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Oil leak? High Idle?

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Falkon

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A few weeks ago finally got to the point in which i could start my Midget for the first time. Now that its running the next list of problems are starting to arise, as expected. Now with the electronic ignition installed, im sure my timing is not exact but close. The engine is idling at about 2k to 2.5k. After a bit it will lower to 1.5, any lower and it begins to misfire to often and die. I think the problem may be the combination of the carbs needing adjusting, the oil that im burning from some place and the timing being off. Otherwise its not over heating and it seems to be running strong. Any suggestions on what i should work on next or look into. Also what should my oil pressure be sitting at. Currently its hovering around 70-80 with the high rpm.
 
The high idle speed will cause the timing to be advanced, as it needs to be set a a much lower speed. See if you can adjust the timing, even if just manually turning the distributor until you get the best idle. Remember to adjust both idle screws. Oil pressure is fine.
Make sure the pistons are free to move up and down using the little push rod underneath (engine off).then verify that both carbs are operating together at idle, i.e. that both pistons go up and down together and do not stick.
If all that works, write back
Scott in CA
 
Make sure there is oil in the piston dampners first then follow Scotts advise.

Kurt.
 
70-80 PSI oil pressure!? :shocked:

Can I borrow a few pounds? :jester:


Check for vacuum leaks as well.
 
Got to have the ignition and valves right then check for vacuum leaks before messing with the carbs. Otherwise you just end up chasing your tail.
 
Got all your vacumn hoses hooked up? I've found that when an engine doesn't idle but runs well above 2000rpm then there is a vacum leak somewhere by the carbs. Spray some starting fluid around the intake manifold and the carbs and see if the rpm automatically rises. Rig up a straw for the nozzle so you can avoid any ether entering the system through the air cleaners. I even taped some lenghths of PVC pipe to the intake throat of the carbs to assure the test ether was not entering at that point. Barring any other problem, I've done it lots of times and it works. Bayless is right, you can go around in circles.
 
I definitely do have a vacuum leak. I still haven't hooked up one of the vacuum lines because my local auto stores don't have the necessary connectors. Valves are knew and have been seated properly. I might pull the head off just to be double sure. As for the carbs, they have been completely rebuilt and the pistons do move smoothly up and down. With doing some looking around i think the carbs may be also running a bit rich. Ill get that Y vacuum connection that goes in between the carbs and go from there.
 
Get the vacuum connections done. It'll never run right with a significant vacuum leak.
 
All the vacuum lines are now connected and good. No leaks. It now seems to be running a bit smoother and the white smoke has gone away, but its still running at a high idle and still misfiring when i choke it down. At this point i think its a matter of adjusting the carbs. I do know they are running rich. Lifted the pistons up a bit and the idle speed up. Only thing is i really dont know how to properly adjust them. I know this is a process that needs to be done correctly. Does anyone have a good guide that i could use, or a video online? Tips and pointers would be helpful. Thanks everyone!
 
each carb has a nut on the bottom (with the needle) to make it leaner, turn the nut anti clockwise. richer, clockwise. typically you would turn one "flat" at a time ( 1/6 of a turn)
 
JP, that may be a little confusing.....
What JP says is correct, looking from the top of the SU.
Normally we think of the nut as you look at it from the bottom up, which means clockwise is leaner, and counter-clockwise is richer.
Scott in CA
 
thanks Scott. you're right - from the top
 
So, When looking down, to the Right, Richer, --They both start with R,
and to the Left, Leaner, ---they both start with L. ... but being British, it's on the wrong side, so backwards...

Nice Mnemonic.
 
Lots of info out there on balancing SU's. First make sure both butterflys are opening at exactly the same time. Oil in dashpot dampners then adjust the jets so that when raising the lifting pins the engine does not continue to increase in speed but just begins to level off or falter as the pin reaches its upper limit.
You really need a good manual to get a more complete description.

Kurt.
 
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