Oil supply to rocker gear.

[ROSS TAYLOR]

G'day When I took the TC out yesterday I had the misfourtune to find a major oil leak from the tappet cover gasket, I had recently removed the reproduction alloy type cover replacing it with an original "bread tin " unit. My fault of course for not taking the car for a run after fitting it up, But on arriving at my destination ( the annual Classic Motorbike Clubs registration day ) I spoke to one of the smartest mechanics that I have ever met by the name of Dave Morris, Dave is in his 70's and is a wizard on combustion problems, he was amazed at the volume of oil being delivered to the rocker gear ( it was a good leak ) and sugested that a metering pin be fitted to the top banjo connection to reduce the flow to the top end, I know that the clearances in the rocker bushes should meter the oil supply but what is the opinion of the group ? Ross In Tea Gardens

[Paroor]

Dear Ross, The tappet cover gasket may slip away while tightening the cover. This happened to me also. I learned from David Tasa to use some pins to fix the gasket edges in position before tightening the cover. This will to avoid slipping the gasket from position. That means you put the gasket on the cylinder head after applying some sealant on the bottom side. Then put the valve cover on the top. Use some pins to all around the cover to retain the gasket in position with out moving or slipping away. Now tighten the cover. Then remove the pins. The next time you remove the tappet cover the gasket may stay in position sticking to the cylinder and head. Reducing the oil flow to the to top end is another matter. On TC 0448 the oil flow was blocked at bottom hole of the rocker shaft bearer. Some people squeeze the oil pipe to reduce the effective diameter. The will reduce the amount of oil flowing up. I replaced the old oil pipe after rebuilding the engine. Watch the oil gauge for the oil pressure. That is more important for the engine lubrication. It had to spray oil all over the tappet cover while is running. Best regards Madhu -----Urspr ngliche Nachricht----- Von: mg-tabc@yahoogroups.com [mailto:mg-tabc@yahoogroups.com]Im Auftrag von ROSS TAYLOR Gesendet: Montag, 27. Juni 2005 05:54 G'day When I took the TC out yesterday I had the misfourtune to find a major oil leak from the tappet cover gasket, I had recently removed the reproduction alloy type cover replacing it with an original "bread tin " unit. My fault of course for not taking the car for a run after fitting it up, But on arriving at my destination ( the annual Classic Motorbike Clubs registration day ) I spoke to one of the smartest mechanics that I have ever met by the name of Dave Morris, Dave is in his 70's and is a wizard on combustion problems, he was amazed at the volume of oil being delivered to the rocker gear ( it was a good leak ) and sugested that a metering pin be fitted to the top banjo connection to reduce the flow to the top end, I know that the clearances in the rocker bushes should meter the oil supply but what is the opinion of the group ? Ross In Tea Gardens Yahoo! Groups Links

[E.Worpe]

Hi Ross, You're probably correct in stating that the "clearances in the rocker bushes" regulate the oil flow. Some of the oil that leaks past the rocker bushes goes on to lubricate the cam followers and camshaft lobes. Given the high wear rates on these, I would not discourage a good oil flow around them. Might be worth checking your rocker shaft for wear. Regards, Eric. -----Original Message----- I spoke to one of the smartest mechanics that I have ever met by the name of Dave Morris, Dave is in his 70's and is a wizard on combustion problems, he was amazed at the volume of oil being delivered to the rocker gear ( it was a good leak ) and sugested that a metering pin be fitted to the top banjo connection to reduce the flow to the top end, I know that the clearances in the rocker bushes should meter the oil supply but what is the opinion of the group ? Ross In Tea Gardens [Non-text portions of this message have been removed]

[joecurto@aol.com]

Ross on a t type rocker gear with proper fitted bushes and an good shaft the oil flow is minimal, I have seen restrictors in the upper banjo bolt as well as crimped oil feed pipes these are only quick fixes, also with worn rocker gear you get noise and lower oil pressure , The cam and tappets are lubricated by the oil leaving the connecting rods. Joe curto [Non-text portions of this message have been removed]

[John Seim]

The metering pin was used in the P type, and other pre-war engines, with the overhead cam. I suspect part of the reason for the metering pin was to limit the amount of oil supplied to the head valve mechanism. Enough to supply the mechanism, but too much, and the excess would run down the vertical drive to the generator. I have seen various "Band Aid" fixes, to reduce the amount of oil going to the cylinder head, on an XPAG/EG engine. Soldered up, and drilled then a small hole drilled in a banjo bolt for the oil line - block to head. Crimped tube in the feed line, to restrict flow. The rocker shaft wears, as do the bronze bushings in the rocker arms. One of the simpliest ways to increase the oil pressure, and decrease the oil flow to the cylinder head, is to have the rocker arm assembly rebuilt. With everything at the proper clearance, the oil pressure will increase (more flow restriction), and less oil will go to the head, as oil passageway to head is smaller than holes feeding engine main bearings. John Seim Irvine, CA ROSS TAYLOR wrote:

>G'day >When I took the TC out yesterday I had the misfourtune to find a major oil >leak from the tappet cover gasket, I had recently removed the reproduction >alloy type cover replacing it with an original "bread tin " unit. My fault >of course for not taking the car for a run after fitting it up, But on >arriving at my destination ( the annual Classic Motorbike Clubs registration >day ) I spoke to one of the smartest mechanics that I have ever met by the >name of Dave Morris, Dave is in his 70's and is a wizard on combustion >problems, he was amazed at the volume of oil being delivered to the rocker >gear ( it was a good leak ) and sugested that a metering pin be fitted to >the top banjo connection to reduce the flow to the top end, I know that the >clearances in the rocker bushes should meter the oil supply but what is the >opinion of the group ? >Ross >In Tea Gardens > >

[Chip Old]

If I remember correctly, either late in TD production or some time in TF production the bore of the banjo bolt for the oil pipe to the head was reduced to restrict oil flow to the head. If I remember correctly.

On Mon, 27 Jun 2005 08:30 -0700, John Seim wrote: > The metering pin was used in the P type, and other pre-war engines, with > the overhead cam. I suspect part of the reason for the metering pin was > to limit the amount of oil supplied to the head valve mechanism. Enough > to supply the mechanism, but too much, and the excess would run down the > vertical drive to the generator. > I have seen various "Band Aid" fixes, to reduce the amount of oil going > to the cylinder head, on an XPAG/EG engine. Soldered up, and drilled > then a small hole drilled in a banjo bolt for the oil line - block to > head. Crimped tube in the feed line, to restrict flow. The rocker shaft > wears, as do the bronze bushings in the rocker arms. One of the > simpliest ways to increase the oil pressure, and decrease the oil flow > to the cylinder head, is to have the rocker arm assembly rebuilt. With > everything at the proper clearance, the oil pressure will increase (more > flow restriction), and less oil will go to the head, as oil passageway > to head is smaller than holes feeding engine main bearings. > John Seim > Irvine, CA -- Chip Old 1948 M.G. TC TC6710 XPAG7430 NEMGTR #2271 Cub Hill, Maryland fold@bcpl.net

[Peter Roberts]

Try Rocker Arm Specialists in California. Good people. _Peter

----- Original Message ----- From: "John Seim" kingseim@earthlink.net> To: "ROSS TAYLOR" rossmvt@msn.com> Cc: mg-tabc@yahoogroups.com> Sent: Monday, June 27, 2005 11:30 AM Subject: Re: [mg-tabc] Oil supply to rocker gear. > The metering pin was used in the P type, and other pre-war engines, with > the overhead cam. I suspect part of the reason for the metering pin was > to limit the amount of oil supplied to the head valve mechanism. Enough > to supply the mechanism, but too much, and the excess would run down the > vertical drive to the generator. > I have seen various "Band Aid" fixes, to reduce the amount of oil going > to the cylinder head, on an XPAG/EG engine. Soldered up, and drilled > then a small hole drilled in a banjo bolt for the oil line - block to > head. Crimped tube in the feed line, to restrict flow. The rocker shaft > wears, as do the bronze bushings in the rocker arms. One of the > simpliest ways to increase the oil pressure, and decrease the oil flow > to the cylinder head, is to have the rocker arm assembly rebuilt. With > everything at the proper clearance, the oil pressure will increase (more > flow restriction), and less oil will go to the head, as oil passageway > to head is smaller than holes feeding engine main bearings. > John Seim > Irvine, CA > > ROSS TAYLOR wrote: > >>G'day >>When I took the TC out yesterday I had the misfourtune to find a major oil >>leak from the tappet cover gasket, I had recently removed the reproduction >>alloy type cover replacing it with an original "bread tin " unit. My fault >>of course for not taking the car for a run after fitting it up, But on >>arriving at my destination ( the annual Classic Motorbike Clubs >>registration >>day ) I spoke to one of the smartest mechanics that I have ever met by the >>name of Dave Morris, Dave is in his 70's and is a wizard on combustion >>problems, he was amazed at the volume of oil being delivered to the rocker >>gear ( it was a good leak ) and sugested that a metering pin be fitted to >>the top banjo connection to reduce the flow to the top end, I know that >>the >>clearances in the rocker bushes should meter the oil supply but what is >>the >>opinion of the group ? >>Ross >>In Tea Gardens >> >> > > > > > > Yahoo! Groups Links > > > > > > >

[D&J Edgar]

This might be a long shot in the over supply of oil to the rockers but over a year ago Bill Traill wrote the following. Perhaps it is worth a look especially if your oil pressure is on the low side. David Edgar, TC 5108 El Cajon, California ======================= With the engine running, look into the oil filler cap hole. Are the rockers squirting oil like gysers? Recently, I replaced the rocker shaft and bushings. After replacement the oil pressure was 7PSI at idle and 25PSI at 3000 RPM. The new rocker shaft had chamfered holes and the new bushings had large oil holes..the two lined up each cycle on all eight rockers. Oil was squirting over the top of the filler cap opening form #8 rocker at idle. Oil was forced out the cap and ran down the side of the block. I rotated the bushings and drilled new (smaller) holes biased away from the shaft holes. Now there is just a whisper of oil. It drips off the bottom of the rockers, when before it was an 1/8inch stream. OP is now 35PSI at idle and 65PSI 3000RPM. All the old (factory) rocker shafts in my collection have un-chamfered holes. The hole chamfer in the replacement rocker shaft in-effect doubles the hole diameter, so it is more likely to align to the bushing hole. A DPO had placed a .050inch dia. restrictor in the top oil-line head bolt. I removed this long ago. As an experiment, I replaced the restrictor...not much help. I then tried one that was .025inch dia. The oil still shot up .5inch hot from each rocker. OP was improved to 12PSI. Bill Traill Santa Clara, Calif. DCO: TC 5221

[Peter Roberts]

Had my rocker assembly rebuilt last Winter. Gained 10lbs in oil pressure. Getting 50lbs in 95degree heat at full chat. For $110, whatta deal. _Peter

----- Original Message ----- From: joecurto@aol.com> To: rossmvt@msn.com>; mg-tabc@yahoogroups.com> Sent: Monday, June 27, 2005 8:09 AM Subject: Re: [mg-tabc] Oil supply to rocker gear. > Ross on a t type rocker gear with proper fitted bushes and an good shaft > the > oil flow is minimal, I have seen restrictors in the upper banjo bolt as > well > as crimped oil feed pipes these are only quick fixes, also with worn > rocker > gear you get noise and lower oil pressure , The cam and tappets are > lubricated by > the oil leaving the connecting rods. > > Joe curto > > > [Non-text portions of this message have been removed] > > > > > Yahoo! Groups Links > > > > > >