T/D shaft rocker life span
 

Was talking to a friend today that I consider a valve train expert (RMBUILDER) and we were discussing the life cycle of various motor parts used in high performance motors. I am running T/D Aluminum shaft rockers, running 180-190 psi seat and 490 open pressure. RMbuilder is of the opinion after a lengthy conversation with T/D that they consider the life span of the rockers to be about 17,000,000 cycles which is only about 80-100 hours, I currently have 120 hours on my 540 (including dyno time when I put it together last time) and am getting ready to freshen it.
I am looking for input from other engine builders/members as to how long they typically run these rockers before having failure or replacing them as good measure. I obviously don't want to have a valve train failure but on the other hand I don't want to spend 1500$ on another set IF the chance of them failing in the next 100 hours is very slim. I would run them another 100-120 hours IF I re-installed them most likely as I typically never have motor apart in the boat, once it comes off dyno I make sure its sealed up and I run it. These have seen 6200 rpm's if that makes much difference and I run up to 14 psi of boost but like most boats the majority of there life has been at 3500 rpms or so, thanks in advance for your input, Smitty

Might be why Crower, Jesel and T&D offer stainless.

I was just talking to someone about this on Monday. He pulled 2or3 broken T&D aluminum rockers out of his tool box that he had accumulated over the years. He said that he just talked with Bob Teague about this issue. Teague said that he uses the stainless now. He ended up buying a new set of stainless shaft mounts from him for his Dart heads. And the pricing was the lowest he has seen.

I used to run the aluminum t&d shaft rockers and have 2 old broken ones in my toolbox lol, I recently purchased the steel shaft rocker systems from them and I'm hoping that will solve the problem. also my old aluminum rockers were on the individual stands and the new steel ones are the 1 piece intake stands and the exhaust stands bolt to the intake stand, and for added strength i welded the exhaust stands to the intake side so i basically have 1 big stand that everything bolts up to. Should be much more reliable and way stronger all around

T&D will inspect and rebuild your rockers pretty affordably. Good customer service.

I can't comment on the T&D rockers since I typically use Jesel. No particular reason other than I use their belt drives it made it easy to order rockers from them to. With that being said, I have run the Jesel Sportsman Series rockers for well over 300 hours without issue. I just freshened up a pr of my 1350's in that 399 Skater Vee. They have a total of about 230 hours on them. SPring pressure is 175 on the seat and 550 open. We turn it to 6500 rpm occasionally. They have had a pretty rough life as I have run it at the Shootout the last 2 years, plus the owner is pretty hard on it.

I have another set that have well over 300 hours. It's a pair of 598 with 3.3 Whipple. Springs are 165 on the seat and 430 open. They spin about 5700 rpm. I just freshened them up and all the rockers checked out fine. I put them all back on for another 300 hours hopefully.

I can't imagine that there is that much difference between Jesel and T&D. I would think you should be fine. Might be worth having a look at them though. Give them all a spin to be sure the trunion and tip roll smoothly.
Eddie

Smitty, Send them to T&D and have them inspected. I had one break last year at the end of the season so I sent both sets back and had them checked. They found one more that was out of spec (junk) and replaced a few bearings. Not much time on these so not sure why two of them were bad so we will see what happens this year with the rest of them. T&D assured me that I would have no problems but we will see what happens. Good luck, Rob

Are the "steel" shaft mount rocker arms from T&D actually "stainless steel"???

If the T&D aluminum roller rocker arms are only good to roughly 17,000,000 cycles, then how many cycles are the steel or stainless steel ones good for?

I think I have either heard or read that these steel (or stainless steel) rocker arms from T&D are actually lighter than their best/lightest aluminum rocker...???

Actually, I am interested in purchasing T&D's shaft mount system with their integrated spring oiling system---perhaps it might be getter to purchase their steel/stainless steel shaft mount rockers vs their aluminum ones---yeah?

Can anyone please shed more light on this. Thanx in advance

Just curious, has anyone ever seen or heard of a broken Crower stainless steel rocker ?

Kaama,
I went with the aluminum ones because I'm not running real high lift or high rpm and was looking for ways to trim the budget. I cant remember how much more the stainless was than the aluminum but it wasnt double or anything that bad. Rmbuider said that the stainless other than being stronger also stabilized the pushrod motion or something to that effect. The spring oiler option is a great value at several dollars per lifter. I just figured in my engines that I wouldnt need them. Rm is definitely a fan of them.

When I bought them I wasn't aware that they made a steel one that had a infinite life span and that the aluminum ones had a fairly short lifespan , if I had I would have spent the xtra dough!!!

I wonder if they magnaflux them or what? I will either run them another 100 hours or sell them while still perfect and buy new steel ones.

Buy the steel, pay extra for spring oilers and never worry again!

I spoke with Bob Madara for a brief moment today...
 

Yeah Steve! I'm sure thinkin' about it! I certainly don't need to have the thought of fatiguing aluminum rocker arms constantly running thru my mind. I guess I'll just have lay down a little bit more of that SMACK...$$$ :popcorn:

You need to tell Bob that you need some cams for them motors that will idle at 500 rpm's glass smooth and pull to 6500 making 1300 hp, have him figure out ten different grinds for you from mild to less mild, I am sure he could do it for you:evilb:

I don't know how long ago you bought yours they may not have had steel at that time. I believe Crower was the first to have stainless shaft rockers and it's only been a few years.

The T&D steel rockers were available at the end of 2006.

You know Steve, I am propbably one of Bob's worst nighmare customers...the only customer who wants a smooth idle. I'm sure when Bob's phone rings and he looks at his caller ID and cringing while knowing it's me on the other end----I am quite confident this is Bob's reaction while he's stares at the ringing phone knowing full well he has no recourse but to take my call---> :picard1:

but he braves the challenge, takes a deep breath and takes my call with his professional voice by always saying---"Hey Mark, how are ya?"---almost as if he hasn't spoken to me in 3 days! ha :eek:

He's a very knowledgable guy, but I must admit, if there is one thing he knows I hate---(which sounds like a chainsaw on steroids), is that he seems to enjoy rattling my cage with ending our phone conversation by mimicking the idle charactoristics of the boat called "SORCERER" ....as he is hanging up the phone on me. :party-smiley-004:

Didn't know that, I guess they knew they had a problem in some applications.

I bought mine in early 06 if I remember correctly, when I buy them again I will definately buy steel!

Update to my earlier post. I had two sets inspected and freshened at T&D only to have two more break within 3 hours of run time. I was assured by T&D prior to sending them that they would not be a problem after they worked on them. Now they tell me that they cannot guarantee anything as they do not check them for cracks only replace any parts that they deem worn. Not very pleased with their customer service as I would never had them reworked if I hadn't been assured several times by T&D that they would be good to go. (I was led to believe that this was an uncommon problem but this past weekend I was talking to another boater that experienced the same type of breaking problems with T&D rockers) Now T&D tells me they want $3200 for 2 sets of steel replacement arms or they might be able to use some of my parts from my originals and that will cost me only $2400 or so but won't know until they inspect my original parts. Doesn't sound like much of a deal to me! Did a little research and I think I can get Crower S-Steel arms machined to fit my current stands for $800 per set. Just an FYI for anyone contemplating using T&D so you don't make the same mistake that I did!

I sorta thought that when having them "inspected" was mentioned, if they are fatigued but show no signs of distress or cracks then all that could be done would be to change the tips and hardware. I bought new steel t/d ones, are the crower ones you mention that drop onto the t/d stands 800$ a full set or just 8 exhaust? I think even with re-using my shafts it cost me more than that for just 8 exhaust from TD in steel, Smitty

Sometimes metal fatigue is hard to detect without an X-Ray. I've seen mild steel shatter like glass in stamping presses from the constant pounding. I was thinking about switching to aluminum rockers before I did my homework. I'm sticking with my Pro Magnums, they seem to have the best reputation in the less than stratosphere priced components.

Price is for a full set(16) stainless rockers minus shafts as I can reuse my shafts (same diameter). T&D seems to think pretty highly of their parts and prices them accordingly as they want $1120 for 16 empty bodies and then I use everything from my existing rockers except the the body! Not so sure I feel the same as they do when I can buy S-Steel for about $400.00 less per set with all new parts included . Kinda hard to justify their parts.

don't think you can magnaflux aluminum since it uses a "magnet"

I would like to know more about the Crower units on the T&D mounts.

Just broke one this weekend at Cumberland Poker Run, 1075"s with about 220 hours on them.

Not overly impressed as I started having problems last year and after several hundred dollars and reassurance several times from T&D ( prior to getting my money) I am still having breakage issues. Fortunately it is my own personal engines and not a customers! This will quite possibly be my last set of T&D products as I would never feel comfortable using these for a customer after these issues and it seems that their steel ones are gold impregnated based on the price!

KVOGT, feel free to call me about this and I will put you in touch with the guy you need to talk to about possible Crower replacements. My cell is 989-464-5531. Rob

RB when did it break? I wondered where you went Saturday.

I just removed a failed SS crowler rocker from my 572 nat asp last weekend.It broke around the bottom of the pivot area and all the rollers fell and broke out.I do not know any history of this motor rpms or hours so I will probably go back with them again .I am considering jesel stuff.Motor's apart now for a refresh. hf... I got pics if anybody wants em. sho miss my boat when it's broke

Please send detailed pics to [email protected] I would like to see the break area and get some input from my guy at Crower before I make the move to their s-steel rockers. Are they shaft mount and do you know approx how old it is? Thanks, Rob

Rob, at first glance the crower stainless rockers (IF they actually make a drop in replacement) sound like a bargain BUT keep in mind the weight difference between profiled t/ds made from Chrome moly vs the 17-4ph stainless Crowers, My new steel T/D exhaust rockers looked like skeletons-definately profiled to be extremely light. IF your valve train is spec'd out to exactly the rpm's you are running and you add 30+ grams of weight to control a valve spring change might be in order and will kill any savings you might have . Example-you designed valve train with lets say 250 seat and 600 opened pressure and everything is stabil to 6600 and you set rev limiter to 6500 if you throw in some extra weight you could see loss of valve control. Now, if you put springs in that were way over kill it would be a moot point, let us know what you do. I swapped out my Exhaust rockers at 105 hours or so (I figured 11 milion cycles or so), I mighta been able to run them much longer but didn't want to chance it , I would give them to you minus the shafts (I re-used them) if it would help get you back on water for rest of the season, Smitty

Sent ya the pics catman01. hf...

Smitty, Thanks for the offer of the rockers but I still have a couple spares left and doubt that I will get out boating anymore this season. The Crowers can be fitted in the T&D stands by machining the sides of the Crower rockers which they have offered to do and that is included in the price that I posted. Rocker weight becomes more of a concern the higher you spin the engine. The moment of inertia is probably the most important thing to consider and at the RPM's that these engines turn (6300) I doubt that these will cause any problems as I believe that the moment of inertia is similar. Feel free to give me your thoughts on this. Rob

halffast, just looked at the pics and I will forward them on and let you know what I get for an answer. Thanks for sending them, Rob

We pick up our last card at Wolf Creek Marina and headed to Harmon Creek and one broke.....limped back to State Dock and began drinking. ...not a bad day...ran great up to that point. Got it back together tonight...all well.

Crower also offers a chrome moly replacement that can be fitted. Anyone else have T&D that would like to share their experience?

With my refresh I got some decisions to make.I had a solid lifter roller cam.Should I give up a little hp and go hyd roller ? Is there better valve and top end life going this route ? Never had these problems with two big ole mercury race outboards on da back !! hf...