The only reason I asked this question in the first place was because a 3/8" UNF bolt screwed into all eight holes for a few threads and stopped. Because it was the same in all eight holes I did not want to force it. So, now I can run a 3/8 - 20 UNF tap through the hole to clean it up. So, I take it all threaded holes in the engine bay are UNF. Certainly simplifies it.<div id="yMail_cursorElementTracker_1589129381257">Mike MacLean<br><br><div id="ymail_android_signature"><a id="ymail_android_signature_link" href="https://go.onelink.me/107872968?pid=InProduct&c=Global_Internal_YGrowth_AndroidEmailSig__AndroidUsers&af_wl=ym&af_sub1=Internal&af_sub2=Global_YGrowth&af_sub3=EmailSignature">Sent from AT&T Yahoo Mail on Android</a></div> <br> <blockquote style="margin: 0 0 20px 0;"> <div style="font-family:Roboto, sans-serif; color:#6D00F6;"> <div>On Sun, May 10, 2020 at 8:51 AM, Curtis Arndt</div><div><cnaarndt@gmail.com> wrote:</div> </div> <div style="padding: 10px 0 0 20px; margin: 10px 0 0 0; border-left: 1px solid #6D00F6;"> <div id="yiv7438463404"><div>They are UNF on my BN1 built 11 Jan. '55. If they ever were BSF, it was very early in BN1 production. </div><br><div class="yiv7438463404gmail_quote"><div dir="ltr" class="yiv7438463404gmail_attr">On Sat, May 9, 2020, 16:54 Perry via Healeys <<a rel="nofollow" ymailto="mailto:healeys@autox.team.net" target="_blank" href="mailto:healeys@autox.team.net">healeys@autox.team.net</a>> wrote:<br></div><blockquote class="yiv7438463404gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;"><div lang="EN-US"><div class="yiv7438463404m_8389926694834509769WordSection1"><p class="yiv7438463404MsoNormal">Michael</p><p class="yiv7438463404MsoNormal">There was a slow switch from BSF to UNF fasteners used and threads on some parts starting about mid 1954 through the end of 1955 at several locations on the 100. However I can not speak to the engine mount to chassis fasteners. </p><p class="yiv7438463404MsoNormal">Its one of those areas of the car that if I ended up with damage to the welded nut threads that could not be cleaned up with a tap I would do what was necessary to secure the engine mount short of replacing the welded nut. </p><p class="yiv7438463404MsoNormal">Perry</p><p class="yiv7438463404MsoNormal"><u></u> <u></u></p><p class="yiv7438463404MsoNormal">Sent from <a rel="nofollow" target="_blank" href="https://go.microsoft.com/fwlink/?LinkId=550986">Mail</a> for Windows 10</p><p class="yiv7438463404MsoNormal"><u></u> <u></u></p><div style="border:none;border-top:solid #e1e1e1 1.0pt;padding:3.0pt 0in 0in 0in;"><p class="yiv7438463404MsoNormal" style="border:none;padding:0in;"><b>From: </b><a rel="nofollow" ymailto="mailto:rrengineer.mike@att.net" target="_blank" href="mailto:rrengineer.mike@att.net">Michael MacLean</a><br><b>Sent: </b>Saturday, May 9, 2020 5:14 PM<br><b>To: </b><a rel="nofollow" ymailto="mailto:healeys@autox.team.net" target="_blank" href="mailto:healeys@autox.team.net">Healeys</a><br><b>Subject: </b>[Healeys] Motor Mout Bolts</p></div><p class="yiv7438463404MsoNormal"><u></u> <u></u></p><p class="yiv7438463404MsoNormal">Are the bolts that fasten the motor mounts to the frame different threads between the BN1 and the BN2?<u></u><u></u></p><div id="yiv7438463404m_8389926694834509769yMail_cursorElementTracker_1589058832618"><p class="yiv7438463404MsoNormal" style="margin-bottom:12.0pt;">Mike MacLean<u></u><u></u></p></div><p class="yiv7438463404MsoNormal"><a rel="nofollow" target="_blank" href="https://go.onelink.me/107872968?pid=InProduct&c=Global_Internal_YGrowth_AndroidEmailSig__AndroidUsers&af_wl=ym&af_sub1=Internal&af_sub2=Global_YGrowth&af_sub3=EmailSignature">Sent from AT&T Yahoo Mail on Android</a></p><p class="yiv7438463404MsoNormal"><u></u> <u></u></p></div></div>_______________________________________________<br>
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