Hi, I have a 360 I'm rebuilding. took it to the machine shop, got 030/030 - previously 20/20 on the crank. 060 bore on cylinders as they were previously 040 and had a sleeve in one cylinde. Shop also put new pin bushings in the rods.


Bearings were all sitting in the main journals when I broke it down, no evidence of spinning/scarring. Same for the rods, all the bearings were nice and tight in the rods (though definately worn). I did notice that the rods were not matched, I have 5 that are #8 , with few matching numbers on the caps, so rebuild shop that did it previously must have just pulled em out of the pile. Anyway, I cleaned the rods up with wire brush and 1000 grit


I did put a mic on the crank and all the journals are in spec before install. Put my T guages in the cylinders and the shop did a good job, no problems/out of round or taper there. Plastiguaged when putting in the mains, all good. Gapped and filed all the rings before putting on the pistons. numbered them with a sharpie to keep track


when putting on the mains, before installing rods/pistons, it stuck a bit/was hard to turn, required 2 hands.. i pryed it back and forth to set the thrust, like they say to do in the shop manual (74 F250) and it freed up where I could turn it smoothly by hand.


Then, when installing the pistons and rod bearings, it got progressively harder to turn on install (which makes some sense, as each piston is more friction). I was only tightening the rod caps to 25ftlbs, because If I torqued them to 45, it was really hard to turn over & was planning on torqueing to spec at end. BUT, when installing #7 cylinder, I just could not turn the engine over. Backed off the rod caps of #7, and it freed up. Then put in #8, same thing, but this time won't turn, regardless of what I loosen (including the mains). I was using some spray oil in the cylinders - bad move?


Tried loosening up all the mains. No luck. One thing I noticed when putting the pistons in, is a couple ofthe rod bearings would pop out or spin a bit in the journal when tapping on the piston into the cylinder & I'd have to pull them out and start over. could they be spinning out when bolted down causing this because I didn't have them fully torqued?? I figured I just gave it too hard of a shove with hammer handle


Any suggestions on best way to get this thing turning so I can pull all the rod caps and pistons out and start over would be appreciated. And any suggestions on causes? and if you have some suggestions on how to put the pistons back in the "right way", if it sounds like I'm doing it wrong, let me know. I just started at 1 and ended at 8.


btw, its staying a 360, as its going in a truck, used as a truck and a 360 is a fine motor for a simple 3/4 ton truck making runs to the dump, junkyard, moving stuff. If I wanted a bigger motor, I'd put a 460 in it and be done ( or put in the 390 thats been sitting the garage for 2 years that I built when reading all this BS here about how a 390 is better than a 360 ).


Sorry for such a long post, just I hate to admit defeat and take it to the shop for assembly, prices double when cleaning up someone elses mess

 

First of all, there is something definitely wrong. You should be able to turn the crank smoothly with one hand after the mains are torqued to spec.
Is there a chance you mixed the main caps? These are line bored to the block and have to go back in there original position. Same goes for the rod caps. These can't be mixed. The same cap has to go on the same rod, it also has to be installed so both lock tabs on the bearing are on the same side.
The bearing needs to be seated. You said a couple came out on installation, did you get the bearing seated and the lock tab in the groove before installing the cap.
Were the new rod pin bushings honed to size?
The other things to check would be dirt/grit on the bearings, when you're dealing with thousandths of an inch clearance, it doesn't take much to mess things up.
Were the rods checked for straightness and twist?
To disassemble, I'd start with #7 rod and go from there. Get the ones out that you can unbolt and knock out, it should get progressively easier as the rods come out. Take out all the rods, then remove the crank and start over. Double, triple and quadruple check the cleanliness, cap location and position and make sure the bearings are correctly seated.
I'd also put the crank in a set of v blocks and check for straightness and put a straight edge on the mains to check for any warping.
On disassembly look for any scoring on the bearing surface, this would indicate dirt/grit was present, also inspect the backside of the bearing, dirt between the bearing and it's seat will have the same effect and cause it to be hard to turn/lock up.
Look for any unusual "wipe" patterns on the bearing surface.
Good luck.

 

thank you Mike. Definately this motor sat broke down for a while and I was not certain of the mains. Will have to play with them I guess figure out the right place for them.

The rods, well, I have 5 #8's, and a mix and match on the caps. Will have to just emory cloth them and find the best fit for them I guess.

Will do on the other stuff.

justin

 

On the main caps, two are obvious, the rear and the center main cap. That leaves three that could be questionable as to location. On mine, there are arrows cast into the caps that shows how they're installed. In the center of the arrow I stamped the location number.
If yours weren't marked, what I would do is install the rear and center cap because those are a given. I would then just install the other three and try turning. If it doesn't feel right remove the three and reposition them. Keep this up until the crank turns free. Of course, the proper way is to install the caps and have the engine line honed.
As for the rods, you'll need to do the same thing but this one has a lot more possibilities with five #8 rods. If the other three rods are okay you might consider having the five resized at the machine shop. Other than that, it's mix 'n match time.
Again, good luck.

 

Would also help to have an inside mic to check the roundness of the rods when they are put together.You machine shop should have marked everything when they did work. Makes me question the quality of work they did.