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Quick thoughts on bearings

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Well, I finally got around to starting my bearing replacement, been putting it off for weeks. Pulled the pan and the oil pump the other night and last night I did the rod bearings. Wasn't to bad, did all 6 in about an hour. I've got to wait for the dial indicator I ordered to come in before I can check the crank run out and do the mains and the thrust washers. I also ordered that steel replacement front engine sealing block from the guy on ebay, so I can't button it all back up until that comes in. Anyway, when I pulled the old rod bearings this is what I saw.

DSCN1893.jpg


Surfaces were worn down to the copper layer. My question is, is this typical wear or is something else going on here? I've read a few places that some other guys saw similar wear, but I don't recall the mileage they said they had on the motor at the time. The other 6 shells looked similar, some bad some not so bad. My old oil pump had a nice score in the outside rotor also. I heard all sorts of horror stories about the new pumps from Moss not being to good. I checked mine with a feeler gauge real quick and it looks OK.

Hopefully the gauge and sealing block will come soon and I can put this back together and move on to the rear hubs.
 
Hello Scott,
the shells don't look bad, in other words, normally worn out, have you some means of checking the journals' dimensions to see if they are in spec?
What about the main bearings? You can't measure that without removing the crank from the block although you will be able to see and feel if there is any significant wear as there will be a ridge around the oil drilling.

Alec
 
Hi Scott, It looks like you might not want to pull the crank shaft to check for wear, so another method of checking would be to place some plastigauge on each crankshaft journal install all your new bearings and torque your caps to spec then remove the cap and bearing and measure out the plastigauge to see how wide it had spread. this will then tell you how many thousands of wear you have on the crankshaft journal. You will have to look up the specs to see what is allowable wear.
 
The bearings look well worn but not abnormal. I think TR6's seem to be tuff on rod bearings. Many of the bearing shells have the name of the company and std or +.10 or other indication that would gicve you a clue as to size. If you are in a rush, I don't see any reason you could not mike the crank to see if it has been turned. I recognize that you would like to get the journal in the middle of the mic's jaws, but a nomial reading may answer your concerns.
 
Since you're going to do the mains anyway, mike them. The big ends don't look too bad, but the journals could be worn, oval or anything.

I think it's false economy not to take the crank out and do the job properly. You'll feel better about it afterwards, too.
 
Vrod, you hit it, I'd really like to avoid having to pull this motor and crank at this time. Basically the whole point of putting in the new bearings and pump is simply to address a low oil pressure issue thats been getting steadily worse. Other than that this motor runs fantastic and I haven't had any other problems with it since I did the head and carb rebuilds back when I bought the car, so I've really got no good reason to pull it yet. If I had uneven compression or was blowing oil then I'd consider a full rebuild, but right now I'd just like to get the pressure up and get another few years of fun driving out of it before I yank it and spend some serious bucks.

That being said, yes, I did plastigauged the rods when I put them in. I'm a little confused though what the max tolerance is for conrod clearance. The Bentley manual says something like .001-.0027", but this guy

Hottr6

is saying 0.0086-0.0125", which seems way to big to me. I'm consistently getting somewhere between .004 and .005 for them all, but I'm a bit worried this might be a little loose. ALso, I have no idea if any are out of round, but thats just a chance I'm going to have to take at this point. The old bearings didn't have any sizes on them, but they did have a marking that looked like a stylized V and P. The V was sort of like a triangle, with the P coming out of the right side of it. Any idea whats these are? There was also a number stamped next to this mark, 5105. There was another 6 digit number on the other side of the shell from these, but I forgot to write it down and can't remember it right now. I figure if the crank had ever been cut I'd have known it from the plastigauge, since I am using standard sized bearings. The readings would have been way off if it had been machined.

I will probably do the mains either tomorrow or Friday night. My dial indicator with magnetic base came today, so I should be good to check the crank play and the main journal runout. Nice piece, got it from Summit Racing for 30 bucks, I thought it was decent for the money. Might come in handy for looking at other stuff like brake disks, flywheels, etc.. I bought thrust washers from Moss in a few different sizes just in case. All I need now is the front sealing block.
 
Hey Roger....
Just replaced all my rod, main and thrust bearings last month.
Mine were on 52K miles and looked somewhat like yours but less worn. I would guess yours would be 70 to 80K miles?
My old bearings were VP 5105 also with no undersize markings and were standard size when I micrometered the journals.
I think that 4 to 5 thou clearance is a little on the large size but with new bearings should be ok for another 20K miles unless you're into redlining the RPM's then all bets are off. /ubbthreads/images/graemlins/shocked.gif
My oil pressure went up dramaticaly and now sits well over on the right hand side of the guage. /ubbthreads/images/graemlins/smile.gif
Make sure those thrust washers are installed the right way round.
 
The old bearings didn't have any sizes on them, but they did have a marking that looked like a stylized V and P. The V was sort of like a triangle, with the P coming out of the right side of it.

I'm just reading tea leaves here, but maybe thats really "AE". I just looked at an old rod bearing and it has marking like that (sort of). The bearings (and that symbol)is AE which is owned by Federal-Mogul.
All my undersize bearings (there have been many in this 1500!) are marked ".010" or whatever they are. If your's have no mark, they are probably standard.
The rod bearings you pulled look like normal but heavy wear (as others have said).
The .004 to .005 clearance on the new ones is worrisome to me. My latest are under .002 and over .003 would be cause for concern.
You can likely make them last for a while if you go easy on them, but I'd drop the pan after about 3000-4000 miles and check them again (and monitor oil pressure carefully in the meanwhile). Since you probably don't drive the car that much, maybe you can get a couple of years of easy use out of this, but in the long run you'll need a better fix.
Meanwhile, stay well below 4000 RPM as much as possible.
Having the crank reground and putting in all new bearings is not that expensive parts-wise (but the labor is a killer).
You can measure the end play (for thrust washers) with a feeler gauge, but that dial indicator is nicer (I have a similar one).
You need to buy a micrometer...you can find some acceptable ones at Enco:

https://www.use-enco.com

In the good old days, mechanics would "shim" the rod bearings with .001" brass stock to take up any play....acceptable (maybe) with a '37 Chevy, but even your Triumph is too modern for this "fix".

For future reference, a good source of reground cranks (for absolutely anything) is Storm Cranks in Mt. Vernon, NY (914-664-3563).
 
Hello Scott,

the second clearances you quote are certainly not bearing clearance, far too big, as you say. It could be end float clearance, however, of the connecting rods on the pins. The plastigauge measurements of the old bearing sound OK. You could use them twice if you want at 90degree points on each journal to get an ovality reading but really a micrometer is better.

Alec
 
Scott, the stylized VP is Vandervell's trademark.
Basil Adams, in Novato or thereabouts, may have some original Vandervell bearings. I'll look up his contact info when I get home from work, and PM it to you.
Jeff
 
Altaknight, wow, good guess. This motor has a little over 76K on it right now. I've got to go back and re-read the tolerances with plastigauge. I was using the largest size gauge, the blue stuff, which is for tolerances from .004 to .009 I think, so my readings might have been right at the reliable edge of what that size can do. The stuff was squished so thin I could see through it. I'm gonna pick up some of the red and green plastigauge on my way home today and see what I get with that.

I'm hoping a few of you are right. I don't put much mileage on this car per year, usually 1500 or less. I also don't hammer it. I like to drive it fast but I almost never rev it past 4K. Thats really not why I bought the car. If I want to go out and rip up the road I drive my buddies 400+hp Supra. However, the day comes I decide to start the frame off resto of this car I will be rebuilding the drivetrain with some hard driving in mind, but not right now. If I could get another 10K out of it I'd be happy, that would buy me probably close to 5 years the way I drive it now. Plenty of time to start thinking about a full blown rebuild.

Nial, I think jeff is right. I've seen the AE Federal Mogul symbol and I think this is different. I thought they might be Vandervell, I thought I read someplace that that was the brand Triumph used as OEM. Never seen this particular emblem before though, but I'm not real familiar with Vandervell. Never even heard of them before buying a British car. Federal Mogul is well known to me though, they are popular with the Ford and Chevy crowd. You're right, I need a micrometer. A micrometer is on my list of needed shop tools. Christmas present maybe.

I'll post some more info when I get the mains and thrust washers out. For thrust washer alignment I've read that the easy way to remember it is that the grooves must face away from each other, outward from the crank journal.
 
Hello Scott,

I don't know if Vandervell bearings are available in America but they are a good quality bearing.
Going back to the mid fities, Tony Vandervell, an english industrialist won the world Formula One constructors championship with his Vanwall car, part designed by Colin Chapman and Frank Costin.


Alec
 
Good call, Jeff.
I was curious and found the company logo. Apparently, Vandervell is now owned by Dana Corp (they also make Clevite bearings).

Yes, Scott...get some "skinny" Plastigage and see if things look any better.

Like Alec, I recall the Vanwall front-engine F1 cars of the 50's, but I had forgotten their connection to Vandervell.

Speaking of bearings, I helped a friend install a crank in a 1.8 VW motor (20 valve) a while back, and it had no locating notches on the bearings. The "crush" of the caps hold the bearing inserts in place. This is a new one on me.

Lta.gif
 
OK, I re-read the rod clearances using a more appropriately sized plastigauge. I got fairly consistent readings again, right around .003". This is at least right near the high end of the tolerance. HAHA, nothing like testing into compliance as we say in analytical chemistry. If your first analysis fails, just keep running it until it passes. Hopefully thats not the case here.
 
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