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This is mostly good news!

Dwell angle and points! You may want to ohm the plugwires, and a compression test is a good idea but I think it's now "Onward to the carb!" Diaphragm check, linkage working properly, etc. Did the Haynes book show up yet? /ubbthreads/images/graemlins/wink.gif
 
Did you resolve all your electrical problems? A good set of wiring diagrams are available at www.advanceautowire.com click on stock schematics. They're better than the Haynes'. Make sure all the electrical connectors are clean and secure. A high resistance connection in the white wire circuit can cause ignition problems.
 
The higher the RPM....The more demand is on the coil.
(But you said it revs fine w/o load)

Also the higher the RPM....The more MECHANICAL advance you need.
(Check to see if the centrifugal advance is working)

Other weird things can happen also, like plug wires, dist cap & low battery voltage.

All can cause high speed break-up.
(Not sure what a bad condenser sounds like but, I have heard some strange Halloween-like things about defective ones) /ubbthreads/images/graemlins/grin.gif

EDIT: Buy NGK plugs & If you have Champions.......
Throw em over the hill. /ubbthreads/images/graemlins/grin.gif
 
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I got the gap on the points right, I got the dwell right, and I set the dynamic timing at 13 degrees btdc. When I went for a drive it seemed like the car was being held back.

[/ QUOTE ]

This timing may still be a bit too retarded. I don't know about this vintage of RB car, but 15 degrees is a good dynamic starting point, and 17 isn't bad - as long as you don't get knock under load. My '73 ran very badly at 12 degrees, and smoothed out really well after I advanced to 17. Among the symptoms were a lot of hesitation as you describe, but I also had noticeable carb backfiring - which it doesn't sound like you've experienced.

I haven't gone past 17 BTDC yet - I have a carb rebuild coming up and don't want to introduce too many changes - but this shows that you can get a lot of improvement from small, incremental changes in these engines.

R.
 
[ QUOTE ]

This timing may still be a bit too retarded.

[/ QUOTE ]
Agreed....
I go w/ 12-15 static or 20 at tickover & 30-35 full in.
(Sounds like a lot but, B series engines like it)
 
Maybe I am not settng it right. When I look at the timing marks with the timing light I consider the one "closest" to the ground or the furthest to the passenger side as 5 degree's and the side closest to the drivers side the 20 degree mark, is that correct or am I crazy? as I run the engine up the mark on the pulley goes counterclockwise looking at it from the front of the car and it goes past the timing indicator.
I did check the carb and the diaphragm looked good but I put the new one in anyway. The float level was way off but I got it right I think. and I mad esure the needle seat was at the correct hieght with the special zenith tool.
If when I reinstalled the little wing on the very bottom of the distributor 180 degrees out could that make a difference? I know my manual says to make sure it goes on the same way it came off because it is offset to one side. I would think if I got it on backwards the distributor would not have gone in.
Give me some more feedback guys, the help is much appreciated.
 
'75 B, 18V engine... If the diz went in to it's seat you did that correctly. The timing marks may be a different story. I don't have a "modern" (18V) set of manuals, but the "early' (18GB) engines have the TDC pointer dead-center bottom of the pulley. Four "teeth" for reference and each "tooth" to the right (engine turns clockwise looking from the front) represents 5 degrees BTDC, with a larger one at 15 degrees. You seem to be off by at least 5 degrees, if the two engines are the same (and I believe they are).

HTH!
 
YES Dave. The TDC "tine" of the set of "teeth" would be consistently the one most to the "left" viewing it from the front of the engine. The rest are in 5 degree increments.
 
So this would be 0 TDC

timingchaincover001.jpg

BTW....This is a 1622 chain cover
 
Yup. According to All That is BMC, that's the only TDC I've ever known. The other two teeth are at 5 degree increments before it.
 
Spanky sounds pretty good to go, so far as wrenching goes... /ubbthreads/images/graemlins/thumbsup.gif

Just wanted to make sure he didn't get his lil' Brit. popper all confused. /ubbthreads/images/graemlins/grin.gif
 
Roger-roger.
 
Wow, that's it, spot on. Good job. Now get those parts blasted and painted while you can get to them.
 
It's kind of hard to see but, the pulley rivets have been /ubbthreads/images/graemlins/hammer.gif

After going through 2 pulleys, I decided to get a billet one.
(One part full-proofed, about a gazillion ta go)

Also.....I brazed a timing mark indicator on the TOP of my other timing chain cover.... /ubbthreads/images/graemlins/yesnod.gif.
 
Good move with the timeing mark.
 
Looking at "whatsthatnoise" picture I don't have a larger tooth like that, all mine are small. I will recheck the timing this weekend and let you know.
 
[ QUOTE ]
After going through 2 pulleys, I decided to get a billet one.
(One part full-proofed, about a gazillion ta go)

[/ QUOTE ]

If there's one thing I learned in the Marines, it was that nothing is "fool proof".

erm...

I take that back, it was that while many things can be child proof, tamper proof, water proof, fool proof, or even "idiot proof" nothing is "Marine proof" /ubbthreads/images/graemlins/nonod.gif
 
[ QUOTE ]
Spanky sounds pretty good to go, so far as wrenching goes... /ubbthreads/images/graemlins/thumbsup.gif



Thanks, I do run a tool repair store so I get to turn wrenchs all day.
 
So this MG project is a "Bussman's Holiday"!!!!

As they say down in Oz: Good-onya, mate!
 
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