Are pushrods and springs really needed?

Craig@MFI · Jan 22, 2012

Wayne said:
Glad your stuff has survived on a wing and a prayer. It's a true testament to how strong stock stuff can be. Be careful on how you advertise your engine not blowing up for what you put it through. Next thing you know, people will be lined up at your door wanting you to buy them a new engine because they floated valves, and sucked one when you said they'd be fine. You are playing the "wait 'til it breaks" game to prove a point at how long it can survive. I played the "wait 'til it breaks" game before because I didn't want to cough up the money to do it right, and keep it reliable. I was not so lucky.

This is what happened to one of my 6.0's when I cheaped out on valve springs and push rods. FWIW the parts combo was an HT3B feeding an internally gated phat shaft 62 fueled by 190 cc injectors. It ran like a scalded dog until the valve hung open long enough to actually break, but then I got the opportunity to buy a completely new engine. (notice valve marks on the other pistons) I sure wish someone was there telling me to use common sense, and upgrade the valvetrain to RELIABLY match my power and pressure output. I count on my truck to get me to work, and cannot afford a failure due to neglect so you can count on me recommending to people in my situation (based on my own past experiences, and common sense) that supporting modifications are equally important to the mods that produce the most power per dollar.

Looks like it was just the exhaust valve.....would have loved to seen that back pressure....
Me, Eric at innovative, and Shawn Ellerton all ran stock springs and pushrods and never had a sinle issue in our 6.0s

I would never recommend a customer to not put them in but I also wouldn't tell them they need them when they dont

Craig@MFI · Jan 22, 2012

Dustball8504 said:
I agree! The added security is the only benefit in these things in the event that you would bend a stocker down the road. All it would take is a busted driveshaft to over rev one and let loose...

Don't that a few times on 900 hp passes and still fine broke two inputs and one intermediate

Craig@MFI · Jan 22, 2012

Erikclaw said:
I agree with the do it cause it is cheap insurance. Just cause one truck is torn down with no damage showing to the eye doesn't mean it isn't a good idea to replace them. The amt of money it is to rebuild one, I would spend the extra coin to lower the percentages of extra damage occurring if something let go.

Didn't your last motor fail because of a broke hd valvespring?

BFT · Jan 22, 2012

Why were the heads taken off in the place again?

Craig@MFI · Jan 22, 2012

Craig@MPD said:
Theres no damage to either...were just replacing headgaskets and putting bigger injectors and ii pump in
Just want to show people that springs and pushrods arent really needed unless going to a bigger cam or high rpm

Was said at the beginning....headgaskets...

BFT · Jan 22, 2012

So the gaskets were blown I take it?

Craig@MFI · Jan 23, 2012

Yes gaskets we're blown

Jeff@Spartan · Jan 23, 2012

75 psi of boost....I could see that happening. LOL

Wayne · Jan 23, 2012

Craig@MPD said:
Looks like it was just the exhaust valve.....would have loved to seen that back pressure.... the mechanical gauge read about 80 multiple times. all 32 valves touched the pistons enough to make impressions.
Me, Eric at innovative, and Shawn Ellerton all ran stock springs and pushrods and never had a sinle issue in our 6.0s

I would never recommend a customer to not put them in<<this I like! but I also wouldn't tell them they need them when they dont

Glad to hear it. I know as product developers, we sometimes do stupid things to our own trucks to prove how well stuff lasts. I know back when we were testing turbine wheel durability I ran my pyrometer up to 1800+ for more than 30 seconds at a time at least 2 dozen times, and beyond the gauges 2000* limit for sustained periods at least 6 times, expecting to melt the engine, but it's still running like a champ for the guy who now owns murphy. Would I do it on an engine I counted on? NO! would I expect it to live, or recommend to anyone to try it? Of course not.

My real concern here is that people might get the idea that running stock valvetrain while spraying nitrous, running larger injectors etc. is okay without a PROPERLY ADJUSTED wastegate is okay. never mind the high rpm's etc. I actually like seeing your truck's survival test as proof to the diesel community of just how much these engine's stock parts can take. Carry on:rockon:

Erikclaw · Jan 23, 2012

Craig@MPD said:
Didn't your last motor fail because of a broke hd valvespring?

No it did not fail from a hd valve spring failure. Too much bp for way too long with a stuck wg. Not sure what let go first but a lot did when it went. Piston stuck in cylinder, connecting rod tore out of the bottom. Had it inspected and it seemed like it was undamaged, even with it flopping around like it was still connected to the piston. Tough stuff.

lubeowner · Jan 23, 2012

The American Ride runs stock push rods, turns 5200 rpms and has upgraded valve springs. To date it has not had a single problem with a stock push rod. It did this with a large cam. The only real variable here is the truck runs pretty low back pressure. Also the with the large cam the piston tops were decked like 70 thousands.

Since it seems that things have changed with a certain vendor I think a more rational conversation can be had about this subject then a couple years ago with I last discussed this.

Yes Mike D, there were aftermarket push rods put in The American Ride's motor. I don't know who's they were. We never got that answer. The engine had a couple issues and it was found that a couple of these aftermarket push rods broke the little balls off the ends. So after digging them out I put in what I had and those were out of a 6.0.

Now on to how does a bent push rod cause engine damage? I don't know as I can't see how a push rod can. If it is straight it opens the valves like normal. It is bends it doesn't open the valves. I fail to see how a bent push rod and thus a none opening valve can cause a valve contact the piston. Valves contacting the pistons are caused by the valves not closing fast enough which has to do with either springs not being heavy enough for the given application, I.E. high back pressure or engine rpms. Or some outside impact causing the valve to stay open, like a debris, a piece of metal off some other mechanical failure.

Anyways, do whatever you like and makes you feel happy. That should really be all that matters.

WoodBoy · Jan 23, 2012

Erikclaw said:
No it did not fail from a hd valve spring failure. Too much bp for way too long with a stuck wg. Not sure what let go first but a lot did when it went. Piston stuck in cylinder, connecting rod tore out of the bottom. Had it inspected and it seemed like it was undamaged, even with it flopping around like it was still connected to the piston. Tough stuff.

Is that what they call a low compression piston?

BFT · Jan 23, 2012

lubeowner said:
The American Ride runs stock push rods, turns 5200 rpms and has upgraded valve springs. To date it has not had a single problem with a stock push rod. It did this with a large cam. The only real variable here is the truck runs pretty low back pressure. Also the with the large cam the piston tops were decked like 70 thousands.

Since it seems that things have changed with a certain vendor I think a more rational conversation can be had about this subject then a couple years ago with I last discussed this.

Yes Mike D, there were aftermarket push rods put in The American Ride's motor. I don't know who's they were. We never got that answer. The engine had a couple issues and it was found that a couple of these aftermarket push rods broke the little balls off the ends. So after digging them out I put in what I had and those were out of a 6.0.

Now on to how does a bent push rod cause engine damage? I don't know as I can't see how a push rod can. If it is straight it opens the valves like normal. It is bends it doesn't open the valves. I fail to see how a bent push rod and thus a none opening valve can cause a valve contact the piston. Valves contacting the pistons are caused by the valves not closing fast enough which has to do with either springs not being heavy enough for the given application, I.E. high back pressure or engine rpms. Or some outside impact causing the valve to stay open, like a debris, a piece of metal off some other mechanical failure.

Anyways, do whatever you like and makes you feel happy. That should really be all that matters.

Apparently you have never dropped a valve

lubeowner · Jan 23, 2012

BFT said:
Apparently you have never dropped a valve

And what causes a dropped valve?

BFT · Jan 23, 2012

Over revving for one, weak valve springs. A bent push rod can also cause this

Once you bend a push rod then the valve to piston clearance has been compromised.
Stock pushrods are good with stock valve springs. Putting in a stiffer valve spring is just overworking the push rod. There will most likely be some deflection, most likely harming performance

Craig@MFI · Jan 23, 2012

Erikclaw said:
No it did not fail from a hd valve spring failure. Too much bp for way too long with a stuck wg. Not sure what let go first but a lot did when it went. Piston stuck in cylinder, connecting rod tore out of the bottom. Had it inspected and it seemed like it was undamaged, even with it flopping around like it was still connected to the piston. Tough stuff.

looks like it in this pick

Craig@MFI · Jan 23, 2012

BFT said:
Over revving for one, weak valve springs. A bent push rod can also cause this

Once you bend a push rod then the valve to piston clearance has been compromised.
Stock pushrods are good with stock valve springs. Putting in a stiffer valve spring is just overworking the push rod. There will most likely be some deflection, most likely harming performance

ive been reved out to close to 5k rpms missing shifts and all still good

BFT · Jan 23, 2012

You didn't see the rid or piston, did you? I'm surprised the rod wasn't hosed, I looked brand new. The motor was running for a while so who knows what went on.