Going by your username I'm guessing you work on "Yellow Iron"? It has been awhile since I worked on these and was curious, did they ever add lift pumps to these so that you don't have to pressurize the fuel tank and bleed all the injector lines when they run out of fuel? That was always a pain on CAT Engines.

 

Hmmm. I dunno - that bearing doesn't look too happy....

 

they kind of did and didnt almost all of the engines had and have transfer pumps built onto the back of the injector pumps. Old pump and lines systems or if you had a mechanical rack you always had to bleed the air at the pump,line or at the filter or somewhere. But some c-series engines either have a hand pump or an electric priming pump you just hold a switch down which is pretty nice.

 

Good catch Sir, it is worn a lot more than just spec. He's through the Clevite on that one and it is the Cap Bearing, the Rod side is normally worse from having more pressure put on it. I thought about suggesting he also mic the rod journals to see if they are still round. But that would have opened up a whole new can of Worms if they are flat.


It would definitely be very wise to slide another set of at least matching sized mains and rods in this while there. But as you know, Even this can sometimes be dicey without removing the Cylinder Ridge also. I'm glad you brought it up, a picture is worth a thousand words and I'm surprised more didn't mention that bearing? Myself included

 

I'm a little out of my depth on that kind of stuff (having only rebuilt one engine) but I figured someone more knowledgeable would mention it earlier, but when nobody did, I figured it needed to be flagged.

Sometimes things just get missed.

 

It's hard to tell my friend! With the great knowledge I have read you sharing here I was guessing you were a very seasoned builder in all aspects.


I hope you don't mind me sharing about the Ridge. What happens is as the Rod bearings wear, the length of stroke travel slowly moves down closer to the crank journal. This causes the Ring wear cylinder taper Ridge to also slowly move down closer to the crank. Depending on how deep the taper is at this point, replacing the bearings moves the stroke travel back up closer to new. Now there is a chance of the Rings hitting the Cylinder Ridge and breaking. Removing the Ridge will prevent this but of course the head will also have to come off to do this.

 

I was going to let this go, but it looks like you've decided to follow me around and take small pot-shots at me.

I suggest you reconsider that plan.

 

When I said


"It's hard to tell my friend! With the great knowledge I have read you sharing here I was guessing you were a very seasoned builder in all aspects. "


I meant it!!!


I was not being sarcastic it was meant to be a compliment!, The scope of your knowledge is very full and complete with these Rigs and I seriously do recognize and respect this fact my friend and meant what I said. You have the knowledge of a seasoned Builder! It would be hard to argue against this impression after reading and observing your knowledge here.


I am not following you around. I was just complimenting and replying to the last person who replied to the thread from yesterday. It just happened to be you when I got on this morning. (Your last Posts).


You truly are a warehouse of knowledge to share with those who are not as mechanically inclined. But your understanding, patience and delivery sucked man, I will be the first to give you credit for the recent friendliness you have shared.


Seriously... Noted, Respected and Appreciated. Thank you for sharing your knowledge in a more tactful and patient delivery! I'm a nobody but one thing I do know is you do not want someone saying that this board comes off as rude and lacking patience and understanding with those that are not Geniuses about Jeeps. (it's why they come here right?)


I was only trying to make amends and share some of my knowledge in hopes we could respect one another. In no way was it meant to be derogatory or provoking. I made only one comment to defend another user and I feel I had the right to do this considering I too was made into a public example of "Dumba$$" here by your domination.


Sorry, but it just ain't right, all you had to do was present a friendly request and I would have been honored to respect it. Now I'm just trying to agree with you in the posts because you are absolutely right about the situations being presented and I respect this.


Just trying to show you I respect and appreciate the knowledge you do share here man.

 

Yea ive been kind of curious about that grooving the bearing as you can see there is a half moon worn into the front side of the bearing and im kind of leaning toward bad thrust bearings etc. I dont like or do alot of spec work in what i do outside of hydraulic cylinders and such. I thought about about doing a main and rod bearing roll in, i just dont know if its too far gone to attempt without doing some damage down the line. The bearing journal is grooved more so than the bearing which worries me. As you guys have said before getting into that stuff can open up alot more issues than im willing to deal with right now. I plan on a rebult at about 300k or so i just want to hit a trail once or twice before i rebuild the engine I know from my job a late roll in can cause piston slap and alot of other problems but i am also going to get the opinions of some of the CAT veterans at work tomorrow.

 

Ive noticed they are kind of rough, thank you for saying something i was kind of aggrivated my whole thread was hijacked on the last page thats why i have not come back to it in a day,
Thank you for putting it back on track. At this point i kind of need an opinion on a bearing roll in (what we call it) .In heavy equipment most stuff is so bad we just throw cylinder packs in something and call it a day we dont bother mic-ing or anything (takes too much time,effort, money) which is why i am kind of at loss. I am thinking of running thicker oil in it and continuing with my build until something pops. Mind you it does have 283k on it and its days are numbered. But as i have stated in previous threads i can work on machines all day long no problem and diesel but I am mostly automotive illiterate and a jeep newbie so all opinions are respected and accepted!

 

May I suggest what we used to call a "Refurbish" rather than a whole "Rebuild"?


It consisted of pulling the head and removing the cylinder Ridges.


Light hone to the cylinder just enough to "Break the Glaze" and make a surface that would be just barely aggressive enough to break in a "new set" of OEM rings.


New main and rod bearings to match what it has now and timing chain.


Lap the valves, meaning just reseat them using grinding compound.


New oil pump and button her back up with a new set of gaskets.


The costs for this are as minimal as you can get and you can do it all yourself easily with the knowledge you already have.


The only tip I would like to offer is when you lap the valves into the seats use a drill on the back side valve "Stem" and pull them into the seat gently in and out until they have a consistent Grey "Grind" surface 360 on both faces. An old trick an old mechanic from the days of Model the "t" taught me.


Honestly, this will be enough to get you by for another at least 200k before the taper in the cylinder starts to eat at the Piston and Rings and it needs to be bored larger and require a full rebuild with new Pistons, Crank turn, Etc.


There are quite a few here including myself that would gladly walk you through it step by step. and only because the parts are much smaller than what you are used to. lol

 

i was also considering doing that as well like basically doing an in frame is what you are saying. And i really like the idea of it so you think that would really get me some longevity out of it? Ive read about some guys doing it to their jeeps before i really want to try it. See thats all stuff we do at work on skidders and some dozers i just never knew how effective it would be on a jeep XD

 

I am willing if you are willing.


First step...slide that Rod Bearing out of the cap and see what says on the back. Manufacturer logo? STND? STD? .10? .20 ?


This will tell you right away if there has ever been any machine work done to this engine.


This speaks volumes as to what might be where to go next. Sometimes it can immediately tell you it is ready for major work. I'm hoping they indicate OEM Standard specs you are working with here.

 

luckily i did not torque it back in this is what i got. B31.
f-12
6-5x
std
thats really what i can read its kind of hard to read
edit

 

<br /><br />A little late here but I saw no shot or insult taken. By what ive read, you were taken and compared to someone who knows how to rebuild an engine. Even if you've only physically done it once, you still have the knowledge to do so and help walk others through it. Myself, I have built eight different engines and designed two of those myself. Does that make me a professional? No but it does give me the ability and knowledge of what goes on and how to do it so that I may share with others. Just a little observation.