Changing mains and con rod bearings while motor in truck

[drizler]

1990 2500 K I pulled the pan to change the oil pump due to sudden pressure drop so checked the bearings too. Bearings need it too but crank is ok. I managed to pull the rods bearings and even drove out the upper main shells using a ground down screw head inserted into the crank journal. Now I am having trouble getting the upper shells back in. Got two centers back but the front . rear are giving me fits. The second one in sits right over the pumpkin so that one should be the worst if I can do it there at all. What's the secret of shoving them back in. Bearings are .10 over everything just like what came out. Can you deflect the crank a couple thou by pushing on the crank pully or am I stuck pulling the engine? I've got more grease and cuts than any venture in recent memory here so somebody tell me the secret before I run out of grunge duds or wear the wheels out on my creeper. This really sucks.

[MagicRat]

The bearing shells are designed to have a 'crush' fit, that is, they do not fit perfectly until the cap is torqued down and crushes the shell into place. This is why the old ones come out easily but the new ones are a bear to install.

You should use a bearing removal and installation tool, which fits into the cranks oil hole in the journal. Then you can gently rotate the entire crankshaft. The edge of the tool will catch the bearing's edge and push it out.
New bearing shells are placed on the crank journal then rolled into place by turning the crankshaft. The tool will push the shell into place.

Obviously you have to pay attention to the notch, so the shell's notch fits the groove just as the bearing rolls into place.

You definitely do not want to use any kind of metal punch to remove or install the bearing. Its far too easy to nick the crank. Even a tiny nick will score the bearing and may cause future problems.

These bearing removal/installation tools were a simple nylon plug with one flat end, that would push into the journal hole. You should be able to buy one, hopefully. If you can't find one, I've read that a spent (not live) .22 cal rimfire brass shell can be used - but I've never used one (for this purpose, anyways).
A small split pin (cotter pin) can be inserted into the hole, and the 2 ends flattened out, into a T-shape, then inserted into the oil hole. The top of the 'T' will catch the bearing shell.

[drizler]

I also learned that I need to pull the Serpentine belt too. Hopefully that will let it drop enough to slide in. I sure hope so because I'm pretty sure a 22 case won't push straight enough to start the things in. I'll let you know.

[Schurkey]

I wouldn't waste ten seconds dicking with bearings in-the-chassis.

Did that once, in trade school. Never again.

PULL THE ENGINE. Do it right.

[DeltaP]

Agreed... pull the engine. The mains need to be done first. The thrust bearings prevent the crank from walking back and forth. You can f@*! the crank up seventeen different ways doing it like this!

[drizler]

You guys are right, I already scored the front upper bearing and aint no way its happening like that so out it comes. I pulled the pax front fender while I was at it for easy access. It was shot anyways and I have a donor truck in the field. Got everything loose / off today but the 4 9/16 bell housing bolts . Can't wait for those because there is no good way to get at them with the air wrench. I even pulled the grill, rad and ac cooler and even took the fan blades off just to clear ALL the bendable breakable crap out of the way. I have tried to "work around" so much stuff this week that my new philosophy is wanting all that shit GONE. By the time I am done it;ll be a new truck, yea right. I figure another 3 years and this thing is going to be heading for the smelter anyways so all it gets is bearings unless I encounter anything else going on. I guess the 3 day quicky is turning into a week and a half of fun in the shop part time. Any great advice on the best way to get at those 4 bell housing bolts? I'm tired of learning on the fly. The last time I took a 350 out of a car it had ALL US size bolts.

[MagicRat]

Originally Posted by drizler

Any great advice on the best way to get at those 4 bell housing bolts:

Yeah, if you've nicked the bearing, you may have nicked the crank journal as well.
Generally it's best to at least polish the crank journals with fine emery cloth, which it tough to do while its still in.

The last time I pulled the engine in one of these was ..... in 1990. I used a 3 ft long 1/2-inch drive extension bar with a swivel joint at one end to get the bell housing bolts.

If this is a 4x4, use the bar. You can loosen /lower the tranny mount for a bit of access.

If this is a 2wd, I would be tempted simply to pull both the engine and trans at the same time. It saves some time in lining up the bell-housing during reinstallation. It also gives you a chance to look at the tranny mount. If its original, its probably shot

[drizler]

Originally Posted by MagicRat

Yeah, if you've nicked the bearing, you may have nicked the crank journal as well.
Generally it's best to at least polish the crank journals with fine emery cloth, which it tough to do while its still in.

The last time I pulled the engine in one of these was ..... in 1990. I used a 3 ft long 1/2-inch drive extension bar with a swivel joint at one end to get the bell housing bolts.

If this is a 4x4, use the bar. You can loosen /lower the tranny mount for a bit of access.

If this is a 2wd, I would be tempted simply to pull both the engine and trans at the same time. It saves some time in lining up the bell-housing during reinstallation. It also gives you a chance to look at the tranny mount. If its original, its probably shot

A guy I know who has done a lot of them this way and he said it's way easier to just pull the tranny and engine together. Since I had such a PITA experience doing my grand cherokee not getting the splines in mesh the last time I think I'll just do that. As I recall there's not much that is hard to get to down tranny way and I have enough clearance to swing it all with that crane and equalizer bar. Fun fun but if I want my boat back in action its gonna happen one way or the other soon.