- Thread starter Nomad
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colnerov
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As regards the oil to use, back in the day one of the motoring magazines did a comparison of oils in three different engines, the results were interesting and surprising. One thing was that one of them gave the best results with no oil, so it depends on the individual engine. Also as said by @mr haynes try and see if you can get an HIF6 or HIF44 they are more leak free and stay in tune longer. You should hear @harveyp6 on the subject. 
It doesn't matter, someone will know better!!What the hell does HE know?
If the engine speeds up when you use the piston lifting pin, the mixture is too rich. If it slows down, it is too weak. When the mixture is correct, lifting the piston should cause the engine speed to temporarily slightly increase, then return to normal.
8ob
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Summary: SU carbs are super simple but unreliable and often wrong when they left the production line"
SU carbs have been on a lot of cars I have owned over the years, I have never had an issue with any of them
Not sure whether the 1800 marina had a carb heat shield as standard, might be worth fitting one while you are tinkering.
Bob
The increased ethanol content of modern fuels has killed many many otherwise good bits of kit that had the earlier rubber / neoprene parts . My 23 yr old chainsaw being a prime example :- rubber on the carb needle valve tip , priming bulb , fuel lift tube and return pipes all disintegrated . In the carb I noticed a very fine sediment not sure if that was partly caused by ethanol or not .
Smallfry
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SU carbs are great. Better than anything else for a road car that uses the full engine rev range.
Only problems I ever remember having was throttle spindle wear, and the float valve leaking ....... usually because fuel pressure too high from an uprated pump.
Heavy handedness or stupidity could kink or break the fuel transfer tube.
Some had a poppet valve in the butterfly disc. This need soldering up or replacing with a plain type.
HIF series carbs are better, but I would stick with what you have, provided there is not too much slop in the throttle spindle. ISTR that they do oversize spindles though.
Only problems I ever remember having was throttle spindle wear, and the float valve leaking ....... usually because fuel pressure too high from an uprated pump.
Heavy handedness or stupidity could kink or break the fuel transfer tube.
Some had a poppet valve in the butterfly disc. This need soldering up or replacing with a plain type.
HIF series carbs are better, but I would stick with what you have, provided there is not too much slop in the throttle spindle. ISTR that they do oversize spindles though.
Olderisbetter
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Look at A.C.Dodd on YouTube he is a wealth of knowledge
Nomad
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The guide is helpful with clear instructions - ideal for somebody like me with no experience of these carbs
Many Thanks !
Nomad
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Simple is exactly what I need - the guide is ideal with simple info in layman's terms.
Many thanks
james butler
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not just that but actually attacks metals too over time
Beware: Ethanol Fuel Damaging Carburetors
I recently had a learning curve working with ethanol fuel that went bad. Today's blog post is to bring attention for those that are not aware of how corrosive ethanol fuel really is. Inside the post I will cover why ethanol fuel is corrosive and how to beat it before it strikes. Read the full...
www.classicbritishspares.com
Melvyn Best
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Drinking petrol? I would start at the basics, check compressions, valve clearances (too tight will cause high fuel consumption/running problems, ) points settings/dwell angle , ignition timing , mechanical and vacuum advance , plugs , air filter , induction air leaks etc before attempting to adjust the carb. A cheap vacuum gauge is a very underrated tuning toolThe car made a 159 mile trip yesterday so the rebuilt carb works.
It’s drinking petrol and runs “ok” with rare burst of performance so something still needs work but it’s progress
james butler
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start with simple things
i found the choke cam that drops the level of the brass needle seat sometimes got stuck down causing horrific fuel consumption
i found the choke cam that drops the level of the brass needle seat sometimes got stuck down causing horrific fuel consumption
james butler
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also meant to say i fixed it with a blob of grease on the cams 
just double check that when you turn the choke off it really is off
just double check that when you turn the choke off it really is off
