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Chain vs Gear Driven??

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captmec1 View Drop Down
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    Posted: 26 May 2016 at 3:40pm
Looking for some advise and conclusions on the much talked about topic, of chain driven vs gear driven. Question #1: I have a chain driven block, and gear driven parts (cam, crank, etc...), all rebuilt, BTW...oops.  I have been told that the main issue is the absence of the port for the timing gear oil jet. This along with other issues, it is impossible to "marry" the two together?  Question #2: Do i buy a gear driven block, or do I buy chain driven parts?  Remember, my block has been rebuilt, and all my parts are new.  Any direction on this, would be greatly appreciated.  As a side note, I don't necessarily care which set up i have, just trying to get a motor that works, and spend the least amount of money, the second time around.  Thanks.

Mark


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Post Options Post Options   Thanks (0) Thanks(0)   Quote athawk11 Quote  Post ReplyReply Direct Link To This Post Posted: 26 May 2016 at 4:12pm
Ouch.

Since you have a chain drive block all fixed up, I would build it...unless you can find a rebuilt gear block on the cheap.  I like both engines.  The chain stuff is clearly older, so in my humble opinion, it's cooler, and may have more value to some...if that makes any difference.

 Between the two styles, the biggest difference on the internals is the cam shaft and the oil pump gear.  They are not interchangeable.  The rest can be used in either block.  Additionally, you would need to track down timing chain and sprockets, a cover, and a couple other minor items for the front of the crank.  Maybe a spacer. (can't remember exactly)

Which front engine plate do you have?

1- 1946 CJ2A   
2- 1949 CJ3A
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captmec1 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote captmec1 Quote  Post ReplyReply Direct Link To This Post Posted: 26 May 2016 at 4:40pm
Thanks for the good info.  Seems to be a debate on the crank, interchangeable not interchangeable? The engine is in a 1952 M38, which I am learning, is not the right one.  Trying to track down serial numbers on engine.  They are cast on the bottom, below the distributor.  I have a gear driven timing cover.  
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athawk11 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote athawk11 Quote  Post ReplyReply Direct Link To This Post Posted: 26 May 2016 at 6:56pm
Well, there is a cut date for the cranks.  If memory serves, any crank newer than...sometime in 1948...will not have the oil passage for the sprocket, and shouldn't be used.  I'm sorry, I didn't mean to mislead.

When you say "The engine is in a 1952 M38..." Is this the gear drive parts donor? Or is this the chain drive block?
 
1- 1946 CJ2A   
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Mike S Quote  Post ReplyReply Direct Link To This Post Posted: 27 May 2016 at 1:27am
There is absolutely nothing wrong with the chain driven technology - most vehicles today use timing chains, right?

I replaced the gear drive engine in my '47 with a chain drive engine from a '46. I rebuilt everything and included a HD double roller chain. 
'47 CJ2A -- #114542
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captmec1 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote captmec1 Quote  Post ReplyReply Direct Link To This Post Posted: 27 May 2016 at 12:58pm
The timing chain motor was in the M38 when I bought it.  I believe the M38 had gear driven motor.  But, based on what I have, I believe I will be going with chain driven.  New crank, cam, oil pump and timing gears/chain seem to be better than finding and rebuilding new block.  I hate to waste all these shining new parts I have.  Will have a reground crank and cam, for anyone that is interested.

Mark

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Post Options Post Options   Thanks (0) Thanks(0)   Quote lebillco Quote  Post ReplyReply Direct Link To This Post Posted: 23 Mar. 2017 at 2:06pm
thanks for the membership, I'm trying to help a freind build his CJ engine.  He has 2 blocks, 1 gear 1 chain.  Can I use the chain block and install gear parts?  thank you for any suggestions you may offer.

lebillco
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cpt logger View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote cpt logger Quote  Post ReplyReply Direct Link To This Post Posted: 23 Mar. 2017 at 8:03pm
lebillco, First, welcome to the madness!

Second, it is best to start a new thread of your own for a change of subject like this. That way the next fellow who has the same question that you do, can find it with the advanced search feature.

Third, try the advanced search feature with this subject. I know that it has been addressed in the past. I just do not recall, off the top of my head, what is involved with that change.

IHTH, Cpt Logger.

PS. It can be done.


Edited by cpt logger - 23 Mar. 2017 at 8:05pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote tamnalan Quote  Post ReplyReply Direct Link To This Post Posted: 24 Mar. 2017 at 12:24pm
If you go with the chain motor, you should consider installing a Richard Sanders double roller chain.  A little spendy but it will last forever with good oil and your motor will love it.
Alan Johnson
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Adrian Quote  Post ReplyReply Direct Link To This Post Posted: 24 Mar. 2017 at 6:43pm
An Australian made roller chain kit was used when I rebuilt 14605's original engine, its a hell of lot better than a worn Morse Chain which the engine had originally.

If you can find a new Morse chain, its also an option, a badly worn one will make your Jeep sound like its diesel powered.
1946 CJ-2A Column Change 14605
1973 Saab 96
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Post Options Post Options   Thanks (0) Thanks(0)   Quote athawk11 Quote  Post ReplyReply Direct Link To This Post Posted: 24 Mar. 2017 at 8:07pm
Richard Saunders isn't making the Chain Roller kit anymore.  And it appears it's no longer offered at Ron Fitzpatrick's web site, so he may be out of them...for good.

You can use gear components in the chain drive block.  As illustrated in your photo, you will have to drill and tap for the cam retainer plate.  There may be a couple other minor things you'll need to address. 

Note: The camshaft and oil pump drive gear are NOT interchangeable between the gear drive engines and the chain drive engines.  All other engine parts are interchangeable between either style block.

Edit:  I only mention this because it looks like you have a chain drive cam in the chain drive block.  Don't try to use this with gear drive components.
   


Edited by athawk11 - 24 Mar. 2017 at 8:12pm
1- 1946 CJ2A   
2- 1949 CJ3A
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Post Options Post Options   Thanks (0) Thanks(0)   Quote WeeWilly Quote  Post ReplyReply Direct Link To This Post Posted: 24 Mar. 2017 at 9:04pm
The crankshaft for the chain drive also has a oil passage way bored to allow oil to the chain for the early system. You could plug it if using the early crank with a gear system to save a little oil pressure.

    Jim
47 CJ2A (Ranch Hand) 48 CJ2A, 48 Willys truck, T3C 3782, M274 (Military Mule)
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