4efte overheating when boosting only

[Fahim]

need urgent help please.
I have changed my radiator,radiator fan,head gasket,head bolts,removed thermostat,but car is still overheating under boost only...car doesnt overheat all day if i drive normally.
When i bought the engine,i rebuilt it using new piston rings,new valve seal,new headgasket.
One of my piston was bit cracked so i changed all my pistons using 5efe pistons
I polished top of the 5efe piston and installed them,the piston looks same as 4efte piston now.
Compression is good enough,getting 10bar-12bar in all of the cyclinder.
Now need help for the overheating issue.

 

[Fahim]

Anyone?

 

[Calum122]

Properly bad for engines to run without a thermostat.

It helps pressurise the cylinder head. This in turn stops stale pockets of coolant vaporising under the heat of the engine and cause localised boiling of the cylinder head. Which in turn will warp the aluminium.

Removing the thermostat is never the answer, it masks underlying problems with the engine.

 

[Fahim]

Properly bad for engines to run without a thermostat.

It helps pressurise the cylinder head. This in turn stops stale pockets of coolant vaporising under the heat of the engine and cause localised boiling of the cylinder head. Which in turn will warp the aluminium.

Removing the thermostat is never the answer, it masks underlying problems with the engine.

Brother i didnt remove the thermostat,infact i didnt geat a thermostat with my engine,when i bought it.
And from the 1st of purchase this engine was overheating.
What should i do to stop overheating

 

[Fahim]

Anyone there for help?

 

[Calum122]

Yeah that wasn't the point I was making. The point I am making is that not running one masks underlying issues. And for the cost of them go out and buy one anyway.

You may find that it becomes impossible to seal the thermostat housing which will be a big indication of added pressure to the cooling system.

 

[Fahim]

Yeah that wasn't the point I was making. The point I am making is that not running one masks underlying issues. And for the cost of them go out and buy one anyway.

You may find that it becomes impossible to seal the thermostat housing which will be a big indication of added pressure to the cooling system.

So what should i do now brother?
I need solution
Say me directly

 

[Calum122]

Well if you put the thermostat in it's probably going to exacerbate the situation.

And by that I mean you are going to find it's going to overheat even when off boost, in which case you know there is a bigger issue than simply overheating on boost.

Because if this was the case, worst case scenario you could drive the car off boost to see you by.

I assume you have had the head pressure tested when it was off.

As Duncan said, the reasons why the engine is overheating has been outlined above.

 

[Fahim]

Well if you put the thermostat in it's probably going to exacerbate the situation.

And by that I mean you are going to find it's going to overheat even when off boost, in which case you know there is a bigger issue than simply overheating on boost.

Because if this was the case, worst case scenario you could drive the car off boost to see you by.

I assume you have had the head pressure tested when it was off.

As Duncan said, the reasons why the engine is overheating has been outlined above.

Brother as i said i have changed head gasket 4times,i have faced the head a little(straighten the head from lathe)
No crack or wrap in block is found as said by the workshop.
They said they have tighten the new headbolts correctly.
I have installed double size brand new radiator,and readiator cap,installed new fan.
All hoses r checked and turbo water line is checked,workshop said the waterpump's circulation is really good.
And there is no thermostat,but car is still overheating.
Need solution now.

 

[dac69er]

just looking at the head or block may not always be good enough to see a tiny crack. as your issue is only under boost/higher rpm then it is likely to be a small crack that only a leak down/pressure test will show.
if you can get another head, that would be the most likely item to crack as the blocks are pretty strong. any 4e/5e head should do. just be aware of the difference in waterways at the inlet manifold end.

 

[Calum122]

Yeah I know, I've read you several times now.

As said, for the millionth time. Running without the Thermostat IS NOT GOOD FOR THE ENGINE AND CAN INFACT CAUSE HEATING ISSUES.

Whilst I don't think this is the case, the above statement would be appreciated if you at least acknoledged it.

 

[Fahim]

just looking at the head or block may not always be good enough to see a tiny crack. as your issue is only under boost/higher rpm then it is likely to be a small crack that only a leak down/pressure test will show.
if you can get another head, that would be the most likely item to crack as the blocks are pretty strong. any 4e/5e head should do. just be aware of the difference in waterways at the inlet manifold end.

Which head will be more appropriate for 4efte?
4e or 5e?

 

[Fahim]

Yeah I know, I've read you several times now.

As said, for the millionth time. Running without the Thermostat IS NOT GOOD FOR THE ENGINE AND CAN INFACT CAUSE HEATING ISSUES.

Whilst I don't think this is the case, the above statement would be appreciated if you at least acknoledged it.

Installed thermostat,same issue remains,car overheats under boost or high rpm

 

[dac69er]

Which head will be more appropriate for 4efte?
4e or 5e?

the head itself is pretty much the same other than a few small differences (check the waterway inlet manifold side). its the cams that would be different across the engine types.

 

[Calum122]

Nice, well leave the thermostat in place as it can mask future issues.

I found that with the thermostat in place that I simply could not get it to stop leaking coolant, which it wasn't before.

It turned out the head gasket had blown and the previous owner removed it to sell the car on to me. So it just winds me up when I see stuff botched like this.