d say a 32 RMS finish
That’s my take as a machinist of 40 years

You have convinced yourself that Zinc additives are the answer, when "running in". On street vehicles, 40 years ago we just used straight (cheap no additive) oil for 1000 miles. Then we dumped the oil and refilled with your good oil. Part of the problem with running in is the driver of the vehicle. Generally you should drive around at local speeds, varying revs and load as you go. Add a few hills into the mix to vary the load on the engine components. You won't get a good result off a bench. As for the cams, a good coat of Moly was all we used.

Thank you for explaining everything. I'm in the middle of building a small block Chevy and I have been worried about if my cam would survive the break in. Now I know what I need to do. Thank you

I have seen lots of roller failures in factory engines. A couple were in my own well maintained vehicles. I hope the aftermarket performance folks are doing a better job than OEM.

Good way to sell expensive lifters and cams. hmm

Get back in the mid-90s the dirt tracks I ran you used to be able to run roller stuff 3 years ago they started making us run the flat tappet cam stuff I've had two motors with the flat cam and lifters and my engine builder must know what he's doing cuz I didn't have a problem with either one of the motors he's built for thank god but it was nice to see this video on what would cause it or could cause but thanks for putting out the video buddy appreciate

I now have 2 comp cams hydraulic flat cams for 2 of my 350 Chevy motors for both my Camaro sports cars. I run good oil with zinc additive and change the oil regularly. Haven’t had a problem with comp.

Just a fyi...comp cams owns crane cams and lunati...all them parts come out of the same house....

Would be great if the manufacturer supplied broke in cam lifter kit with matching springs and other components.

I feel the best way to cure these cam/Lifter issues of Hyd flat tappet cams is find a motor builder person that has NOT been having any issues!. I been building flat tappet motors for many decades and never had a cam problem, a not 1. One thing I see over & over is guys not useing enough of the black molly high zinc grease on their cam or lifters when building the motor. The cam companies only give you 1 very small packet of the grease, ( that is NOT enough !) and many guys only use assembly lube, or fail to apply the black molly grease correctly. I always buy a extra pint can of that high zinc molly grease (Isky is good) and coat everything ( all the cam and the faces of each lifter really heavy. I also do my standard 30 min brake in at 2,100rpm with QTs of straight weight 30W Lucus high zinc brake in oil, (having problems getting Driven in Florida) drain it hot after 30 mins, replace the oil filter & refill with more 30W brake in oil drive the car 100 miles easy moving RPM up and down all the time. then drain the oil again with another new filter and more 30W brake in oil for a 3ed time, and again drive the car easy moving RPM up & down always under 3,500 rpm for another 300 to 400 miles and change the oil & filter again and continue to run 30W brake in oil for the first 2,000 miles changing the oil& filter every 500 miles. After 3,000 to 4,000 miles more, I switch over to straight weight 30W high zinc Valvoline VR-1 racing oil (there are better oils, but best I can find in this State right now)

The real reason is they are made in China!!!! Nothing is made in the US !!!! It’s all rebranded!!!!FTW

You are concerned about the lifter bores but the cylinder bores look terrible

This is the best information I have seen on this subject, thank you.

Why criticize others explanation for failures without stating why there has been a rash of recent failures for people following all the proper protocols

So this is your opinion and your promoting an oil

So how do we know your right and the other guy wrong.

Parkerizing the flat tappet lifter surface and cam lobes etches the metal to hold oil during cam break-in

I just built a 402 for my daughter's '69 SS el Camino and I used the Crower "Baja Beast" cam that came out of the old motor. I put Elgin lifters in with it. Haven't started it yet. Would I be better off with a set of Crower "Cam Saver" lifters? How about those DLC coated lifters?

only gas engines are having this murder cam problem - diesel engine rebuild world is not having this problem - overseas steel market not USA regulated. My guess is these lifter manufacturers are getting inferior steel from over seas.

The source steel is made over seas - the final machining/grinding is done in America. So mace in America is only half right. Furthermore, made in America only has to be above 50% in many cases.

Let me tell you man I really thank you so much you just save me a lot of money because I am up to this part but believe it or not and tomorrow I am going into my garage checking if I bought the cam from Summit and if I got the list is from Summit as well And hope that there are the matching set for that cam and as far as the springs like the ones you just showed I am using on my heads I have a 350 small block for boat main and don’t know the pressure on those and never even thought that I needed to know thatso I will be bothering Summit tomorrow to get me springs as well to match the lifters and the cam. Thank you so much. Also, I am buying that oil as well priming oil.👍👍💪💪💪

This is why I don't use flat tappet cams any more to much BS involved

There are not very many lifter manufacturers in the world most cam suppliers are reboxing lifters you will hear people say Oh it's Chinese junk that's not the case. The problem is 2-fold the first is low ZDDP in the oil not using the correct oil can wipe out a cam along with the improper break in procedure the other problem is the machining of the face of the lifter not being machined correctly. Rotella does not have much ZDDP these days zinc additive does not work with detergent based oil you half to use non det oil if you use additive the best bet is to use Driven or Lucas Break in oil I have personally stopped using flat tappets altogether everything you said in this video is correct I put out a video last year from my shop and basically said the same thing you did here we have a cam grinder and a lifter face grinder there are so many bad lifters being sold from every cam supplier we have reground thousands of lifters out of the box form every major cam supplier in North America and I can tell you every single one of them is selling lifters with little or even no crown at all, you really need to chuck a lifter up in the machine to know if the crown is correct or not I can tell you most lifters being sold across the board are junk Howards actually has the best flat tappets but even they had some bad ones like I said been machining for 35 years and I am done with Flat tappets good video

Very very very helpful thank you.

Just now after realizing things, watched your explanation earlier today 11-20-23, I'm takin the HIT, going roller on my AMC 401. NOT takin a chance.
I've listened to and watched too many Good guys I trust and it's a sobering moment of "revelation" .
The message in the scenario is do it twice with a FT and extra costs or once with a roller and carry on!

Either way I'm looking at the near same $$$.
Just with a roller, NO need to pull engine twice and no down time for 3 more months!
I'm hearing it in your voice and The other guys voices too.
There is a time to realize wisdom when it's facing you and THIS I believe in all my automotive decades experience is One of them! - Go Roller.

I just lost a cam after break-in and a test drive,never lost one before. I'll give it one more try before doing a retro roller.

Captin Obvious here with the solution. Whats happening to the lifters and cam during the break-in of an engine?
Your "heat treating" or "seasoning" them.
Just as one would do a heat treatment on a knife or a new cast iron cooking pan before useing it
There is lots of you tube videos that explain the process in great detail.
heat treat the face of the lifters in a frying pan and put the cam in the oven.
Pick the heating and cooling temperatures that the engine would reach during the breakin period.

So over time oil has changed, windage trays and main girdles are more common, high lift cams with possible ramp rates changing spring higher pressures are more common than back in the day. Along with possible mix matched cams and lifter crown and tapper. Break in procedures.
Sounds like any one of these could be enough to take out en engine.

Comp sucks period I would not anything from them. Nothing