Tappet clearnace on TC (1949)

[Norman Verona]

Bill,

 

New timing chain, timing wheels & tensioner, new cam followers, the clatter is definitely from the tappets. I m pretty sure the camshaft is original as it hasn t been changed the mid 1950 s. I doubt it would have been changed in its first 6 or 7 years on the road.

 

 

[b][i]Norman Verona[/i][/b]

11 Cherry Close, Royston, South Yorkshire S71 4LZ

Phone: 0044 (0)1226 728811

Mob: 0044 (0)741 9905 741

[b][i]Web: www.frenchblat.com[/i][/b]

 

[b]From:[/b] Bill Hyatt [mailto:usaj24@earthlink.net] [b]Sent:[/b] 18 February 2018 14:05 [b]To:[/b] Norman Verona norman@frenchblat.com> [b]Cc:[/b] David James dr.david.james@gmail.com>; mg-tabc@yahoogroups.com [b]Subject:[/b] Re: [mg-tabc] Re: Tappet clearnace on TC (1949)

 

Guys, 

Clatter can also come from timing chain tensioner as it translates back and forth axially

-Bill Hyatt

Sent from my iPhone

On Feb 18, 2018, at 6:01 AM, 'Norman Verona' norman@frenchblat.com [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote:

 

David,

 

My clatter is from the tappets. The tappet faces are good (I ve fully rebuilt the engine) As far as I know it s a 0.017 camshaft.

 

I ll try reducing them to m0.015 and if the clatter is the same open them back up to 0.017 .

 

I don t over rev the engine, 4000 rpm is about as high as I take it. It s as standard as it can be apart from 0.040 oversize pistons from a rebore before I bought the car.

 

I don t need speed from this car, I have a manic Caterham with 220 BHP weighing 500 kgs. That s for the time I want to shake some cobwebs. Also my everyday car is a 189 bhp Lotus Elise. The TC is for driving sedately along country roads.

 

 

[b][i]Norman Verona[/i][/b]

11 Cherry Close, Royston, South Yorkshire S71 4LZ

Phone: 0044 (0)1226 728811

Mob: 0044 (0)741 9905 741

[b][i]Web: www.frenchblat.com[/i][/b]

 

[b]From:[/b] mg-tabc@yahoogroups.com [mg-tabc@yahoogroups.com] [b]On Behalf Of [/b]David James dr.david.james@gmail.com [mg-tabc] [b]Sent:[/b] 18 February 2018 10:10 [b]To:[/b] mg-tabc@yahoogroups.com [b]Subject:[/b] [mg-tabc] Re: Tappet clearnace on TC (1949)

 

 

I had noticed play in the distributor shaft of my 1948 TC, along with quite a lot of oil in the distributor top, and thought this might be the cause of the noisy engine. So I replaced the bushes in the distributor body. This cured the oil problem, but not the clatter. So I used the method given on the MGCC Y-Type Register web site to determine that the camshaft was still of the type that required a 19thou tappet clearance. On the basis that there are indents on the rockers that my feeler gauge would not detect, I set the clearance to 17thou. It is still noisy, but I am reluctant to reduce the clearance further. David (TC4985)

[Tweed]

Hi Norman, I too hate clattery tappets and have those on TC 0632 set at 0.015".    I have a friend with a beautiful TD which he runs with 0.019" as stated on the oval plate on the 'bread bin' .... but you can hear him coming a mile away!  TweedTC 0632  ....   running sweet as nut with 0.015"Cambridge UK  From: "norman@frenchblat.com [mg-tabc]" mg-tabc-noreply@yahoogroups.com> [b]To:[/b] mg-tabc@yahoogroups.com [b]Sent:[/b] Saturday, 17 February 2018, 21:21 [b]Subject:[/b] [mg-tabc] Tappet clearnace on TC (1949)   I'm sorry to bring this up again, I'm sure it was discussed some time ago. But my memory isn't what it used to be. What's the thinking of setting the tappets to 0.015" instead of 0.017" to stop the clatter.  I really hate valve clatter as it sounds like a poorly maintained engine. If the group thinks it's OK I'll set them to 15 thou whilst I have it in the workshop. Thanks, Norman VeronaTC10178 #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655 -- #ygrps-yiv-447589695yiv9925991655ygrp-mkp { border:1px solid #d8d8d8;font-family:Arial;margin:10px 0;padding:0 10px;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655ygrp-mkp hr { border:1px solid #d8d8d8;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655ygrp-mkp #ygrps-yiv-447589695yiv9925991655hd { color:#628c2a;font-size:85%;font-weight:700;line-height:122%;margin:10px 0;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655ygrp-mkp #ygrps-yiv-447589695yiv9925991655ads { margin-bottom:10px;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655ygrp-mkp .ygrps-yiv-447589695yiv9925991655ad { padding:0 0;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655ygrp-mkp .ygrps-yiv-447589695yiv9925991655ad p { margin:0;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655ygrp-mkp .ygrps-yiv-447589695yiv9925991655ad a { color:#0000ff;text-decoration:none;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655ygrp-sponsor #ygrps-yiv-447589695yiv9925991655ygrp-lc { font-family:Arial;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655ygrp-sponsor #ygrps-yiv-447589695yiv9925991655ygrp-lc #ygrps-yiv-447589695yiv9925991655hd { margin:10px 0px;font-weight:700;font-size:78%;line-height:122%;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655ygrp-sponsor #ygrps-yiv-447589695yiv9925991655ygrp-lc .ygrps-yiv-447589695yiv9925991655ad { margin-bottom:10px;padding:0 0;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655actions { font-family:Verdana;font-size:11px;padding:10px 0;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655activity { background-color:#e0ecee;float:left;font-family:Verdana;font-size:10px;padding:10px;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655activity span { font-weight:700;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655activity span:first-child { text-transform:uppercase;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655activity span a { color:#5085b6;text-decoration:none;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655activity span span { color:#ff7900;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655activity span .ygrps-yiv-447589695yiv9925991655underline { text-decoration:underline;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 .ygrps-yiv-447589695yiv9925991655attach { clear:both;display:table;font-family:Arial;font-size:12px;padding:10px 0;width:400px;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 .ygrps-yiv-447589695yiv9925991655attach div a { text-decoration:none;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 .ygrps-yiv-447589695yiv9925991655attach img { border:none;padding-right:5px;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 .ygrps-yiv-447589695yiv9925991655attach label { display:block;margin-bottom:5px;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 .ygrps-yiv-447589695yiv9925991655attach label a { text-decoration:none;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 blockquote { margin:0 0 0 4px;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 .ygrps-yiv-447589695yiv9925991655bold { font-family:Arial;font-size:13px;font-weight:700;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 .ygrps-yiv-447589695yiv9925991655bold a { text-decoration:none;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 dd.ygrps-yiv-447589695yiv9925991655last p a { font-family:Verdana;font-weight:700;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 dd.ygrps-yiv-447589695yiv9925991655last p span { margin-right:10px;font-family:Verdana;font-weight:700;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 dd.ygrps-yiv-447589695yiv9925991655last p span.ygrps-yiv-447589695yiv9925991655yshortcuts { margin-right:0;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 div.ygrps-yiv-447589695yiv9925991655attach-table div div a { text-decoration:none;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 div.ygrps-yiv-447589695yiv9925991655attach-table { width:400px;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 div.ygrps-yiv-447589695yiv9925991655file-title a, #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 div.ygrps-yiv-447589695yiv9925991655file-title a:active, #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 div.ygrps-yiv-447589695yiv9925991655file-title a:hover, #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 div.ygrps-yiv-447589695yiv9925991655file-title a:visited { text-decoration:none;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 div.ygrps-yiv-447589695yiv9925991655photo-title a, #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 div.ygrps-yiv-447589695yiv9925991655photo-title a:active, #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 div.ygrps-yiv-447589695yiv9925991655photo-title a:hover, #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 div.ygrps-yiv-447589695yiv9925991655photo-title a:visited { text-decoration:none;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 div#ygrps-yiv-447589695yiv9925991655ygrp-mlmsg #ygrps-yiv-447589695yiv9925991655ygrp-msg p a span.ygrps-yiv-447589695yiv9925991655yshortcuts { font-family:Verdana;font-size:10px;font-weight:normal;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 .ygrps-yiv-447589695yiv9925991655green { color:#628c2a;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 .ygrps-yiv-447589695yiv9925991655MsoNormal { margin:0 0 0 0;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 o { font-size:0;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655photos div { float:left;width:72px;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655photos div div { border:1px solid #666666;min-height:62px;overflow:hidden;width:62px;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655photos div label { color:#666666;font-size:10px;overflow:hidden;text-align:center;white-space:nowrap;width:64px;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655reco-category { font-size:77%;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655reco-desc { font-size:77%;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 .ygrps-yiv-447589695yiv9925991655replbq { margin:4px;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655ygrp-actbar div a:first-child { margin-right:2px;padding-right:5px;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655ygrp-mlmsg { font-size:13px;font-family:Arial, helvetica, clean, sans-serif;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655ygrp-mlmsg table { font-size:inherit;font:100%;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655ygrp-mlmsg select, #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 input, #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 textarea { font:99% Arial, Helvetica, clean, sans-serif;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655ygrp-mlmsg pre, #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 code { font:115% monospace;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655ygrp-mlmsg * { line-height:1.22em;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655ygrp-mlmsg #ygrps-yiv-447589695yiv9925991655logo { padding-bottom:10px;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655ygrp-msg p a { font-family:Verdana;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655ygrp-msg p#ygrps-yiv-447589695yiv9925991655attach-count span { color:#1E66AE;font-weight:700;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655ygrp-reco #ygrps-yiv-447589695yiv9925991655reco-head { color:#ff7900;font-weight:700;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655ygrp-reco { margin-bottom:20px;padding:0px;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655ygrp-sponsor #ygrps-yiv-447589695yiv9925991655ov li a { font-size:130%;text-decoration:none;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655ygrp-sponsor #ygrps-yiv-447589695yiv9925991655ov li { font-size:77%;list-style-type:square;padding:6px 0;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655ygrp-sponsor #ygrps-yiv-447589695yiv9925991655ov ul { margin:0;padding:0 0 0 8px;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655ygrp-text { font-family:Georgia;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655ygrp-text p { margin:0 0 1em 0;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655ygrp-text tt { font-size:120%;} #ygrps-yiv-447589695 #ygrps-yiv-447589695yiv9925991655 #ygrps-yiv-447589695yiv9925991655ygrp-vital ul li:last-child { border-right:none !important;} #ygrps-yiv-447589695

[Norman Verona]

David, The original camshaft had no wear and the bearings were fine so I left them in. If it ain't broke, don't fix it. Sent from BlueMail On Feb 19, 2018, at 9:04 AM, "David Wardell dwardell@talktalk.net [mg-tabc]" mg-tabc-noreply@yahoogroups.com> wrote: The true answer to your query Norman is ... it all depends. I presume you put in a new camshaft when you rebuilt the engine and the grind would (probably) be different from the original TC XPAG grind. And the camshaft supplier would have specified the rocker clearance. A lot of newer camshafts, including those originally fitted to later TDs, specified 12 thou clearance and this figure is quite common for a number of different camshafts available. However ... I got quite a surprise when B&G fitted their fast road cam to my XPEG: the spec for the clearance for that is 18 thou inlet, 20 thou exhaust ... I ve got used to the noise and cam is great. David

[Robert FzMG]

Norman - it s also possible for the face of the rocker arm to be slightly worn from contact with the top of the valve.  This will result in an inaccurate measurement with a feeler gauge, because the gauge blade will mask the worn face. Best regards,  Robert TC9851, TA2692 San Jose, California

On Feb 18, 2018, at 6:30 AM, 'Norman Verona' norman@frenchblat.com [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote: Bill,

 

New timing chain, timing wheels & tensioner, new cam followers, the clatter is definitely from the tappets. I m pretty sure the camshaft is original as it hasn t been changed the mid 1950 s. I doubt it would have been changed in its first 6 or 7 years on the road.

 

 

Norman Verona

11 Cherry Close, Royston, South Yorkshire S71 4LZ

Phone: 0044 (0)1226 728811

Mob: 0044 (0)741 9905 741

Web: www.frenchblat.com

 

From: Bill Hyatt [usaj24@earthlink.net]  Sent: 18 February 2018 14:05 To: Norman Verona norman@frenchblat.com> Cc: David James dr.david.james@gmail.com>; mg-tabc@yahoogroups.com Subject: Re: [mg-tabc] Re: Tappet clearnace on TC (1949)

 

Guys, 

Clatter can also come from timing chain tensioner as it translates back and forth axially

-Bill Hyatt

Sent from my iPhone

On Feb 18, 2018, at 6:01 AM, 'Norman Verona' norman@frenchblat.com [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote:

  

David,

 

My clatter is from the tappets. The tappet faces are good (I ve fully rebuilt the engine) As far as I know it s a 0.017 camshaft.

 

I ll try reducing them to m0.015 and if the clatter is the same open them back up to 0.017 .

 

I don t over rev the engine, 4000 rpm is about as high as I take it. It s as standard as it can be apart from 0.040 oversize pistons from a rebore before I bought the car.

 

I don t need speed from this car, I have a manic Caterham with 220 BHP weighing 500 kgs. That s for the time I want to shake some cobwebs. Also my everyday car is a 189 bhp Lotus Elise. The TC is for driving sedately along country roads.

 

 

Norman Verona

11 Cherry Close, Royston, South Yorkshire S71 4LZ

Phone: 0044 (0)1226 728811

Mob: 0044 (0)741 9905 741

Web: www.frenchblat.com

 

From: mg-tabc@yahoogroups.com [mg-tabc@yahoogroups.com] On Behalf Of David James dr.david.james@gmail.com [mg-tabc] Sent: 18 February 2018 10:10 To: mg-tabc@yahoogroups.com Subject: [mg-tabc] Re: Tappet clearnace on TC (1949)

 

  

I had noticed play in the distributor shaft of my 1948 TC, along with quite a lot of oil in the distributor top, and thought this might be the cause of the noisy engine. So I replaced the bushes in the distributor body. This cured the oil problem, but not the clatter. So I used the method given on the MGCC Y-Type Register web site to determine that the camshaft was still of the type that required a 19thou tappet clearance. On the basis that there are indents on the rockers that my feeler gauge would not detect, I set the clearance to 17thou. It is still noisy, but I am reluctant to reduce the clearance further. David (TC4985)

[Norman Verona]

Robert,

 

No, the faces are fine, I faced them with a wet stone. They were hardly worn anyway. The car had only done a genuine 98,000 miles when I rebuilt it in 2015. That may sound al lot but not for a 66 year old car,

 

 

[b][i]Norman Verona[/i][/b]

11 Cherry Close, Royston, South Yorkshire S71 4LZ

Phone: 0044 (0)1226 728811

Mob: 0044 (0)741 9905 741

[b][i]Web: www.frenchblat.com[/i][/b]

 

[b]From:[/b] Robert FzMG [mailto:robfzmg@outlook.com] [b]Sent:[/b] 21 February 2018 03:41 [b]To:[/b] Norman Verona norman@frenchblat.com> [b]Cc:[/b] Bill Hyatt usaj24@earthlink.net>; David James dr.david.james@gmail.com>; mg-tabc@yahoogroups.com [b]Subject:[/b] Re: [mg-tabc] Tappet clearnace on TC (1949)

 

Norman - it s also possible for the face of the rocker arm to be slightly worn from contact with the top of the valve.  This will result in an inaccurate measurement with a feeler gauge, because the gauge blade will mask the worn face.

 

Best regards, 

 

Robert

 

TC9851, TA2692

San Jose, California

On Feb 18, 2018, at 6:30 AM, 'Norman Verona' norman@frenchblat.com [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote:

 

 

Bill,

 

New timing chain, timing wheels & tensioner, new cam followers, the clatter is definitely from the tappets. I m pretty sure the camshaft is original as it hasn t been changed the mid 1950 s. I doubt it would have been changed in its first 6 or 7 years on the road.

 

 

[b][i]Norman Verona[/i][/b]

11 Cherry Close, Royston, South Yorkshire S71 4LZ

Phone: 0044 (0)1226 728811

Mob: 0044 (0)741 9905 741

[b][i]Web: www.frenchblat.com[/i][/b]

 

[b]From:[/b] Bill Hyatt [usaj24@earthlink.net]  [b]Sent:[/b] 18 February 2018 14:05 [b]To:[/b] Norman Verona norman@frenchblat.com> [b]Cc:[/b] David James dr.david.james@gmail.com>; mg-tabc@yahoogroups.com [b]Subject:[/b] Re: [mg-tabc] Re: Tappet clearnace on TC (1949)

 

Guys, 

Clatter can also come from timing chain tensioner as it translates back and forth axially

-Bill Hyatt

Sent from my iPhone

On Feb 18, 2018, at 6:01 AM, 'Norman Verona' norman@frenchblat.com [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote:

  

David,

 

My clatter is from the tappets. The tappet faces are good (I ve fully rebuilt the engine) As far as I know it s a 0.017 camshaft.

 

I ll try reducing them to m0.015 and if the clatter is the same open them back up to 0.017 .

 

I don t over rev the engine, 4000 rpm is about as high as I take it. It s as standard as it can be apart from 0.040 oversize pistons from a rebore before I bought the car.

 

I don t need speed from this car, I have a manic Caterham with 220 BHP weighing 500 kgs. That s for the time I want to shake some cobwebs. Also my everyday car is a 189 bhp Lotus Elise. The TC is for driving sedately along country roads.

 

 

[b][i]Norman Verona[/i][/b]

11 Cherry Close, Royston, South Yorkshire S71 4LZ

Phone: 0044 (0)1226 728811

Mob: 0044 (0)741 9905 741

[b][i]Web: www.frenchblat.com[/i][/b]

 

[b]From:[/b] mg-tabc@yahoogroups.com [mg-tabc@yahoogroups.com] [b]On Behalf Of [/b]David James dr.david.james@gmail.com [mg-tabc] [b]Sent:[/b] 18 February 2018 10:10 [b]To:[/b] mg-tabc@yahoogroups.com [b]Subject:[/b] [mg-tabc] Re: Tappet clearnace on TC (1949)

 

  

I had noticed play in the distributor shaft of my 1948 TC, along with quite a lot of oil in the distributor top, and thought this might be the cause of the noisy engine. So I replaced the bushes in the distributor body. This cured the oil problem, but not the clatter. So I used the method given on the MGCC Y-Type Register web site to determine that the camshaft was still of the type that required a 19thou tappet clearance. On the basis that there are indents on the rockers that my feeler gauge would not detect, I set the clearance to 17thou. It is still noisy, but I am reluctant to reduce the clearance further. David (TC4985)

 

 

[Roger Bateman]

Hi Norman, Me again! I hesitate to offer advice to a man who served his apprenticeship on T Types, but I would like to go back to the fact that you mentioned that your engine had been rebored to +.040 at what today we think of as a low mileage, but then, with poorer oils and maybe a lack of oil changes, was fairly normal. Boring out to that for the first time means the engine must have been pretty tired. It is a major overhaul and the block would probably have been stripped out. Well, if the bores were that worn, isn t it feasible that the (known to wear badly) camshaft was also found to be worn out and was changed for a .012 type during that overhaul? I know you said you have the history, but it s possible for the odd bit of info to be lost over time, or not recorded as not appearing important? Might not the factory have supplied a replacement under some sort of warranty, so there wouldn t be an invoice? I would suggest you do the checks referred to in my last reply to determine which camshaft you have, and also set the valve clearances with a DTI to eliminate the possibility of any wear in the valve train. Then you can be sure that any noise is normal. Roger Bateman TC2456 Dorset UK

[Clive Sherriff]

Norman, NEVER, but NEVER make assumptions. If your engine had so much wear that it needed rebores up to 0.040 before you bought it, I'd say it might well have needed, and had, a new cam too. TRY THIS, note uin last paragraph " [b] An engine equipped with AAA3096, but with the clearance met at 0.019 in. will be slightly down on power and will produce a really awful amount of valve clatter"[/b] [b]So:-[/b][b] [/b][b]Camshaft - Determination Two different camshafts were supplied as original equipment for the XPAG and XPEG engines. The earliest type, part number AAA5776 (earlier numbers MG862/171 or X24084), was used in all TB and TC engines, and in TD engines up to engine number XPAG/TD2/24l15. This early cam requires a valve clearance of 0.019 in. [/b] [b] [/b]

[b]The later type, part number AAA3096 (earlier number 168553) was used in all later TD and TF engines and requires a valve clearance of 0.012 in. Unfortunately, now that even the newest TF is almost 40 years old, the engine numbers quoted above are not necessarily a valid guide for purpose of camshaft identification. Engines originally equipped with AAA5776 may have been fitted with AAA3096 in the course of an overhaul. [/b]

[b] [/b]

[b]With the engine cold, remove the rocker cover and turn the engine over with the crank until #1 intake valve (2nd valve from front of engine) is wide open. At this point, #4 intake valve (7th from front) will be fully closed and on the exact center of the heel of the cam lobe. Set #4 intake to 0.021 in. clearance. This is the correct checking clearance for both cams, regardless of whether you use the degree wheel and dial indicator method or the simplified method which follows. Now, wipe all the accumulated gook off the crankshaft pulley, and get out your measuring tape and a piece of chalk. Measuring around the rim of the pulley. make one chalk mark between 1/32 in. and 3/64 in. to the right (as seen from the front) of the top dead centre mark on the pulley. This corresponds to 5 BTDC, which is when the intake opens on the later cam (AAA3096). [/b]

[b] [/b]

[b]Make a second chalk mark 23/64 in. to the right of the TDC mark. This corresponds to 11 BTDC, which is when the intake opens on the earlier cam (AAA5776). Next, turn the engine over with the crank (it's easier with the spark plugs out) until the pushrod for #4 intake valve just barely locks up enough so that you can't spin it between your fingers. At this point, the timing pointer on the timing chain cover should be more or less aligned with one or the other of the chalk marks. [/b]

[b] [/b]

[b]If the pointer aligns with the 11 mark, then you have the early cam (AAA5776) and you should set the valve clearance to 0.019 in. with the engine hot. If the pointer aligns with the 5 mark then you have the later cam (AAA3096) and you should set the valve clearance to 0.012 in. hot. If the pointer does not align with either mark, go back through the entire procedure again to make sure you did it right. [/b]

[b] [/b]

[b]What effect does the wrong valve clearance setting have on the engine? This is a bit difficult for the novice to pinpoint unless he can compare performance to a properly set up car. In general, however, an engine equipped with AAA5776, but with the valve clearance set at 0.012 in. will be very low on power. An engine equipped with AAA3096, but with the clearance met at 0.019 in. will be slightly down on power and will produce a really awful amount of valve clatter. You should also bear in mind the fact that while clearance which is too large is noisy, it doesn't necessarily produce any mechanical damage. On the other hand, burnt exhaust valves will almost surely result from unduly small valve clearance, as in the case of an AAA5776 cam set at 0.012 in.[/b]

[b] [/b]

Clive, Oxford, UK [img]https://ec.yimg.com/ec?url=https%3A%2F%2Fipmcdn.avast.com%2Fimages%2Ficons%2Ficon-envelope-tick-round-orange-animated-no-repeat-v1.gif&t=1522512019&sig=dzpPSSRgAQ8Ky8KK5ft6Eg--~D[/img] Virus-free. www.avast.com

On Sun, Feb 18, 2018 at 2:30 PM, 'Norman Verona' norman@frenchblat.com [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote: [u][/u] Bill,[u][/u][u][/u][u][/u] [u][/u]

New timing chain, timing wheels & tensioner, new cam followers, the clatter is definitely from the tappets. I m pretty sure the camshaft is original as it hasn t been changed the mid 1950 s. I doubt it would have been changed in its first 6 or 7 years on the road.[u][/u][u][/u]

[u][/u] [u][/u]

[u][/u] [u][/u]

[b][i]Norman Verona[u][/u][u][/u][/i][/b]

11 Cherry Close, Royston, South Yorkshire S71 4LZ[u][/u][u][/u]

Phone: 0044 (0)1226 728811[u][/u][u][/u]

Mob: 0044 (0)741 9905 741[u][/u][u][/u]

[b][i]Web: www.frenchblat.com[u][/u][u][/u][/i][/b]

[u][/u] [u][/u]

[b]From:[/b] Bill Hyatt [mailto:usaj24@earthlink.net] [b]Sent:[/b] 18 February 2018 14:05 [b]To:[/b] Norman Verona norman@frenchblat.com> [b]Cc:[/b] David James dr.david.james@gmail.com>; mg-tabc@yahoogroups.com [b]Subject:[/b] Re: [mg-tabc] Re: Tappet clearnace on TC (1949)[u][/u][u][/u]

[u][/u] [u][/u]

Guys, [u][/u][u][/u]

Clatter can also come from timing chain tensioner as it translates back and forth axially[u][/u][u][/u]

-Bill Hyatt[u][/u][u][/u]

Sent from my iPhone[u][/u][u][/u]

On Feb 18, 2018, at 6:01 AM, 'Norman Verona' norman@frenchblat.com [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote:[u][/u][u][/u]

[u][/u][u][/u]

David,[u][/u][u][/u]

[u][/u][u][/u]

My clatter is from the tappets. The tappet faces are good (I ve fully rebuilt the engine) As far as I know it s a 0.017 camshaft.[u][/u][u][/u]

[u][/u][u][/u]

I ll try reducing them to m0.015 and if the clatter is the same open them back up to 0.017 .[u][/u][u][/u]

[u][/u][u][/u]

I don t over rev the engine, 4000 rpm is about as high as I take it. It s as standard as it can be apart from 0.040 oversize pistons from a rebore before I bought the car.[u][/u][u][/u]

[u][/u][u][/u]

I don t need speed from this car, I have a manic Caterham with 220 BHP weighing 500 kgs. That s for the time I want to shake some cobwebs. Also my everyday car is a 189 bhp Lotus Elise. The TC is for driving sedately along country roads.[u][/u][u][/u]

[u][/u][u][/u]

[u][/u][u][/u]

[b][i]Norman Verona[/i][/b][u][/u][u][/u]

11 Cherry Close, Royston, South Yorkshire S71 4LZ[u][/u][u][/u]

Phone: 0044 (0)1226 728811[u][/u][u][/u]

Mob: 0044 (0)741 9905 741[u][/u][u][/u]

[b][i]Web: www.frenchblat.com[/i][/b][u][/u][u][/u]

[u][/u][u][/u]

[b]From:[/b] mg-tabc@yahoogroups.com [mg-tabc@yahoogroups.com] [b]On Behalf Of [/b]David James dr.david.james@gmail.com [mg-tabc] [b]Sent:[/b] 18 February 2018 10:10 [b]To:[/b] mg-tabc@yahoogroups.com [b]Subject:[/b] [mg-tabc] Re: Tappet clearnace on TC (1949)[u][/u][u][/u]

[u][/u][u][/u]

[u][/u][u][/u]

I had noticed play in the distributor shaft of my 1948 TC, along with quite a lot of oil in the distributor top, and thought this might be the cause of the noisy engine. So I replaced the bushes in the distributor body. This cured the oil problem, but not the clatter. So I used the method given on the MGCC Y-Type Register web site to determine that the camshaft was still of the type that required a 19thou tappet clearance. On the basis that there are indents on the rockers that my feeler gauge would not detect, I set the clearance to 17thou. It is still noisy, but I am reluctant to reduce the clearance further. David (TC4985)[u][/u][u][/u][u][/u][u][/u]

[eworpe]

Hi Clive, Woe be it for me to be critical but aren't you also making a bit of an assumption :=)) Eric. ________________________________________ From: CLIVE SHERRIFF csherriff99@gmail.com NEVER, but NEVER make assumptions.

[Benny Grumer]

Norman

I set the gap without a filler gauge. The threat on the adjusting screw is 1 mm so half a turn gives .019"….

I turn the screw in to the point there is zero gap an than half a turn out and I am done.

Regards

Benny

__________ Information from ESET NOD32 Antivirus, version of detection engine 16941 (20180221) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com

[John Kallend]

I have an AEG122 in TC0845. Tappets set at 0.019. Never had a problem in 40+ years. Car is noisy anyway. _____________________________John KallendProfessor EmeritusDepartment of Mechanical, Materials and Aerospace EngineeringDepartment of PhysicsIIT, Chicago

On Wed, Feb 21, 2018 at 9:36 AM, Benny Grumer jaguarb@inter.net.il [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote: [u][/u] Norman[u][/u][u][/u]

I set the gap without a filler gauge. The threat on the adjusting screw is 1 mm so half a turn gives .019" .[u][/u][u][/u]

I turn the screw in to the point there is zero gap an than half a turn out and I am done.[u][/u][u][/u]

Regards[u][/u][u][/u]

Benny[u][/u][u][/u]

__________ Information from ESET NOD32 Antivirus, version of detection engine 16941 (20180221) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com