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But of course in the UK most of these have different names, and some - like the "sidemarker lamps" don't exist at all! And a "quarter light" as in the original thread topic, is nothing to do with Mr Lucas. The term light refers to a window or pane of glass - as in Elizabethan buildings with "leaded lights", "skylights", "fanlight", "borrowed lights" etc. Remember these are LBCs. Actually, I think everyone should stick with the British naming of parts and drop all references to hoods when you mean bonnets, rotors when you mean discs, fenders when you mean... MORE
midgetSpriter's, I've been trawling the lists for an answer to what seems to be an eternal struggle of getting my Standard Block 1275cc Midget (1970) to run in a reasonable fashion. I've read with interest a number of suggestions and am even more confused as to what the right thing to do in regard to getting this car to run with todays fuels. I've tried the full complement of fuels and am currently running with Premium Unleaded. The engine has been recently rebuilt with the addition of hardened valve seats so I guess I should at least have some... MORE
Brad Fornal was right!!!!! On his advice, I (on the left coast) tuned in "Whose Line Is It?" and Richard Simmons (who is not one of my favorites) to say the least) was funnier than a rubber crutch!!!!!!! I haven't laughed so hard in a long time. Some times I think that they must write and rehearse that show but this one had to be ad-lib. It was side splitting, outrageously funny. I loved the jet ski bit. Thanks for the tip..... I hope someone else saw it. Hee Hee, Bob in San Diego "Robert D. Gardner" 22841... MORE
Don, Have been following your discussion of mystery mods. This may help. It sounds like your 74 has twin carbs. In 75 they went to the single Zenith and the third rubber hose from the canister hooked up to a compression fitting on the back or firewall side of the carb near the bottom. It may be that the emissions equipment was retrofitted. FWIW Rob C 75 Midget robbiesg@... 22781... MORE
"Let sleeping dogs lie" I absolutely agree with you, Don May... why go looking for trouble? Don't fix it if it ain't busted! It would be another matter were there a plan to "convert" the closed loop system. The restrictors on the carb. adjustment nuts are another matter. If a "flat" more "rich" is what is required to eliminate "flat spots" (suspected "lean surge) in cruise, then this one is an easy fix! :) Cap'n. Bob '60 :{) PilotRob@... 22786... MORE
Actually, Bob... Number of carbs notwithstanding, it's probably the same system they used on the single carbed '75, slightly modified for the different engine and/or single carb. set-up and/or closed loop fuel system. However, your input gives us the reason for the compression fitting in the first place...I was not at all sure how it figured into the system, as you may have guessed! And while I do not recall it being a part of the emissions stuff I pulled off my previously owned '74, most likely it was there, in the same place as Don May finds it... MORE
Hi, Don... Well, I have to admit I am doing most of this from memory of what I had on my po'd '74.....this was like 20+ years ago!! Naturally, when I looked at all that stuff cluttering up the engine compartment, I barfed! Then I took it all off, cut the restrictors on the carbs, got a ventilated/ filtered oil filler cap and set up a "ventilated" rather than "evacuated" system. But as Gerard and many others have correctly pointed out, a properly working PCV system is a "good thing" in more than one respect. Yes...the engine breathes in... MORE
Hi Bob, The restrictor inserted in the hose from the oil separator is a modification and not a stock part rather a jerry rig piece of a standard plumbing compression fitting he used to restrict the line, so it was not an official California set up. All I know to do is return it to the direct hose and see how it runs. Although curiosity leads me to wonder why he did it. If I recall correctly in 74 model year the pancake looking PVC valve on top the intake manifold was deleted and the Y connector to the... MORE
Rob, Yes, the 74 still had twin carbs. I did find a diagram that seems to be what yours may be like at: http://www.chicagolandmgclub.com/techtips/553.html Don "Don May" 22783... MORE
Morning Bob, So the collected fumes in the charcoal canister are fed back into the system via the hose to the head cover. It appears there is no collection ports from the fuel bowls on the carburetors. So that would explain their being no hose from them to the canister. That leaves why the PO felt an additional restrictor was necessary, or desirable, in the oil separator to carburetors hose. It was my understanding that as you say "The input fittings within the carbs are in themselves graduated orifices." Think I will take the additional restrictor he inserted out... MORE
Hi, Don May... 1. The missing hose from the carb. to the charcoal cannister MAY be for the fuel bowls with respect to an "anti- runon" valve feature. This is a guess on my part. What this did was create a vacuum at the fuel bowls when oil pressure fell to zero through a solenoid switch when the ignition was switched off. The fuel bowls were vented to the charcoal cannister as part of the closed loop fuel system. The solenoid switch was wired "hot" which is why the PO MAY have disconnected this. 2. The line off your... MORE
Fortunately the carbs I have are older than the car. Emission mods are relatively few and easily dealt with. Thanks for all the info. Rob C 75 Midget robbiesg@... 22774... MORE
I very much doubt if twin HIF 1 carbs were ever fitted to a production car as the philosophy of extra performance using twin carbs had been replaced by using a big single one, by the time HIFs were being used on performance A series engines.This being so, you'd need to find left and right handed individual carbs to make up a set. (was the HIF carb even made in this size?!) You'd do better swapping to twin 1s and modifying the backplate of your filter case to suit, if you're desperate to keep it. David "David Jacobs" 22773... MORE
Agree, but it is a very simple step to replace the "Waxstat" jets with standard jets. Not too expensive either. A worthwhile mod. Guy "Guy Weller" 22771... MORE
SUs are not without their own problems, especially if you get what would have been original fitment on a UK '78 - they have 'waxstat' devices which are supposed to give some temperature compensation to the mixture, by raising or lowering the jets, but they are a pain in the proverbial! David "David Jacobs" 22770... MORE
Once again faced with mystery PO modifications. These have to do with the emission controls. First, particularly on California cars, one must find a proper diagram of the system, something the weak of heart should not attempt from a Haynes Manual. The car in question is a 74 Midget I assume with a stock 1275 First discrepancy . . . The manual, if correct, shows a hose from the valve cover to one of three hose connections on top of the evaporation canister, check . . . that is there. Another hose goes to the gas tank vapor collection... MORE
"Waxstat" devici. I guess they came up with a better way of fuel temperature compensation in the HIF series....like they've got some sort of a fuel temperature sensitive "disc" in there which basically does the same thing? Even so, Vizard states the carb. has a tendency to intially run "lean" when you put your foot in it, after engine compartment temps. have gotten really hot....as in slow travel in heavy traffic, etc. Cap'n. Bob '60 :{) PilotRob@... 22772... MORE
is it possible to replace the hs 1 1/4 twin carb setup directly for hif twin 1 1/4 and get a slight increase in performance? i already have the marque k&n filter and so want to utilize it thanks Rob "R.Eades" 22761... MORE
Hello out there in Midget land, Been following the discussion on Weber carbs and thought I would get advice on a carb switch I am planning. I have a 75 with a stock 78 motor (the original was toast after 7 years of sitting under a tarp) and am thinking of trading the Zenith for the twin SU setup. Seems like a no brainer as it's nearly twice the air flow of the Zenith ace and was standard in the UK for my year. Would appreciate the thoughts and experiences of any Midget listers on this plan. Rob Coxworth... MORE
Rob C. ..... If he double 1.5 SU's were standard for the same engine in European trim, I'd do it and put the Zenith on Ebay in a heartbeat! I think Larry Macy did this with his 1500? Cap'n. Bob '60 :{) PilotRob@... 22757... MORE
"Thanks Bob & Allen for the education" (You owe me big time, Don May!!:):) Assuming it's a stock 1275 you are looking at Don, the correct model of the 45DCOE for the set-up is 45DCOE13. The DCOE is my favorite performance carb. I got mine initially when the shafts of the stock SU's my PO'd '74 started leaking air and needed rebuilding. I figured what the hell and sprung for the 45DCOE tuned for the stock 1275, instead. Glad I did. Worked just fine right out of the box, with the addition of a "deep" K&N filter. Subsequently, the... MORE
Hello Folks I had my Carbs adjusted this past spring on my 1971 MG Midget. At the time they were fine, but now when I start up the car I get a big wiff of gas coming from the tail pipe. I have check all my nuts and bolts and every thing is tight. What is the next step? I have not lost any power and it is running better then it ever has, but the smell is a little to much. Any help would be appreciated Jason 1971 MG Midget 1964 MG Midget "Jason Gross" 22738... MORE
Thanks Bob and Allen for the education. Reason I asked is I am looking for a bugeye and saw one that had a 1275 engine with a Weber on it and did not know the pro an cons of them at all. Don "Don May" 22733... MORE
Don... Dave Vizard's excellent book goes into the "differences" in good detail. Usually, the Weber sidedraught carbs. are utilized along with other performance upgrades such as cam, inlet valve size increase, flowed heads, etc., though they can be used on the stock mechanically sound motor, the benefit in the latter case mostly confined to more "quick response" rather than a true "power" increase due to scads more aiflow available by larger throats. The operative word in the foregoing is "mechanically sound". The engine in question has got to be developing good vacuum for the Weber is a "fixed venturi"... MORE
Ketil.. Fires a couple of times: Does this occur more in wet rather than dry weather? Fr'instance, when was the last time you renewed ignition wires, etc. If it is not humidity related but rather temperature related, then amount of "choke" may require adjustment. Consider: Not continuing to run for the initial start can often be a blessing in disguise with respect to initial oil pressure, whether the filter you are using is equipped with an anti-drainback valve or not. Rate of turnover: There is a certain amount of drag associated with starting with the clutch disengaged in the... MORE
