Okay... I have about 700 miles on an engine freshening... 97", app. 10:1 compression, ported heads, big valves, 585 cams.

Over the last 100 miles or so, I've started thinking that my valvetrain was getting louder and louder (and I did install Rockout bushings while it was apart). I decided to try just a little bit more preload in the pushrods. I had originally set them at .135, and I decided to try .145. I ran the engine for about a minute to make sure the lifters were fully pumped, found TDC, verified the lifters were on the base circle, and took all the load off the pushrods. Then I snugged them up by hand, and counted the right number of flats for .145 (I checked my math twice). I waited to make sure the lifters bled down, checked that I could turn the rods by hand, and put everything back together. The engine really didn't want to start at all. It finally started, idled for a couple of seconds, and quit. I did everything again, thinking I must have made a mistake somewhere. Tried starting, got one big smokey cough out of the carb, and nothing else.

What did I mess up? Could I have too much preload now? Should I actually try going the other way, maybe down to .125?

Also, now that it doesn't want to run, how do I know that the lifters aren't bled down already when I start adjusting?

I'm super frustrated right now!!!

 

The lifters should have springs inside that keep them from collapsing in a no-load (or light load) situation. Take the pushrods out and let it sit for a couple hours to let the pistons pop back up.

As for preload, not sure. I'd contact both S&S and your head builder to see what is expected.

Did it sound "chuffy" when cranking last time? Like air passing thru a cracked valve. That's how it sounds with too much preload (or bad cam timing).

Not sure if you have compression releases, but it wouldn't hurt to check them if you do.

I hate hydraulic lash adjusters.

 

My twin cam has S&s premium lifters they say to adjust to 4 turns which equals 24 flats ( 6 flats is one turn) that would put u at 128. I went 4.5 turns which puts me at 144. I do have 1.9 intakes with high lift springs and I do get some valve train harmonics. I also did the rock outs . Runs like a bat out of hell. My Evo also has S&s lifters set at 4 turns. Are u sure u were on base circle. S&s says to wait 20 min for bleed. I would do a compression test . Good luck

 

One turn or 6 flats equal 32 thou

 

^^^^ This

@ .125 - 130

You need to make sure you are on the flat of the cam, and then regardless of time... don't adjust anything till you can easily rotate the lift rod by hand.

 

Okay... Set it at .125 and it fired right up instantly. And it seems quieter too... Chris, yes it was kind of "chuffy..." Perfect word for what I was hearing. Thanks for everyone's input!

Just an aside: My pushrods are 24 tpi, and only 4 flats (not six). So for me, one flat equals equals .0104. 12 flats equals .125. I have no idea what brand they are...

Sorry for my dramatic plea... I've had a very short fuse lately. We're down a manager at work, and I haven't gotten home before 10pm for the last two weeks (except Sundays). I'm planning on hitting the road for two nights over Labor Day, and this was my only day to make sure everything is running right...

I think all is well, I'm just heading out for a ride to make sure.

Thanks again!

 

When I read contact S&s I just assumed we were talking S&s .

 

I do have new S&S cams, lifters, cam plate, oil pump, and pistons... But my pushrods seemed completely serviceable so I didn't replace them.

Just rode 45 miles, and all seems fine now! Thanks again!

 

Good to hear! Enjoy your labor day ride!

 

Glad it worked out!