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Discussion Starter · #1 ·
I know Hydraulic Flat Tappet Lifter Failures are very common right now and was wondering if anyone has had a problem with the ones from Howards lately because I am just fixxin to break in a new motor.

And yes it is the lifters not the mechanics.
 

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Hopefully you lubed the lobes and lifter bases liberally with an EP grease made for this initial start. That you have a good initial adjustment preload on the valve train so things are initially functional at first start up.

Engine oil should be one of the break-in brands with an additional dose of ZDDP additive.

Fire up should be prompt on cranking so all the details of fuel delivery and ignition need to be checked as much as it takes to be positive it’s ready to fire up and you’re ready to stand by making initial running adjustments that keep it running for 20 minutes to half an hour at 2000 RPM.

This has the best chance of breaking a flat tappet cam in as opposed to just breaking it.

Bogie
 

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Race it, Don't rice it!
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FT cam falures aren't as common as the internet says. It jus those that do jump online to complain about while all the others are still out in the shop playing.
Follow all the protocols, it'll be fine.
Break in rockers are of 3:1 ratio are the way to go, Much less work than swapping springs in the car.
 

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Discussion Starter · #7 ·
Well I know 2 engine builders that have had hydr flat tappets in SBC chevies fail in less than 10 miles. These guys are pros and have been building engines for many mnay years and they are blaming the lifter quality. I'm just asking about howards in particular if anyone has seen a failure. Thanks.
 

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I’ve had several engines eat their lifters over the years mostly in the early years of building in the 70’s and 89’s. For serious builds I turned to including a thrust button on flat tappet cams to relieve the lobe and lifter from the added duties of thrust control in addition to lift from the lobe and follower. One should note that Ford has used a thrust plate on flat tappet engines forever and have never known had their engines known as lobe and lifter eaters.

The failure rate rose so high in the 70’s and 80’s that GM faced a class action suit. They won the suit but totally neutered flat tappet cams like the LO3/5 and institution of roller cams quickly followed.

Bogie
 

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Race it, Don't rice it!
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Well I know 2 engine builders that have had hydr flat tappets in SBC chevies fail in less than 10 miles. These guys are pros and have been building engines for many mnay years and they are blaming the lifter quality. I'm just asking about howards in particular if anyone has seen a failure. Thanks.
Alright, so poor quality is the blame. Address the problem area’s and the problem goes away right? Howard’s most likely has a few suppliers. Im pretty sure, Johnson Hylift is the only USA based manufacturer at the moment. Resurfacing your existing ones might be an option to look at.
Of the engine is already to go it’s a little late to worry about it now.
 

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I suggest Brad Penn oil. Its high zinc conventional and used by many racers and engine builders. Really have your **** together with dropping in a distributor and getting timing real close BEFORE firing up. I think many failures come from messing around not firing up cleanly and going to 2000 rpms . If you put in cam and used a degree wheel verify the timing tabs while at it. As a note,,,when the 2 dots line up on timing gear, that is NOT TDC of #1 ! It is TDC of #6...a reason why many mechanics try firing up 180* out. So cam gear dot straight up, crank gear mark straight up is #1 firing. Put cover on and line pointer up at about 12* BTD . Once you get the distributor in, rotate base till the points start to open or reluctor and points on shaft align.
Motor vehicle Crankset Automotive fuel system Automotive design Automotive tire

. this will get your timing correct to fire up without messing to much around. Another stupid mistake I see even veterans make is not having the carb filled up.If your using a mechanical fuel pump- take a squirt bottle ,,ketchup bottle ,,something and fill the carb through the top vent. Cranking over and over waiting for the mechanical pump to fill the carb is hard on a new cam! Just fill the carb through top. Also,,,make certain the lifters spin freely in lifter bores when putting them in with oil...if there's a little junk, or rust in a lifter bore...that lifter won't spin correctly and will wipe out that lobe in seconds. lower ratio rockers are good on BBC,,,but a sbc with hydraulic most time doesn't need them..unless you really got dual springs,,then removing the inners for break-in is best. Regular 1.250 springs with 110lbs, and 1.5 rockers is mild enough. Hope some tips helps,,,just be 100% sure it's ready to fire moment you turn key and straight o 2000rpms and vary 1800-2200 to vary the oil splash inside.
 

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riv87 mentioned a key point, ft lifters need to rotate, i would imagine this is quite often overlooked, any interference in the lifter bore or any other part of the valve train can certainly take a lifter out prematurely, a dab of paint on the pushrods and a couple engine revolutions before putting the covers on will tell you pretty quick if they are not moving,
Scotty
 

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If the valve spring pressure is ~300# per inch or less you're fine with regular oil -- AFTER BREAK-IN. As noted, for break-in you need to grease the lobes and lifters with an EP grease (I used to use Lubriplate... I think it's still made) AND a break-in oil or break-in additive. After the first 250-300 miles or so change the oil. I use a break-in oil or additive for that second change also, just to be sure. After that it depends on valve spring pressure. If ~3003/inch or less (basically stock valve springs) you're fine, but most high lift/high rpm cams recommend valve springs well over 300#/inch to better control valve float at high rpm. You can run lower pressure springs if you don't intend to wind it up, but then why have that kind of cam? Some like the "rumpty-rump" sound but just cruise around and would never race. If the valve start to float it shouldn't do any damage, you will just stop making power and will even lose some since the valves are no longer sealing, until the rpm drops below the float level (probably good to about 5000 rpm - most stock springs are - but depends on engine build and cam though). That "rumpty-rump" sound is a high rpm engine that runs very poorly and inefficiently at low rpm though. Most people just want the sound and don't understand that the engine is struggling to even run...
 
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To add...Cam lobe taper and Lifter face radius are VERY important. I feel like that's where a lot of problems happen. A close second are lifter bore indexing and spring rates. Mixing and matching cam brands with lifter brands might mean a different spec on taper and radius.
 

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Mike Jones at Jones Cam Designs sells these:
Lifter#: J842H
.842" Hydr F.T. lifter set
Price: $145.25

I don't know who makes them, but I know he sells only high quality parts. I thought they were made by Johnson Hylift, but their website shows only roller lifters. However, Crower 's website shows part numbers for several different versions of Johnson lifters for SBC. Maybe it's out of date.

**Edit: Just heard back from Johnson Hylift. They do not make flat tappets.

Also, my mistake on the comment I made about Crower. They only show 1 Johnson flat tappet part number, not several.
 

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Everything I run is either roller or overhead cam now. The only flat tappet I run in my mixed bag fleet is a Continental flathead which I suppose I will have to break-in again as the tappets were mixed up and subsequently polished. Springs are comparably weak in this engine so I hope it will be fine with just break in oil. Its a governed forklift.

Sorry, this post really belongs on Smokstak.
 
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