mikuni

Sheepers' RA28 Celica

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24 minutes ago, kyteler said:

Running slightly lean due to extra air and overheating? 

My first thoughts and came to say that here ^,

Is there a bunch of drag from the supercharger, they take a bit of power to drive

Can you remove the belt and run it with no S/Ch?

 

 

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Its not something stupid like the water pump being spun backwards?

From memory a UZ has the pump running off the back side of the serpentine belt and when you added on the S-Ch you didn't make the pump run the wrong way by rerouting the belt?

 

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Actually forget that, water pump is driven from the cambelt.

Also you have a fresh motor so that shit be tighter than a goldfishes asshole, so overheating is not unexpected during break in period.

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If it's just during break in, is it something that water wetter and some pricey coolant could remedy in the interim or is that a preposterous theory? 

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I would try some things just for testing

1. Set a higher idle target so the waterpump is spinning faster. Make it a little on the rich side and pull ign timing a bit

2. Set a lower idle target so you can see if less supercharger work/heat makes a difference.

3. Find someone with a thermal camera and do some nerding

4. Post some graphs

Also, how'd you go about sorting an E-throttle signal for the pedal? Did you retrofit something to the standard pedal?

Also, I find widebands to not be particularly accurate at idle conditions so looking at the tailpipe is a good sanity check. 
Any possibility of a stuck injector or something like that? 

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Hello Sheepers.

Is the cooling system circulating as it should? the top and bottom hoses are both hot when the engine is overheating?

I'd be tempted to get the tanks off the radiator and see what the core is like. It might have been blocking previously but not caused a problem, now the extra load has tipped it over the edge.

Whats the radiator cap like?

My two cents.

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Friend had this happen to a fresh built SR he had. Turned out the exhaust cam was off by a tooth so cyl press was building for to long until the valves opened.

might not be the issue having two banks but is easy to check

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firstly thanks for your input everyone. deff some things to think about/try.

i tried knocking the idle back as far as i could and it made no difference. its already rich and retarded a bit for the running in period. im loath to put more fuel into it, its already borderline bore washing as it is. 

 

the radiator and both hoses deff get hot so there is flow for sure. when it first gets to 88 degrees (from cold) the fan will pull 2 degrees out of it and switch off but you can see the inlet temps rising slowly and the next time the fan kicks in it cant keep up so there is deff flow through the radiator and the fan is doing something, just not doing enough.

the radiator cap seems fine, its not weeping or anything.

 

more questions for you to ponder and give me your thoughts on,

the head gaskets are stock toyota, do you think the cooling ports in the gaskets should be larger to allow more flow or do you think that toyota knew what they were doing and fucking with the hole size would just make more problems?

 

i will try and run it tomorrow with the supercharger running and see what happens

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Worth getting the radiator cleaned out first to confirm its not partially blocked before you go pulling cylinder heads off?

 

 

/ convert it to meth

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Few Stupid thoughts, is the fan setup exactly the same as previously? Haven't rewired or setup via the ecu for it to blow the wrong way? Is it a genuine Thermostat? Could it be sticking partly open? 

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the fan is deff running the same as it was before as none of the wiring for that has changed, only the triggering for the relay has changed. 

thermostat in non genuine but ive run the motor with and without a thermostat  and it made no difference.

seems to be a bit of pressure in the radiator hoses as well.

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I just googled the head gaskets they are close to symmetrical but not quite, it looks like some water holes might be blocked if they were put on back to front.

I'd check the radiator, get the tanks off etc. It's cheap insurance for a new motor anyway.

Replace the thermostat with a genuine one.

If that didn't help, have a good hard look at the water pump.

Sounds like the fan is working as it should.

Beyond that you might have to look inside the motor. Does it have oil squirters to cool the pistons? I've heard of people leaving/misaligning them and it causing heating problems.

Sorry if that's a lesson in sucking eggs, good luck.

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just checked the photos and the head gaskets are definitely on the right way round.

water pump is genuine toyota, i would hope its made correctly. 

still scratching my head on this one....

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Head gasket isn't symmetrical? 

Oil drains? Wouldn't line up very well, and the water passage on the right here would be poking out the other end?

SCA_SPO6652304_hi-res.jpg.e14b6bced8339da267b3698043b40aa0.jpg48840357723_1d86f7f388_c.jpg.d0f83600512a310950c540217e101763.jpg

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