E21 316 bogging down on full throttle

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Dalton2085
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E21 316 bogging down on full throttle

Post by Dalton2085 »

Hi Guys

My e21 316 has been dry stored for the last 12 years. It has had a new battery, plugs, leads, distruibutor cap and arm, new air and fuel filter.

It ideals (a bit high), when i apply the throttle it is fine at half revs but when i open the throttle fully it bogs down and dies unless i close the throttle. If I slowly open the throttle in small increments it does run at full throttle.

It seems like a fuel issue although any thoughts are really welcomed.

Thanks guys


E21noob
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Re: E21 316 bogging down on full throttle

Post by E21noob »

I'm not an expert but this sounds like a carburettor issue.

I assume yours has a Solex 32/32 DIDTA - these are know to cause problems.

Send it off for å refurb, replace it, or consider a weber upgrade.

Plenty of threads on carbs if you look around.
Dalton2085
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Re: E21 316 bogging down on full throttle

Post by Dalton2085 »

Thanks for this info. Will look into it.
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Jeroen
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Re: E21 316 bogging down on full throttle

Post by Jeroen »

Where's Peter our carb expert when you need him? :wink:
Regards/groeten, Jeroen
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e21_lyf
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Re: E21 316 bogging down on full throttle

Post by e21_lyf »

Did you manage to sort this issue out? I'm saying a carb clean and shot of fuel additive :logospin
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E21-driver
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Re: E21 316 bogging down on full throttle

Post by E21-driver »

Hi,

this might be an issue with the acceleration pump diaphragm. Or enrichment valve diaphragm. You can check it easily. If you have the stock Solex DIDTA, then you can open the top triangle cover and the lateral square cover, where the diaphragms are located. If they are too hard or worn out, the carb needs an overhaul and a service kit. Be careful, there are springs unter the covers. If you loose them, then the game is over.
Before starting with this, check the carb foot and cover for leaks with brake cleaner, while the car is idling. Check also the vacuum advance line for leaks.
M.
1982 315 reseda
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Peter V.
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Re: E21 316 bogging down on full throttle

Post by Peter V. »

E21-driver wrote:Hi,

this might be an issue with the acceleration pump diaphragm. Or enrichment valve diaphragm. You can check it easily. If you have the stock Solex DIDTA, then you can open the top triangle cover and the lateral square cover, where the diaphragms are located. If they are too hard or worn out, the carb needs an overhaul and a service kit. Be careful, there are springs unter the covers. If you loose them, then the game is over.
Before starting with this, check the carb foot and cover for leaks with brake cleaner, while the car is idling. Check also the vacuum advance line for leaks.
M.
Those are indeed the basics first.

An item that appears also at the DIDTA is airleakage at the axle of the throtlevalves. During idle spray some brakecleaner near the bushes and listen if the RPM's change.
If all items like above does not give you any respons then please respond again.
Gr Peter V.

.Some say he eats nuts and bolts for breakfast, all we know is he is called the carburetorman.

BMW E21, 1981 320/6 Ascot Grau.
BMW E85, 2004 Z4 2.5i Sterling Grau.
BMW F25, 2014 X3 xDrive 2.8i Space Grau.
Dalton2085
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Re: E21 316 bogging down on full throttle

Post by Dalton2085 »

Peter V. wrote:
E21-driver wrote:Hi,

this might be an issue with the acceleration pump diaphragm. Or enrichment valve diaphragm. You can check it easily. If you have the stock Solex DIDTA, then you can open the top triangle cover and the lateral square cover, where the diaphragms are located. If they are too hard or worn out, the carb needs an overhaul and a service kit. Be careful, there are springs unter the covers. If you loose them, then the game is over.
Before starting with this, check the carb foot and cover for leaks with brake cleaner, while the car is idling. Check also the vacuum advance line for leaks.
M.
Those are indeed the basics first.

An item that appears also at the DIDTA is airleakage at the axle of the throtlevalves. During idle spray some brakecleaner near the bushes and listen if the RPM's change.
If all items like above does not give you any respons then please respond again.
Thanks for this info gents. I have just got back from holiday and I'm going to start investigating this week. Will keep the thread updated.
Dalton2085
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Re: E21 316 bogging down on full throttle

Post by Dalton2085 »

Hi guys

I have recorded a vid so hopefully someone might reconise the issue.

Thanks

https://youtu.be/kEhgTetdCFg
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