2000 Mack 689s unknown metal rings in oil & broken rocker bent

[Trumbull_welding]

Good morning all,

     I’m new to this site and this is my first post I am a mobile heavy equipment mechanic and welder I’m happy to have the opportunity to share this with y’all and hopefully someone here has seen something like this before… so here’s what’s going on first of it’s a

2000 Mack RD690S
Vin 1M2P264CXYM030963

197,000 miles 

     So this truck is one of many I do service work on during an oil change about 4 weeks ago on the plug magnet I got a few small round pieces of metal only way I can think to describe them is if you took the spring from a pen and cut it into a bunch of small metal rings I’ll attach pictures below… I notified the company of my findings and they continued to run the truck there mechanic told me it was running rough and he adjusted one of the rockers a little tighter which cleared it up it went another week or so and developed a rough idle again to which there mechanic again tightened down the same rocker more, now to me this would go to say that the cam is being eaten up. The truck again went back on the road and this time came back with a bent push rod and a broken rocker on the number 3 cylinder I will attach pictures below in order being 1 the metal components found on the magnet, bent pushrod and broken rocker / broken rocker pieces, contents of oil pan after pan dropped and cleaned out, and lastly a not so good picture of a cam lobe with a chip missing. I hope someone here has seen this before and can help me figure out what these pieces in the oil are, also would you guys throw on a reman head, cam shaft and new push rods or replace rockers on the current head in place and replace cam and push rods, I’m also concerned to do all the work with this mystery part still possibly breaking down and dumping these rings in to the engine possibly to just cause the same issue again.

Thank you all in advance for you help I look forward to chatting with you all soon.

-Chris 

 

[Onyx610]

Looks like an H-ring failure. 

[Trumbull_welding]

Here’s the rest of the pictures it only let me post 3. Here the contents of the oil pan after removed and an unfortunately not so good picture of the cam  

[Joey Mack]

Those rings look like rotator rings.. check the valve rotators, and use a magnet stick to reach into all the corners of the top of the head, and inside the heads of the core plugs.  I assume that chunks are lifter chunks.  Do you have the ability to check the H-rings.. ?

[67RModel]

Just to be clear is the broken rocker arm and bent push rod the one the mechanic adjusted twice? 

[Joey Mack]

Back to the first posting... Since you have this much damage and still haven't checked the rest of the cylinders, I suggest you look closely at both heads, on the top for more of those spring coils.. that indicates bad valve rotators and replacing rotators is a little bit of a job.  The valve seals will be replaced at the same time, then you have to wiegh the fact tha the valves should be lapped or ground, then there is tooling, knowledge, and down time... All of these combined, may steer you towards 2 re-man heads, just to get that part done.  The cam is likely JUNK.. the H-rings,,,. At the very least should be replaced on the bad cylinder.  Are you familiar with H-rings inspection, and installation? And choosing the correct size H-Ring? The rocker shaft needs to checked really good for re- use,. I will stop here for now.  Keep posting..  Jojo

[Trumbull_welding]

Thank you all for the responses.

Joey Mack- How would I check the h-rings? Just checking for hight and orientation and compair to other cylinders? Do the heads need to be removed to check? Obviously they would need to be removed to replace. And your saying those rings would be inside the valve rotators?

Also the rocker shaft has a hairline fracture/crack i apologize I failed to include that before..I was also leaning toward head replacement.      
 

    No I have not dealt with h-ring inspection or replacement. My understanding is it would be a press fit is there somewhere I could find a procedure for correct sizing and replacement? 

67RMODEL- correct it was the same valve and to my knowledge no other valves were adjusted whatsoever 

[Joey Mack]

H-rings can be checked from the bottom with the special tool. However, installation, is done from the top with the heads off..  it is easy to do. The book explains it in simple terms.. you may need to get oversized H-rings if there was excessive movement of the original H-rings.. the tools can be bought from Freedom Racing.com for about $350.00+. 

[fjh]

I'm onboard with the H ring failure ! However Them little circles are a puzzle for me! They look valve guide size or  eup plunger sized ??? Could these be pulled threads from something??

[Joey Mack]

They can be threads, but I believe he said they are the size of a ball point pen spring. Inside the valve rotators is a coil spring.  We had many issues with them breaking down and had to replace them,. I believe we went from top rotators to bottom style.  

[fjh]

3 minutes ago, Joey Mack said:

They can be threads, but I believe he said they are the size of a ball point pen spring. Inside the valve rotators is a coil spring.  We had many issues with them breaking down and had to replace them,. I believe we went from top rotators to bottom style.  

If you say so never seen these before Going to be an egdecation 🙄 for me I will sit back and watch this one!

[Joey Mack]

There really aren't any corners to cut here... I highly recommend the H-rings tools,, if they are NOT set at the correct depth and 'clocked' correctly...  The CAM WILL GET DESTROYED IN THE FIRST HOUR...   jojo

[fjh]

21 minutes ago, Joey Mack said:

There really aren't any corners to cut here... I highly recommend the H-rings tools,, if they are NOT set at the correct depth and 'clocked' correctly...  The CAM WILL GET DESTROYED IN THE FIRST HOUR...   jojo

yup! can't just eye ball this job!

[Joey Mack]

The rocker shafts do NOT come with the heads..  I don't mean disrespect with my next question.....  How well do you know these engines? If you have engine building experience, then doing this job won't be hard, just some new aspects. Many of us here can guide you.  And many of us have the service manuals to look up info..  To repeat myself.. The special tools are essential.  Jojo

[Mackpro]

 https://macktrucks.vg-emedia.com/ProductListing.aspx?keyword=H-ring   Here are the two bulletins on h-ring checking 

[Trumbull_welding]

Thank you all again for all the info I do have experience rebuilding mostly Cummins or older cat this will be the first Mack motor and it looks like the customer is leaning toward doing an in-frame I’ll keep you posted on a start date for this project and etc..

-Chris  

[Joey Mack]

Looks like you got a handle on it..  Good Luck to you..  jojo

[Joey Mack]

If you need info on essential tools, like a cam shoe, lifter sticks, H-Ring installer, and so-on..  Please let us know..   at least 5 of us will help you     jojo

[Trumbull_welding]

Good evening,

     Just wanted to reach out for all those who answered me here and helped me out or anyone who is following along. 

*update*

     The company has parked the truck for the time being, they had a few breakdowns and some pm i had to take care of, i currently have one or two larger projects to wrap up with them. I’m hoping to be starting the rebuild in the next 1-2 months in the mean time if you guys would be willing I’d love to start getting together any of the Mack specific tools ill need to get this done i know i need the H-Ring tools you’ve outlined above are there any other necessary tools needed or even non necessary tools that will make the job easier?

Thank you all again in advance!

-Chris

[Joey Mack]

H-Ring tool,,,,,  Cam Shoe,,,, cam bushing driver,,,, Engine Barring tool,,,, Magnetic lifter sticks (mine are home made and cost under $50.00),,,, Sled gauge with a dial indicator,,,, Depth mic. 4'' plus length. The counterbore is 4.003'' deep.,,,, Liner puller,,,, if you dont have a liner press, mine is homemade. you can drive them in with a 5# Dead blow hammer and a piece of good plywood,,,, A medium sized toaster oven,,,, front main seal installer,,,, [(2) .010''] / .016'' / .024'' / .021''  feeler gauges,,,, 3/8'' torque wrench,,,, 1/2'' torque wrench,,,, ..  If i forgot something I will post it...  Jojo

[Joey Mack]

This is what I use to seal the H-Rings inplace.. It is a cross reference for the Loc-tite product that is in the engine book..  Do you have a Mack E-Tech book? 

[JoeH]

Anyone else cringing that the company mechanic tightened down on that one valve not once, but twice?...

@Joey Mack is beyond edumacated on these engines, it's crossed my mind to try to convince him to drive to PA if I ever have H ring issues on my 2003 ETECH.