sambroom

I do. I was planning to get the specs out of the service manual, unless anyone has them handy?

Bugout4x4

They are all over the place on here. lol Just do a quick search.

Rod bearings??? lol

sambroom

Whoops, I was talking motorcycle. Yeah I'm talking about the timing chain cover. Is it ok to clean it and use rtv, or do I really need a real gasket (i have just used r tv on similar applications on motorcycles before)

The new crank is out of a motor of the exact same casting. I double checked to make sure the bearings from one motor fit the others crank, and they do. Just to be triple checking, I'll compare them with a micrometer tomorrow.

I stopped for tonight after I removed the bad crank. Not too bad to pull it out the bottom actually. I took a pillow under there with me for my head. I barely scooted the transmission back so I didn't have to disconnect anything but the main bolts around the bell housing... I could not get at the flex plate bolts, but it wasn't a problem to just drop the crank with the flex plate attached. I'll just bolt it to the new crank before installing. All the other bearing parts of the crank were flawless like they were just polished. It's a shame that darn thrust face got destroyed on this otherwise flawless crank. What the back could have caused that? It's kind of nuts.

I'll probably have to get a buddy to help me put the new crank up, at least until 1 and 7 are threaded.

Bugout4x4

Using RTV on the timing cover will seal it for awhile but eventually it will seep. What I am getting at with the bearings is if you had that crank rebuilt, they more than likely turned it down undersized like .010 or .020 under. So if they turned down the rod journals also, new bearings to "fit" the new undercut size have to be used, It is imperative. Besides you never want to put used bearings back into a bottom end. especially on the rod journals. You will hammer that crank flat and lose oil pressure in just a few thousand miles.

What size is on the back of the bearing set they gave you? .010? .020? If they surfaced the rod journals also, then more than likely they would have been cut to match the main journals. (that's the common practice anyways) The term would be a 10-10 crank or a 20-20 crank because both were cut. If both main and rod journals were cut when they did the crank you absolutely need ALL new bearings matched to the new size, period. Casting number has absolutely nothing to do with these differences.

That crankshaft and bearings are not smart enough to know what engine they belong in, all that matters is what size they were cut and this is universal practice for every crankshaft in every engine.

Don't try to cut any corners with this, You will be sorry you did, and we wasted our time to help here... Why did you ask for help if you are not going to listen???

sambroom

Sorry, I misunderstood what you meant before. Yes, I understand that if a crank is ground it needs adjusted sized bearings to work (Ex: if 0.010 is taken off the crank journals, you need bearings that are 0.010 bigger, or you will have too much gap and play, that will hash the crank)

The crank I took in only needed a bit of polishing on the mains, no grinding. No work was needed at all on the rod journals. Measured with the micrometer, all the mains are the same as the unmarred mains on the other crank. So the bearings the machine shop supplied are all the OEM size, no undersize or oversize. I got both the rod bearings and the mains.

No corner cutting here. This project has been a big enough of a PITA as it is. I would hate to have to do it all over, or worse!

Bugout4x4

Thank you Now I can sleep at night knowing you did do it right. Cause see...you have now included us in this project also, and there is a guilt by association factor in this. From what I see of the community here is that they are staunch believers in taking the time to do things the "right way", me too.

Just a friendly suggestion... but you may want to consider slowing down a bit. You got yourself into this whole mess because you got in a hurry and didn't take the time to take the pan off and check that engine out before you put it in. This all could have been prevented man.

sambroom

I seriously appreciate the help I'm getting from you guys. I'll do my best not to let you down.

I also wish I had more thoroughly checked the engine out before putting it in. Really I just didn't know enough getting into this to think "Maybe I should pull on the crank to check for endplay..." because I didn't know what endplay was, or that it could be an issue. I also didn't understand that a bottom end could have issues that weren't manifested in compression loss or running noise. The seller showed me a video of the engine running, and it sounded smooth. I just checked compression before I bought it, saw it wasn't leaking anything and thought it'd be fine. I'm definitely learning some of these things the hard way, but the good news is lessons learned the hard way are never forgotten, and maybe my experience can help others.

My family needs this jeep running because we are down to 1 car and my wife has to cart the kids around during the day. I did the motor swap here a little and there a little because I usually work 60 hours a week and have a long-ish commute. I ride my motorcycle to work all summer so I could afford to take my time with the engine swap the first time... and it it took 3 months. When it was finally done, and I discovered the crank issue, it was pretty heartbreaking. And worse, now that the mornings are in the 20's and 30's the motorcycle is no longer a good commuting option. SO, long story short, I have arranged some time off to just knock this jeep out, with the goal of finishing it in a week or two. So yeah, I'm getting a lot done each day, but I'm also doing my best to learn everything and being extremely thorough. By taking time off of work I have given myself plenty of time to do everything right. I'm not rushing, I'm just putting a lot of time into it each day.

Bugout4x4

I understand your situation more now and apologize for being judgmental. I have been in those tight situations because of survival necessity before myself several times and had to get one up and going ASAP. A couple of times I had to bail on one nonstop for two or three days in a row nodding off under the car to rest a few minutes here and there. In fact I am in one now but I am waiting for parts to come in. My Jeep went down a couple months ago and right now it was the only second vehicle we had running.

We are in a very rural area and have to drive 75 miles one way just to get groceries and supplies. In the mean time my 82 year old father who is getting dementia decides to take a trip to town with the other only vehicle running right now and caused an accident. It still runs good and everything but the insurance company decided to total it on their books. Because they totaled it I now have to shut it down, go get a salvage title, have it inspected, and then have it reinstated as safe to drive even though it only has minimal damage to the passenger side door and runs just fine. So I am now pressed to get the jeep going to drive while I shut down the other vehicle and deal with the salvage title issue before my policy expires.

The insurance company will not renew because they already totaled it, and they have entered this into the national database that it has been totaled so now I am not going to be able to get insurance on that one at all until I go through all the legal red tape first. It's a mess... But I am still taking the time to do it right because it is so sorely needed, and needs to be dependable when done.

I greatly apologize for the kneejerk reaction Sir. It is good to see you hitting it hard to get it done! It was just my concern that it does hold up for you after you get it done.

Lesson learned in mine is Dad will not be driving anymore. I can't take much more of this perpetual 24-7 damage control because he is on autopilot without a clue now, he is going to hurt someone or himself next time.

sambroom

Thanks Bugout4x4. Best of luck with your stuff too.

On another note, I was looking at my crank again a bit more closely, and I'm a bit worried with how it turned out. It had a couple of small grooves, but was for the most part like glass. Now, the grooves are smoothed out a bit but not entirely (they do pass the "fingernail test"), and the surfaces as a whole have taken on a slightly more brushed look. Is that how a fresh polished crank should look, or should it look like glass? Here is a video of the journals post-polish:

Bugout4x4

Know what? I think you are good with that as long as it is still within oil clearance tolerances. That really does not look bad for a used crank. Mine is about the same. But like someone very wisely mentioned earlier in the thread, be sure when you do put it in you cover the rod bolts with some rubber or plastic hose like fuel hose so that you don't nick it. You nick it and it will be toast and eat the bearing.

Right now "Plastigauge" might be a better friend than the calipers. Torque everything down as it should be with plastigauge under at least one rod cap and one main cap then pull just those two loose to see what it reads. And unless one of the old bearings spun on that crank, they should all be pretty close to the same and if those two are good you should be good to go.

dave1123

Plastigauge is a wax based thread-like material that squeezes when you torque the bearing. It comes in different colors depending on the clearance needed to measure. The whole point I wanted to make is DON'T TURN THE CRANK when torqueing it with the plastigauge in the bearing or you won't get a good reading, or any at all. You measure the width it squeezed to with a gauge on the paper strip it comes in.

This is the only way of knowing what the clearance REALLY is and I wish I had invented it! (UK-1948)

Bugout4x4

Absolutely Dave! And to keep from turning it check these two last with one of the rods parked easy to get at so you don't have to turn it again. I would say just check these two first, but I'm not sure you would get a truly accurate squish on the plastigauge unless all the others are already torqued down tight. Rod maybe, but not so sure about the main.

And you know what Dave? I always take the extra time to do every journal. I have bought bearings that were mis-marked, and had machine shops turn one journal down more or less than the others. Saved me from having to do it all again several times. That second rebuild for a customer for free is a killer on your profit margin.

dave1123

Yeah, I even check piston ring end gaps when rebuilding an engine as well as checking piston fit with a feeler gauge. Leave nothing to chance!

Of course I remember a certain 57 Chevy 283 that we stuck used pistons, rings, and bearings in from a 56 that was sitting in this guys yard without checking anything and dragged it all that summer and it stayed together! Corvette fuelly cam and a big Holly!

Bugout4x4

Honestly, I saw some stuff stay together I thought would never hold up. I watched a guy remove the ridges on a 302 with taper that was at least 40 or 50 thousands or more and only replaced the rings. It had slap when he fired it up and he actually made it all the way across the country with it pulling a heavy trailer. But not sure I would bank on that. lol

sambroom

I picked up a set of plastigauge when I picked up my gaskets (I got the timing cover gasket after all) What actually is the gap speck on these? I got each of the three colors.