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$44 /year ELECTRONIC

$60 /year USA

$77 /year International

D7E transmission FUBAR! Could really use big help! Very sad!

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2 years 9 months ago #234071 by Bmr
RIP ACMOC. I said my part got told to shut up guess what here we are again.....the dealer dosen't know what there doing help me for FREE FREE FREE....You want me to pay for real life experience.....don't worry my time of posting is short.


RIP ACMOC
thanks Jon

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2 years 9 months ago - 2 years 9 months ago #234147 by bobby1
Well.....some progress, and taking two steps backwards. I pressured the cooler, found the leaky tube, and decided to just let the radiator shop do the patch since they do it daily. I installed with the new, gray metallic type gaskets. I rigged up a test device for pressure test and now realize both of my gaskets leak............. Beyond pissed at the moment. I wondered if I should spooge silicone on them but that type of gasket usually seals decent. Bolts are pretty tight and air just pukes out. Thoughts on that? It was so much fun, I get to do it twice!!!!!

Wombat, I don't mind contributing. curious what the 'electronic' thing means? Does that by chance get me access to any other manuals? I have all the 75E military stuff, but they just suck! The print is bad, they are vague, and I can't even find a torque value for the cooler. I realize some people guess but if they should be 120 and I am at 60, that could explain a leak.

Oh, and the pressure relief valve showed me where it was! lol Popped pretty close to 15psi and now a leaker so I will have to take that apart. right now I just put a plug over it so I can pressure up and do more checking. Finding plenty of leaks. Hard to check that radiator though.

I had one thought.  Being in engineering, I realize torque on a bolt is rarely covered at detail.  Dry torque is largely different than oiled, then on up to greased.  Reality is torsion is applied, but I did not lube the threads which would allow me to torque to probably an even lesser value and get way more axial tension on those bolts.  Thoughts?  The bolts would nearly walk in with fingers, but I did not do anything to clean or lube them.  Given this issue, and the large gasket surface area, I am wondering about at least trying it?  

 
Last edit: 2 years 9 months ago by bobby1.

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2 years 9 months ago #234171 by edb
Hi bobby1,
scan below is a traditional Cat general fastener torque chart.
Cat explain that the Max. Min torque figures given for each fastener is the variation in torque wrench allowance--that means set your wrench to the median setting and it will be between those figures--maybe depending how accurate a wrench is--these days Quality Assurance means all our wrenches need to be certified yearly ( or was) here down under.
The lubricant used if needed is usually given in the Service Manual Specifications section along with the specialty torque needed.
Generally plain old engine oil or chassis grease ( not Moly. grease) is used for ease of disassembly in future.
There are other specialty torque figures for Hydraulic Valve Body (including Transmission Valve Bodies) fasteners as well as Taper Lock Studs in another chart scan below.

Others experience may vary but this was what I was taught at the Dealer.
Cheers,
Eddie B.
Attachments:

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2 years 9 months ago #234172 by bobby1
Thanks edb. Looks like pretty std torque specs for grade fasteners. I generally hug the low end when applying grease. Any input in the leaking gaskets? I am pretty surprised they both leak pretty good. Spent plenty of time on them with a razor blade and not my first rodeo. I'd say the material mimics the stuff common on B&S small engine head gaskets. It's the type you typically would not add sealer to, but on a head gasket, there are a lot of bolts to lay down some clamp force. This is not really the same.

Now that the assembly is 100% installed, I am trying to find a short cut. I didn't even look to attempt removing the back cap on the cooler under the starter. I pulled the bolts on the cap that secure it to the engine as the whole thing needed to come out anyway. It is almost looking like if I can't grease and retorque to get a seal, I will have to pull the whole thing out again.
I am really cussing why in the world they used gaskets over Orings for this. An Oring seems a perfect seal for this application. Makes little sense to me. Just frustrated. I don't like rework.
The following user(s) said Thank You: edb

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2 years 9 months ago #234174 by edb
Hi bobby1,
at the Dealer I was taught to check all flat surfaces with a ruler for flat along the sides of the flanges--most often flanges are drawn over at the fastener holes by others trying to stop leaks or over tensioning the fasteners and so leave low spots between the bolt hole areas causing the issues you have.

I simply file along the bolt hole line length wise between the bolt holes to file them flat, then I lay emery strap under the file and smooth the surfaces well--being pedantic I guess but it never let me down and few if any re-do's on all gasket surfaces--yes it takes time but more often than not it saves time when having to go back and R&R the parts and re-do it anyway.
I guess these days careful use of a sanding belt would soon have the task done--have seen items ruined by sanding haphazardly.

My mentors taught me to "do it properly once" and it rarely failed me having done so.
Cheers,
Eddie B.

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2 years 9 months ago #234181 by Cat Yellow1

My mentors taught me to "do it properly once"


Very good advice.  Thanks Eddie.

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2 years 9 months ago #234201 by bobby1
Well so far the cooler is leak free. Apparently it needed the slobber. Had to pull it, even put layout dye on and ran precision parallels on things. Nothing was terrible. Ran black RTV, lubed bolts and went to 80lbft.

Anywho, still chasing air leaks as I work through the cooling system. Still no clue on the trans but really want to know cooling system is decent before I fire engine. During air testing, I can hear something leaking, though I cannot find the source at all. What I fear is it is under the valve cover. It seems to be coming from the top of the engine area. I am hoping for a freeze plug, line I am missing, etc? I do suspect the engine has been overheated but that is all a hunch. Do these heads love to crack when hot? If so, is there a likely area? I am running soap on everything. I hit all the freeze plugs I can see and cylinder base. Nothing has showed up yet.

These are wet liner engines, correct? Or no? I am getting more nervous if I can't confirm the source of these leak. I did open the oil filler neck and did not detect any air there. When I say "leak", I mean a small leak that takes about 10min to bleed down from 10psi test pressure.

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2 years 9 months ago #234204 by edb
Hi bobby1,
there are core plugs in under the valve covers in the top of the heads that I have seen rust out in poorly maintained cooling systems.

These heads are known to crack but mostly from not cooling the engine down as described in the OMI--they need to fast and then slow idled for a period of time to let the cooling system and especially the head surfaces normalize before shutting down.
Pre-combustion chambers can rust thru is poorly maintained systems too--with heads that are cracked it is usual to find the Pre-chambers are loose or slightly loose to unscrew.

Engines are wet liners and again in poorly maintained systems have been known to rust thru at the liner to lower block bore due to crud build up over time.
Overheated liners can leak at the lower liner seals where the liner is in the block.

Suggest to keep working at the easy to fix cheap and simpler things until there is nothing left but the hard and costly stuff.

Cheers,
Eddie B.

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2 years 9 months ago #234207 by bobby1
Felt I needed to take advantage of the zero wind. Despite being cold and me falling off the dozer hood and right on the dirt, I have confirmed air is leaking around the back cylinder injector/glow plug area. I loosened the valve cover and could not get a tone change, but I finally found some bubbles around the injector line. I am now trying to find info on that. Not looking too good so far.

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2 years 9 months ago #234208 by poor farmer/logger
Just read through your adventure with your new to you machine. Hopefully you can get it sorted out and working again. Is a shame to see the older stuff scraped.

If you need a new cooler I was able to get one through g t engine parts in Florida. It’s not quite as good as a original cat and I haven’t ran in yet but it appears to be of decent quality. It’s a cast housing vs the steel one of the original.

I just had my suction screens apart and cleaned as well. I had no issues with it before hand but I was quite surprised at how much stuff was on the transmission pump strainer. I don’t think it had been apart in years. No big chunks but it wasn’t pretty none the less. It’s more awkward to get to so I think it tends to get forgotten.

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