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So, if i cant find a way to eliminate my big crank end play, i could end up putting in a new crank. Already took one Service able crank out of another engine. So now my question is: Will i be able to put it in from the bottom, without removing the top of engine at all. Cam is still in, lifters, intake, carburator also. (Engine is not in car, so dont worry))

Br, Henrik

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Maybe. The complete engine is about 550 lbs so you'll need a secure engine stand that rotates so the block is upside-down.  You'll need to slowly lower the crank while playing with each rod to maintain alignment as the crank is lowered, all without the rod bolts touching the rod journals and scarring them up. It'll be tricky. The bare crank weighs 53 lbs- I would use an engine hoist on the crank and pieces of plastic tubing on the rod bolts. Don't forget the crank seal halves. Good luck-

This is partially taken from 'Don Terrill's Speed Talk' online:

351 clev oversize thrust bearings

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forddan
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351 clev oversize thrust bearings

Post by forddan »

i cant find oversized "crank saver" thrust bearinging for 351 clev,does anybody know if you can use a 427 fe bearing as they list oversized bearings.seems the dimensions are the same,has anybody done this.
hondo383
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Re: 351 clev oversize thrust bearings

Post by hondo383 »

Yes just need to remove the locating tang.
BAracer
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Re: 351 clev oversize thrust bearings

Post by BAracer »

You can find .010" under with .010" wider thrust, and .020" wider thrust... I believe the last time I bought them for a customer in Australia, Don Gross Warehouse ordered them and I had them 2 days later. Don't remember which brand, but I think it was Clevite or King.
forddan
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Re: 351 clev oversize thrust bearings

Post by forddan »

thanks guys,i used king 427fe .020 oversize thrust,had to file half the tangs off and drill the cam oil feed hole.the only thing i did not like that they are full groove bearings.
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Re: 351 clev oversize thrust bearings

Post by jsgarage »

I went thru an exercise on this last year for someone trying to use a cut-down Windsor stroker crank in a 351-C, who was concerned about the larger OD Windsor thrust surface not being fully used on the crank by Cleveland bearings. You'll find that an FE bearing, while it can be made to work in a 351C, may be slightly smaller in dia. than an OEM 351C bearing. The width of the thrust surface is also smaller and varies from different bearing suppliers even for Cleveland stuff. If you have an ancient OEM bearing, measure it and start shopping, but most web sites that list bearings do not give the thrust ODs nor widths, so that's not much help. And NAPA & other big suppliers don't carry FE nor Cleveland stuff on the shelf; they have to order them. Here's what I found by going to a local old-time engine shop that had actual bearings on the shelf:

OEM 351C Bearing OD: 3.920" (TRW? Not sure)
Thrust surface width: 0.430"
Surface area: 4.72 sq. in.

ACL: FE thrust bearing OD: 3.915"
Thrust surface width: 0.414" (looks like there's a slightly larger chamfer at the crank)
Surface area: 4.53 sq. in. (96% of OEM)

You may get lucky and locate a bearing mfgr that makes a 351C or an FE bearing insert thats bigger in surface area than what I found. If you do, PM me. Since the thrust bearing surface is what takes manual clutch reaction force, an undersized bearing with a heavy clutch (plus some driver's habits) could maybe cause premature thrust bearing wear in some engines. During all this, another poster mentioned one can easily increase the oiling to the thrust surface by filing a tiny chamfer across the main bearing parting line- on one bearing half- and only from the oil groove to the 'clutch-in' side thrust surface. Extra oil not needed on the backside surface. Hope this helps.
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Re: 351 clev oversize thrust bearings

Post by russxr67 »

ACL make them in .010 oversize to suit the thrusts. They are readily available in Oz.
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It is going to be much easier to change the crank out of the engine if you remove it and put it on an engine stand. It is possible to do it in the car but with the amount of disassembly necessary, it is going to take a thousand times longer to do then just pulling it out and doing it the sane way.



For one thing, engine oil is going to be constantly dripping on your face and the bigger issue is that in order to drop the crank down, you need to disconnect the transmission from it.



Additionally, you are going to need to know the amount of thickness you need added to the bearing. To do that you need to pry the crank to measure the clearance that you have. Better to do that on the stand. I see it as likely you are going to need a custom thickness bearing and here's the issue, you can't know if for some reason, the thrust face of the crank is worn unevenly?

But even determining that, it is doing the entire thing backwards. Those bearings are likely to be made in some kind of standard oversizes which means that the crank is the thing that gets refinished, even on the thrust face.

Frankly, I think that it is all better to pull the engine and count on replacing the crankshaft.



Crank refinishers here only get like $150 on an exchange basis. If everything is stock, you won't even need to have the assembly rebalanced. Just change it out with new bearings that likely will be undersized.

In my racing days, no one wanted to use a crank with more then .020 over sized bearings. (If the crank is undersized then the bearing is oversized)

Correctly or incorrectly, the feeling was that because there was more metal in the bearings themselves, they were thicker, that it gave more possibility of essentially "squashing" the bearing. It is important to remember though that those engines were being turned at excessive rpm's so normally a .030 under crank with .030 over bearings, would never be an issue in street car. In a race engine, it might be.

I personally never saw that happen but who knows for sure? Maybe just racers paranoia?



I think that in the case of a Cleveland, fully grooved main bearings is an excellent precaution to build into the engine.

Last edited by panteradoug

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