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Major problems, major stress

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lesingepsycho

Jedi Warrior
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How can I tell if I have a worn/wearing con-rod bearing without a complete tear-down?

I'm in a major pinch hear because I think I have a quickly wearing out #2 con-rod bearing but my Midget is my daily driver now, I have no backup and I'm fairly short on funds. Please tell me there's a solution. /bcforum/images/%%GRAEMLIN_URL%%/cry.gif

JACK
 
If you remove the pan and the suspect bearing look for a copper surface coming through the silver bearing material. If its looks good it may be the crank bearings. Generally one rod bearing failing leads to knocking when started and goes away when the oil pressure comes up. If you bring up the revs it will get louder even with good oil pressure.

Continuing to drive your car will gall the bearing and score the crankshaft. Then you get to tear the engine down and get the crank turned and have the piston rods sized and replace the bearings.

Also, the galled bearing material will start to migrate into other bearing areas and gall other internals (pistons, oil pump and cam bearings). This is how an engine destroys itself.

These are tough engines but cannot take much abuse before a rod takes a trip in the side of the block.

I hate to relay bad news but a lot of us have been in your position and it makes for a rough day.

Good Luck!
/bcforum/images/%%GRAEMLIN_URL%%/cheers.gif
 
I was afraid of that but not surprised. Hmmm, I'm going to have to reflect on this and devise a plan of action. Public transit is a possibility but not a particularly attractive one.

JACK
 
Drop the pan & crack the rod bearing open on a Friday night - if its the rod bearing, get a set from Steve at Northwest Imports on 10042 S.W. Balmer there in Portland...503.245.3806

....if you work with Steve before you break it open, telling him where you stand he might open on Saturday morning to sell you what you need....Steve's good people.....then you'd have Saturday & Sunday to get it back together.

Heck, while I was in there, I'd replace rods & main bearings.

(I may lose a potential customer here, but what's important is that you get your car on the road quickest.)
 
Bearings are so awful cheep I think I would have them on hand if I knew the sizes in advance??

And I know all of Miss Agathas sizes, wheeee.
 
Yeah, thanks Tony. Even if I have to go with the other guy in a pinch, there's still that other motor to rebuild down the line. Good customer relations today make for good customers tomorrow and your help will be remembered.

JACK
 
Donn you are just cheap the old fashioned way!! (me too!!) /bcforum/images/%%GRAEMLIN_URL%%/thumbsup.gif
 
Moss.

Rod bearings set 31 bucks.

Mains set 30 bucks

Thrust 12 bucks.

About the same as a full tank of gas in a regular car.
 
APTFAST

VPR91306-S..
Rod Bearings, 1275 With 1.75" Journals, Standard VP2
ST
$69.95


VPM91120-S..
Main Bearings, Cooper S, Late 1098 & 1275 pre-A+, Std
ST
$79.00

VPW41-S.....
Thrust Washers, 1275 & 1098 With 2.0" Mains, Standard
ST
$19.45

Not too bad
 
Let's get his car up & running for him first - quickly!!

Then, he can find another engine to build his way as he finds the extra cash!
 
lesingepsycho said:
I think I have a quickly wearing out #2 con-rod bearing
Click to expand...

Here's my question how do you know this, are you hearing a knock? If you're hearing a knock, here's the sad truth, a bearing will only buy you little time, if any at all, once you hear a knock, chances are the bearing has spun, there's a ton of debris in the oil, the crank is toast and a full rebuild is in order, plus probably a repalcement crankshaft. I know this is not what you want to hear.
My main curosity is to know what makes you think it's a rod bearing??????
 
Excellent point by Hap. Knocking usually means crankshaft is toast. But sometimes more time can be bought by polishing the crank in place with emery cloth, if the dimensions are not too far off. Technically not the right thing to do, but if the clearance remains within 0.005 or maybe up to 0.01, (I know that's a lot) it might run for quite a while if the journal is smooth and driven easy.
 
Well, right now it is just a bit of a knock, but not a loud knock, almost more like a tap or a sewing machine sound (tat, tat, tat, not like CLACK CLACK CLACK).

And on top of that, it doesn't knock all the time. It comes and goes seemingly dependant on oil temp and pressure although I haven't been able to sense a pattern.

It's soft enough that sometimes I think it might be in the valve train, but I readjusted the valves not long ago. I pulled compression and everything came up even. I haven't totally ruled out the rocker shaft assembly because I changed the assembly when I changed the head and I'm not sure the mount with the oil feed is in the correct position and I recall seeing a topic about how that can affect funny oil pressure readings and I guess therefore tapping (tappet) noises.

I feel that I should mention that the starter bendix jingles and I have something that is sort of a rattle/jingle coming from the trunk area that I haven't been able to locate so there are plenty of background noises that make it more difficult to pin-point this particular noise.

Bottom line: It's a mystery which is why I was asking HOW I would/could know if it was a con-rod bearing.

Thanks everybody, the input is really appreciated!

JACK
 
Jack

I remember that thread as well, I believe that it was to run the engine without the valve cover to make sure the rockers were getting their squirt.

Pat
 
Okay, I'm surprised nobody has suggested ~isolating~ this mysterious tap-tap-tap noise. Go find a stethoscope. One with a probe on it, start the beast, begin to poke around and find out just what part of the engine is tickin'. If the noise is stronger down low on the block, you have a good chance of spinning a bearing. If it's higher look to the valve train. It ~could~ even be a water pump failing (Tho they usually scream and leak).
 
Long thin screw driver held to ear and touched to block and around works in a pinch.
 
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