Outer Limits 4x4 Board

G'day,
About 20,000km's ago i found out my 80 had bubbles coming out through the radiator. As i was going on a big trip and didn't have any money to fix the problem i put some stop leak in to block what ever was causing the leak. Now on the way home from another big trip it started using water again...
My motor is sprintex supercharged has a big exhaust and have fitted a pyro. It has only done 170,000km's too.

The oil isn't milky but sometimes when it started it sounded like one of the glow plugs were dead which could be caused by water leaking in to a cylinder? Is it more likely to be just a head gasket or could the head be cracked? I don't have to much money and if i'm going to fix it i want it done so i never have to open the motor again so i was wondering if i could fit a 1-hdt head to the motor as it would handle boost better?

Also on a side note the motor seems to be using a fair bit of oil? I'm thinking blowby but what would be causing this???

Cheers for any help because i'm a bit worried about how all of this is going to cost.

As far as the oil usage goes i suspect that it is possible the sprintex is sucking it through from the top cover breather. My after market turbo on my 1HZ was doing this and I purchased a good quality oil catch can and problem solved.

The water sounds like the extra pressure from the boost is seeping past the head gasket into the cooling system. I had this happen on a hilux before and on a long trip it would put pressure into the cooling system which pumped out the water into the expansion tank. I wouldnt mind betting you expansion tank is always full on trips. I solved it by having the head torqued down again and they added a few extra pounds. It solved it and it sealed but I was lucky not to have to replace the head gasket.

Bubbles in radiator only mean one thing-head gasket or cracked head. Very common on 1hz engine. They also have a habbit of cracking pistons when turbo or supercharged due to extra heat in combustion area. You cant re-torgue a 1hz engine as the head bolts are torque to yield. ie: 51ft-lb +90degrees +90 degrees. 1hdt head wont work as the pistons are different due to direct injection on 1hdt.

Are the pistons interchangeable too? Its starting to sound like a really big job already... If i pull the head off am i going to be able to see a crack in the head or will it be too fine to notice?

best left to the pros however it is possible to see a crack with the naked eye and tracking on a gasket however its probably easy for me doing it alot (every time a 2.8 patrol "gets hot all the time" or "overfills the expansion tank"

Best off finding a complete 1hdt as fuel pump and injectors are different too. Or just book it in to get the head done and see how it goes. You could remove it yourself to save some money but the rest is a pro job.

Hmmm... I don't suppose anyone has rough prices on 1hdt engines? Or 1hz heads? It all sounds extremely expensive knowing what toyota parts are like.

prices very depending where you go only advice is shop round, removal of the head isnt too difficult at all , im a mechanic but after removal im afraid i leave the rest to the head specialists thay are the pros with them.the head of wich you speak is cast iron its rare that you crack a cast iron head unless its been serverly overheated more than likely check the head out and a new gasket and it will be right , dont forget new head bolts as torque to yeild bolts should not be reused (but im sure thay have been before)

1HZ head complete are around $2500. Sorry IN24BZ but you're mistaken on this one. Cast iron head on a petrol dont crack too often but nearly every 1HZ head i have done has been cracked(and thats a lot!). !hz engine has been lightened from the factory too make them spin up easier, on the down side they are somewhat fragile. Especially in the head piston area.

HEAD GACKY!!

compression is leaking into the water jacket from head gasket....the 5 cylinder starting is probably water leaking back the other way..until it gets out the cylinder, it wont fire....when it gets worse, you will not be able to start the motor...it will hydraulic.
Best thing to fo is take the cap off the rad, and cut the rubber off it...put it back on...now all air will escape out into bottle without leaving pressure in there to pump water backwards.....try the chemiweld again

Spend the coin, get it fixed properly before you cook it and bake the rings as well. It wont be reliable to just stick some crap in the radiator. Thats more of a get you home trick.

fair enough kane , im a nissan tech you dont ever have to pull our TD42s apart hehehe well unless they are abused harshly , i got a 1hz and i have not had mine apart yet so i wouldnt really know what thay look like inside.. 400,000 kms of trouble free operation so far , its been pretty warm two or three times in its life... im sure to have jynxed it now. but in the same thing mines naturally asmatic not forced im sure this would have a fair bit to do with the issues encountered

there's a mob on ebay that sell reco long 1hz's for 3500 exchange. it's a cheap fix if you can do all the work yourself, which isn't a lot anyway.

Im a nissan man myself just haha! Ive spent a lot of time fixing toyotas tho. They keep me in a job! You're right naturally aspirated a 1hz will see 500,000 if well serviced, not so long with a turbo fitted.

kane077 wrote:Spend the coin, get it fixed properly before you cook it and bake the rings as well. It wont be reliable to just stick some crap in the radiator. Thats more of a get you home trick.

I have "chemiwelded" many a headgasket on petrol cars. We use either silver seal or Car-go seal up. The cargo stuff works a treat. Sometimes we double up on em for really bad ones.

Have seen cars go for an extra 150,000kms without trouble after a chemiweld job.
I have also seen cars where the gasket was to far gone to chemiweld.

Give it a shot and see what happens. just keep a close eye on your temps and levels.

I'll have to wait to see whats buggered when i pull it apart which will hopefully be on the weekend. If i was to fix up the motor how would i make it reliable and take the extra strain of forced induction? Or is that a hard ask of the 1hz engine? Cos if i do this job i never wanna have to work on the motor again...

There is no way you can remove the strain on the engine from forced induction. It will help if you intercool it and run minimal boost (10psi). There are no garuantees my friend!

kane077 wrote:There is no way you can remove the strain on the engine from forced induction. It will help if you intercool it and run minimal boost (10psi). There are no garuantees my friend!

No one has asked what boost he is running.

I am not a mechanic but i have spoken to 4 people in the last few months that all have 1HZ in 100 series cruisers and one of them has 750,000 k's on it since its been turboed.

They all have the Boost set at a around 10 - 12 psi, all of them had boost gauges fitted and all had pyros and turbo timers fitted.

Early on guys were getting the 1HZ and banging a turbo on them and boosting them right up, then driving them like it was fitted from factory. Anyone with half a brain could work out thats not going to work.

Your head is either cracked or head gasket is gone, simple as that. However when you get it back together you need to look at a few things.

1. What boost are you running
2. If the boost levels are correct do you have a pyro fitted
3. if you have a pyro are you driving it within realalistic pyro temps This is probably the biggest thing to look at other than boost).
4. Not really going to effect heads, but after long trips or heavy usage are you letting the engine idle to cool down
5. What is your service interval, all the guys that had the turbos fitted with all the gauges all serviced them regularly.(every 5000)

These are just some of the things that you need to look at after you rebuild it.

If you put it back together and your still running 15 or 16 psi and flogging it then your just up for another 4 grand in rebuilds!

I don't have a boost gauge but it's running standard sprintex pulleys so i've always assumed it'd be running between 8 and 10psi cos i don't think sprintex would have wanted to blow everyones motors up! I have a pyro and some info coming from sprintex and from the experienced bloke who made my pyro gauge was not to let it get over 650*C.
I thought that was a little high but very rarely get over 500*C which is only when loaded up and flogging around. I've been told my temps can be higher than turbos because the turbos take away some of the egt heat in heat soak.
I do have an intercooler sitting in the shed I just haven't fitted it yet Do they make a fair bit of difference to the longevity of everything do they? I thought they were just for more power? Also if it matters i'm getting between 90 and 105*C intake temps.

Thanks for all the help fellas!

The benifit with an intercooler is twofold. Lower intake temps mean better power and also lower temps in the combustion area and the tops of the pistons (which is where they crack). I have rebiult 2 1HZ engines only running 10psi with cracked pistons, admittedly one of them does cop a flogging! It might cost you 4grand if you biuld it urself but wiil blow out to nearly 10 grand if a workshop builds it as fuel pump, injectors and various other bits have to sent away to warranty the job.

Yep zee head is completely shagged! Each pre-combustion chamber is well and truly cracked and every piston chamber has at least on crack and one is so big it goes from the precom chamber to the valves! Not a very sturdy head at all i don't rekons... I'm not going to rebuild this motor as the heads seem to be sh*t!!!!
I'm thinking of a V8 swap at the moment so i can get the power i need with standard motor reliability. I'm thinking that because the 1hdt's are getting a bit old now and it'd be too hard to find one in decent knick?

Pre-combustion chamber cracks are normal and exceptable. Cracks in head.......................not so much. The trouble with engine conversions is getting it all to fit like it was factory. Ends up costing you a small fortune tying up all the loose ends to make it reliable. You could probly repair your engine for under 3 grand if you are handy on the tools. By the time you get the donor engine and the adapter kit there goes your 3large already and you still have to play with radiator fit up, powersteering hoses and electrical interface with your new donk. Having said that i have a customer who comes in with a chev diesel in his 80 series and it is sweet. He has had the diff ratios changed and the whole job is really well done. Best ive seen.

Yeah i know it'll cost a lot of money to do a swap but if i repair my motor i'm still stuck with a slow as all hell 1hz! Which i won't really want to put the supercharger back onto because it'll probably fry the new still weak designed head... hmmm so many decisions! Just as a side thought how much would i get if i parted out the whole car?

Dunno how much you would make off it. Probly less than half whats its worth if you got it running depending on what condition its in. To be honest, the head wont really suffer from being boosted its more the piston tops. I suspect that you may have gotten it a bit warm a couple of times and thats all it takes with the 1HZ. On top off that who can afford to run a petrol V8 4x4? Not me thats for sure! My GQ 4.2 with turbo gets around 12-14L per 100km and it doesnt seem to make much difference if its loaded or not. You wont get that from a petrol donk doing the same work.

Alrighty i've been getting some prices on different things,

To get my motor going again I'd need a new head ($1000 of ebay) rebuilt fuel pump ($1400) and should probably put new bigends in while I'm at it. And fit up my intercooler etc which would be about $300 odd to do.
What can I do to a 1hz head to make it crack proof? And are the precom chambers needed when the engine isn't N/A?

Nothing you can do to help the head out. Just let it idle down for a minute or so when you pull up from a drive. Yes the pre comps are needed as this is part of the squash area of the cylinder. Like i said earlier, the pre comps dont matter if they crack.

On a different note could I benefit from a new grind on the cam shaft? Or is that no-applicable to diesel motors?

Also I've heard alittle about HPC coatings on heads, pistons etc. Does this stuff actually work or is it a bit of a gimick? And how much would I be looking at for it on the head?

500,000 kms oh dear only another timing belt to go for me =[