7MGTE BWL (BIG WATER LEAK) Where is it coming from?

[Bowlsclubboy]

Hey guys, my missus had her MA70 7MGTE bohemoth on the track on the weekend, after 2 laps the temp starts to climb so i tell her to head back to the pits.

Upon opening the bonnet we're hit with smoke which was burnt oil from the cam cover valley (due to no water whatsoever), along with coolant EVERYWHERE but in the radiator.

Tracked the leak down to somewhere around the waterpump and as much water as you put in the rad, all comes out of there. So i pull the waterpump off and clean the surfaces as best i could, then smear a heap of hard setting permatex/loctite gasket shit on both parts and slap it back togther, fill it full of water and same problem again, the trickle of water seems to come from just behind where the waterpump bolts on, any ideas what i will need to be replacing here? Is there a big rubber gasket on this plate that seems to encapsulate the front main seal also?

If i have to replace some major seal how many dollars are we up for roughly if anyone knows?

Thanks in advance to anyone who replies.

Cheers,

Troy

[Shifty]

Troy

Can't help with your specific problem, but to be honest the 7MGTE isn't the best motor when it comes to cooling issues. I'd probably start eating cheaply and putting money away for a fresh rebuild or an engine conversion.

[RONA]

Agree once said leak is sorted get a comp and or Teekay test done immediately. Over heating a 7m to the point that its burning oil is bound to be a time bomb.

[Soarer_D00D]

Get a 1J.

Simple.

[whatthe?]

There's a small 90 degree rubber hose under the thermostat housing (the big rear part of it where it joins the block). I'm betting the hose has perished. It's a common enough thing after 20 odd years. It's close enough to the water pump that it may be giving you the impression thats where its coming from

Other tha that there's a weep hole in the pump itself, but it isnt big enough for water to 'piss' out of, no matter how rooted the pump is

And can we keep the 'get a 1J' comments to the non-tech areas? I dont recall him asking for advice on what to replace the engine with

[Bowlsclubboy]

Thanks for the replies guys...and yes, she wants a 1j and an r154 lol.

Ive ordered a water pump gasket for a start until i delve deeper.

Seeing as i cain the piss outta my 1jz cressy on the track and it never skips a beat i can see why everyone is suggesting it lol.

Cheers,

Troy

[Mundoolun]

I have had simiular issues with my 7mgte. I replaced the radiator and water pump thermostat and radiator cap and all old hoses and one broken water temperature sensor and headgasket and it still overheats out of overflow bottle. I would look up importbitz.com in Brisbane as they often have MX83 Cressida 1JZGTE manual cuts and actually have several full manaul r154 kits. Worth a look. The 7mgte is a long stroke motor only good to rev 5500rpm wheter the 1JZGTE is a short stroke 7500rpm has a yamaha head and metal haedgasket as stanard and a reputation of being bullet proof. At least replace water pump, belts,timing belt, plugs and thermostat and have injectors overhauled and new gearbox fluid when putting in motor. The first step is 3"inch exhaust including a new dump 4"metal cat and large rear muffler, Next whack a kn or similar panel filter and large front mount intercooler and piping and fitt atleast a haltech piggback computer. Install a larger fuel pump and adjustable fuel regualator and have stanard turbos highfolwed by buying two good condition CT9 Satarlet turbos and new bearings backcutting stanard housing and steel wheels now is place run 15psi allday long if clutch is still not slipping and easy 240rwks-260rwks for the taking.

[EldarO]

I have had simiular issues with my 7mgte. I replaced the radiator and water pump thermostat and radiator cap and all old hoses and one broken water temperature sensor and headgasket and it still overheats out of overflow bottle. I would look up importbitz.com in Brisbane as they often have MX83 Cressida 1JZGTE manual cuts and actually have several full manaul r154 kits. Worth a look. The 7mgte is a long stroke motor only good to rev 5500rpm wheter the 1JZGTE is a short stroke 7500rpm has a yamaha head and metal haedgasket as stanard and a reputation of being bullet proof. At least replace water pump, belts,timing belt, plugs and thermostat and have injectors overhauled and new gearbox fluid when putting in motor. The first step is 3"inch exhaust including a new dump 4"metal cat and large rear muffler, Next whack a kn or similar panel filter and large front mount intercooler and piping and fitt atleast a haltech piggback computer. Install a larger fuel pump and adjustable fuel regualator and have stanard turbos highfolwed by buying two good condition CT9 Satarlet turbos and new bearings backcutting stanard housing and steel wheels now is place run 15psi allday long if clutch is still not slipping and easy 240rwks-260rwks for the taking.

7M's use yamaha heads too, in fact, i think all toyota engines do...? (dont quote me)

the MX83 never came manual, let alone 1J, what your referring to is a JZX81 chaser, which are getting a bit rare now.

however its completely irrelevant to the question, as you'd have a headache of a time putting a JZX81 1J into an MA70 (what his girlfriend has) as one of the main differences is that the chaser uses a front sump, whereas the supra uses a rear.

the fact that the 7M is a long stroke motor and the 1J is a short stroke motor has no relevance either, as the 7M has more displacement which makes it a bit more powerful off boost, whereas the 1J needs more boost, and higher revs to achieve the same deal.

ive said it before, and ill say it again.

the 1J is a quick answer to your problem, for the money you spend on the 1J, you can pull the 7M, machine and restore it back to stock, fix it up, and have a motor thats more reliable than the 1J (which you dont know the history of, its always a gamble).

fix the 7M only if you have the time and patience to do so, reco'ing the head, making sure the block is flat, a metal head gasket and a set of ARP studs will see you having a reliable 7M, not to mention a practically new one, and while you have it out, plugs, water pump etc. etc.

to me it sounds like your girlfriends motor is too far gone and needs to be replaced or repaired, either way, it needs to come out to be fixed properly, its up to you and her as to what the best thing to do is.

Eldar.O.

[Bowlsclubboy]

Dont you hate it when someone tells you the awful truth? lol

Tracked the leak down to that small 90deg hose beneath the thermostat housing, the pipe felt like a piece of sponge and has a huge tear/bulge in it. Its a prick to get to but those spring hose clamps make it twice as hard.

Off topic but im fairly certain that no 1jz powered x80 series car came with a manual. It seems stupid i know but thats what toyota did. I can get a manual jza70 halfcut from cvap which is only an hour away if i wanted to anyway

I dont know if anyone else notices how thirsty their 7mgtes are but her car has always sucked the juice even though its driven very sedately. The reliability ive had with my 1jz and the fuel economy would be the main reasons id do the swap. The cons are insurance/engineering and the fact that i know eldar probably speaks from experience lol.

Thanks guys, Troy

[whatthe?]

Much easier with the rear thermostat housing off, it isnt that big a job.

I love being right

[MTD]

I love being right

Don't you just matty!

[whatthe?]

Who's this? Not one of those Honda loving Chatswood boys is it?

Hrm, by that signature I'm now thinking Mrs Dong?

[MTD]

Thank you for the poor stereotype matty.

What's wrong with hondas?

[whatthe?]

MTD = Mrs Teh Dong?

[MTD]

Now what made you think of that?