Got the motor in.

[mopar3.0]

the boys are right, i never took apart the rocker assembley on the secind new head,


my motor then blew up a second time when , the bas pan had a good inch of shavings in it, but im pretty sure this was because of the timming being retarted too far because of a wrong setting on my msd timming controller,
i was pissed and sold the car to buddie, then bought it back a year later with a stock engine lol

[jory]

hmm.. well originally the cam caps were from these heads, I swapped them onto an 87 motor with my cams and that ran fine for months. Then I pulled that motor out of my car and put the cam caps back on the original heads. That could possibly be it but IDK.

I pulled the oil pan and took off the main bearing cap, the main bearings look awesome. They had oil on them and still had some assembly lube on them too. No scratches or anything. The bores look good and the timing belt is still good. I don't know how I'll check the rod bearings if I can't turn the motor.

[mopar3.0]

remove the timming belt and try and turn each cam shaft, and you will know pretty quick

[jory]

The top end is good. Main bearings are good too. The #2 rod bearing spun for some reason and the crank is 10 thousandths out of round. So I'm probably going to use the crank out of my spare engine after I pull the motor this weekend.

[roguetrip]

Quote:

Originally Posted by mopar3.0 remove the timming belt and try and turn each cam shaft, and you will know pretty quick

Uh, turn the cams/crank slow, if anything like my stealth DOHC V6 the valves will hit the pistons, no reason on scratching/denting/bending things up on new parts

[Ondonti]

Um...how did it seize......?
I never had one with a bad rod bearing seize until one of them had the piston hit the head (junk motor from the back of my duster that I put about 20 miles on with a new bearing till it died).

You still dont know why it seized so i would be wary about just slapping in a new crank...Unless your rod bearing clearances were too tight.

[lookin]

Sorry this happened. You'll straighten it out though.

[Reaper1]

Also, if the rod bearing spun you will want to get that rod resized or replace that rod!! DO NOT just slap a new bearing and crank in there and think it'll be OK. It *might* be, bu from personal expereince...it probably isn't!

Also, I don't know the history of the build, but you said something about using a Diamante engine. I wonder if you used the pistons sirectly out of another engine or if they are new pistons? Either way, if they weren't fitted to this engine, then they could have expanded and seized against the cylinder walls. The other thing is that if you did not check ring gaps, they could also cause the same issue.

I agree with Ondonti though, you need to find out WHY it spun the bearing.

[jory]

Yes I do want to figure out why it spun the bearing. Good point on getting the rod checked. Maybe I'll use one from my spare engine. Every other bearing in the engine is good. The rods and pistons came from a Diamante with a good running motor, stock bore. I used new rings properly gapped, that was my initial guess also but all the pistons move freely in their bores and it didn't run long enough to get warm.

[BAKES]

i would check the oil gallery from the main being to suppected rod bearing feed hole for resriction due you have a pic of the rod shels you can tell a lot from the type of damage to a bearings

[jory]

Quote:

Originally Posted by BAKES i would check the oil gallery from the main being to suppected rod bearing feed hole for resriction due you have a pic of the rod shels you can tell a lot from the type of damage to a bearings

No but I can go out and take one right now, it's only 4 blocks away.

[Reaper1]

Well...even if they are cast pistons that came out the same type of block, that doesn't mean they are designed the same. I'd check the specs of the Diamante engine to see what the piston to wall clearance is supposed to be, then check that against your engine just to be sure. Yes, it ran for a VERY short amount of time, but it *could* be enough if the clearance isn't right. Even if they move freely, they will do that with just .001" clearance...

[Ondonti]

Bad rod bearing wont seize the motor if its getting oil (at least in my experience...even driving 1000 miles with lots of boosted driving)

If rod #2 didnt get any oil, its because the passage in the crank is bad, not the block.

Figure out why it spun a bearing.

Figure out what siezed (even if its just the rod that seized things up somehow). etc.

[Reaper1]

Actually I had a rod bearing seize an engine. My 'Baron's origional motor did that. I was on my way to the parts store to get the parts to fix the oil leak...it ran low on oil on the way there on the highway...spun the bearing...kept running 'till I got off the highway and as soon as there was no load on it, the engine seized. It was spun so bad that it wrapped itself around to the other side of the crank journal so the two bearing halves were on top of each other(yeah, they were thin too), and they got so hot they fused together.

Later when it cooled down it was able to spin over and run, but OMG did it make a racket!!! LOL

[The Pope]

My machine shop runs every engine on an oiler to make sure it all works. Then tear the engine down and look at everything. Then bolt it together and send it out. It is always a good idea to have a pro assemble and oil the long block, always worth the $.