Hopefully someone can help me with this problem. I have a 1300S Zagato that runs very well. Except when the engine is warm (afetr some time on a highway for instance), I experience gradual power loss but the power comes back after a while. If I drive slower, the problem seems to be smaller. Otherwise the engine runs very well and smooth. I suspect there may be a fuel problem, perhaps vapour lock or a fuel pump problem. I have read about people that have fitted an electric fuel pump. Could this be the answer?
Thanks,
Guus
Power loss in warm engine
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ese
Re: Power loss in warm engine
I do have the same problem. Have you been able to solve your problem? Please kindly send me info if you were sucessful in solving the problem. I am going crazy myself. My e-mail is : eseoku@hotmail.com
Looking forward to hearing from you.
Thank you.
Ese
Looking forward to hearing from you.
Thank you.
Ese
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Guus Keder
Re: Power loss in warm engine
No, I have not been able to solve the problem yet. It has not been very warm so far, so the problem has not bothered me too much, but needs fixing at some point. Some people suggested changing the fuel filters. We have not done that yet but will try. They look OK, but perhaps that's worth trying. I have discussed the problem extensively with the mechanic who maintains my car and we have concluded that it is most likely a fuel problem.
Hope this helps.
Guus
Hope this helps.
Guus
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michel
Re: Power loss in warm engine
Try once with a compressor to clean the filters of the two carbs Solex. For this, take up the "durite" on the two holes containing the filters and take up too these filters (to clean with fuel, of course!).
Also, turn towards these holes compressing air while a few seconds. It's possible that force out anyone impurity.
Good luck and regards.
Michel (Belgium, 1300s Mark II 1972 very reliable !)
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Huib Geurink
Power loss in warm engine
Hi Guus,
Sorry for the late reply. I just noted the problem as I received a copy of Michel's posting.
If an engine gets the right fuel /air mixture and a good spark at the right time, it will run well. It is as simple as that.
Although it sounds like a fuel problem, I would still start working on and checking the ignition, just because it is simple to make sure it is 100% all right. And it has to be good anyway.
Start changing the condenser. A bad condenser also results in funny behaviour much like you describe. Condensers should actually be changed every two years. It is a low cost part. Its value when new is 2.5 microfarad. The value decreases over time.
Make sure the ignition's fixed advance is at 8 degrees. You don't say whether you have a S1 or a S2 car. On the S1 cars the timing marks on the flywheel are often very difficult to find. There is no mark for the fixed advance. There is only one tooth with a by now unreadable 0 indicating TDC. Find that tooth and mark it with white paint. I always put a screwdriver through spark plug hole #1 to feel / see the highest point of piston #1. The movement of the piston is a sinus. So the top of the movement is a bit flat. You need very sensitive fingers / palm / eyes to determine TDC. Repeat the process several times to absolutely make sure you have the right tooth. With a very strong flashlight you may actually be able to see a mark which once may have been a 0. As I said, make it white. Then paint the 3rd tooth towards the oil fill canister red. This is your mark for the ignition advance. It is actually a bit more than 8 degrees, but you should be all right with the good quality petrol in Belgium.
On S2 cars it is easier. There are easy to read marks for TDC and the advance on the flywheel.
Make sure you have good quality contact breakers. Adjust them to a maximum opening of 0.45mm. Double check by trying feeler 0.50. This one should not be able to go through. Feeler 0.40 should go through easily.
Set the ignition so that the points open at exactly the mark for the advance ignition. I connect a screwdriver with a light bulb between the - terminal of the ignition coil and the - of the battery, put the key on the dashboard / steering column in the "run" position and turn the crankshaft with spanner 24 on the nut of the crankshaft pulley. When the light goes on, the mark for the advance ignition should be in the center of the window. If not rotate the ignition unit till it does.
Put NGK BP7ES spark plugs with the gap set to 0.6mm or BPR7EIX with the gap as set by the factory. Never change the gap on the BPR7EIX as you will break the electrode. Check cables, distributor cap, rotor and the contacts of the ignition coil and clean if necessary. Don't use anything else than NGK plugs. They are very good. All others are #$%^
When the ignition is properly set, start the engine and let it idle at 800 rpm. Use a strobe light to observe the ignition mark. It should be reasonable steady. Operate the throttle by hand. The ignition mark should move smoothly in the direction of the battery. When you return to an idle of 800 rpm, the mark should also return to the centre of the window again. Play a bit with the throttle and observe the behaviour of the mark untill you are 100% confident the ignition advance works smoothly. If the behaviour is erratic or if the mark oscillates wildly you have a problem. We can deal with that if it occurs.
There is a bit of controversy about the right dwell angle. Some say it has to be between 55 and 60 degrees. I have used this value untill recently but I find my cars start and run better with a dwell angle closer to 50.
Once the ignition is 100%, check the fuel supply. The mechanical fuel pumps are very good, very effective and very reliable. If it is still the original pump it is suspect because of old age, but no need to change if it still operates efficiently. It is wise to have a spare one in the boot though. The fuel pump has two small valves which are tiny membranes with a small spring. If there is dirt inside which prevents them from closing, the pump quickly looses efficiency. If you don't consider it the right moment to replace the pump, then clean the pump. But also make sure, no more dirt gets to the pump. There should be absolutely no dirt in the pump nor the carburettors. If there is, you have to look for the source and make 200% percent sure dirt is kept out of those parts from now onwards.
My Appia once suffered a similar problem and finally gave up all together. This was in Luxembourg. Jan Van Hoorick found us and trailered us to Houffalize where we solved the problem by cleaning the carburetor, pump, fuel lines and tank. The tank was full of brown stuff said to be a left over from the LRP (lead replacement fuel). The filter at the bottom of the tank had desintegrated. The fuel line was blocked solid. The fuel line runs down from the tank, under the car bottom and comes up again in the engine compartment. It forms a goose neck. If I was given the task of designing a fuel line which clogs easily, I would design it exactly like that.
Insert a plastic fuel filter before the fuel pump. If it still has an original glass filter, remove it. These filters have a pressure regulator, which gets clogged and will the also produce the effect you describe (as was the case in my Flavia).
If you have a big dirt problem, you should clean the tank, replace the filter at the bottom, replace or thoroughly clean the fuel lines as well as insert the plastic filter before the pump. Cleaning the fuel lines should be done by blowing compressed air through it. Alternate several times blowing from the front and from the rear. By the rear I mean really from the rear. Remove plug and filter from the bottom of the tank and press the air gun to the start of the fuel line at the bottom of the tank.
If you do a temporary job in cleaning the fuel line and only blow from the front, remember to at least take the filler cap off to let the air out of the tank. Remember though that you blow all the dirt right back into the tank. It will come back into the system as the filter at the bottom of the tank is gone. If the filter would still be there you would not have had the problem to begin with.
And of course as Michel says, clean the filters in the carbs. These filters may have desintegrated too. The carbs may be dirty themselves. If you have a plastic filter in front of the pump, you don't need filters in the carbs.
Don't underestimate a dirt problem. It will keep haunting you unless it is eliminated thoroughly and completely.
An electric pump is not necessary. The disadvantage of an electric pump is that it keeps pumping after an accident as long as the contact switch is on, even if the engine is wrapped around a tree. Some people install electric pumps to fill the carbs quickly with petrol without using the starter motor when the carbs are empty after not using the car for some time. It is not necessary. If the mechanical pump is 100% efficient and the fuel lines and filters are clean, the carbs will be full in a few seconds of cranking the engine. If it takes too long, it often is the first sign that dirt is coming the wrong way. Better solve the problem by eliminating the cause, rather than mask it.
Sorry for the late reply. I just noted the problem as I received a copy of Michel's posting.
If an engine gets the right fuel /air mixture and a good spark at the right time, it will run well. It is as simple as that.
Although it sounds like a fuel problem, I would still start working on and checking the ignition, just because it is simple to make sure it is 100% all right. And it has to be good anyway.
Start changing the condenser. A bad condenser also results in funny behaviour much like you describe. Condensers should actually be changed every two years. It is a low cost part. Its value when new is 2.5 microfarad. The value decreases over time.
Make sure the ignition's fixed advance is at 8 degrees. You don't say whether you have a S1 or a S2 car. On the S1 cars the timing marks on the flywheel are often very difficult to find. There is no mark for the fixed advance. There is only one tooth with a by now unreadable 0 indicating TDC. Find that tooth and mark it with white paint. I always put a screwdriver through spark plug hole #1 to feel / see the highest point of piston #1. The movement of the piston is a sinus. So the top of the movement is a bit flat. You need very sensitive fingers / palm / eyes to determine TDC. Repeat the process several times to absolutely make sure you have the right tooth. With a very strong flashlight you may actually be able to see a mark which once may have been a 0. As I said, make it white. Then paint the 3rd tooth towards the oil fill canister red. This is your mark for the ignition advance. It is actually a bit more than 8 degrees, but you should be all right with the good quality petrol in Belgium.
On S2 cars it is easier. There are easy to read marks for TDC and the advance on the flywheel.
Make sure you have good quality contact breakers. Adjust them to a maximum opening of 0.45mm. Double check by trying feeler 0.50. This one should not be able to go through. Feeler 0.40 should go through easily.
Set the ignition so that the points open at exactly the mark for the advance ignition. I connect a screwdriver with a light bulb between the - terminal of the ignition coil and the - of the battery, put the key on the dashboard / steering column in the "run" position and turn the crankshaft with spanner 24 on the nut of the crankshaft pulley. When the light goes on, the mark for the advance ignition should be in the center of the window. If not rotate the ignition unit till it does.
Put NGK BP7ES spark plugs with the gap set to 0.6mm or BPR7EIX with the gap as set by the factory. Never change the gap on the BPR7EIX as you will break the electrode. Check cables, distributor cap, rotor and the contacts of the ignition coil and clean if necessary. Don't use anything else than NGK plugs. They are very good. All others are #$%^
When the ignition is properly set, start the engine and let it idle at 800 rpm. Use a strobe light to observe the ignition mark. It should be reasonable steady. Operate the throttle by hand. The ignition mark should move smoothly in the direction of the battery. When you return to an idle of 800 rpm, the mark should also return to the centre of the window again. Play a bit with the throttle and observe the behaviour of the mark untill you are 100% confident the ignition advance works smoothly. If the behaviour is erratic or if the mark oscillates wildly you have a problem. We can deal with that if it occurs.
There is a bit of controversy about the right dwell angle. Some say it has to be between 55 and 60 degrees. I have used this value untill recently but I find my cars start and run better with a dwell angle closer to 50.
Once the ignition is 100%, check the fuel supply. The mechanical fuel pumps are very good, very effective and very reliable. If it is still the original pump it is suspect because of old age, but no need to change if it still operates efficiently. It is wise to have a spare one in the boot though. The fuel pump has two small valves which are tiny membranes with a small spring. If there is dirt inside which prevents them from closing, the pump quickly looses efficiency. If you don't consider it the right moment to replace the pump, then clean the pump. But also make sure, no more dirt gets to the pump. There should be absolutely no dirt in the pump nor the carburettors. If there is, you have to look for the source and make 200% percent sure dirt is kept out of those parts from now onwards.
My Appia once suffered a similar problem and finally gave up all together. This was in Luxembourg. Jan Van Hoorick found us and trailered us to Houffalize where we solved the problem by cleaning the carburetor, pump, fuel lines and tank. The tank was full of brown stuff said to be a left over from the LRP (lead replacement fuel). The filter at the bottom of the tank had desintegrated. The fuel line was blocked solid. The fuel line runs down from the tank, under the car bottom and comes up again in the engine compartment. It forms a goose neck. If I was given the task of designing a fuel line which clogs easily, I would design it exactly like that.
Insert a plastic fuel filter before the fuel pump. If it still has an original glass filter, remove it. These filters have a pressure regulator, which gets clogged and will the also produce the effect you describe (as was the case in my Flavia).
If you have a big dirt problem, you should clean the tank, replace the filter at the bottom, replace or thoroughly clean the fuel lines as well as insert the plastic filter before the pump. Cleaning the fuel lines should be done by blowing compressed air through it. Alternate several times blowing from the front and from the rear. By the rear I mean really from the rear. Remove plug and filter from the bottom of the tank and press the air gun to the start of the fuel line at the bottom of the tank.
If you do a temporary job in cleaning the fuel line and only blow from the front, remember to at least take the filler cap off to let the air out of the tank. Remember though that you blow all the dirt right back into the tank. It will come back into the system as the filter at the bottom of the tank is gone. If the filter would still be there you would not have had the problem to begin with.
And of course as Michel says, clean the filters in the carbs. These filters may have desintegrated too. The carbs may be dirty themselves. If you have a plastic filter in front of the pump, you don't need filters in the carbs.
Don't underestimate a dirt problem. It will keep haunting you unless it is eliminated thoroughly and completely.
An electric pump is not necessary. The disadvantage of an electric pump is that it keeps pumping after an accident as long as the contact switch is on, even if the engine is wrapped around a tree. Some people install electric pumps to fill the carbs quickly with petrol without using the starter motor when the carbs are empty after not using the car for some time. It is not necessary. If the mechanical pump is 100% efficient and the fuel lines and filters are clean, the carbs will be full in a few seconds of cranking the engine. If it takes too long, it often is the first sign that dirt is coming the wrong way. Better solve the problem by eliminating the cause, rather than mask it.