Fu-Leng Posted September 28, 2011 Report Share Posted September 28, 2011 Hi all I have a Corolla KE35, but swapped the engine with a 4K (the 3K-B was stuck), and I?m having trouble to put the engine working. I'm using the carbs from the 3K-B (so 2 carbs), because I don't have a new inlet manifold for just 1 carb. If I drop a litle bit of fuel into the carbs, the car starts at first, but after a few seconds it goes out (same thing if I accelerate). Now I already took of the carbs and cleaned the internal. I think they don't get enough fuel to keep up running, so I tried to do the test of the fuel pump (this one is the 4K fuel pump), and while revving the starter for about 30 seconds I got about 30cl of fuel to a bottle (about half of a 0,5 liter bottle). Is this the correct debit of fuel for 1 carb? I have the workshop manual for the 3K engine and the fuel pump for the 3K sends the double of the fuel. Today I'll try to swith the fuel pumps, to see the difference. Can anyone confirm if the 2 fuel pumps are so different? I would appreciate. BR Quote Link to comment Share on other sites More sharing options...
GJM85 Posted September 28, 2011 Report Share Posted September 28, 2011 (edited) Those little fuel pumps move more than enough fuel. It could be over fueling. The 3k-b engine came with twin carbs and produced more power than a standard 4k engine due to a better camshaft, larger intake ports and a higher compression ratio.... Edited September 28, 2011 by GJM85 Quote Link to comment Share on other sites More sharing options...
Fu-Leng Posted September 28, 2011 Author Report Share Posted September 28, 2011 (edited) Thanks for the fast response. So I should try to use the Mixture screws on the carbs, right (the little ones on the bottom). Clockwise is less fuel and the other way more fuel, right? Or am I wrong? I'll need them to balance the carbs. Or do you think that the problem might be related with the fuel bowls on the carbs? Maybe the float is not regulated correctly? I did open the carbs and checked the floats, and tried to regulate it to the specs on the manual (about 6mm from the base while upside-down, and about 1mm from the needle if straight up). But if the problem is with the floats I can open them again and try to use lower values. Edited September 28, 2011 by Fu-Leng Quote Link to comment Share on other sites More sharing options...
woteva Posted September 28, 2011 Report Share Posted September 28, 2011 Hi all I'm using the carbs from the 3K-B (so 2 carbs), because I don't have a new inlet manifold for just 1 carb. BR Do these carburetors have electric cut out solenoids on them? are they connected? Quote Link to comment Share on other sites More sharing options...
altezzaclub Posted September 28, 2011 Report Share Posted September 28, 2011 If I drop a litle bit of fuel into the carbs, the car starts at first, but after a few seconds it goes out (same thing if I accelerate). So, if you make it rich by pouring in fuel, it starts, but when it has used that fuel it dies.... Is that right?? Does it idle? Can you drive it down the road? So far it sounds like not enough fuel, so blocked jets, an air leak, or similar. The slower fuel pump will still full the bowls enough to run it without driving, that takes very little fuel. Quote Link to comment Share on other sites More sharing options...
Fu-Leng Posted September 28, 2011 Author Report Share Posted September 28, 2011 Do these carburetors have electric cut out solenoids on them? are they connected? No solenoid on them (old 3K-B didn't have them). So, if you make it rich by pouring in fuel, it starts, but when it has used that fuel it dies.... Is that right?? that's correct. If I try to accelerate they also die. Does it idle? Can you drive it down the road? So far it sounds like not enough fuel, so blocked jets, an air leak, or similar. The slower fuel pump will still full the bowls enough to run it without driving, that takes very little fuel. it doesn't idle, so I can't test it on the road. So the problem might be on the carbs, right? Quote Link to comment Share on other sites More sharing options...
Spencer[RL] Posted September 28, 2011 Report Share Posted September 28, 2011 Sounds like something in the fuel delivery process . Quote Link to comment Share on other sites More sharing options...
altezzaclub Posted September 28, 2011 Report Share Posted September 28, 2011 Definitely sounds like fuel delivery. So, when you opened up the carbs were they full of fuel? Quote Link to comment Share on other sites More sharing options...
Fu-Leng Posted September 28, 2011 Author Report Share Posted September 28, 2011 Definitely sounds like fuel delivery. So, when you opened up the carbs were they full of fuel? When I opened them they had fuel, but before i opened I turned upside down to let the fuel out (by the 2 top tubes). I should try to crank the engine, and after that open the carbs to check if they are full. The first thing I thought was that the fuel pump was not delivery enough fuel (even the fuel filter stays almost empty). I'll try to do a test with a bottle of fuel, hanged high and dropping fule directly to the inlet of the carbs, to see if they keep going. If that works then the problem should be on the pump. Quote Link to comment Share on other sites More sharing options...
GJM85 Posted September 28, 2011 Report Share Posted September 28, 2011 (edited) I'd still be concerned with over fuelling. Sometimes what appears to be a lean condition is actually rich. The 4k ran on one carby, the 3k-b ran on two. It's about manifold vacuum. A 3k moves, let's say 133cfm and the 4k moves 148cfm. The thottle body size hasn't increased so air flow is restricted at idle increasing maniflod vacuum. The same amount of air will pass through the carb but the extra vacuum draws on the fuel delivery system increasing the mixture to a rich condition. So yes the air mixture would be the problem. You really should get the car on a dyno, but... Check for vacuum leaks firstly. Are all vacuum lines connected? Dizzy? PCV? Wind the air mixtures in until they seat, very softly. Wind them 1/2 a turn out Wind the idle speed screws out and then back in until they contact the throttle linkage. Start the engine. If it idles, you're getting somewhere. Edited September 28, 2011 by GJM85 Quote Link to comment Share on other sites More sharing options...
Fu-Leng Posted September 28, 2011 Author Report Share Posted September 28, 2011 (edited) I'd still be concerned with over fuelling. Sometimes what appears to be a lean condition is actually rich. The 4k ran on one carby, the 3k-b ran on two. It's about manifold vacuum. A 3k moves, let's say 133cfm and the 4k moves 148cfm. The thottle body size hasn't increased so air flow is still restricted at idle. The same amount of air will pass through the carb but the extra vacuum draws on the fuel delivery system increasing the mixture to a rich condition. So yes the air mixture would be the problem. You should get the car on a dyno. Check for vacuum leaks firstly. Are all vacuum line connected? Well, I believe there are only 2 vacuum lines - one from distributor to carb, and on from manifold to brake master cylinder (they are both connected). There is also another inlet from the valve cover connected. Wind the air mixtures in until they seat, very softly. Wind them 1/2 a turn out Clockwise or anticlockwise? I mean if I rotate the screw clockwise to the max it will get more air or less? The idle is around the 800rpm, right? BR Edited September 28, 2011 by Fu-Leng Quote Link to comment Share on other sites More sharing options...
GJM85 Posted September 28, 2011 Report Share Posted September 28, 2011 clockwise will close off the air mixture. Anti" will increase the mixture. Quote Link to comment Share on other sites More sharing options...
Fu-Leng Posted September 28, 2011 Author Report Share Posted September 28, 2011 Well, in my lunch break I took some time and went home to try the mixing screws (this what you get if you work near home). I turned them clockwise to the max, and then 1/2 anti-clockwise. The engine started, and stopped after some 3 seconds. Then I turned 1/2 again anticlockwise and this time the engine stays like almost 10 seconds working, and then dies, but if I try the throttle it will die. I'll play a little bit more with the screws tomorrow to see if I can get the engine to idle. Quote Link to comment Share on other sites More sharing options...
GJM85 Posted September 29, 2011 Report Share Posted September 29, 2011 Well, in my lunch break I took some time and went home to try the mixing screws (this what you get if you work near home). I turned them clockwise to the max, and then 1/2 anti-clockwise. The engine started, and stopped after some 3 seconds. Then I turned 1/2 again anticlockwise and this time the engine stays like almost 10 seconds working, and then dies, but if I try the throttle it will die. I'll play a little bit more with the screws tomorrow to see if I can get the engine to idle. mixture screws out 1 full turn and idle speed screws in 1/2 a turn from first contact... Quote Link to comment Share on other sites More sharing options...
Fu-Leng Posted October 14, 2011 Author Report Share Posted October 14, 2011 Well. After some day without working on the car I returned. Switched the 4K fuel pump for a 3K fuel pump, and i got the same problem, so the problem was not from the pump. Then I remembered that when I installed the engine the intake gaskets where not very good. So I took off the carbs, then the 2 manifolds. I re-installed the manifolds but without the gaskets (instead used a sealant). Now the engine keeps working if I accelerate a bit. When it tries to idle it dies. Then I saw that there was fuel dripping from one of the barrels on one carb. Now I think that maybe the seals on the carbs are not good or the float level needs to be adjusted. I'll try to do that this weekend. Thanks for everything! :) Quote Link to comment Share on other sites More sharing options...
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