An alternative to cadillac

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miata
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An alternative to cadillac

Post by miata »

Has anyone else had rocker shaft failures while using the cad500 solid set?

I have 8 broken ones, replaced by, 8 brand new ones..... with cracks. All the cracks are in the drilled holes.

Anyone else seen this?

Is there a better alternative?

twin engines, these are workhorses. 3k rpm, full load for about 45 minutes at a time.
Last edited by miata on Tue Jun 15, 2021 1:49 pm, edited 1 time in total.
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kwanjangnihm
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Re: cadd500 broken rocker shafts?

Post by kwanjangnihm »

miata wrote:
Mon Jun 07, 2021 7:34 am
twin engines, these are workhorses. 3k rpm, full load for about 45 minutes at a time.
miata can you explain how these twin engines are being utilized?
He'll cut your throat, baby, stick you in the back, drive off in your Cadillac.
He's more trouble than you think, he'll kill your sugar, leave you in the drink.
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Re: cadd500 broken rocker shafts?

Post by miata »

kwanjangnihm wrote:
Mon Jun 07, 2021 9:48 am
miata wrote:
Mon Jun 07, 2021 7:34 am
twin engines, these are workhorses. 3k rpm, full load for about 45 minutes at a time.
miata can you explain how these twin engines are being utilized?
absolutely.

High-speed wind testing

I use 2 of these 500's to blow through a flow straightener, creating what is basically an outdoor wind tunnel.

Direct drive

each swings a 76" WW 2 blade whisper tip

full rebuild on both, used the cadd500 kit with the ( .625" cam ?) ill check that number again.

each test is about 40 minutes of full load @3k rpm

All weather conditions, freezing rain to 110°F summers.


ultimately I need 4 engines and it probably wont be 500s. looking at just an LS base package with a big cam, but open to suggestions.
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Deano
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Re: cadd500 broken rocker shafts?

Post by Deano »

miata wrote:
Mon Jun 07, 2021 7:34 am
Has anyone else had rocker shaft failures while using the cad500 solid set?
I have 8 broken ones, replaced by, 8 brand new ones..... with cracks. All the cracks are in the drilled holes.
Anyone else seen this?
Is there a better alternative?
twin engines, these are workhorses. 3k rpm, full load for about 45 minutes at a time.
No, this is not a typical occurrence. Shaft rockers should've solved all your valve train issues at that rpm.
Something is amiss, it simply needs to be identified and corrected.

Please clarify that the original issue was with the rocker arms rather than the shafts. Or is that incorrect?
Are we to read that the new replacements were cracked when you got them?
Do they have hydraulic cams or roller? Are the lifters hydraulic or solid?
All on the same engine, or across them both?

Clarification of the above would help immensely. Pictures would likely be a big help also.
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miata
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Re: cadd500 broken rocker shafts?

Post by miata »

Deano wrote:
Mon Jun 07, 2021 11:26 am
miata wrote:
Mon Jun 07, 2021 7:34 am
Has anyone else had rocker shaft failures while using the cad500 solid set?
I have 8 broken ones, replaced by, 8 brand new ones..... with cracks. All the cracks are in the drilled holes.
Anyone else seen this?
Is there a better alternative?
twin engines, these are workhorses. 3k rpm, full load for about 45 minutes at a time.
No, this is not a typical occurrence. Shaft rockers should've solved all your valve train issues at that rpm.
Something is amiss, it simply needs to be identified and corrected.

Please clarify that the original issue was with the rocker arms rather than the shafts. Or is that incorrect?
Are we to read that the new replacements were cracked when you got them?
Do they have hydraulic cams or roller? Are the lifters hydraulic or solid?
All on the same engine, or across them both?

Clarification of the above would help immensely. Pictures would likely be a big help also.

identical engine builds

valvetrain was upgraded at the advice of cadd500 to match their cam selection, solid rocker shafts, oem rockers. they sell it as a kit.

first set of solid rocker shafts lasted about 3 hours before they all were broken.

second set arrived, looked a bit different, seems to have added some sort of heat treatment. FULL OF VISIBLE CRACKS.

here is the first set. all broke in exactly the same place.

hydraulic lifters, meticulously set to the middle of the dry installation (calls for like .040-.060 preload)


the cracked ones that they just sent me, negates any questions i had about my assembly.
Attachments
broken ends.jpg
broken shaft.jpg
Last edited by miata on Mon Jun 07, 2021 1:43 pm, edited 1 time in total.
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Re: cadd500 broken rocker shafts?

Post by miata »

second set. some sort of flame treatment. 2 iterations of the same part is not a good sign.

visible cracks in every hole just about.


CADD500 just advised me to run the new ones with the cracks..

I have a hard time putting visibly broken parts into engines that cost me close to 20k.


check out the last picture below, one of the holes has like 5 cracks spidering around with rust coming out of them.


If this was coil bind related, I would have 32 bent push rods. but again, it was all part of 2 identical engine build kits anyway.
Attachments
broken4.jpg
broken new3.jpg
miata
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Re: cadd500 broken rocker shafts?

Post by miata »

just to be clear, this is not a post to blast the manufacturer.

Although, I feel like im about to just eat the cost of it all.

try overnighting hunks of steel parts...real cheap.

The radio has gone silent now, after telling me they are fine to use.
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Re: cadd500 broken rocker shafts?

Post by hdsadey »

I believe T&D Machine makes a setup for Caddys.
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Re: cadd500 broken rocker shafts?

Post by ARMYCOUNTRY43 »

hdsadey wrote:
Mon Jun 07, 2021 3:59 pm
I believe T&D Machine makes a setup for Caddys.
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Re: cadd500 broken rocker shafts?

Post by hdsadey »

LS is gonna require a gearbox to make any power. There is 3k plus expense per engine for gearbox, not to mention the props you have won't work (wrong rotation). LS won't make the power where the Cadillac does.

If your only turning 3k might I suggest a Ford 460 platform. With a 4.5 stroke crank you can make 557 cubic inches easy. Since this is not an airboat application your certainly not concerned with a weight penalty. Cast iron heads would make plenty of power at 3k. Prop to crank adapters are available from GTO. Wouldn't have the valve train issues of the Cadillac. Could build them for less than the Caddys maybe 2/3rds the price. At 3000 rpms the should last a lifetime!!! PM me, I work at an engine machine shop and we could quote a build for your application. Daniel
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Re: cadd500 broken rocker shafts?

Post by OneBFC »

Yeah, just run a couple of low $ LS or even SBC behind pretty standard gear box and you will be better off in long run.

I mean, if all you are swinging is 2x 76" whisper tips, you aren't making mountains of power to need a high strung engine at high RPM.

Choose a gear ratio that gives you the tip speed you need for the right wind speed and you are same o same o from where you are today but with an easier to work with engine platform with many decades newer engineering.

Probably save on fuel too, not that really matters too much I am sure. Up time is probably king to you.

Good luck!!
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Deano
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Re: cadd500 broken rocker shafts?

Post by Deano »

I'm sorry to hear of your experience with these rebuilds.
Unfortunately, you are not the only one to have had such issues.

I agree with your assessment that the quality of those parts is to be held suspect.
I would not install them either, as it would seem the ultimate outcome could already be anticipated.
Either way, I perceive you to have been lucky to get away with that scenario one time. Odds do not favor two in a row.
All of the ones I'm familiar with, or have used, have 1 solid shaft per head. I am now especially leery of that set up

Without beating a dead horse, there are two options that are better than this one you have exhausted.
T&D Machine and Rocker Arms Unlimited. I've used both over the years and the expense is the only drawback I'm aware of in either case.
I've not purchased either in long enough that I know nothing of current pricing.

https://tdmach.com/
http://rockerarms.com/

Did CadCo supply the springs you used as well? (not familiar with the 'kit' you refer to) Whether they did or not, Swamphunter voiced a valid concern about avoiding excessive spring pressure. A little more than stock is fine, but running at only 3000 rpms doesn't require big overly hairy springs. Be aware that going to another setup will likely require regrouping where your push rod length is concerned. Not a big deal, but something to not overlook.

On a different note, should you need to or decide to regroup, Daniel makes a very valid point that I will second. Without the complication
that we have for the weight difference, using Ford Big Blocks would easily allow for reliable 3k power without having any of the Cadillac complications or the additional expense of gearboxes and right handed props.
It's kind of a shame we weren't able to point out this possibility before you suffered your current frustration.
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miata
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Re: cadd500 broken rocker shafts?

Post by miata »

Spring seat pressure is only 100. so pretty light

the entire heads were purchased complete.

When I checked them, coil bind did occur at about .080" after maximum lift, so a little room, but not a lot.


All of my assembly seems totally irrelevant since the brand new parts they sent me are full of hairline fractures.


Those shafts with flame marks have never been installed. I took one end off the package while standing at my mailbox and could see the fractures.



I just built my own shafts last night from 4140. I was out of time. CadCo has gone silent and I have a customer showing up tomorrow.


Im really bummed out that they failed to carefully inspect this new set before they sent them, and then tell me to "just use them" as if it is ok to put visibly defective parts into an engine. I would have dropped another couple thousand bucks if they would have offered me a better replacement at a discount. But yesterday, after ONE phone call and One email, they just started ignoring me.

I didnt place any blame on CadCo, I simply showed them the pictures and asked what we should do to correct the problem.

Nothing was the answer I was given.
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Re: cadd500 broken rocker shafts?

Post by SWAMPHUNTER45 »

Call and ask for Courtney Hines
miata
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Re: cadd500 broken rocker shafts?

Post by miata »

SWAMPHUNTER45 wrote:
Tue Jun 08, 2021 8:32 am
Call and ask for Courtney Hines
I sent him an email. see what happens.
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Re: cadd500 broken rocker shafts?

Post by One Eyed Gator »

A .625 lift cam would require the proper valvetrain geometry and specific springs and setup to not coil bind, not just adding a shaft rocker. You did not say but maybe that was done.

That is a lot of stress running a cam like that at close to WOT for a long periods.

BTW glad my caddy days (run a DD caddy for 11yrs)

As for the LS topic you do need a gearbox but I have a stock 5.3 that had 113K on it before it went on the and it has over 600hr between 3 different boast mostly run at or over 3600rpm. You easily build 3 of them for the 20k in a caddy.

Just my .02
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Re: cadd500 broken rocker shafts?

Post by miata »

guys, they were complete "kits" from cadCo.

their kit includes

cam
cam gear timing set
complete heads
complete valve train for the cam

it is supposed to be all ready to work together.


furthermore- i was sent brand new parts with rust and cracks all over and throughout them.


the worst valve geometry in the world doesn't matter if the shaft is broken when I remove it from its packaging.
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Re: cadd500 broken rocker shafts?

Post by miata »

Got ahold of Courtney. The internet is a funny tool.

anyway, sounds like he was being bypassed and others were making decisions on his behalf, at my expense.

We seem to be getting a grip on the situation now.
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Re: cadd500 broken rocker shafts?

Post by bbboswell »

miata wrote:Got ahold of Courtney. The internet is a funny tool.

anyway, sounds like he was being bypassed and others were making decisions on his behalf, at my expense.

We seem to be getting a grip on the situation now.
This sounds better! Keep us updated
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Re: cadd500 broken rocker shafts?

Post by miata »

I ended up making my own shafts out if 4140, they got me through my last job for a few weeks.

CadCo did right all the wrongs.

I will be installing 2 sets of the Harland Sharpe solid single shaft rockers.


I am looking for engine alternatives. The caddy parts availability makes me nervous.

1. The engines are tools, not for fun
2. Must run in the worst weather conditions
3. I really need, according to math, about 500 ft lbs to get the wind speed necessary.
4. Pump gas
5. Ideally I want to increase to 4~6 engines, and drive by wire would be convenient.

I am interested to hear some ideas.
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Re: cadd500 broken rocker shafts?

Post by hdsadey »

385 series Fords. 460 stroked to 557. Hard to beat in the low end torque game!!!
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Re: cadd500 broken rocker shafts?

Post by Heavy »

IMO, I agree with hdsadey. Here is a link to a 385 series for that puts out 404lb ft of torque at 1600rpm. with the longer stroke and bore and a few mods in cam profile I would think 500lb ft would be easily achieved with minor added fatigue on the components used at a low RPM. Just my thoughts.

https://onan.xmsi.net/00-OEM%20Engine%2 ... 0sheet.PDF
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Re: An alternative to cadillac

Post by miata »

I am just a bit beyond experimenting by now.

I would really like someone who has a solid engine package already speced out with known results.

It also sounds like I ended up with these Caddies for a reason; they really do make a ton of power for pretty cheap.
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Re: An alternative to cadillac

Post by miata »

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kwanjangnihm
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Re: An alternative to cadillac

Post by kwanjangnihm »

miata wrote:
Tue Jun 15, 2021 1:52 pm
I would really like someone who has a solid engine package already speced out with known results.
I would start with Dave from WaterThunder! He has tons of knowledge & experience.

http://www.waterthunder.com/
He'll cut your throat, baby, stick you in the back, drive off in your Cadillac.
He's more trouble than you think, he'll kill your sugar, leave you in the drink.
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