Is this what you need, Steve? Closest I could find.
Mains sticking to crank...
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- #62
Mark W said:Having something that abrasive in my hand makes me nervous when I'm looking at a crank at the same time.
Mark...
Mark-
My statement about " wondering when this was going to start " was directed at the double entendre, not about you second-guessing me...
" a word or expression capable of two interpretations with one usually risqué "
I was surprised that there were not more crank comments...
I understood the rule of thumb to be 10 psi per 1000 rpm running and around 20 psi at idle...Poser said:
Nick
Yeah, I guess the pressure is OK. Before I got my cruiser
I think the PO did top end rebuild and I don't really care for
those. I run 15-40 in the winter and 20-50 in the summer
cause that's what all the smart people around here
recommend. According the Nick's formula, I'm doing
pretty good. My electrical gage is so far off that it
never goes past the first bar -- that's probably part
of the reason why I gripe.
I think the PO did top end rebuild and I don't really care for
those. I run 15-40 in the winter and 20-50 in the summer
cause that's what all the smart people around here
recommend. According the Nick's formula, I'm doing
pretty good. My electrical gage is so far off that it
never goes past the first bar -- that's probably part
of the reason why I gripe.
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- #65
rgentry said:
Guess from what I found with this truck's engine and electrical oil pressure gauge compared to the mechanical that I had attached, your gauge would seem to be indicating similar to what I found....the first bar on this truck was right around 60 psi....it was less than the width of the needle past the first mark when it was at cold startup and warm high idle, and never less than the width of the needle to the low side of the first mark when at idle warm....
Poser said:Mark-
My statement about " wondering when this was going to start " was directed at the double entendre, not about you second-guessing me...
" a word or expression capable of two interpretations with one usually risqué "
I was surprised that there were not more crank comments...
I was surprised too.
I just wanted to be clear that *I* wasn't doing it. At least not this time on this operation.
I believe that you can find minimal acceptable oil pressure in the back of the FSM. IIRC it is surprisingly low. Lower than I can agree with.
The "10 psi per 1000 rpm" rule of thumb is based on chevy smallblocks. It may carry over to other engines, but it came to be from folks working on that engine specifically, not automotive engines in general.
Mark...
I have seen 1 bearing installed the wrong way and all the others installed correctly and it did not cause problems in the piston area. The end resault was 2-3 bad bearings and messed up crank. The fix was replace the bearings to next size and reground the crank since the crank had a really bad gouge.
Poser said:No, they were installed properly...ever seen a crank and bearing set that has had that happen to it??? Typically it not only takes out the bearing and the crank, but the block will need to be line bored as well....
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- #69
fjwagon said:
Line boring a block has nothing to do with the cylinders or pistons.
It is a process of machining the main bearing bores true again after a catastrophic bearing failure damages those areas in the cylinder block and the main bearing caps.
OK, I have a terminology question. I had my 2F bored .030 over and they wanted the main journals when they did it. For some reason I thought that was line boring. But I understand what you guys are saying about the mains being different sizes, so "line boring" is aligning all the journals.
Was what I had done to my block Align bored? It was supposed to make sure the cylinder was centered over the right spot on the crank for the con rod.
Just set me straight. Trying to learn something here.
Ed
Was what I had done to my block Align bored? It was supposed to make sure the cylinder was centered over the right spot on the crank for the con rod.
Just set me straight. Trying to learn something here.
Ed
Mark W said:You've misinterpeted the cause of you destroyed engine. A bearing can not "lock" sufficiently to do this. The bearings are too soft to instantly stop the rod rom rotating. They *will* "sieze". But that is basically melting due to insufficient lubrication. The result is a draging on the crank and a (relatively) gradual slow down. Once the rpm drops low enough the engine stalls out. A bearing can also "spin" (usually from excessive rpm) but again it is the bearing that is destroyed but it doesn't grenade the engine.. I have seen them melted from both of these type of failures to the point that they were extruded from the journal and sprayed around the crankcase. But a bearing failure will not cause the destruction of an engine at speed.
What is far more likely is that you over reved the engine, either as it came apart of not too long previously. This will stretch the rod bolts. Once this happens, the engine is just a littlebit of excitment waiting to happne.
This stretch relives the torque on the rod nuts and this will allow a rod nut to work loose and then it cascades from there. The other bolt gets stretched from the increased stress (if it wasn't already). The bolts bend and break, the cap comes off on the down strok, bounces off the pan, and winds up in the rotating assembly. At speed. THIS WILL cause the reults you describe.
I've seen this... a few times. At one time I had 4 engines here which had suffered this fate. Cool to look at if it's not your engine.
Mark...
I have certainly seen engines that wiped a bearing and were driven with a knock until the rod end cap was hammered off of the rod end, then the rod was smacked hard enough by the rotating crank journal to launch it through the block.
Got the rod and piston from one sitting on my file cabinet, in fact. It hit the cam so hard it busted it in four peices, which then became part of the rotating assembly as well.
Degnol said:OK, I have a terminology question. I had my 2F bored .030 over and they wanted the main journals when they did it. For some reason I thought that was line boring. But I understand what you guys are saying about the mains being different sizes, so "line boring" is aligning all the journals.
Was what I had done to my block Align bored? It was supposed to make sure the cylinder was centered over the right spot on the crank for the con rod.
Just set me straight. Trying to learn something here.
Ed
As you were told the main bearing journals are used to align the block. This is just cylinder boring. THere may e a way to do it without using the crank journals to line things up but if so, Ihaven't encountered it yet.
Mark...
Gumby said:
Yeah, I've seen this too. Not often, cause most people just can't abuse a motor that bad and that long. Kinda like kicking a kitten or ignoring a crying baby. It's tough to ignore that kind of banging for that long.
The "extruded berings that get melted and squeezed out come from doing this. Looks pretty cool when you open it up when the bearing is half gone from this.
But regardless, the final damage comes when things come apart, not from a bearing "locking up" and preventing the rod from rotating arond the crank and therefore causing the locked up rod to tear it's way through the block as the crank keeps turning
Mark....
The old man that did mine is in his late 60's early 70's and said the same thing...."not to many people are willing to do this".
Mark W said:I have yet to find a machinest who can line bore a 2F. Every main is a different size.
Mark...
Mark W said:
I don't know man, I went through it out of curiousity and the way that rod was frozen on the crank with it's piston, cylinder, and everything else shattered around it sure looked like it had done the deed. No doubt it wasn't getting adequate lube to turn 3,400 rpm. May be whatever was keeping it from getting lube migrated into the bearing and gave it the interfearance it needed. I have seen some engines that have been over sped come out of boats. I have also seen forced induction that forced too much, but this wasn't like the others.
I didn't miss that at all. It wouldn't take much more to drop the trans out of one of these, pull the timing off of it and get a look at the journals. Or at least pull the main caps and bearings off one or two at a time and spin it around to look. Suppose that this damage was caused by something that migrated through you oil system, where else did it go? How much of it was there? It's way easier now than when you get it back together and it has problems again. I'm not saying that it will, just cheap insurance to look at it now.Poser said:
Also, don't put me on the nay sayer list so quickly. My old man has done almost this same thing with an inline six on an old ford pick up when I was a kid. Didn't have a shop or a cherry picker, but could drop the trans on a floor jack and pulled the crank out. He honed the block without pulling it, reringed the pistons, dressed the crank a little with some emery cloth, lapped the valves in the dining room and then commensed to drive the truck a couple more years before selling it. The same guy tells me that, "if it ain't worth doin right, it ain't worth doin at all". He's been wrenching on cars for better than forty years already, so I take what your doing to be on the right list. Just not the best possible option in an ideal situation list.
Mark W said:I have yet to find a machinest who can line bore a 2F. Every main is a different size.
Mark...
Line boring is a wonderful thing. I have had EVERY engine I have rebuilt in my shop for the last 14 years line bored, and moved on to a new shop when the old shops said they couldn't get it done anymore.
My F135 in my lwb and my F155 in my 40 are both linebored, and I attribute a lot of the smoothness in both engines to it.
There are SOME advantages to living in a really big city!