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Cars for sale / 1971 MGB
« Last post by amgba on February 20, 2020, 01:04:49 PM »
1971 MGB. Complete mechanical restoration of very solid Texas car. Built for optimal performance & reliability. Performance engine rebuild w/1 ¾" carbs. Stainless steel headers, exhaust. Suspension rebuilt, lowered 1" with stiffer springs, nylon bushings, camber adjusting A-Arms. New leather interior, weather gear, brakes, many electrical components. Lots of spares. $16,500. Have receipts for $24K. (910) 687-0211, .
Suspension Related Items / Re: Brake Fluid
« Last post by JohnTwist on February 14, 2020, 03:20:17 PM »
hose warnings about brake fluid were valid before about 1970.  My suggestion is to use DOT 4.  DOT 3 is OK, too, but DOT 4 removes paint a little slower.  Hope this helps.
John H. Twist
Suspension Related Items / Brake Fluid
« Last post by march2020 on February 14, 2020, 03:08:30 PM »
I purchased a NOS factory master cylinder for the '77-'80 MGB, made by Girling or Lucas i can't remember. It's not an aftermarket one. It is a new one the factory would have used back in the day.  It's also not recently made.I would guess it was made in the late 70's.  I bought it because I want original quality.  The question for you is which brake fluid should I use?   
I ask because I read of 'natural rubber' in older systems or even SBR type rubber from the 70's being not compatible with borate esters in DOT4.  I don't want to ruin a nice NOS master cylinder.  What do you think? 
Rick Lazio
Engine Related Items / Re: SU Linkage Parts
« Last post by JohnTwist on February 14, 2020, 03:21:29 PM »
That body shell is looking VERY nice!

The only two people in the USA that come to mind are:

Joe Curto who is the SU king in the country: and

Paul Dierschow of Sportscar Craftsmen in Denver, Colorado:  CPaul has SO MANY used parts.

Maybe one of these guys has a clue or can point you to someone who can assist.
John H. Twist

Engine Related Items / SU Linkage Parts
« Last post by march2020 on February 14, 2020, 03:13:48 PM »
I am doing a bare metal up restoration of a 1980 MGB Roadster, converting it to chrome and installing an SD1 3500 V8, five speed box and a V8 back axle.  I have a modified SD1 plenum and a matching fabricated inlet adaptor to mount the two SD1 HIF6 carbs, See the photos.

What I am missing at this time is the original factory V8 linkages between the carburetors as these are no longer available.  I see on eBay some linkage bits which I may be able to adapt to suit the twin HIF6 set-up.

Do you know of any source in the USA of SU linkage pieces which I could buy to recreate the original factory V8 set up on the MGB GT V8 with the cast aluminium adaptor, part BHH988?
Jim Barin
Engine Related Items / Re: Engine Identification
« Last post by JohnTwist on February 14, 2020, 03:23:57 PM »
Here are some photos that have information about engine identification.  Here is a bit more:

The three main MG engines have a tach drive at the rear of the camshaft.

The 18GB engine is set for a dynamo, the newer engines also have a set of vertical 5/16-24 threads to accept the rear mount of an alternator. 

The 18V engines use a very different front engine bearing plate and a single row chain and sprockets for the cam.

The 1968/69 rear engine plate has a hole about the size of a silver dollar on the LH bottom.

Hope this little bit helps.
John Twist


Engine Related Items / Engine Identification
« Last post by march2020 on February 14, 2020, 03:14:31 PM »
I bought a 1963 MGB completely dissembled back in June. The previous owner had the motor rebuilt and indicated it was a 5 main engine. I have not pulled the pan to verify. My challenge is determining if it is an 18 GB or 18 GD because there is no engine ID tag. Can you provide some help?

Tom Bishop
Westerville, Ohio
Engine Related Items / Re: Breather Tube to Aluminum Valve Cover
« Last post by JohnTwist on February 14, 2020, 03:28:24 PM »
A;   Drill a pilot hole then follow with a ¼” NPT tap into the valve cover exiting the right rear of the valve cover pointed towards the windscreen washer container.  Use a ¼” pipe nipple (grind off the excess that protrudes into the interior of the engine so there is no chance of fouling the valve springs).  The ¼” inside diameter is much too large for proper ventilation. 

It must be reduced to 5/64”.  I found it easiest to use my torch and solder several washers of descending size on the end of the pipe nipple, ending up soldering the pipe shut.  Then drill that 5/64” hole through the solder in the middle of the smallest washer

Use a ¼” pipe nipple, it needs not be barbed – it’s a 95¢ hardware store item.  That’s ¼” inside and ½” outside.  It’s a taper fit into the valve cover so it’s tightened VERY snugly.  But, again, grind off the excess that protrudes into the inside of the VC so it has NO chance of fouling the rocker assembly.

Hope this helps.
John Twist
Engine Related Items / Breather Tube to Aluminum Valve Cover
« Last post by march2020 on February 14, 2020, 03:15:41 PM »
I need help regarding adding a breather tube to an aluminum valve cover. The hose connected to it will come from the charcoal canister.

David Braun
Engine Related Items / Re: Engine Compression
« Last post by JohnTwist on February 14, 2020, 03:29:55 PM »
A:   Back up a couple of steps.  When an engine comes to rest, two valves remain open.  If the engine sits for a period of time –months / years – then those two valves develop some rust on their faces and cannot perfectly seal.  So, before I determine compression, I run the engine for ten minutes and then check the compression.  If something’s amiss – a variation of more than 10% cylinder to cylinder, then I adjust the valves (0.015” in your case), and check the compression yet again. 

If the compression is extremely low in one cylinder, the problem could be the valves, the piston/rings, or the head gasket.  In ALL these cases the head needs to be removed to fix the problem – so I never squander time trying to figure it out from above.  Once the head’s off the problem is usually easily seen.

Support the head upside down on the bench and fill each of the combustion chambers with fluid.  Gasoline is handy but dangerous.  Fuel oil / mineral spirits are effective.  If one of the valves is leaking, you’ll see the fluid drip out of an inlet or (more likely) an exhaust port.

Position the pistons at the same height.  Pour that same fluid into the cylinders – say one inch above the surface of the piston.  Over the next fifteen minutes look at the fluid height in each cylinder.  If the rings are faulty in a cylinder (or worse) the fluid will escape down the sides of the piston and into the sump more quickly than the others.

Cylinder compression – the raw number – is a function of the valve lash, the integrity of the valves/rings/gasket, the heat of the engine, and the speed it’s spinning over.  I’ve never noticed a difference in compression by the position of the throttle.  The important thing is that they’re within 10%.  Of course, a true figure of less than 90 psi indicates something amiss (list above) or cam timing.

There are cylinder heads available on eBay and at swap meets.  For example, the Chicago Area swap meet every late winter, early spring always has cylinder heads there.

Hope some of this helps!
John Twist
Safety Fast!
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