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I thought this was odd.

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Nunyas

Nunyas

Yoda
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So, there I was, replaced the speedo cable on my B, that works most excellent again. While I was at it, I replaced the courtesy lamp on the center console; the amount of light that thing emits is nearly obscene now. I installed a radio blanking plate, the quality of which I was impressed with. For the price I paid, I was half expecting it to be made of plastic, but this thing was an all metal 3-piece deal. The MG badge was chrome plated metal, the black backing plate was black painted metal, the chrome trim ring that goes around all of that was metal, and the fasteners that hold it all together is metal as well. but then, i digress...

Anywho, the odd thing is, when I finished all that, I decided to look into an 'odd' miss that I've been experiencing lately. I started with the iggy. Pulled the lead from the coil found the coil side to be lookin' nice, but the dizzy cap side needed a little love. So, love it received. Then I started pulling the leads to the plugs, all of which appeared to be in good nick. Finally, I started pulling the plugs, 1, 2, and 4 looked good, and light'ish tan color to them. But #3, that one had an obvious "i'm too lean" white'ish color to it. This strikes me as odd, because the plumbing for the gulp valve puts the air in-let closer to 1 & 2. In the past, 1 & 2 have always had a slightly more lean appearance to them. This weekend however, #3 appeared to be much leaner than the rest of the cylinders.

What do you guys think about that? I'm currently considering getting new plugs, leads, and dizzy cap; the ones on the car are about due for replacement. You guys have any thoughts or ideas as to why cylinder #3 would have an much leaner look to the plug than the rest of them? Blockage in the intake path maybe?
 
I know #3 burns a bit hotter than the rest due to some casting consessions, but not to a point of being -that- different... have you means to do a compression test? A dry one then "wet". Or a leak-down test. That would actually give a bit more insight. Not too likely the intake runner would be restricted, IMO.
 
oh, it was very different, the plug looked like it was dusted white when compared to the rest of the plugs.

hmmmm... sounds like an excuse to go buy more tools... how much are compression gauges running these days?
 
Not that expensive. Check NAPA first, so you get a tool not a toy, IYSWIM.

There could also be some coolant sneaking in there... any trace of exhaust "white-white" smoke on startup?
 
negative on the smoke... but I did notice a faint coolant smell the other day while driving. It didn't smell like burning coolant; it smelled more of coolant dripping out of the over flow. I figured it to be one of the other cars around me at the time, because the smell came at a stop light and went away after traffic started moving again.

Haven't checked the valve lash yet either, but thanks for reminding me. I need to check that too as it's about time for it.

keep'em coming, the more stuff I can look at this weekend the happier I'll be.
 
BTW: were the plug gaps all the same? They tend to widen a bit as time goes on.
 
You know you could always have a bad plug, I know not likely but.............
 
gaps were the same. Currently have Bosche Platinums in there, but considering changing them out for NGKs, because I believe that's what a lot of people on here seem to recommend for our B-series lumps.

The tiny electrodes on those Platinums has recently become a source for me to question their actual ability to deliver a nice big spark... not only that but they seem to be more difficult to clean up than regular plugs thanks to the way they cover it in ceramic all the way to the tip.
 
Swap plugs around and see if prob follows the plug?????
 
hmmmm... now there's an idea ...
 
And that is what I ment by is the plug ok.
 
Yep Jack. That'd tell something, true.

Just swappin' for NGK's or Champions would be better. For whatever reason, our B fouls Bosch Plats in no time but runs FINE with Champion RN9-Y's... the Alfa is just the reverse. Bit different heat range for each car but the outcome is the same. Go figger.
 
Nunyas, The smaller the tip the more concentrated is the energy. Also sounds like you have a fairly cool plug installed.---Fwiw---Keoke
 
Keoke... you got a reference chart handy? Can't recall if the B calls for Bosch WR7DP or WR9DP's. Champ's are RN9Y's.
 
No Doc I do not have a chart handy. However, I run the WR7DP plugs in the Big Healey with great success. Short drives or long hi speed touring they work a treat.---

Keoke /ubbthreads/images/graemlins/savewave.gif--Hey Doc I found the Bosch catalog; It lists the WR7DP Platinum or the W7DC Super plug for the MG 1962-to-1980 Cars. Looking back a bit I can remember the Volvo B18/20 Four bangers preferred the Super plugs?---Keoke
 
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