Hi guys,

 

My waterpump has failed couple of times lately, used second hand pump,

 

But it keeps failing since i put a chipped ecu on it (central 20) and im starting to think it could be something to do with the raised rpm limit, Held it in 2nd once and it went to nearly 90mph and not sure exactly has it was a while back but somewhere between 8 and 9,000 rpm,

 

Obviously i aint holding it that far anymore but if your in 1st or sometimes 2nd and you power it up and it spins up, i have noticed before i have had time to let off the revs have raised pretty high, cant really watch revs to see how high more worried about if im still going straight or round in circles lol.

 

Got another pump coming (new) lol,

 

And what I really wanted to know is i have both uk and jap spec pulleys for pump, what one slows the pump down im thinking the bigger one but i may be wrong anyone else Know for sure,

 

Also is it the uk or jap spec car that has the one that makes it go slower, cause have ordered jap spec belt from z centre and i know its gonna be the other i want its allways my luck,

 

my car is made from a jap spec and a uk car, I restored it with the jap spec shell and do you think i can remember what bits i used to build it up - hell no ???.

 

Any help appreciate thank you.

Edited October 17, 201114 yr by Terry

All I can really tell you mate is that the UK pulley is bigger than the JDM.

All I can really tell you mate is that the UK pulley is bigger than the JDM.

 

Cheers mate so tomorrow gotta work out if i have the big one or the small one on it,

 

And gotta hope if i do need the bigger pulley to slow it down the jap spec belt will fit,

what is failing? the impellor, the bearings or the seals?

Do you have a lightwieght underdrive pulley? I THINK they are much smaller than stock so alter the water pump speed.

the waterpump is the last of your worries if your taking it above 8k rpm

see i was thinking about this thread today and back to mikeys one about rpm. now these chips that allow you to rev that high without a rev limit is taht good, i dont think it is. peek torque and bhp would be reached at what 5.5k to 6k revs. so going into the 8s is not only dangerous to the internals of the engine its fairly pointless???

If I understand this correctly,:whistling:

The bigger the pulley on the water pump the slower it will run.

My logic being, the fixed rpm is governed by the crank pulley and will deliver a relative length of belt per revolution, so the greater the circumference of the pump pulley the slower it will revolve.

Think of it like a 6 speed gear system on a push bike, but in reverse.

I think I need a lie down.:closedeyes:

If the pump is failing id guess at an over-tensioned belt or a dodgy viscous coupling.

Sorry guys thanks for your replys, thought it was the bearing in the pump that had failed again, and jammed the pump snapped the belt so took my new pump and belt to fit them,

turned old waterpump the other night was making grinding noise and jamming but was dark, today it was fine - exept the 8mm socket i had lost was behind it lol, well atleast it was an easy fix new belt done lol,

 

Try not go anywhere near 8000rpm anymore but has their aint no rev limit at all, if i am giving it a bit of stick and rear wheels loose traction by the time you have realised and let off the revs have raised quite high, was just worried it could be that making pumps fail, revs proberly aint even going that high but its stupid has theirs nothing to stop it so your constantly watching to make sure you dont hold it to long.

 

Thanks again everyone.

there should be a rev limiter in built in the car most chips will raise that.

there should be a rev limiter in built in the car most chips will raise that.

 

Thats the problem with my central 20 ecu they have completly removed it the fu@kers,

 

it will just rev and rev till it goes bang lol,

 

Has you say they normally raise it not remove it completely,

 

cheers 4 replys mate.

could alwsy instal an aftermarket revlimiter or fit a different chip.