Timing Gears

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timjuhl
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Timing Gears

Post by timjuhl »

Any good advice for someone about to replace the timing gears in a F134 Hurricane Engine?

Actually, my mechanic is taking the lead on this one but he has never done a Hurricane and is trying to anticipate any problems before we start taking parts off.

Thanks!
Tim
Tim Juhl
1952 M38A1
1946 Aeronca L16A Army Liaison Aircraft
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wesk
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Post by wesk »

Just follow the book. Care with the fiber driven gear is important. Many cheaper aftermarket fiber gears are showing up with no timing mark. Also do NOT hammer gear on. Pull it on with the bolt and washer. If you hammer it on you will knock the rear cam bearing housing welsh plug loose and end up pulling the engine and flywheel to install a new one.

Image
Use correct puller.

Image
Establishing a timing mark on a blank timing gear.

Image
Cam welch plug
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

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timjuhl
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Gears

Post by timjuhl »

The gears are coming from NAPA so who knows? I assume from your post that the gear used on the M38 (pictured) is the same on the Hurricane in the M38A1.
Thanks again!
Tim
Tim Juhl
1952 M38A1
1946 Aeronca L16A Army Liaison Aircraft
southpw
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Re: Gears

Post by southpw »

timjuhl wrote:The gears are coming from NAPA so who knows? I assume from your post that the gear used on the M38 (pictured) is the same on the Hurricane in the M38A1.
Thanks again!
Tim
Yes Tim, same gears used on both engines. I just pulled those gears from an L and F head. I didnt have the right puller and broke the fiber gear into pieces. Then i couldnt get the remaining steel ring of the gear off the shaft. Much easier with proper puller. Luckily the F head was going to be sold in "as is" condition.
1952 M38 project
Brad
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timjuhl
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Timing gears

Post by timjuhl »

Any suggestions as to a good source for a replacement front crankshaft seal? I'm assuming it will require replacement as part of the gear replacement process.
Tim Juhl
1952 M38A1
1946 Aeronca L16A Army Liaison Aircraft
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wesk
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Post by wesk »

Your local Napa or Carquest or Bearing Store will have that front cover seal.

New VICTOR REINZ P/N: 49575

http://www.rockauto.com/en/moreinfo.php ... 21&jsn=389
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

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Post by GPA »

Tim, If you have done only the chain type, than don't worry because the gear type version is easier to do.
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timjuhl
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Timing Gears

Post by timjuhl »

It took most of the day but the new gears are in and the Jeep is back from the dead. The original phenolic gear was stamped Willys-Overland so it may well be over 60 years old. I compared the new steel gear to the original and decided to swap them out. The new gear has slightly beveled teeth and is polished smooth, while the original gear has pretty sharp edges.

I doubt the damage to the original phenolic gear happened all at once but finally got to the point where the teeth no longer engaged. Here is a photo comparing the old and new gears.

Tim
Image
Tim Juhl
1952 M38A1
1946 Aeronca L16A Army Liaison Aircraft
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Post by RICKG »

Don't toss that old gear Tim, dress it and re-purpose it as a hockey puck or paperweight!
keep 'em rollin'
RICKG MC 51986 DOD 01-52, '50 CJ3a
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timjuhl
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Timing gear

Post by timjuhl »

I plan to add it to my collection of "parts that seriously depleted my retirement account...."
Tim Juhl
1952 M38A1
1946 Aeronca L16A Army Liaison Aircraft
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timjuhl
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Timing Gear

Post by timjuhl »

I forgot to add that the gear I got from NAPA was marked "Made in USA" and had the timing dot. We simply lined the dots up and it worked!
Tim Juhl
1952 M38A1
1946 Aeronca L16A Army Liaison Aircraft
southpw
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Post by southpw »

I wish my local Napa could look up parts for my 52. If i dont have a modern part number for them to search, its useless going there. Too bad as i have found they are cheaper than buying from the USA and getting it shipped north of the border.
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Brad
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Post by 4x4M38 »

Brad,
Have them look up an early 1950's CJ3A.

Most of the engine, tranny and transfer
parts are interchangeable, except for the
military specific stuff.

Brian
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Post by 4x4M38 »

Here is a NAPA crossover list primarily
for the G503 WWII jeep, but many parts
are interchangeable. Not things like the
timing gears if course.

http://www.1943mb.com/np-66-0-G503_WWII ... nline.aspx

If I'm shopping NAPA I take the part with
me and compare with what they have. Or
will have. In most cases they'll have to
order what you need.

Then again, many if these parts are available
from our friendly neighborhood MV suppliers,
who in most cases have exactly what you need
once they know what you are putting it in.
southpw
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Post by southpw »

Thanks Brian. Napa Canada uses different part numbers. Ive tried giving them a US part number and they cant do anything with it. But here i could at least use the US number and try and cross reference myself to find the CDN part number.
I appreciate the link.
1952 M38 project
Brad
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