My 76 1UZ build

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This little gem is singularly the biggest pain in the butt on this whole build. I have had the housing off an on so many times i've lost count and it still leaks. First it was the thermostat seal that was just a little too thin to seal and now its the seal between the thermostat and the block, replaced with OEM. Then the housing to block seal has been leaking - I've tried the oem gasket, a home made cork gasket, 2x with gasket maker, I've lapped flat the housing, smoothed the block surface, ensured everything was dry during mating the surfaces, ugh. Last night I got it to a very slow drip and then cranked the bolts - maybe this round with the gasket sealer will work.

The block side of the joint seems to have a trough in it, really looks like there should be an OEM rubber seal there, but none of the 1UZ forums seem to reference one, nor does the various parts diagrams, doesn't help that its a JDM engine, but that part should be fairly consistent across the platform.

(ignore the vacuum seal plug, it will get replaced, but its the only part of the bloddy thing that didn't leak)

Anyway, least I am finally doing some :poop:
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Oem just used sealer . clean the grove out on the housing side . there are aftermarket paper gaskets but i always just used sealer , same process as the 2uz . Is the water pump stock or aftermarket , i have seen a few aftermarket ones that the ( block ) aka top of the waterpump was cast wrong , either to short or bolts did not line up
 
Those pictures look very familiar :)
Mine does seem to be well mated, the thermostat side was lapped dead flat, the housing side seemed fine, if I have to pull it again I will do a more thorough check. I cant recall if my pump was aftermarket or OEM - I am hoping it holds so I can move back to tucking my exhaust up.
 
Thanks @scrapdaddy, I've never used this stuff before, sounds like it will do the trick. Ordered from Amazon, their site seemed to have a problem with Canadian addressed and shipping calculations. Bit by bit I am picking away at the project - moved the pig te other day unser its own power, so that was a thing :)
 
Those thermostat housings are kinda crap. Brad Oliver - Venom Automotive - https://www.venomautomotive.com.au/ - makes a billet version of the plastic part because they ALL warp, and if you pull the hose forward, the housing will leak. happens on ALL of them.

The harness you got, is it for factory ECU? Because I have megasquirt on mine and have tons of tunes and stuff because ive been buildin performance stuff the UZs for almost 13 years now lol


Also - for the rectangle port from water pump, just FIPG, but you gotta let it set a little. The oring from the crossover pipe behind the water pump is the only thing I worry about. Then i use a little FIPG on the large oring for the housing that pops into the front water bridge. Of all the engines ive redone the timing on, ive only messed up the oring behind once, and boyyyy does it leak when its damaged. CLEAN and let the FIPG set a little. I typically put the goop on, then clean the surfaces, slap it together and fill it right away I dont wait the curing period (shh thats a secret). Most people mess up the bank 2 timing more than anything because when you pull the pin on the tensioner it jumps a tooth if youre not holding it
 
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Those thermostat housings are kinda crap. Brad Oliver - Venom Automotive - https://www.venomautomotive.com.au/ - makes a billet version of the plastic part because they ALL warp, and if you pull the hose forward, the housing will leak. happens on ALL of them.

The harness you got, is it for factory ECU? Because I have megasquirt on mine and have tons of tunes and stuff because ive been buildin performance stuff the UZs for almost 13 years now lol


Also - for the rectangle port from water pump, just FIPG, but you gotta let it set a little. The oring from the crossover pipe behind the water pump is the only thing I worry about. Then i use a little FIPG on the large oring for the housing that pops into the front water bridge. Of all the engines ive redone the timing on, ive only messed up the oring behind once, and boyyyy does it leak when its damaged. CLEAN and let the FIPG set a little. I typically put the goop on, then clean the surfaces, slap it together and fill it right away I dont wait the curing period (shh thats a secret). Most people mess up the bank 2 timing more than anything because when you pull the pin on the tensioner it jumps a tooth if youre not holding it
Dropping some UZ knowledge!!!
 
Thanks @BoomerUZ, appreciate the feedback, also reassuring to know that it wasn't just me on the thermostat housing. I did finally get that to settle in on the 6th try, I should have thought of FIPG.

The ECU is the Link Monsoon, harness was built by Kelvin Glover (Cartunes) in NZ. I had originally tried to fix up the OEM, but i was too far gone - after a lot of back and forth with Kelvin, we decided to give up on my original and just go with the Link. It has a basic tune on it now, once up and running I will get it on a dyno and tighten things up. I have also done the air intake mods and just have the Lambda sensor left to install.

Hoping to get some time later this month to advance a bit on the truck, redoing a bit of the tunnel and building a better mount for all the shifters is the next thing, we'll see - tim eis contingent on clearing a boat project and getting going on residing the house
 
@RUSH55 no, mig. would like to buy one, but the boat has been creating a large sucking sound in my wallet. I know a guy who likely knows a guy though.

A buddy of mine from Calgary uses his tig to go over his mig welds to pretty them up, something some of my upside down welds could use :)
 
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There was talk on @scrapdaddy ‘s thread about welding some v-clamp faces onto the headers and pipes and doing away with the flanges with gaskets.
Vibrant Performance and Stainless Brothers make some better clamps, then there’s the eBay fare for cheap. Something to think about anyways. I’m gearing up to do mine since the exhaust hasn’t been started yet.


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