Will silicone hoses ease my cooling fears?

In my attempt to bring my van (95 kzh100g 2wd) back to life I’ve removed both seats so I’m able to work on the engine when it’s raining. Rather than start a new thread for every query I have I’ll just post them in here.

1) my map filter sensor appears to be gone. There’s a little clip on the intake manifold where it should be as far as I can make out. Should I replace it? I can’t seem to find any evidence of it.

2) I want to replace all the old cooling hoses with blue silicone hoses so I can tell them apart from oil ones and have piece of mind about the cooling system. Does anyone have any recommendations of kits to use? Or will the Chinese eBay ones work well? I’d like to replace the metal pipes in the cooling system and I’ve disconnected the rear heater lines too. Any input on this would be great. Also what are good alternatives to rubber pipes for the oil.

3) I cracked the silver intake pipe that goes over the top of the rocker cover because I’m not a mechanic and apparently not very good at adult Lego. How much of a mistake is this?

3) has anyone done a manifold clean? While I’m working my way down the engine I’ll be doing this. Seems like it just requires: removal, cleaning, replacing gaskets, reinstallation.

4) how do you safely disconnect fuel lines to move them out of the way?





In the quest to get my van registered I must overcome the following hurdles:

Oil leaks (suspected rocker cover gasket as the main culprit)

Leaking fuel injector pump (as per the threads on the forum I’ll take it out and try to replace the oring) any tips on this?

“EGR LEAK” I’d imagine this is an emissions issue. I can see that the egr pipe has a blacken bit that I’d assume that’s where the leak is. Hopefully it’s as simple as replacing the egr pipe. Also what’s this pipe I’m pointing to? Whoever worked on it last put an oversized generic pipe that’s leaking oil that I’ve got to replace but I’ve gone cross eyed from the Toyota EPC diagram




Servicing the rear drum brakes and the front brakes. No experience in doing this at all

Why am I doing all of this instead of paying for it to be repaired? I’m broke, I’m depressed and fixing it up makes me feel like I’m achieving something. Plus the mechanic I did take it to had it for 2 months and did nothing but flatten the battery and cause coolant leaks.

Any words of encouragement or tips are appreciated. Otherwise enjoy my struggles!

sorry cant help but am watching with intrest , I would like to do same with mine ,how do you find working on these ? , mine is a 89 h100

Only specific tips I can give are - silicon hoses not designed for street. They are porous, they seep coolant. You could loose maybe half a liter a year.

When you remove the fuel pump sensor don’t let it rotate while undoing the nut.

Just watch YT videos on brakes. HiLux or 4Runner brakes of that era are most similar.

What’s a “Map filter sensor”? You mean the map sensor filter? If that filter is missing your sensor will most likely be completely clogged with black gunk and either not working or, st worst, completely buggered. If that sensor is not working or clogged you’ll have seriously limited power and lethargic revving.

degs11 wrote:

sorry cant help but am watching with intrest , I would like to do same with mine ,how do you find working on these ? , mine is a 89  h100  

Well it’s much easier once you take both the seats out, being able to have a top down view of the engine with everything in reaching distance as opposed to wedging yourself up the seats is really helpful.

I did have to disconnect the air conditioning lines which I was a little nervous about but it went okay. It seems worth it to me, I’m okay with paying to have the aircon regassed at a later date if it means the accessibility of being able to view the engine.

Pete_nz wrote:

Only specific tips I can give are - silicon hoses not designed for street. They are porous, they seep coolant. You could loose maybe half a liter a year.

When you remove the fuel pump sensor don’t let it rotate while undoing the nut.

Just watch YT videos on brakes. HiLux or 4Runner brakes of that era are most similar.

Ah okay, from what I was seeing online I was starting to get the idea that the silicon hoses were a better alternative to replacing the oem pipes. The thinking is once I replace the pipes I won’t have to do it again so I guess I’ll avoid the silicon if it leaks. Would it be okay to replace the metal piping? Or can I give it a thorough clean

Pete_nz wrote:

What’s a “Map filter sensor”? You mean the map sensor filter? If that filter is missing your sensor will most likely be completely clogged with black gunk and either not working or, st worst, completely buggered. If that sensor is not working or clogged you’ll have seriously limited power and lethargic revving.

Yeah that’s what I meant. One of the reasons I’m bothering to do all this intensive stuff is because I noticed the power was really limited. I can barely hear the turbo anymore.

Take off that hose between the sensor and clean it out. Also the sensor pipe itself. But disclaimer: I don’t know what effect spraying brake clean or carb cleaner into the sensor might do. That sensor is one of the more critical parts. Astonishing how cleaning that pipe and replacing the filter can restore power. Without the correct reading fuel will not match air being forced in.

That broken manifold eye can probably be tig welded. There are 3 other bolts securing it but it’s under boost pressure so needs to clamp securely.

Metal pipes should clean up ok. If the ends are corroded to the point of failure (holes) not sure options are. Don’t know if they’re still available as replacements. You’ll need to delve into the 4 dimensional puzzle that is the fische based diagrams. (I’m old enough to have referred to microfische records.)

Pete_nz wrote:

Take off that hose between the sensor and clean it out. Also the sensor pipe itself. But disclaimer: I don’t know what effect spraying brake clean or carb cleaner into the sensor might do. That sensor is one of the more critical parts. Astonishing how cleaning that pipe and replacing the filter can restore power. Without the correct reading fuel will not match air being forced in.

That broken manifold eye can probably be tig welded. There are 3 other bolts securing it but it’s under boost pressure so needs to clamp securely.

Metal pipes should clean up ok.  If the ends are corroded to the point of failure (holes) not sure options are. Don’t know if they’re still available as replacements. You’ll need to delve into the 4 dimensional puzzle that is the fische based diagrams. (I’m old enough to have referred to microfische records.)

So that little black plug thing is the sensor but not the filter?


I’m scared to ask what what fische based diagrams and microfiche records are which probably means I’ll need to know

Ha I was just referring to the way Toyota catalogue their parts in convoluted layers but you don’t get to see the layers as a whole. Fiche is just the plate microfilm method of storing those diagrams. All you need is digitised into what you see online.

The correct Toyota name for the sensor is Turbo Pressure Sensor which functions as a MAP sensor. It’s written on the yellow label. There should be a filter between the manifold and the sensor. Pull the hose off at the manifold and black sludge will probably dribble out. The filters can’t really be cleaned that effectively so discarding them is a very short term solution. In Japan they’re about ¥700 (about NZ$7.50) but here in NZ Toyota charge something close to $40 each for them.

Do not despair this forum has the answer to everything example the filter for the MAP can be replaced with a inline paper gas filter as on lawn mowers etc about $1 , use MAF cleaner on the MAP and lines , high mileage SC diesels will need manifold cleaning scraped gung of my inlet valves by the spoonfull unblocked the MAP pipe too. MAP meter available on ebay £9.00. Biggest issue yet was the ECU these go bad around this age not available anymore but usually its leaky capacitors 7 of them bout $8 each problem is getting someone to fit them easy if you have the know how, symptoms are bad starting and clicking from spill valve. O the joys of old vehicles I am 76 and still at it.

Hello Moonroofed

My 2p

1 – no idea my van doesn’t have an ECU like the 1KZ.

2 – sadly the metal pipes for coolant are prone to failure. I’ve heard of folk replacing the steel lines with copper. This should not be too much of an issue if you are using a brass and copper radiator and are running the right coolant for this type. The hardest thing with replacing the steel piping is getting a flare on the pipe end so the rubber hose stays attached and not crushing the pipe. Alternatively look in the EPC (see my first post in my show us yours section for details) for parts. If you can’t make these and want to replace them then the OE parts might be the only option. Constant tension clamps are generally better than the worm drive ones, I think. As you’ve disconnected the rear heating you don’t want long potentially failure prone tails. Shorten any unused piping. You might also be able to replace a section of rubber - steel - rubber hosing with a longer length of rubber, but remember the steel piping was probably chosen for wear or abrasion resistance. The only silicone hose I’m planning on swapping to would be to replace the corrugated air one between the air cleaner contraption under the driver’s seat and the aluminium manifold part above the engine. Unsure if your engine also has this but the OEM parts are very expensive and a length of silicone hose will do nicely for this. It just holds air. In Aus, patrolpart (also navarapart) sells a complete coolant hose kit for those vehicles. I’d be looking for the same for the hiace you have. The kit (if available) is likely much cheaper that separate hoses and you could then keep the ones you have as emergency spares.

3a – If you are loosing boost from the manifold with the cracked bracket then you either need to clamp it somehow, seal it somehow, replace the part or take it to an aluminium welder who will fix this quite cheaply.

3b – I’ve not removed the manifold that is attached to the engine block, but I have cleaned every part of the air intake system. This has either gone in my untrasonic cleaner after scraping with screwdriver or sim and brake clean or has been soaked in big tubs of water and brushed clean. When I do the intake on the engine then I’ll do as you put in your post. Be careful taking any bolt or stud out of the engine as these have likely seized and gone brittle. Heat plus penetration oil is a general must. Unless the manifold really needs removing I’d be inclined to leave alone. Is the task worth the potential pain of a snapped bolt (though the exhaust side is typically worse to remove).

4 – depends on how thorough you need to be, how far you are removing them and for how long. Are you talking about flexible or solid lines?

The rear drum brakes on practically every Toyota are the same or very similar. Look at the post I mention for suggestions for manuals and also look on You Tube. Timmy the Toolman makes great videos on Toyotas and these are transferrable to other related vehicles. Faye Hadley has also done loads of very relevant videos.

Nobody will ever do a better job than you do on your own vehicle. It might take you longer and possibly cost more in the short term, especially if things go wrong, but the idea is to not make the same mistake twice and buy the tools you need to do the job and the next one.

HTH!!

JT69 wrote:

Do not despair this forum has the answer to everything example the filter for the MAP can be replaced with a inline paper gas filter as on lawn mowers etc about $1 , use MAF cleaner on the MAP and lines , high mileage SC diesels will need manifold cleaning scraped gung of my inlet valves by the spoonfull unblocked the MAP pipe too. MAP meter available on ebay £9.00. Biggest issue yet was the ECU these go bad around this age not available anymore but usually its leaky capacitors 7 of them bout $8 each problem is getting someone to fit them easy if you have the know how, symptoms are bad starting and clicking from spill valve. O the joys of old vehicles I am 76 and still at it.

I bought this van that wasn’t running because I googled the symptoms and this forum told me it was a bad ECU. Because of that I was able to get the van for a steal and after paying for ECU repair it was up and running again! I’m looking forward to cleaning the scunge from the manifold!

Pete_nz wrote:

Ha I was just referring to the way Toyota catalogue their parts in convoluted layers but you don’t get to see the layers as a whole. Fiche is just the plate microfilm method of storing those diagrams. All you need is digitised into what you see online.

The correct Toyota name for the sensor is Turbo Pressure Sensor which functions as a MAP sensor. It’s written on the yellow label. There should be a filter between the manifold and the sensor. Pull the hose off at the manifold and black sludge will probably dribble out. The filters can’t really be cleaned that effectively so discarding them is a very short term solution. In Japan they’re about ¥700 (about NZ$7.50) but here in NZ Toyota charge something close to  $40 each for them.

The sensor hose was connected direct to the manifold. I’m cleaning the sensor as best I can but I did accidentally spray brake cleaner on it so I’m hoping it was so gunked up that it wasn’t damaged. So I should buy the filter, it looks like a little top hat right? Connect it to the manifold then the sensor to it?

LH119V wrote:

Hello Moonroofed

My 2p

1 – no idea my van doesn’t have an ECU like the 1KZ.

2 – sadly the metal pipes for coolant are prone to failure. I’ve heard of folk replacing the steel lines with copper. This should not be too much of an issue if you are using a brass and copper radiator and are running the right coolant for this type. The hardest thing with replacing the steel piping is getting a flare on the pipe end so the rubber hose stays attached and not crushing the pipe. Alternatively look in the EPC (see my first post in my show us yours section for details) for parts. If you can’t make these and want to replace them then the OE parts might be the only option. Constant tension clamps are generally better than the worm drive ones, I think. As you’ve disconnected the rear heating you don’t want long potentially failure prone tails. Shorten any unused piping. You might also be able to replace a section of rubber - steel - rubber hosing with a longer length of rubber, but remember the steel piping was probably chosen for wear or abrasion resistance. The only silicone hose I’m planning on swapping to would be to replace the corrugated air one between the air cleaner contraption under the driver’s seat and the aluminium manifold part above the engine. Unsure if your engine also has this but the OEM parts are very expensive and a length of silicone hose will do nicely for this. It just holds air. In Aus, patrolpart (also navarapart) sells a complete coolant hose kit for those vehicles. I’d be looking for the same for the hiace you have. The kit (if available) is likely much cheaper that separate hoses and you could then keep the ones you have as emergency spares.

3a – If you are loosing boost from the manifold with the cracked bracket then you either need to clamp it somehow, seal it somehow, replace the part or take it to an aluminium welder who will fix this quite cheaply.

3b – I’ve not removed the manifold that is attached to the engine block, but I have cleaned every part of the air intake system. This has either gone in my untrasonic cleaner after scraping with screwdriver or sim and brake clean or has been soaked in big tubs of water and brushed clean. When I do the intake on the engine then I’ll do as you put in your post. Be careful taking any bolt or stud out of the engine as these have likely seized and gone brittle. Heat plus penetration oil is a general must. Unless the manifold really needs removing I’d be inclined to leave alone. Is the task worth the potential pain of a snapped bolt (though the exhaust side is typically worse to remove).

4 – depends on how thorough you need to be, how far you are removing them and for how long. Are you talking about flexible or solid lines?

The rear drum brakes on practically every Toyota are the same or very similar. Look at the post I mention for suggestions for manuals and also look on You Tube. Timmy the Toolman makes great videos on Toyotas and these are transferrable to other related vehicles. Faye Hadley has also done loads of very relevant videos.

Nobody will ever do a better job than you do on your own vehicle. It might take you longer and possibly cost more in the short term, especially if things go wrong, but the idea is to not make the same mistake twice and buy the tools you need to do the job and the next one.

HTH!!

That does really help! Thanks for the encouragement. I’ve definitely made a bunch of mistakes despite trying to be careful but they’re all mistakes I’ve learned from.


I haven’t had an in-depth look at the metal coolant pipes yet. Hopefully I can just clean them up but I’d like to do a good thorough clean so I don’t have to do it again. I’m happy to use oem parts where necessary though. It’s tricky because there’s a bunch of tasks at once so I’m doing my best to work thru them methodically instead of having a bunch of unfinished things at once.


I don’t think I’ll take the exhaust manifold off this go around but I’d look into replacing it and the exhaust in the future. The actual exhaust leak is further down on the flexible bellow part. I’m more interested in the intake manifold, gaskets, getting it out so I can take the fuel pump out and repair that at the same time. While also doing a timing belt change

https://photos.google.com/photo/AF1QipNbKMNHoSkhmsQ7ZEmVnCjkMrmg-HUUZTOo7Kw6

good tip with the seats , there is so much pipe work on these hard to even see whats going on still with the help of this forum feel a bit more confidend

Any tips on the best way to clean all this dirt and oil once I do the rocker cover gasket? Also this might be a dumb question but is that piece of foam stuff next to the fuel pump factory? I saw another photo of a van engine that had the same thing so I’m just wondering

For cleaning - I've used an aerosol can of brake cleaner - but avoid getting it too near the belts, just in case.

^ill end up doing the belts anyway but will do!