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Strange problem mg midget 1500

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Mavrick Avatar
Mavrick Jan Jacobs
Brugge, West vlaanderen, Belgium   BEL
By the way my spark plugs look like the foto attached, one is wet the other black dry.

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2CFE6AD7-1D91-45D6-BB21-1C25D1FC61CE.jpeg    8 KB
2CFE6AD7-1D91-45D6-BB21-1C25D1FC61CE.jpeg

Sarge101st Avatar
Sarge101st Silver Member Brian S
Carlisle, PA, USA   USA
1977 Triumph Spitfire 1500 "Biggles"
1979 MG Midget 1500 "Grrr"
1980 MG MGB "Piddles"
Really a stab in the dark, but a compression test might be warranted at this point.

My mind is wandering off to head things now, gasket, stuck valve, something of that ilk.

Again, a wild guess from afar, but that plug looks awfully oil-covered to me...



Edited 1 time(s). Last edit at 2018-05-16 05:49 PM by Sarge101st.

CountBasey Avatar
CountBasey Thomas Basey
Brunswick, OH, USA   USA
1976 MG Midget 1500 "Opus"
Jan,

Yes, I have the same exact year and the exact same carb and intake setup - if you still want pics I can do that, but as the prior post said I think we’re beyond the carb...

Oil on that plug is bad news. Either a stuck valve, or oil is getting past the valve seal from the top and leaking into the cylinder. The other possibility is a bad piston ring and the oil is coming up from the crankcase. Neither is good news, but both are fixable (but not by me - I’d be calling folks in my MG club for help myself).

Unfortunately it’s beyond my skill set (by myself). Sure sounds like you need to pull the head and take a look.

Best of luck.



Thomas (Count) Basey
Member of Emerald Necklace MG Register - www.mgcleveland.com
________________________________________________________

“With each replacement of parts, my British car slowly becomes Chinese.”

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Mavrick Avatar
Mavrick Jan Jacobs
Brugge, West vlaanderen, Belgium   BEL
Thomas,

This afternoon I pulled the spark plugs out, and check the rockers if they are 0,25mm. Today I will do a compression test to see if there is a problem if not and I hope not then this part will be eliminated.i think the black spark plugs are like that because I am trying and trying to start without choke and with choke and I am flooding the engine with gasoline.
So I will keep you posted
Did you get rid of the emission control stuff that was on the car originally. If yes what did you plug?

Greets
Jan

CountBasey Avatar
CountBasey Thomas Basey
Brunswick, OH, USA   USA
1976 MG Midget 1500 "Opus"
In reply to # 3737656 by Mavrick Thomas,

This afternoon I pulled the spark plugs out, and check the rockers if they are 0,25mm. Today I will do a compression test to see if there is a problem if not and I hope not then this part will be eliminated.i think the black spark plugs are like that because I am trying and trying to start without choke and with choke and I am flooding the engine with gasoline.
So I will keep you posted
Did you get rid of the emission control stuff that was on the car originally. If yes what did you plug?

Greets
Jan

Jan,

I would think if if were just flooding it would be all the plugs, not just one or two that were coated. But here’s hoping you are right.

My car is pretty much stock for 1976. All the emissions stuff is still there (air pump and rail, EGR valve, etc.). There is one line missing to the charcoal canister, but I know where it should go. Once you do your compression test,let me know if you want to see anything from mine.



Thomas (Count) Basey
Member of Emerald Necklace MG Register - www.mgcleveland.com
________________________________________________________

“With each replacement of parts, my British car slowly becomes Chinese.”

Mavrick Avatar
Mavrick Jan Jacobs
Brugge, West vlaanderen, Belgium   BEL
Thomas,

Did the compression test all 4 cylinders 165 psi so all super oke.

Greets

Jan

Sarge101st Avatar
Sarge101st Silver Member Brian S
Carlisle, PA, USA   USA
1977 Triumph Spitfire 1500 "Biggles"
1979 MG Midget 1500 "Grrr"
1980 MG MGB "Piddles"
If we're now satisfied on the downstream side, lets go back upstream to why one plug is soaked and it runs uneven.

1) The plug is not burning its mixture in its cylinder, so that one either intermittently firing or not at all. That would be anything from the cap, loose or broken HT lead, or a bad plug. I know they are new but every now and then a bad something slips past. Electrically check them, pretending they are old.

2) A grossly open intake manifold leg (gasket or crack) will exhibit uneven burn.

Again, guesses from afar.

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CountBasey Avatar
CountBasey Thomas Basey
Brunswick, OH, USA   USA
1976 MG Midget 1500 "Opus"
I’m with Sarge101 on this one. Was only one plug oily (wet)? I would clean the plugs up, and switch the cylinders they were originally in. If the same plug fouls again, then could be a bad plug. If the same cylinder fouls another plug - then maybe a bad wire or something in that chamber (although you said compression was good).

After my car was started and ran today, I very reluctantly disconnected the plug wire from cylinder #2 (couldn’t easily get to #1 behind the alternator) and started it back up for only a few seconds. It sounded remarkably like your video although I didn’t try to rev it up, I just shut it back down quicky (curiosity to see what a missfire would run like). Sure sounds like you are running on three cylinders instead of four.



Thomas (Count) Basey
Member of Emerald Necklace MG Register - www.mgcleveland.com
________________________________________________________

“With each replacement of parts, my British car slowly becomes Chinese.”

Mavrick Avatar
Mavrick Jan Jacobs
Brugge, West vlaanderen, Belgium   BEL
Oke yesterday, I changed the ignition coil started up and everything went well, after some fine tuning, I dead now I will let the engine cool down and try to start again. That done after 3 hours I tried to start same problem as ever. I got the spark plugs out to check again and they where all 4 super good. So there has to be something with my stromberg.

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Attachments:
434A37DC-1FC2-433F-B995-D1A3F531248D.jpeg    27 KB
434A37DC-1FC2-433F-B995-D1A3F531248D.jpeg

CountBasey Avatar
CountBasey Thomas Basey
Brunswick, OH, USA   USA
1976 MG Midget 1500 "Opus"
Sorry if I took you in the wrong direction. After pulling the one spark plug cable on mine I would have bet you were running on three cylinders.

Torn or damaged diaphragm under the dashpot? I still say there is a strange sucking sound when you rev the engine (unless thats just how that air cleaner sounds when drawing in air).



Thomas (Count) Basey
Member of Emerald Necklace MG Register - www.mgcleveland.com
________________________________________________________

“With each replacement of parts, my British car slowly becomes Chinese.”

Mavrick Avatar
Mavrick Jan Jacobs
Brugge, West vlaanderen, Belgium   BEL
Hi, the diaphragm is new and oke, but you are correct the sucking for air is strange, it’s like she gets to much are than gasoline, so I will look in to that.

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