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Old 17th August 2010, 19:21   #151
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Originally Posted by DHABHAR.BEHRAM View Post
Dear Pavan - I suspected that water jacket leakage would occur when you had posted the photograph of the cylinder block open with the cylinder head gasket on it, but chose to keep my fingers crossed because I did not want to alarm you. I don't think the gasket in that condition will work. Please conduct root cause analysis and quietly work out the corrective action plan. You got a job on your hands now. Best of luck.

By the way, are the plugs firing?

Best regards,

Behram Dhabhar
Thank you sir,

Here are few things that i noticed, kindly decipher.

1) Engine starts and idles perfectly without radiator / water

2) With the radiator connected and water in it, the engine fires and dies down. (did not continue cranking fearing other damages)

3) All spark plugs are firing

4) The water jacket next to the valve door cover is leaking, which is a simple job to fix the leak.

5) But i am getting water droplets from 2nd and 4th sparkplug.

Have anyways abandoned the engine fire up.

We are going to dismantle the engine head again, trying the pressure test once again , and once opened we will now the root cause.

I feel disheartened, by the way all the excitement died down abruptly.

Lets hope for the best. I am not the one to give up.

Last edited by PAVAN KADAM : 17th August 2010 at 19:24.
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Old 17th August 2010, 22:12   #152
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Dear Pavan - water droplets on the spark plugs indicates that the compression is leaking into the jackets. If there is even a little water in the cylinders, the engine will not work. What is surprising is your comment that the engine idles perfectly without water in the radiator. This means that even if there is a leak, it is very minor. If there is a major compression leak, the engine will never idle properly. As a general rule, water in adjacent cylinders indicates a defective gasket joint between cylinders but it is not always the case. The gasket could have blown from 2 locations / the cylinder head may not be sitting flush on the cylinder block / it may be something even as minor as insufficient torque on the cylinder head nuts. What is the thread size? Is it M12? If it is 19 across flat socket, it is M12 and if it is 17 across flat socket, it is M10. If it is M12, you will need 8 kgm of torque (58 ft lb). Generally M10 is not used for cylinder head mounting but as this is a very small engine, you never know. For M10, I will have to refer to the standard sheet but it may be in the region of 5.5 kgm (40 ft lb). The head must be torqued in steps of 2 kgm, starting from the center, moving to both sides, then the final torque should be applied, then this torque should be slackened and reapplied on one by one nuts, to enable the gasket to take its final location. If you do this, you will notice that the torque wrench will rotate by at least 120 to 150 degrees from its loosening location at same torque. It is this additional procedure which makes all the difference. If you don't do this retorquing, the engine will not work properly. Also check the threaded length of the cylinder head mounting studs to completely eliminate the possibility of the nuts bottoming on the studs as you have reduced the deck height of the cylinder head by facing it. Bottoming of the nuts will give you a false reading of torque when actually it may not be so because the nut will not press down on the head as required by design intent. I hope you have done all this. If you have the workshop manual of the Topolino, please scan and post the relevant portions here, to enable me to guide you in totality. Please start the engine once again without water, listen to the compression noises very very carefully and let me know the detailed observations. Do not run the engine for more than 30 seconds at one time.

You may safely eliminate the possibility of the cylinder block warping. Generally cast iron blocks do not have this problem.

Besides above, if there is something that you finally find which eliminates this problem, please do let me know, I would then have learnt something more, because I will never stop learning.

Best regards,

Behram Dhabhar
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Old 19th August 2010, 01:27   #153
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Pawan,

what a nice information Mr. Behram has given. Just to add to it. Please make sure you after you hear the first click of the torque wrench, you go further until you hear the second.
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Old 19th August 2010, 20:08   #154
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Originally Posted by DHABHAR.BEHRAM View Post
Dear Pavan - water droplets on the spark plugs indicates that the compression is leaking into the jackets. If there is even a little water in the cylinders, the engine will not work. What is surprising is your comment that the engine idles perfectly without water in the radiator. This means that even if there is a leak, it is very minor. If there is a major compression leak, the engine will never idle properly. As a general rule, water in adjacent cylinders indicates a defective gasket joint between cylinders but it is not always the case. The gasket could have blown from 2 locations / the cylinder head may not be sitting flush on the cylinder block / it may be something even as minor as insufficient torque on the cylinder head nuts. What is the thread size? Is it M12? If it is 19 across flat socket, it is M12 and if it is 17 across flat socket, it is M10. If it is M12, you will need 8 kgm of torque (58 ft lb). Generally M10 is not used for cylinder head mounting but as this is a very small engine, you never know. For M10, I will have to refer to the standard sheet but it may be in the region of 5.5 kgm (40 ft lb). The head must be torqued in steps of 2 kgm, starting from the center, moving to both sides, then the final torque should be applied, then this torque should be slackened and reapplied on one by one nuts, to enable the gasket to take its final location. If you do this, you will notice that the torque wrench will rotate by at least 120 to 150 degrees from its loosening location at same torque. It is this additional procedure which makes all the difference. If you don't do this retorquing, the engine will not work properly. Also check the threaded length of the cylinder head mounting studs to completely eliminate the possibility of the nuts bottoming on the studs as you have reduced the deck height of the cylinder head by facing it. Bottoming of the nuts will give you a false reading of torque when actually it may not be so because the nut will not press down on the head as required by design intent. I hope you have done all this. If you have the workshop manual of the Topolino, please scan and post the relevant portions here, to enable me to guide you in totality. Please start the engine once again without water, listen to the compression noises very very carefully and let me know the detailed observations. Do not run the engine for more than 30 seconds at one time.

You may safely eliminate the possibility of the cylinder block warping. Generally cast iron blocks do not have this problem.

Besides above, if there is something that you finally find which eliminates this problem, please do let me know, I would then have learnt something more, because I will never stop learning.

Best regards,

Behram Dhabhar
Sir, after opening the cylinder head today, noticed something very funny.

1) The head is clean.
2) Gasket looks good
3) BUT.....! i see the water channel near the spark plug threads have opened up.

So gone back to the drawing board, now given the Head to the lathe guy and asked him to Fix It Again Thambi

Monday i will be getting the head back, so hopefully we will resume further work on the engine, And about the torque settings, Thanks for the readings sir.
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Old 26th August 2010, 18:57   #155
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Hmmmm..............!

One more exciting weekend on the cards..

The other head is ready and got it yesterday, the mechanic has kept every thing ready to mount it.

From tomorrow the countdown starts, i am jittery , Nervous, and all excited

Hope we get it right this time.
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Pilots & his 1950 Mouse Restoration - Fiat Topolino Delivered-imag_0783.jpg  

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Old 26th August 2010, 19:28   #156
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Hope that you are lucky this time and get the engine to work as it should. My best wishes accompany you.
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Old 26th August 2010, 19:37   #157
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Originally Posted by PAVAN KADAM View Post
Hmmmm..............!

One more exciting weekend on the cards..

The other head is ready and got it yesterday, the mechanic has kept every thing ready to mount it.

From tomorrow the countdown starts, i am jittery , Nervous, and all excited

Hope we get it right this time.
Well if you pressure test the head before refitting that would do the job for you. It would sprung out any leaks. Secondly for cracks you can use a dye penetrant to determine them. Stich welding is then required in these cases.

Last edited by manishalive : 26th August 2010 at 19:39.
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Old 28th August 2010, 22:32   #158
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Hi Pavan,

Hope the engine fires up with out any problem.

what colour are you gonna choose for the fiat? and when are you starting the painting work,see to that you do it before the rainy season starts (though nowadays we have paintbooth)
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Old 23rd September 2010, 00:38   #159
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Originally Posted by manishalive View Post
Well if you pressure test the head before refitting that would do the job for you. It would sprung out any leaks. Secondly for cracks you can use a dye penetrant to determine them. Stich welding is then required in these cases.
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Hi Pavan,

Hope the engine fires up with out any problem.

what colour are you gonna choose for the fiat? and when are you starting the painting work,see to that you do it before the rainy season starts (though nowadays we have paintbooth)
Hi guys,

I was totally distressed after the Head sprung a leak

And did not concentrate further on the engine.

Earlier to this, we overhauled the complete braking system of this car.

Installed new Brake pipes.

The wheel cylinders had rust, but the kits belonging to Fiat Uno suited well. So all the Wheel cylinders are now new.

Master cylinder also had issues, it was jammed, but since this mechanic had worked on many cars he was quick enough to repair it.

Got all the brake shoes redone and rivetted.

All the wheel drums were cleaned, brakes bleeded and the brakes are now perfect.

Engine head is getting a bit of attention these days, we are doing a pressure test to check the leakages, we are tapping them to close them. Maybe in next 10 days time, we will be able to get the Head repaired in perfect condition.

If nothing works, we will go in for a BRAND NEW HEAD from Italy.

Next week, the car will be sent for painting.

Will upload pics tomorrow.
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Old 23rd September 2010, 08:25   #160
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Another compond to arrest leaks is Belzona cold weld compound, it is costly but a good repair option.

Blow holes in Casted Engine Blocks are many times cured by this. All Generator engines components are definitely costlier to replace than to work with cold welding compound.

If you want more info I can get you the pricing and other details.

Last edited by .anshuman : 23rd September 2010 at 14:48. Reason: Please do not quote en entire large post, it causes inconvinience to our small screen and mobile users. Thanks
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Old 23rd September 2010, 23:07   #161
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Originally Posted by manishalive View Post
Another compond to arrest leaks is Belzona cold weld compound, it is costly but a good repair option.

Blow holes in Casted Engine Blocks are many times cured by this. All Generator engines components are definitely costlier to replace than to work with cold welding compound.

I would not recommend cold welding for this head. My suggestion is to use hot welding and then reface the head and only if it is a compression problem. Other wise I would do the same as Mr. Behram has said and also try and get the Workshop manual if you can. It does wonders at times.

Best of luck and keep us posted on the happenings.
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Old 23rd September 2010, 23:39   #162
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I would not recommend cold welding for this head.
Well there are two kinds of compounds one polymer based for normal application other ceramic / metal based for high temperature.

You apply it as a paste when dried is toughf, you can machine it afterwards. The good thing is that since there is no heat involved, there is no warping of surfaces.
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Old 24th September 2010, 00:05   #163
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Originally Posted by PAVAN KADAM View Post
Hi guys,

I was totally distressed after the Head sprung a leak. And did not concentrate further on the engine. Engine head is getting a bit of attention these days, we are doing a pressure test to check the leakages, we are tapping them to close them. Maybe in next 10 days time, we will be able to get the Head repaired in perfect condition. If nothing works, we will go in for a BRAND NEW HEAD from Italy.
Hey Pawan. If I may suggest, as done before, go and buy that new head and stop wasting time. If the new head is good, the car will be perfect and run well atleast for the next 30 years.
The old head you may send/bring to Mumbai, and I will put you in touch with a workshop. I am confident, if he cannot fix it, no one can. But first get that new head.

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Originally Posted by IndrojitSircar View Post
I would not recommend cold welding for this head. My suggestion is to use hot welding and then reface the head and only if it is a compression problem. Other wise I would do the same as Mr. Behram has said and also try and get the Workshop manual if you can. It does wonders at times.
I strongly and totally disagree. Calling ALL bhpians who personally or their near and dear friends/enthusiast circle got a "fried" engine after HOT welding anything. I can point out a vintage Buick in Pune for starters. If anyone has any cracked engine part, the first option is metal stitching. It works, I can assure all, sometimes it is not feasible depending upon the location of the crack. But hot welding? Innumerable engines have been fried (not fired) because of that. If anyone has a problem, I could direct them to help.

Cheers harit

Last edited by harit : 24th September 2010 at 00:18.
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Old 24th September 2010, 00:18   #164
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Hey Pawan. If I may suggest, as done before, go and buy that new head and stop wasting time. If the new head is good, the car will be perfect and run well atleast for the next 30 years.
The old head you may send/bring to Mumbai, and I will put you in touch with a workshop. I am confident, if he cannot fix it, no one can. But first get that new head.



I strongly and totally disagree. Calloing ALL bhpiand who personally or near friends/enthusiast circle got a "fried" engine after HOT welding anything. I can point out a vintage Buick in Pune for starters. If anyone has any cracked engine part, the first option is metal stitching. It works, I can assure all, sometimes it is not feasible depending upon the location of the crack. But hot welding? Innumerable engines have been fried (not fired) because of that. If anyone has a problem, I could direct them to help.

Cheers harit

You are 100% Bang on the perfect recipe for disaster.

I agree with your view point.

I would want to tell all about my theory

1) I have increased the Head Height with Cold welding - HEIGHT PERFECT

2) I have faced it to perfect Flat surface - SURFACE FLAT PERFECT

3) The engine starts and idles fine - BUT WITHOUT WATER

4) So as per me the Head is perfect - ???

5) With radiator connected, i get droplets of water dripping from Head - ???

6) So if i plug the leaks at the lathe . - ?????


I feel i am confident of making this head work,

Harit sir, you views on this please.
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Old 24th September 2010, 04:23   #165
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I strongly and totally disagree. Calling ALL bhpians who personally or their near and dear friends/enthusiast circle got a "fried" engine after HOT welding anything. I can point out a vintage Buick in Pune for starters. If anyone has any cracked engine part, the first option is metal stitching. It works, I can assure all, sometimes it is not feasible depending upon the location of the crack. But hot welding? Innumerable engines have been fried (not fired) because of that. If anyone has a problem, I could direct them to help.

Cheers harit
Sir,

First thing i want to know is that which year and model is this VINTAGE BUICK. Does it also have an aluminium cylinder head ?

Hot welding is a pure disaster if done on a cast iron cylinder head. Since this car has an aluminium cylinder head Hot Welding works better.

Cylinder head damage has become more common as car manufacturers use mixed metals in their engines. Many vehicles, for example, have a solid cast iron engine block but an aluminium cylinder head. These two metals expand at different rates, and this can also lead to cylinder head cracking. One of the other major sources of damage on Cylinder heads is overheating.

To the best of my knowledge , Aluminium is best Hot Welded and Cast iron is best Cold welded.

Here is something i would like you to read -

Quote:
The Best Way to Weld Aluminium


Welding aluminium is unlike welding other materials, such as iron. You will need to take more time to prepare the materials if you want a clean, strong weld, and your welding technique will need to be modified as well. In some applications, you may need to pre-heat the metal prior to welding. Although it takes more prep time and a different welding style, with a little practice, you can achieve a clean and solid weld on a piece of aluminium.

Safety First
  1. When welding any type of material, wear all needed safety gear. This includes gloves, hearing protection and a heavy apron to protect your body from hot splatter. Wear eye protection to shield your eyes from thermal burns. Make certain the work area is well ventilated in order to remove the fumes generated when welding. As an added precaution, keep your face away from the fumes as much as possible.
Material Preparation
  1. Prepare the aluminium. The first step in this process is to clean away any lubricants. Next, remove the aluminium oxide from the surface of the metal with a metal brush. Brush in only one direction, and do not use a brush that has been used on other materials. It is necessary to remove the aluminium oxide due to the vast differences in melting points for the aluminium oxide and the base aluminium. While pre-heating is not generally necessary, if you are welding two pieces of different gauge aluminium, preheating can help prevent some problems. If you pre-heat the aluminium, do not exceed 230 degrees F.
Welding Technique
  1. Aluminium has a much higher thermal conductivity than other materials; higher amperage and voltage is required to achieve a solid weld. Weld at a fast pace to keep the weld smooth and even. With materials such as iron, it is normal to pull the weld toward you. When welding aluminium, always push the weld away from you. Attempt to keep the welding tip at a 10-to-15 degree angle for best results. The keys are to weld hot, weld fast and push the weld away from you. This will result in a solid weld that's clean and strong.
By Tom Raley




Quote:

The Best way to Weld Cast iron with out cracking

The problem faced when welding cast iron is the high carbon contest of the steel. This 2 to 4 percent carbon content causes the iron to be brittle and difficult to weld without cracks forming in and around the weld. Many experts recommend placing the newly welded object immediately into a warm container of sand, or if the object is too large to be submerged in sand, the area should be wrapped to prevent it from cooling down too quickly.

Instructions
  • Preheat the container of sand in an oven at 300 degrees F for several minutes. The sand should be warn, but not so hot that you can't stand to lay your hand on it. Stir the sand to make sure the heat is evenly distributed. Set the container aside within easy reach.
  • Using the steel wool, thoroughly clean and buff the area to be welded.
  • Light the propane torch and adjust the flame to a low setting, slowly pass the flame over the area to be welded to preheat it. Just warm the area slightly, getting the area too hot will cause the cast iron to crack and flake off. The area should not be so hot that you can't stand to touch it with your finger.
  • Put on the welding gloves and the helmet or goggles. Using the stinger to hold the cold weld rod, with the welder set to a low current to minimize admixture, apply a thin even layer of soldier to the area to be repaired. Make a short weld about 1 inch long to avoid overheating. Immediately submerge the welded area in the warm sand and walk away, allowing the area to cool slowly.
  • Remove the welded object from the sand when it has cooled. If additional filling needs to be done, clean and buff the area with the steel wool, reheat the container of sand as, and repeat Step 4 until the area is filled and repaired. Let the object cool slowly in the sand each time you repeat the application.
  • Buff the finished weld to remove rough areas.
By - Paul Parsons
The above two people are experts who have been welding for more than a few decades now in their respective welding fields and are masters at it.

Hope this makes things abit more clear.



Last edited by IndrojitSircar : 24th September 2010 at 04:31.
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