Poser said:
So, what do you think caused this? A piece of flotsam between bearing and crank during installation/reassembly? You are making me skeerd about firing up my new motor, since I know the guy that put it back together...
Ed
Mains sticking to crank...
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So, what do you think caused this? A piece of flotsam between bearing and crank during installation/reassembly? You are making me skeerd about firing up my new motor, since I know the guy that put it back together...
Ed
- Thread starter
- #42
Ed-
I would not worry about your engine. People that are more cautious about things typically will fail on the side of not doing something, before doing it wrong. Your engine will be fine!
I have from day one, and still do today, get a bit tense about putting the flame to a new build; just that way I guess.
The issue with #4 bearing is from lack of oil pressure at low speed....something was in #2 and raised a bit of hell, but the crank is dressed, and I think that things will be fine. I need to verify that the oil pump is working properly before I put touch it off...but if it is, this should be good to go.
I would not worry about your engine. People that are more cautious about things typically will fail on the side of not doing something, before doing it wrong. Your engine will be fine!
I have from day one, and still do today, get a bit tense about putting the flame to a new build; just that way I guess.
The issue with #4 bearing is from lack of oil pressure at low speed....something was in #2 and raised a bit of hell, but the crank is dressed, and I think that things will be fine. I need to verify that the oil pump is working properly before I put touch it off...but if it is, this should be good to go.
Mark W
Yep, I really don't really care that much I guess.
I think that I'd probably skip the 240 grit myself and go straight to about 400 for a starting point. Having something that abrasive in my hand makes me nervous when I'm looking at a crank at the same time.
Sounds likeyou've done it before with positive results though.
Mark...
Sounds likeyou've done it before with positive results though.
Mark...
If I had one groove in one journal that I thought was over .010, I'd get it turned down. It's no big deal to take a few thou off with emory paper, but I think it's hard to stay even and make sure you are taking the right amount off all the way across when you are taking more. Plus with it this far disassemmbled, I hope you took the crank all the way out to inspect all of it thoroughly. You should at least measure the crank with a decent set of verniers. I had a bearing lock up in my F motor. The rod locked on tight enough that it became a fixed extension of the crank, and I was hauling ass. It shattered the piston, then the cylinder, the block on both sides, the cam, a couple of lifters, bent up the push rods. My oil pan looked like it had been shot at close range with a 3 3/4 inch 12 gauge 00 buck load. There was antique metal all over the highway. I'd hate to have that happen again, I don't cruise over 75 anymore either. But the ads from the day do say it can travel up to 85mph.
- Thread starter
- #46
40ozFJ said:
Guess you missed that this is inframe huh?
If the crank was really tore up on main journal, the engine would have come out....The fact that the journals were really not in that bad of condition makes me feel that I can roll in standard bearings, and that things will be fine. There is no significant signs of wear on the other bearings...even the rods are clean and not wore through the top tinning...you would think that since the bearing is significantly softer material compared to the crank, that the wear occuring would be to the bearing surface instead of the crankshaft....
But who knows.
When this thing lays down, all the nay-sayers can use this thread for all the reasons why you should not do this.
Good luck!
-Steve
Mark W
Yep, I really don't really care that much I guess.
Oh, I wasn't naysaying you. Just expressing a different judgement call. you were the one with the crank in front of you, not I.
Mark...
you were the one with the crank in front of you, not I.Mark...
Mark W
Yep, I really don't really care that much I guess.
40ozFJ 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...
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Steve, first time I've seen this thread since you called me on it.
Looking at the pics, there seems to be pretty strong evidence of contaminants in the oiling system that got pumped into #2 journal.
Which makes me wonder based on the flow patterns of the oiling system, if there isn't something still stuck in the passage between the rear of the oil galley and the #4 oiling journal.
I once saw a machine shop tap the oil galley to install threaded plugs and run the rear plug in far enough to cut flow to #4!
That was an expensive mistake on their part.
Might want to disconnect the oil pump and put an air line up to the block fitting and checking the airflow. Not very accurate, but certainly easier than removing the galley plugs.
Looking at the pics, there seems to be pretty strong evidence of contaminants in the oiling system that got pumped into #2 journal.
Which makes me wonder based on the flow patterns of the oiling system, if there isn't something still stuck in the passage between the rear of the oil galley and the #4 oiling journal.
I once saw a machine shop tap the oil galley to install threaded plugs and run the rear plug in far enough to cut flow to #4!
That was an expensive mistake on their part. Might want to disconnect the oil pump and put an air line up to the block fitting and checking the airflow. Not very accurate, but certainly easier than removing the galley plugs.
Mark W
Yep, I really don't really care that much I guess.
If you are concerned about this, the front plug could easily be accessed for removal and replacement. You could then apply air via the #4 oiling passge at the bearing while the plug is out. If there's anything in there it will be blown out the front. You could do this for each of the main bearing oiling ports. Probably *should* do all of them if you do it at all.
Mark...
Mark...
fjwagon
SILVER Star
Man I have seen that before, that bearing looked pretty bad. If the 40 was running normal and all of sudden this happened..... MY first thought would be a malfuntioned oil pump or you have some kind of blockage in the passage way where the damage bearing is located. Are sure they did not remove these bearings and installed them the wrong way a couple of days before this happened?? Just asking
Last edited:
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- #53
fjwagon said:Are sure they did not remove these bearings and installed them the wrong way a couple of days before this happened?? Just asking
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....
- Thread starter
- #54
Ok so I am a little late....
In picture one, this is a mechanical gauge tapped into the port where the sending unit would originally be, this is the oil pressure at startup, and 1800rpm's....15w40 engine oil....same stuff I run in all my junk year 'round....
The second pic is the oil pressure at idle after 20 minutes of operation at 1800 rpm's.
The third pic is the adapter fitting from -2, 1/8"-28 BSP to a -4 JIC male. There is then a 90 degree -4 JIC adapter connected to a hose going to the gauge.
In picture one, this is a mechanical gauge tapped into the port where the sending unit would originally be, this is the oil pressure at startup, and 1800rpm's....15w40 engine oil....same stuff I run in all my junk year 'round....
The second pic is the oil pressure at idle after 20 minutes of operation at 1800 rpm's.
The third pic is the adapter fitting from -2, 1/8"-28 BSP to a -4 JIC male. There is then a 90 degree -4 JIC adapter connected to a hose going to the gauge.
- Thread starter
- #55
So with this truck at least....
When the needle is on the first mark from the left on the stock oil pressure gauge, (effectively, right in the middle) it is reading right around 60 psi of oil pressure....
The engine has been running for a little over an hour or so, and seems to be fine. I am going to drop the oil and cut open the filter and see what, if anything is going on.
When the needle is on the first mark from the left on the stock oil pressure gauge, (effectively, right in the middle) it is reading right around 60 psi of oil pressure....
The engine has been running for a little over an hour or so, and seems to be fine. I am going to drop the oil and cut open the filter and see what, if anything is going on.
Adventure Teq
SILVER Star
You're just pluggin away at this. Seems to be good news.
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- #58
rgentry said:
" The second pic is the oil pressure at idle after 20 minutes of operation at 1800 rpm's. "
I would say that the engine was pleanty warm after running for 20 minutes at 1800 rpm...the second picture of the pressure gauge in post #54 is at idle...
- Thread starter
- #60
rgentry said:
What weight oil are you using? 10-30 or 40?? I can understand those #'s if it is one of them, or a synthetic.....
I really do not think that those numbers are all that bad....It is certianly not something that I would be losing my mind over.....You have stong oil pressure when the engine is at load, that is all you can ask for really....
Anyone know what min. oil pressure warm is? I have heard single digits...but cannot remember from who...
Good luck!
-Steve
