engine block

I don't see any diagrams.

For such aluminium blocks, unevenness can be machined but there is a limit to how much can be machined. If the outer edges of the cylinder liners have eroded, replacing the block is the only option as there would be insufficient support for the gasket and repair would not last.

Well thank you for the quick response.
The problem i am still having is that my radiator drains out when I turn my a/c on and reached at 70km/h speed, i know that the block is not in a good shape besides that when i open the heated car bonnet the radiator is sucking water from the bottle and driping it at the same time from the bottle cap meanwhile the radiator has generated enough gas pressure. secondly when I start pouring water into the radiator when the pressure is minimized it shows no oil mixing as i discussed earlier that my block seems to be weak but there are few air bubbles NO oil & water mixing all i can see is clean water remainings and no rusty water. I have serviced the radiator 2 times but that was almost one year back. please guide me what to do.

The head gasket design does not easily allow coolant to get the oil or vice versa so it is not surprising if oil or coolant are not contaminated.

If you have not replaced the radiator cap, get a new one to test. Remember to bleed the system before installing the radiator cap.

If pressurised air is being discharged into the cooling system, either the system has not been bleed correctly or you have leakages from the gaskets.

well i again appreciate your reply once again. in january 2010 I installed a new gasket (steel one) (glide) and my mechanic removed the rubber under the radiator cap (may be so that pressure can be released) it worked perfectly fine till last month i.e. november 2010 but suddenly by a/c compressor was not cooling well so i went for a gas refill and he also changed a rubber pipe for the a/c. then the a/c started working fine but the problem arised into the radiator (the story i hv mentioned earlier). well tonight i am going to bleed my radiator and then will see what would happen by the way what i understand of the term 'bleeding the radiator' is to empty the radiator by removing the nozzel at the bottom of it and refilling it without putting the nozzel back and when the water starts coming out at the nozzel opening with as it is being put into the radiator. i hope it really does not mean by dismentaling the radiator and get it serviced with a professional person. awaiting for your comments. iam trying to attacg the engine block pic once again (it was taken in january 2010)

The areas I have circled are likely to leak pressure from the cylinders. Under such circu,stances, oil woul d noty get to tyhe coolant and neither would coolant get to the oil.

Removing the rubber from the radiator cap is going to reduce the pressure from the engine and this would lower the boiling point of the coolant. Coolant would be pushed out to the recovery tank resulting in the level rising and dropping by a large margin.

The person who did this either knows the engine has a problem which was not rectified or he knows nothing about the cooling system.

Bleeding the sysytem means to top up the coolant. Run engine without radiator cap and top coolant as level drops to bleed the system of air. Do not start engine for more than 5 minutes as coolant can expand and shoot out of radiator neck.

After coolant level stabilises, close radiator cap and run engine till fan comes on. Stop engine and allow to cool before checking coolant level again. Top up if necessary.

Replace the radiator cap. It is bad and no matter how many times you bleed the system it is not going to work.

so ur telling me to bleed the system as you described in ur message, secondly to get a new radiator cap with a rubber installed under its cap? does my block needs replacement or i can continue with it by servicing or bleeding the system. i will today try to bleed the system again as i didnt know the meaning of the term 'bleeding' and shall post you again meanwhile please guide me for what i hv requested above.

If replacing the radiator cap stops the coolant losses and overheating, then you can continue to use the block.

Otherwise the block needs to be replaced if you wish to resolve the problem.

Dear KHLow, first of all i really appreciate all your suggestions and replies.
now the thing is that for bleeding the system as i am not a techy, u mean to say to first remove the radiator cap, start the engine (cold or hot?), pump up the accelerator or not to?, topup the (coolant or water?) as i am using water and when the level of coolant or water drops i add more water and top it up again and i may keep on doing this until 5minutes (in my case the cooling fan is direct).
in any case for bleeding the system i donot need to remove the nozzel which is located at the bottom of the radiator to empty the radiator.

please guide me in this process step by step

shall appreciate your reply

Start with cold engine.
Start and let it idle.

Others are as you mentioned.

DO NOT remove the drain plug. You are going to bleed the system and not replacing coolant.

You have the cooling fans running on all the time, I guess you have removed the thermostat as well. In this case bleeding is simple.

Start engine, top up coolant until it stabilises and close radiator cap. That is all you need to do.

thanks will do it tonight, and for the thermostat its working fine and the temperature niddle in the temp guage remains almost at the half point during the normal run and when i drive the at the speed of 70km/hr plus with the a/c on the abnormal functions starts as mentioned earlier and the temp. niddle starts rising above the half point and as u have mentioned abt the thermostat i would also like to bring one more thing in ur knowledge that when the warter starts dripping from the radiator plastic bottle the niddle of temp. keeps on the half point but has shifted boiling water to the bottler from the radiator. thanks for the tips, will inform you abt the progress when done. thanks again

oh yes the thermostat valve is also removed from my car do i need to reinstall it or run the engine with its presence. what effects would it cause if removed, the normal outdoor temp where i live during winter is 25C to 15c and durinf summer it is 45c to 30C

i did the procedure using coolant and replaced the radiator cap with a new one.
then i went for a test run, turned on the a/c and again went at the speed of approx 80km/hr. this time the coolant didnt went into the bottle but the temp rised almost to full during the test run and when i opened up the radiator cap to refill there was too much pressure built up and approx. one liter of coolant was ejected with a high pressure. i dont know what to do next!

With thermostat valve removed, it is equivalent to having no thermostat. When an engine does not have a thermostat, the temperature should not be showing at middle with radiator fan running all the time. It should be much lower than that as the engine should be running cooler than expected. Either there is insufficient coolant in system or the cooling efficiency is below par.

Repeat the bleeding and go for a run. DO NOT open the radiator cap until coolant is cold. When engine is cold, remove the radiator cap and note coolant level.

I need to know if coolant is depleting from system. When engine is hot it would have high pressure and when the radiator cap is opened, it would definitely gush out. This would not allow us to understand if coolant is depleting.

If overheating only occurs when you are running at high speed, the problem could be clogging in the cooling system or insufficient coolant. Check the radiator for clogging. Check the coolant passages/hoses for clogging/kinking.

hi there... sorry i was away for a few days (out of town), well today i have got my radiator serviced, it was chocked but yet i have not taken a test drive will do it tonight and will post u.

Hope it solves the problem.

it really effect the performance but yet i hv not taken a dreadful test drive cuz now the problem is that "when the radiator was dismentaled (taken out from the engine compartment) at the bottom of the radiator there was a leak about 1.5inches long and was prompt cuz of use of green clored coolant. now the radiator was further dismentaled and was found 70 to 80% chocked... after the radiator was serviced it was getting difficult to put the radiator 'plastic bottom' back to the radiator body by the technician and a rubber packing was also found in the radiator whcih had been streched out due to any reason, so the technician put in another rubber (not new) and then finally closed the groves of the radiator by attaching it to the plastic bottom with the help of a pair of plairs. this was done after 3 tries. every time the radiator was not getting into the plastic bottom as a perfect fit. so that was abt the radiator, this morning when i checked the bottom of the radiator i found a drop of water dripping again probably from the same place, i went back to the radiator service man and he told me that it will get alright itself when the engine will get enough hot during a reasonable run. the total amount of water that was dripped over night was about 100 to 150ml approx. may be less............... now advise me either i get the bottom replaced with a new one which shall be of brass or put silicon or any other material (please do advise if any material can be used, one of my friend advised me to use DOW CORNING 732 multipurpose RTV sealant around the neck of the bottom or let it be as it is for the time being and wait for the time so that the leak may vanish itself.... awaiting for ur quick response

The radiator would be under pressure when operating due to increase in temperature and if there are any leaks, it is only going to get worse and not better.

You need to get the bottom tank seal ring replaced and if the core is bad, the radiator would have to be replaced.

Any sealant is only going to be temporary as the presure would sooner or later force itself out. Radiator joints are sealed without any selants. The rubber ring has to be compressed to make it withstand certain pressure.

Either you get someone who can do a better job of repairing the radiator or else it would have to be replaced.

first of all marry xmas.
ther were no leakages since last night and will still monitor it for a couple of days and if there would be no leakages (physical) then i will go along with the radiator presently installed.

besides this i am also planning for a complete car make over i.e. body repaint cuz it is effected with rust, the other important work which needs urgent attention is the replacement of tie rod end and steering rod bush kit as i feel light****** in my steering

Thank you your solution has worked for me so far

Glad to know of this.

Have a nice day.

Hi KHLow

The radiator has again started giving problems, i guess i need to replace it with the new one.

As you can see in the fig. above and as i hv discussed it also with you... kindly advise what if i only change the block (which is made of silver) of the engine and leave the head as it is. (japanese used block is available in the local market here)

what are the pors and cons of this situation.

your advise as always matters a lot.

I don't think it is a problem with the radiator.

You can reuse the head if it is good. Get it checked for warpage and if it is within sppecs, there is no reason why you can't reuse it since you are able to get used short blocks.

The block is made of aluminium alloy, not silver.

didn't understand a word about the block... were u able to see the pic of the block? i have checked it with many vendors in the local market and they are of the same opinion that the block is made of silver.
what is warpage?
when i get the radiator serviced the water in it was circulating in a circular motion which was visible when i open up the cap of the radiator while the engine is running but now it is not running in a circular motion but giving bubbles.

if u were able to see the block then i was talking about the highlighted area by you in red (which is made of silver)

No engine blocks are made of silver.

Bubbles indicates there is compression leak from the cylinders via the head gasket and mostly are due to bad cylinder block surfaces as I mentioned in earlier replies.

Warpage means the head is not level due to overheating. If the head is still withins specifications, it can be skimmed (refaced)

So what do you suggest should i install a new radiator first (which is now almost 10 years old) or get the block refaced or changed (i dont think so there is any room for refacing as you can see in the pic above). Changing only the block but not the head will cause any effect on the engine performance? or if i change the block then i must also change the head as well? (Only used blocks are available)

or may be the sleeves are made of silver not the complete block ofcourse.

For more details about the car / engine details i would appreciate i you can visit the following site

http://en.wikipedia.org/wiki/Honda_City

my car is third generation type.

If the head is good, changing the block would get everything back to specs. When you buy the blovk, ensure the surface is flat and shiny smooth. Avoid blocks that have the outer edges of the cylinder liners that are rounded. A good block will have sharp edges.

Changing the radiator is not going to solve the overheating problem. The block should be your prirority now.

We do have this model over here in Malaysia but not the complete data.

I have never heard of silver being used in engines.