# 1977 MGB gas smell, stalling

**URL:** <https://community.cartalk.com/t/1977-mgb-gas-smell-stalling/80196>\
**Category:** Maintenance/Repairs\
**Created:** [July 6, 2013, 6:49pm UTC](https://community.cartalk.com/t/1977-mgb-gas-smell-stalling/80196 "2013-07-06T18:49:53Z")\
**Posts on this page:** 13\
**Page:** 1

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**Author:** ![Sita](https://avatars.discourse-cdn.com/v4/letter/s/439d5e/32.png) [@Sita](https://community.cartalk.com/u/Sita)\
**Post date:** [July 6, 2013, 6:49pm UTC](https://community.cartalk.com/t/1977-mgb-gas-smell-stalling/80196/1 "2013-07-06T18:49:53Z")

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After sitting in the garage all winter, I took my MG out for a spin down the road for about 3 minutes, and it stalled and wouldn’t restart. Guessing it was a weak battery, I towed it back. As I was charging the battery, I smelled a strong gas smell in the oil (on the dipstick). The gas smell wasn’t there when I checked it before. I didn’t complete charging the battery as I’m worried to run it fearing damage. There is also a little antifreeze looking fluid down by the oil filter near the front right of the engine. Any thoughts on how I should proceed?

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**Author:** ![Barkydog](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/barkydog/32/2470_2.png) [@Barkydog](https://community.cartalk.com/u/Barkydog)\
**Post date:** [July 6, 2013, 6:53pm UTC](https://community.cartalk.com/t/1977-mgb-gas-smell-stalling/80196/2 "2013-07-06T18:53:48Z")

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The most likely source of gas in the oil is a bad needle and seat in the carb, or failed or misadjusted float, start there. I do not know the engine well enough to hazard a guess on the antifreeze. Oil change is recommended.

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**Author:** ![texases](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/texases/32/862_2.png) [@texases](https://community.cartalk.com/u/texases)\
**Post date:** [July 6, 2013, 7:06pm UTC](https://community.cartalk.com/t/1977-mgb-gas-smell-stalling/80196/3 "2013-07-06T19:06:56Z")

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How was it running before it stalled? Have you pulled the plugs to see if any look different?

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**Author:** ![Sita](https://avatars.discourse-cdn.com/v4/letter/s/439d5e/32.png) [@Sita](https://community.cartalk.com/u/Sita)\
**Post date:** [July 6, 2013, 7:20pm UTC](https://community.cartalk.com/t/1977-mgb-gas-smell-stalling/80196/4 "2013-07-06T19:20:45Z")

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It was running fine before it stalled, but I knew it was going to as I took my foot off the petal and I could here it punker out. Last summer it would do the same thing occasionally, but only when it was cold.

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**Author:** ![Barkydog](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/barkydog/32/2470_2.png) [@Barkydog](https://community.cartalk.com/u/Barkydog)\
**Post date:** [July 6, 2013, 7:25pm UTC](https://community.cartalk.com/t/1977-mgb-gas-smell-stalling/80196/5 "2013-07-06T19:25:34Z")

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More info, could be a choke problem!

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**Author:** ![shanonia](https://avatars.discourse-cdn.com/v4/letter/s/9de053/32.png) [@shanonia](https://community.cartalk.com/u/shanonia)\
**Post date:** [July 6, 2013, 7:33pm UTC](https://community.cartalk.com/t/1977-mgb-gas-smell-stalling/80196/6 "2013-07-06T19:33:30Z")

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The carb may have an auxillary accelerator pump diaphragm that is cracked. The vacuum hose that goes to the AAP diaphragm housing would then be pulling fuel into the carb, instead of just pulling on the diaphragm. (My 1979 Toyota truck had this system, and presented these symptoms.)

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**Author:** ![ok4450](https://avatars.discourse-cdn.com/v4/letter/o/e9bcb4/32.png) [@ok4450](https://community.cartalk.com/u/ok4450)\
**Post date:** [July 6, 2013, 7:46pm UTC](https://community.cartalk.com/t/1977-mgb-gas-smell-stalling/80196/7 "2013-07-06T19:46:46Z")

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No idea on the coolant leak and would hope it’s nothing more than a loose hose clamp, thermostat housing gasket, etc.

The other problem could be related to the carburetors. They use a Grose-jet instead of a float needle and the Grose-jets can be a problem if the engine is allowed to sit idle for months at a time. Removing and cleaning or replacement would be the only option.

That could have led to the gasoline diluted engine oil. The oil needs to be changed because gasoline diluted engine oil is not a good lubricant and continued use will ruin the engine.

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**Author:** ![Caddyman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/caddyman/32/23_2.png) [@Caddyman](https://community.cartalk.com/u/Caddyman)\
**Post date:** [July 6, 2013, 7:49pm UTC](https://community.cartalk.com/t/1977-mgb-gas-smell-stalling/80196/8 "2013-07-06T19:49:29Z")

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The SU carbs have no accelerator pump…But they do have cork floats…I would remove the air-cleaner assembly so you can see the carbs and float chambers and check for leaks and fuel spillage…

The float chambers may have to be rebuilt using components that are ethanol resistant…

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**Author:** ![Sita](https://avatars.discourse-cdn.com/v4/letter/s/439d5e/32.png) [@Sita](https://community.cartalk.com/u/Sita)\
**Post date:** [July 6, 2013, 7:53pm UTC](https://community.cartalk.com/t/1977-mgb-gas-smell-stalling/80196/9 "2013-07-06T19:53:18Z")

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Thanks I will change the oil, and check gaskets, hoses. It has a single Weber carb now, after replacing the Zenith Stromberg from the past.

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**Author:** ![keith](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/keith/32/5518_2.png) [@keith](https://community.cartalk.com/u/keith)\
**Post date:** [July 6, 2013, 9:44pm UTC](https://community.cartalk.com/t/1977-mgb-gas-smell-stalling/80196/10 "2013-07-06T21:44:18Z")

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You also have a mechanical fuel pump, if the diaphragm leaks, it dumps raw gas into the oil as well as starving the engine for gas. I’d start with checking the fuel pump.

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**Author:** ![missileman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/missileman/32/1366_2.png) [@missileman](https://community.cartalk.com/u/missileman)\
**Post date:** [July 7, 2013, 12:25am UTC](https://community.cartalk.com/t/1977-mgb-gas-smell-stalling/80196/11 "2013-07-07T00:25:33Z")

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+1 for Keith. The fuel pump is often overlooked as a cause for dumping gas in your oil.

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**Author:** ![Barkydog](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/barkydog/32/2470_2.png) [@Barkydog](https://community.cartalk.com/u/Barkydog)\
**Post date:** [July 7, 2013, 12:37am UTC](https://community.cartalk.com/t/1977-mgb-gas-smell-stalling/80196/12 "2013-07-07T00:37:42Z")

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Pray tell how does a broken fuel pump get gas into the engine, as far as I know the pump is inline, electric.

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**Author:** ![missileman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/missileman/32/1366_2.png) [@missileman](https://community.cartalk.com/u/missileman)\
**Post date:** [July 7, 2013, 1:14am UTC](https://community.cartalk.com/t/1977-mgb-gas-smell-stalling/80196/13 "2013-07-07T01:14:39Z")

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@Barkydog…older engines used fuel pumps mounted on the engine and were driven by an offset drive. When the inner rubber seal ruptured…the gas went straight into the crankcase. Electric fuel pumps did not come into widespread use until fuel injection came along. Fuel injection requires a lot more fuel pressure than a carburetor does…50-65psi as opposed to a carb’s 6-7psi.
