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George... I think you have three problems: 1.The intake manifold mounted PCV system uses the vented/filtered oil filler cap to provide for incoming air. 2. The most effective crankcase scavenging consists of a feed to the PCV valve from below the pistons. 3. The "cover" to the old mechanical fuel pump fitting on the forward left side of the block just above the flange can be used as a "source" for relieving lower crankcase vapor/pressure in place of the old takeoff on the stock timing case cover which no longer exists, in consideration of your new timing cover set-up... MORE
George, Are the rocker shaft and rocker bushings in good condition? If it looses too much oil from the shaft, then it will flood the valve guides and draw oild through to into the ports Guy "Guy Weller" 24292... MORE
Simultaneous smoking exhaust and leaking can be caused by build up of crankcase pressure. The A-series doesn't have a real rear crank seal, and even a slight positive crankcase pressure will cause it to leak, maybe lots. The same for exhaust smoke. With the engine running, remove the oil fill cap and put your hand over the opening to close it off. You should feel a slight vacuum - not a lot, maybe, but enough to feel. Increase engine speed and feel that too. If you feel pressure, even slight, that's a problem. New rings and 200+ psi sounds... MORE
George.... Thought... are you running "vented" or have you got a PCV (valve) system hooked up? Cap'n. Bob '60 :{) PilotRob@... 24302... MORE
My 1400cc engine which sat for a number of years after being built smokes. Between burning and leaking it goes through a quart every 200 miles or so. I've done a hot compression check and get 205, 210,210 and 210. (compression ration is 9.75:1). My thinking is that the problem is in the head, valve stem seals or guides, or with the rocker arm shaft, based on the consistent compression readings. I remember someone saying that even with good compression the problem could be bad oil control rings. Thoughts, comments, suggested diagnostic tests, would be appreciated. Thanks "george07876" 24254... MORE
wow.... 210? seems high for only 9.75:1 regardless.... Did you properly break in the engine before it sat all that time? Rings could simply not be seated yet.... and with that kind of compression, yes the 'blow-by' alone could blow that much oil out very easily. Seriously.... do you have a breather recirculation system? (crank fumes returned to the intake?) If so I'll bet the backs of the intake valves are already a nasty mess of oil sludge. Paul Tegler ptegler@... www.teglerizer.com "ptegler@cablespeed" 24260... MORE
Not familiar with '77 UK cars...maybe they are the same emissions-wise as our US 1500's....not sure. I think there is supposed to be SOME pressure in the tank...shouldn't be enough to get by cap's seal, though. Maybe something as simple as a new gas cap (seal)? But there is a charcoal cannister in there under the bonnet? The fuel tank/sysem vents through this and the engine breathes inbound through this as well? The charcoal cannister also has a vent line which needs to be open... it's pretty small. And the charcoal element needs replacing every once in a while.... MORE
Stewart Well, the spring hanger structures on the Mk1 Sprite are quite different to the spring hanger structures on the 1500. Take it from me, the Sprite Mk1 spring hangers are a lot more complex to repair than the relatively simple 1500 one. And the triangulated structure on the 1500 IS needed, as it's a strengthening area for the rear of the car and as such a very important part the monococque structure. Why don't you buy the excellent restoration book 'Guide to Purchase and DIY Restoration, MG Midget and Austin-Healey Sprite by Lindsay Porter, this book deals with... MORE
My apologies for the terminology gaff. The rotten bits are the inner & outer sills (rocker panels), floor pans, footwell panels, etc. Basically anything behind the wheels has rusted away. The previous owner drove the car year round. Which here in Wisconsin means it was subjected to the brutal winters & corrosive road salt for a third of the year. Thanks for the advice! -Kevin "kari_kevin" 24185... MORE
Kevin First off welcome to Spridget ownership! Unfortunately, you've fallen into the trap many first time buyers of these cars fall into, namely that of purchasing a mechanically sound car that leaves a lot to be desired bodily and structurally. Don't feel bad, many of us have walked this path before you! You have, however, had the sense to limit your investment which is prudent. I'm afraid I am not familiar with the terms 'rocker panels' and 'body tub' or at least I cannot easily translate these terms into actual parts of the car. So until I understand what... MORE
Hello all, Thanks for all the replies on my previous post regarding backfires. Here's my next newbie question: The `77 Midget I picked up a few weeks ago seems sound mechanically. It always starts, runs well, and doesn't leak or burn anything (though I haven't tried taking it through emissions testing yet). I drive it 10 miles to work a few times a week to work the bugs out. The outer body is in fair shape but repairable. The bad news is that the floors & rocker panels (what's left of them) are completely rotten. My question: Is the... MORE
Bob.... I say safety first when it comes to "serious" structure. According to Spridget books I've read, a great deal of structural strength emanates from firewall and is tied into the floors to the rear "bulkhead" which houses the forward rear spring attach points. I could be wrong on this and if I am, I apologize for THIS is the basis of my opinion, which is not very "hands on" learned to the extent of guys like Frank, Chuck, and others far more knowledgeable then I. If the floors and sills were basically sound and mostly there, I might... MORE
First - will someone who has experience resolving off-idle stumble with a Weber DGV on a 1275 please post me off-list. General parameters: 1275, std bore, stock cam, head milled, Crane optical ignition, header. Use an aftermarket electric fuel pump with a pressure regulator set to 3.5 pounds. Engine has never idled this well in the 33 years I've owned it (even as low as 700rpm), idle set at 900rpm, performance above 2000 rpm is excellent. It just stumbles in the 1500 - 1700 rpm range when you hit the gas. Makes double- clutching a bit dicey. Have done... MORE
Hi, Kevin R. ... Suggest you check for a malfunctioning "gulp valve" by substitution and see if this doesn't do the trick? Cap'n. Bob '60 :{) PilotRob@... 24157... MORE
Hello all, new to the list, new to Midgets. Question: I've got a '77 that backfires between shifts under heavy acceleration. I know why; there's excess fuel being dumped into the exhaust between shifts and detonating; I just don't know the cause. The 2 possible causes I've come up with is the air pump is supplying air to the exhaust when it shouldn't (bad valve?) or the non stock exhaust the car has (just 1 tiny Walker muffler) is allowing the fuel laden exhaust to reach air before sufficiently cooled. Which of these are more plausible, or is there... MORE
G'day Brad The valve stem diameters are the same. You can squeeze 1275cc valves into a 1098cc head (12G295) if you want to, but you will need to open the combustion chamber up quite a bit to allow gas flow around the valve, or you are defeating the purpose. Really no great advantage. 1275cc head will fit on 1098cc block, but if you have a high lift cam, and/or 1.5:1 rockers, the exhaust valves will hit the top of the block face. You will need to machine a crescent out of the block, up to .100" deep (I just... MORE
If only so Ed . . . had a truck not tried to back over it or it tried to take a short cut under one during its sordid past. . . It's a bit like a head with a lace collar with slightly crossed bugeyes with bondo covered pineapple cheeks. The tinker has met his match. I'm going to take a long nap. Don "Don May" 24108... MORE
Valve stem diameters are the same for 1098 and 1275 (and 948) engines. So are the rear plate gaskets. If by front gasket, you mean timing chain cover gasket, that's the same too. As to the moving liner, the only way to salvage that block would be to find (or have made) a liner with a sufficiently larger OD than the one in it now. That may not be possible or practicable, so that block may be scrap. I'd rather have a bored block than a sleeved one anyway. "Jeffrey Holmes" 24077... MORE
Cap'n Bob, Appreciate the insight. The last 1275 I drove was a 73 back in 1981. Didn't know jack about such cars so comparison's are impossible. I was planning to lower the rear of the car with a block arrangement that raises the rear axle where it attaches to the spring. Since fitting the new wheels and tires I'm not so sure about this. I had to do some sugery on the rear to eliminate the "tuck-in" flange for clearance. The front wheels were even worse. Had to raise the wheel cutout an inch. Will probably flair them. Do... MORE
Brad... Those sleeves are machined to a press fit, just like press fit piston wrist pins. So I don't think they should be movin' before the pistons do, as in your case, but I'll let Gerard, Frank and the more experienced and "current" engine guys speak for me..they know a lot more about it "hands-on-wise" than I do. The only disadvantage of a "sleeved" block as far as I know is in the area of heat transfer, wherein the sleeved application is at a disadvantage in this respect. The CC blocks are of the stronger variety (as you already... MORE
We put the pan back onto the 1275, but cannot go further until I have the proper gaskets. I will not make them out of silicone!! So, in the interim, we took the 1098 apart. The problem we found, in the removing the frozen pistons, is that there are sleeves on the back two cylinders. One of the sleeves was moving when I was trying to pound the piston out. What holds the sleeve still? I want to build a motor for the Frogeye, to get it on the road, until the 1275 is built. I have two guys... MORE
Capt, I was going to send this directly to you, however, as usual you don't know when to shut your hole (your choice of which hole I'm speaking of). So this is going to the lists you posted on and at least those who haven't already put you on their trash list will see the reply. Cap'n. Bob "Great....Paul goes around breaking the feet of little dumb animals....that's heartwarming news for the soul. Buy a long range squirt gun for crissake!" Paul is trying to be a good guy. As he says, he's got them 'trained' now. I use... MORE
Things at work have finally settled down from the past few months. We have gotten a second weekend off in a row, and I was able to get the mechanic from the truck shop to come over to my house this a.m. at 8:30. Some of you know, the 68 Sprite locked itself into first gear a while ago. It also had the original engine it rolled out of the factory with still in it, all smoking and original. If I am to repair the tranny, I will replace the engine, if only temporarily, to fix the original one.... MORE
Being the owner of a somewhat converted rubber bumper 76 midget,I would like to say that my reasons for the change were simple.# 1 i got a nice car at a great price.#2 After much consideration and head scratching,I decided i could go without any bumpers.Having grown up in the 60S I never got over the hotrod/sportscar thing.Back then a midget/sprite looked pretty tough with no bumpers,A roll bar,wide stripes on bonnet and boot.They even had mag wheels[not minilight style]on some.Any way much as i prefer an older model chrome bumper model this is what i have to work... MORE
Guy Weller writes (in part).."I was trying to resist this as definitely not LCB..." LCB? (Scratching head!) LongCenterBranch?? Purple & Turtle? This is very confusing! :) Cap'n. Bob '60 :{) PilotRob@... 23981... MORE
