My Willys 3A and 3B Community

3A, 3B, DJ Technical Knowledge Base => "Original"-- Technical Questions, Answers, Observations => Topic started by: athawk11 on September 25, 2013, 12:31:59 PM

Title: Late 3A Bell Housing Timing Hole
Post by: athawk11 on September 25, 2013, 12:31:59 PM
There is a very good discussion about re-timing an L-134 in an earlier thread.� It lead me to additional questions, but I didn't want to pirate that thread.

I went out last night and looked at a couple of the engines that are waiting for some love.� It was late, so I didn't get very far into it.�

Engine # 3J39316__ is an earlier 3A block that has the smaller flanges that don't cover the timing hole.� The bell housing is a late 3A.� There is no timing hole at all in the bell housing plate.� �

Did the timing hole in the plate completely disappear during later 3A production?

Tim
Title: Re: Late 3A Bell Housing Timing Hole
Post by: Ryan_M on September 25, 2013, 02:25:57 PM
Mine is a May '51 production 3A. As we all know from the previous thread my engine is later but I believe the bell housing plate is original. It has the timing hole.
Title: Re: Late 3A Bell Housing Timing Hole
Post by: SteveW on September 25, 2013, 03:15:26 PM
No mention at all of timing hole being done away with, just the reference that with larger starting motor and cylinder block flange beginning with 3a sn 130859 the hole was partially covered and couldn't be used for seeing timing marks, which were transferred to the timing gear cover. That thread about timing was very good indeed and I think I am 1 tooth off on my oil pump
Title: Re: Late 3A Bell Housing Timing Hole
Post by: 1955CJ-5 on September 25, 2013, 03:57:20 PM
My engine # is 3J-66559, and I believe it to be original to the 51 3A. Though the crank pulley has a notch, the marks are still on the flywheel and the hole is accessible. My flywheel only has two marks, TDC and 5 degrees. No IC or EC marks.

The timing cover was replaced during the rebuild so I don't know if it had any marks on it...one of these day's I'll get a chance to look though...
Title: Re: Late 3A Bell Housing Timing Hole
Post by: Bob W on September 26, 2013, 10:01:06 PM
The flywheel timing hole went away with the change to the later large rear flange engine casting.
Title: Re: Late 3A Bell Housing Timing Hole
Post by: athawk11 on September 27, 2013, 04:01:56 PM
Thanks Bob. 

I was hoping you were going to say that.  So, my understanding now is, for a short time, the late block with the larger flange was assembled with the bell housing plate with the timing hole.  But this went away fairly quickly.

Correct?

Tim
Title: Re: Late 3A Bell Housing Timing Hole
Post by: Bob W on September 27, 2013, 09:51:39 PM
Anything is possible but I don't think the rear plates with the timing window were used from the factory with the later large flange block. They had already begun using front pully timing marks before the change to the late block. There is some Willys service info explaining how to grind away part of the block flange when using a later replacement engine on an application with flywheel timing marks.