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Discussion Starter #21
No.. please change the oil now before startup. Gas is a not a lubricant at all. If you can smell it in the oil, then it is too much. There is no good reason to take a chance with a new engine. If you put a little bit of oil in the cylinders now, that is to replace the oil on the cylinder walls that got washed off by the gas. I would run a compression test; I am not sure it is important if you do it now.

Keep your ear open for knocking (detonation) when you get up to middle RPM's and wide open throttle on the road tests. Do you know at what RPM's the advance reaches the full 36 degrees?
Yes that’s what I meant. I’ll change it now and then start it up, and then change again to make sure there is no fuel left. Have already put in oil in the cylinders and turned the engine one round.
I will :) As for what I have read around 3000 should be the target but I will have to test at see how I works. I just took a light spring from an other distributor, so I will have to test and see how it goes.
Again, thanks for all the help.


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Discussion Starter #22
I think that the height of the posts that the floats pivot on might be different, although that might only apply to the newer DCOE's. I ran across this problem when I swapped the cover from my DCOE9 with one from the latest DCOE 132(I think). I really hate those plastic floats, they fit too tight and you have to be really careful removing the lids.
That’s good information. I was thinking to replace them with plastic one to make sure it did not happen again but if the old type is better then I’ll stick to these.


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Discussion Starter #23
  • 5-7 volts sounds reasonable.
  • Measure the spark plug wires for resistance end to end. If they are standard resistance wires, then in the range of 3,000 to 7,000 ohms is to be expected. Checked to see if you have a loose end on that #4 wire.
  • To check spark, place the end of the spark wire from the coil about 6-8 mm from a metal surface, crank the engine, and look for a good blue spark to jump that gap in open air.
  • If you have a compression gauge, I would check all cylinders for cranking compression.
  • What sized cam do you have? 12.5 compression ratio is too high for a standard stock cam and even 98 octane fuel. (European octane when is the Research octane number).
  • Do you have a solid lifter cam?
  • The fact that both cylinders 3 and 4 are showing problems suggests that something may have changed or failed in that back carburetor.
I question for the experienced.
I now got it running pretty good. And some road testing showes that it runs pretty good after some adjustment of the carb and dizzy. BUT, when I fill up my radiator it will spit out a lot of it. When having the cap off while hot, I see that it does not seem to bubble, but after Reving there is quite a lot of overflow and it seems to burp sometimes. The engine does not get hot so i just want to verify if it spits out the coolant because of overflow or over pressure as I’m still a bit concerned that head gasket could have been damaged with a the fuel dripping in to the cylinder. But I will try to install a pressurised expansion tank to see it there will build up over pressure.
Do you have any experiences with this?



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The older non-overflow type of radiators need to have an air gap in the top of the radiator; that is the expansion volume for the coolant as it get hot. What you show in the pix is about the highest you can run the coolant when cold and sitting on level ground; it ought to run at about 3/4" to 1" of an inch below where the rad cap seals. If you try to fill it up more, then it will just expand and puke out the overflow hose when the coolant heats up.

As it heats up and with the cap off and idling, it is normal for the coolant to rise in the neck. And if you rev it, the level will tend to surge. At this point I would not take those as points of concern. Gas down the cylinders would not damage the head gasket. And 'not heating up' is not a symptom of a bad head gasket, it would tend to do the opposite.

You need to put the cap on and proplery tighten it and drive the car to get it warmed up; and then let it cool, and re-check the coolant level. Do this a few times and see if the coolant level stabilizes after a few heat cycles. It often takes 2-3 cycles to clear out all the air pockets.

What makes you say that the engine does not heat up? Is there no indication on temp gauge? That could be a faulty temp gauge. Ideally, you would borrow a temp gun and look at the upper rad hose right where it comes out of the thermostat housing and see it at something like 170-175 degrees F when the engine is warmed up. Lacking that, you ought to touch the upper rad hose (Carefully! Watch out for the fan!) after the engine has run a while and ought to be very hot, as well as the upper tank on the rad. Those being good and hot shows that the t'stat has opened.

If the engine is truly cool, then the 1st suspect is the thermostat being open all the time. Pull it out, and use the simple test of heating it in water on the stove to see if it opens at about the right temp. And make sure it gets installed in the right direction.

If you do go with a coolant recovery type of system, then the cap has to be changed to a different type. But I would not put that on yet, untill you have driven it several heat cycles to see if you have the coolant level stablizes as described above the stock system. No need to mask a problem, if there is any.

At some point, after a couple of heat cycles, I like to re-torque the head bolts.

And like JHJ, I am curious as to what all it took to fix the seemingly dead cylinder.
 

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Discussion Starter #26
No clue on the radiator issue.

I’m curious what you did to get it running better and back in all 4 cylinders?
I had a punctured float in the carburettor on cylinder 3-4, so the carb kept topping up fuel that dripped in to the cylinder, see post #14. As a temp fix i emptied the float thru the entry hole and glued it with 2k glue. Worked pretty well and the fuel level is ok.. I actually just got the new floats today and I’m changing both to be sure


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Discussion Starter #27
The older non-overflow type of radiators need to have an air gap in the top of the radiator; that is the expansion volume for the coolant as it get hot. What you show in the pix is about the highest you can run the coolant when cold and sitting on level ground; it ought to run at about 3/4" to 1" of an inch below where the rad cap seals. If you try to fill it up more, then it will just expand and puke out the overflow hose when the coolant heats up.

As it heats up and with the cap off and idling, it is normal for the coolant to rise in the neck. And if you rev it, the level will tend to surge. At this point I would not take those as points of concern. Gas down the cylinders would not damage the head gasket. And 'not heating up' is not a symptom of a bad head gasket, it would tend to do the opposite.

You need to put the cap on and proplery tighten it and drive the car to get it warmed up; and then let it cool, and re-check the coolant level. Do this a few times and see if the coolant level stabilizes after a few heat cycles. It often takes 2-3 cycles to clear out all the air pockets.

What makes you say that the engine does not heat up? Is there no indication on temp gauge? That could be a faulty temp gauge. Ideally, you would borrow a temp gun and look at the upper rad hose right where it comes out of the thermostat housing and see it at something like 170-175 degrees F when the engine is warmed up. Lacking that, you ought to touch the upper rad hose (Carefully! Watch out for the fan!) after the engine has run a while and ought to be very hot, as well as the upper tank on the rad. Those being good and hot shows that the t'stat has opened.

If the engine is truly cool, then the 1st suspect is the thermostat being open all the time. Pull it out, and use the simple test of heating it in water on the stove to see if it opens at about the right temp. And make sure it gets installed in the right direction.

If you do go with a coolant recovery type of system, then the cap has to be changed to a different type. But I would not put that on yet, untill you have driven it several heat cycles to see if you have the coolant level stablizes as described above the stock system. No need to mask a problem, if there is any.

At some point, after a couple of heat cycles, I like to re-torque the head bolts.

And like JHJ, I am curious as to what all it took to fix the seemingly dead cylinder.
Okay. That’s good information.
For now I planned to take a 160 thermostat and drill a 3 mm hole to make it easier to get the air out. And test again. The problem has been that it spits out the coolant so I have not managed to keep the level Up arround the cap, when I fill up like in the picture then I would take it for a drive and it would spit out like 300ml (0,31qt) so I am never able to keep the level up so I can see it in the cap hole. That’s why I wanted to drill a little bleed hole to make sure the problem is not air in the system. Sorry for the bad explanation about the picture.
What I meant about it not heating up is that it is not getting too hot it is keeping the temp fine arround 170-180.
I tried to take the pressure off while the engine was hot so the hoses was all punctured, I then took a drive and when I checked the hoses again they where pretty hard again, is this normal? I am thinking that the air can not expand more so it can only be due to steam or something not good.?


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Very good explanation on the problem with the float. Glad you fixed that.

I think I understand your info above. If you fill this type of cooling system too much, then it will always spit out some coolant. You need to fill when cold, and with the car sitting on level ground, until the coolant is about 20-25 mm below the edge of the radiator cap. Do not fill higher than that out or the excess will be spit out. In your first 2 or 3 drives, the air in the system will collect in the radiator top tank, and so you will have to add a bit each time for a few heat cycles of the system. There is ALWAYS some air in this type of older system with no overflow recovery tank. The air expands AND the coolant expands; anti-freeze mix expands with heat by 3-4% with temperature change from 20C to 80C.

You may also have a faulty radiator cap that is releasing pressure at too low a pressure when hot. It is easy to try another radiator cap. OK on the 170-180F running when hot; that is a good number and sounds normal.

The hoses getting harder again after you released the pressure when hot is OK. If you relase the pressure when hot, it is going to build up again when you close the system. It may boil a little bit inside (like in the head, where it is the hottest), but the pressure will build up and then the boiling will slow down or stop. When the system cools down, then the coolant and air inside will contract, and in your case, will eventually form a vacuum in the radiator. The cap should open with some vacuum and allow air into the system to compensate.
 

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And if you eventually want to check to see if the head gasket is leaking into the coolant, then there are tools to do that. One is a chemical that you add to the coolant; it shows a color change in the presense of carbon dioxide. The other is a pressure gauge built into a radiator cap; you install that in the palce of the radiaoro cap, let the engine get hot and watch the pressure build. The pressure should be constant and not vary; if there are pressure pulsations on the gauge when hot, then there is a head gasket leak, or a crack in the block or head.

But I think you need to let the coolant level stablize in the system first... and make sure that you do not overfill the radiator when cold.
 

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Discussion Starter #30
Very good explanation on the problem with the float. Glad you fixed that.

I think I understand your info above. If you fill this type of cooling system too much, then it will always spit out some coolant. You need to fill when cold, and with the car sitting on level ground, until the coolant is about 20-25 mm below the edge of the radiator cap. Do not fill higher than that out or the excess will be spit out. In your first 2 or 3 drives, the air in the system will collect in the radiator top tank, and so you will have to add a bit each time for a few heat cycles of the system. There is ALWAYS some air in this type of older system with no overflow recovery tank. The air expands AND the coolant expands; anti-freeze mix expands with heat by 3-4% with temperature change from 20C to 80C.

You may also have a faulty radiator cap that is releasing pressure at too low a pressure when hot. It is easy to try another radiator cap. OK on the 170-180F running when hot; that is a good number and sounds normal.

The hoses getting harder again after you released the pressure when hot is OK. If you relase the pressure when hot, it is going to build up again when you close the system. It may boil a little bit inside (like in the head, where it is the hottest), but the pressure will build up and then the boiling will slow down or stop. When the system cools down, then the coolant and air inside will contract, and in your case, will eventually form a vacuum in the radiator. The cap should open with some vacuum and allow air into the system to compensate.
Okay. I get more and more relaxed.. :D
I think I getting a bit closer.. it will still spit out the coolant until I can’t see it in the radiator hole, BUT it came to my mind that I changed the angle of the engine in order to have space for the Weber’s and that have raised the thermostat housing by 3/4 inch (2cm) couldn’t that raise the level in the radiator, so that would be why it spits out the top of the coolant?

.. hmm think I will make a catch can to monitor the amount that is spit out..


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That is a very interesting matter. I just looked at my Ascona A and the bottom of the radiator filler is about 40 mm higher than the top of the thermostat housing. I am 99% sure your situation would make the system more prone to spitting out fluid. It looks like you will have to go to an overflow system as the air expansion space in the top of the radiator is now too low.
 

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Discussion Starter #32
That is a very interesting matter. I just looked at my Ascona A and the bottom of the radiator filler is about 40 mm higher than the top of the thermostat housing. I am 99% sure your situation would make the system more prone to spitting out fluid. It looks like you will have to go to an overflow system as the air expansion space in the top of the radiator is now too low.
Thanks for the measurement. Seems like it is starting to make sense I was actually thinking about buying an aluminium cylindric expansion tank that can be placed where the sprinkler tank normally is. Then I could have that raised above the rad and have that as the main expansion space. Wouldn’t that be at better solution than overflow or am I wrong?


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That could work too. But the overflow system, with a proper radiator cap that is a more modern way to do it. And it will eventually purge out the air.

But, for that, I think the radiator cap still has to be at the highest point. Or you need a point at the higher spot to bleed out the air. Some of the guys here have installed an air bleed on the top of the t-stat housing when it is a high spot. So maybe your expansion tank up high with a separate pressure cap on it is easier.
 

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Discussion Starter #34
That could work too. But the overflow system, with a proper radiator cap that is a more modern way to do it. And it will eventually purge out the air.

But, for that, I think the radiator cap still has to be at the highest point. Or you need a point at the higher spot to bleed out the air. Some of the guys here have installed an air bleed on the top of the t-stat housing when it is a high spot. So maybe your expansion tank up high with a separate pressure cap on it is easier.
Yeah. I will try to get a eBay expansion tank and get it up over the rad.. thanks for all the advice.

Finally got my new floats in. It seems like the 2k glue reacted with the fuel so I’m happy to ha e the new ones in now :) .



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Had a very similar sporadic issue like this on a 2007 Corsa B out of the blue suddenly. Engine was running quite rough backfiring occasionally, with an obvious loss in engine power. Drove back from Langebaan to Cape Town stopping occasionally to prevent engine over-heating just as a basic precaution. Turned out the solenoid had burnt out and after replacing it everything was 100's again.

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Discussion Starter #36
Had a very similar sporadic issue like this on a 2007 Corsa B out of the blue suddenly. Engine was running quite rough backfiring occasionally, with an obvious loss in engine power. Drove back from Langebaan to Cape Town stopping occasionally to prevent engine over-heating just as a basic precaution. Turned out the solenoid had burnt out and after replacing it everything was 100's again.

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What solenoid ? It doesn’t some like one that is present on my GT?


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What solenoid ? It doesn’t some like one that is present on my GT?


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He's talking about a 2007, so probably doesn't apply to a our GTs
 
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