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From: G & J Swann-Pric [mailto: swann-price@... ] Sent: Wednesday, April 21, 2004 1:20 PM To: midgetsprite@yahoogroups.com Subject: RE: [midgetsprite] Re: Heater valve A common mod is to replace the locally operated valve (ie one with the hand wheel attached on top) with a remotely operated one which are much more commonly available. The advantage of this is that you can then buy a control cable (either a heater control from say an early mini or a choke control for a Spridget - I've used a rotary control from a B in my car) mount it in a suitable... MORE
Ben, ive got one of these on my 1500, it does make a difference. However, the precision (or lack thereof) in its manufafcture made it very very diffcult to fit (lots of heating and bending to get pipes that should mate up properly to do just that). However, this has obviousley come off a car so it might be ok. The standard peco back box for this system is very loud. I don't have a problem with it but some passengers do! You;ll need richer needles once youve put this on btw. If your cars lowered, then like me... MORE
G'day Martyn "Stumbling" on initial acceleration is also a syptom of running lean as you crack open the throttle. Once you get to cruising, the combination of damper springs, metering needes and adjustment might give you the right mixture, but the carby piston could be lifting too quickly as you try to accelerate. Try dumping the oil in the dashpots and putting in 20W50 engine oil. avagoodday Colin "Colin@SpriteParts" 31444... MORE
Well after posting the message I cooled off and went back out and looked things over. I know that if the pistons open too quickly the engine will get a lot of fuel and not that much air. So I fiddle with the mixture nut and watched the piston when the throttle was opened. The pistons rose but the headers started to glow red! Argghh, I thought I'd timed the cam in better than that. Has anyone had a vernier cam gear slip on them? I don't remember a torque value on the securing screws, it's the Kent gear.... MORE
mmm, not that I know of (the previous owner did the original conversion and I replaced the weber with a new one). Sounds like that could produce those symptoms. Where does one get one of these? I assumer they are just fitted between the pump and the carb. Thanks, Alan. "Alan Hearnshaw" 31427... MORE
Martyn... Firstly, check the oil level in the carbs and further, is it "thin" 10 wt or the thicker 20 wt. stuff? Secondly, when it "stumbles" off-idle upon initial acceleration...is there smoke of any sort out the exhaust before it finally "catches" and "go's"? Thirdly...check the timing. For a "stumble" upon initial acceleration is not an unknown symptom of too much initial ignition advance. Cap'n. Bob '60 :{) PilotRob@... 31417... MORE
Alan Hershaw....float level Bet you hit the nail on the head Alan, considering color of spark plugs under normal driving conditions. Too much fuel pressure can also be the gremlin. Webers (for the road) prefer about 1.5psi, but no more than 2.5psi even for highly tuned units. You MAY need a fuel pressure regulator? Cap'n. Bob '60 :{) PilotRob@... 31413... MORE
I have a '76 midget with the weber conversion (New carb). Car runs fine under normal use (35,000 miles), but sometimes when idling at lights, the engine will "choke up", and start to falter. Revving the engine will clear it (accompanied by black smoke until cleared). This also can happen doing short stop-start errands in town. I'll get back to the car and it will require full throttle cranking, will misfire and eventually clear once I've given it some revs (accompanied again by the black smoke). Plugs don't show signs of a rich mixture (healthy tan colour) and I... MORE
My son and I have finally finished the Sprite. Now we're work on some final tuning. The engine is a 1098 with a VP3 cam and 1.5/1 rockers, carbs have the rich needles and stiffer springs at Cap'n Bobs suggestion which I agree with. I can get it to idle at 1000 or so but when pulling away it sputters and stumbles. It will rev freely in neutral. Does anyone have an idea what the problem is? Ignition parts are new. Thanks. Martyn "Martyn Eastwood" 31400... MORE
Thanks for your replies After a bit of fiddling with the colortune the problem is now nearly sorted. The rear carb is running a bit rich, but not so bad as to start tinkering. Its mostly dark blue with a bit of yellow. The front carb was running pretty weak and took about 6 clicks to get it a darker shade of blue and is now about as right as I can make it. I've just taken it for another test run and is a lot better althought the exhaust is beginning to smell like it's running rich again!... MORE
Hi all As discussed in the previous thread my 1500 is totally standard bar the K&N filter, which was fitted and set up by the MGOC on their rolling road. However it has always been a bit hesitant, especially pulling away from cold. I also noticed it yesterday when it was fully warmed up and I was driving along at about 40.Ipressed the pedal down to accelerate and there was a definate hesitation, almost like turbo lag. Naturally I checked under the bonnet to see if some wag had fitted a turbo, but alas not! When I bought the... MORE
James... You may have the airflow balanced but you haven't got the mixture balanced. The twin carb. set-ups are "interdependant". You can actually go full lean on adjusment on one, and very rich on the other and the engine will run on all four cylinders but the plugs will "show"....... exactly as your engine does! Go back to "square one" and use the Colortune (excellent tuning tool) CORRECTLY. Cap'n. Bob '60 :{) PilotRob@... 31378... MORE
Hi Terry So what you are talking about fitting is basically a stage 1 tuning kit. My Mini has a stage 1 kit fitted, but it really hasn't made much difference to the insurance premium. About =A310 more per annum or something silly like that. If you do the conversion make sure that you get the right carb needles as well, otherwise it will run horribly rich. Ideally these things need to be set up on a rolling road.............. There are 2 types of K&N filters for the 1275 cars, either 2 separate pancake filters or the deep combined... MORE
I use the valvemaster with octane booster and it certainly stops it pinking when using cheapest unleaded petrol. Terry "terry.isherwood" 31323... MORE
Rob, Do you know the weight? I recently sent some carbs over to the states. They weighed just under 5Kg and the shipping cost came to 48GBP. Guy "Guy Weller" 31320... MORE
I really have no idea. Just guessing but I wouldn't think it weigh more than the carbs, but that's a LOT for shipping. Robert Houston Texan in New Mexico There is a general place in your brain, I think, reserved for 'melancholy of relationships past.' It grows and prospers as life progresses, forcing you finally, against your better judgment, to listen to country music. - Kary Mullis rbhouston@... 31321... MORE
So in theory 1920's and early 30's cars can run happily on premium unleaded. I'm only interested because my father has a '29 OHC Minor and a '34 Morris 10/4. Perhaps a bit of Castrol R to lubricate the stems? Well it smells nice anyway!!The Minor revs like anything (it has to otherwise you would never get above 20mph!!) whilst the Ten is as lazy as they come. What 750cc have you got?, an Austin 7 or a C-type MG Montlhery Midget....drools!! "James" 31311... MORE
James, A couple of points about the fact that lead was not introduced untl mid-30's (and then ommitted again during the war years. The lead does 2 things; 1. It "lubricates" the valve stems. This only became necessary as finer tollerances were introduced and engines ran at higher revs. Not critical for many of the earlier side-valve engines. 2. It reduces pre-ignition. Again much less of a problem on early low-compression engines. I have run an old 750 side valve engine on a mix of petrol and paraffin (kerosene) It was common practice during war year rationing in the... MORE
Sorry to keep this thread going on and on but an interesting (depending on your point of view!) fact is that lead apparently wasn't used in the 20's and 30's anyway. But somehow I doubt that modern unleaded is the same as the 20's stuff....it must have had some sort of additive. Good point re the Metro/Maestro/Montego 1.3 heads, although I would not recommend robbing one off a Mini *evil glares*!! :) A series engines were leaded until '89, so you will be looking for a G plate onwards. Bear in mind you might need to fight Mini, A35... MORE
I forgot to add in my previous reply that you can still get leaded petrol from a number of Bayford/Thrust locations.... http://www.leadedpetrol.co.uk/index.html David "David Jacobs" 31293... MORE
you're right about the possibilities for confusion creeping in with translation - here in the UK the standard grade of unleaded is called 'Premium' and is 95 RON, the higher grade is usually known as 'Super' and is either 97 or 98 RON. LRP (Lead Replacement Petrol) is about 97 RON but there is no national standard, so it could be anything. Regards David "David Jacobs" 31292... MORE
Alan...I believe you. Exactly what I've heard over the last few years regarding unleaded in "leaded" heads in all the tech articles on this I've read. Cap'n. Bob '60 :{) PilotRob@... 31297... MORE
Hi Ben Converting the head by fitting hardened valve seats is the only proper answer. I take the view that the worst that can happen by using unleaded is a valve buring out, in which case all that needs to be done is to have the hardened seats fitted at that point(and a new valve of course!) The additives are bad news as not only are they expensive but if the car is not used regularly it can form a gunge in the tank and clog up fuel pipes and jets etc. LRP hasn't been available where I live... MORE
"I forgot to add...." Yes...I've heard this or seen it in some of the Sports car mags we get over here from "over there". Will leaded continue to be made available on a limited basis for the "older" cars for a reasonable period of time, David? Cap'n. Bob '60 :{) PilotRob@... 31295... MORE
I perceive, David... So when Mark said he was using regular unleaded, he meant "premium" or 95RON? And when he switiched to Shell Optima, (and his engine "appreciated" the change) would I be correct in assuming this would be "super" (2-3 points higher)? Cap'n. Bob '60 :{) PilotRob@... 31294... MORE
