PRADO 90 V6 Repair and Revitalize

[Gav Peter]

Wow, thats a clean engine - good work

IIRC, the air box on my T reg Colorado is round

 

[lekiboy]

Thanks, Gav...

Now, here are some leaks below that I do not know what to call:

1. Transfer case leak - I hope this is the same as the inner and outer oil seals that needs to be replaced. When my mecanic replaced the ATF, there seems to be no leak from the drain plug. At first look, it looks like it's coming from the drain plug.
REAR view:

FRONT view:

2. What's this? Is this still part of the differential? It looks like the leak is mud-like...
REAR VIEW:

SIDE VIEW:

I hope you can help me with these, guys. I do not want to just let people open the thing without making th enecessary preps on the parts.

Thanks!

 

[lekiboy]

After taking these pics, I went under again and checked the leak from the transfer case giving reference to another topic on transfer case leak.
There is no leak from the oil seal evidenced with this picture...

The leak is really coming from HERE and dripping down up to the ATF drain plug.

I also have no idea what is the leak coming from the one I have encircled (small) on the left...

Your inputs will be greatly appreciated.

 

[Ecky Thump]

I also have no idea what is the leak coming from the one I have encircled (small) on the left...

Your inputs will be greatly appreciated.

I can do this one, It's the prop shaft. The shaft is in two parts so that when you are articulating the shaft can stretch. There is a grease nipple on the shaft for topping up the grease. I do mine every time I have been off road. There is also a grease nipple on each UJ.
There should be a leak / evidence of grease at that point.
Forgot to say, If you grease the shaft be careful about how much you put in. One thing I was told years ago and I stick to it is;
Pump the grease gun until the two parts of the shaft start to part (we are talking a very tiny movement here) and that is enough

 

[lekiboy]

thanks, ecky thump. if my comprehension is correct, you were pointing at the small encircled item.

I am still wondering on the big encricled item why it is leaking an oil-like substance so much it goes up to the ATF drain plug. Am I looking at a major engine oil leak? IS that big item still part of the transmission? thanks.

 

[BobMurphy]

Hi,

This looks like a small oil leak in a hot, dusty climate that has crept all over the box. The 'mud' appears to be emulsified oil, probably from water splash in the road.

I wouldn't panic - just give the underside a thorough hot power wash and then keep an eye on it. It will be easier to see where its coming from when its clean.

It doesn't appear to be dripping so you won't lose much oil or do any damage while you investigate. Make sure all the oil levels are maintained.

It doesn't look like output flange oil seals, more like the silicone jointing compound failing between the transfer box and the rear cover. Try tightening the 8mm bolts that hold the rear cover on (12mm heads), but don't overdo the torque !

Let us know what you find. I have stripped transfer boxes but never touched an auto gearbox so don't know if they are prone to leaking.

Good luck.

Bob.

 

[Tommo&Claire]

I do mine every time I have been off road.

You lie like a hairy egg!!

 

[Ecky Thump]

[quote="Ecky Thump":276xw60u]I do mine every time I have been off road.

You lie like a hairy egg!![/quote:276xw60u]
Well, most times at any rate

 

[lekiboy]

Hi,

This looks like a small oil leak in a hot, dusty climate that has crept all over the box. The 'mud' appears to be emulsified oil, probably from water splash in the road.

I wouldn't panic - just give the underside a thorough hot power wash and then keep an eye on it. It will be easier to see where its coming from when its clean.

It doesn't appear to be dripping so you won't lose much oil or do any damage while you investigate. Make sure all the oil levels are maintained.

It doesn't look like output flange oil seals, more like the silicone jointing compound failing between the transfer box and the rear cover. Try tightening the 8mm bolts that hold the rear cover on (12mm heads), but don't overdo the torque !

Let us know what you find. I have stripped transfer boxes but never touched an auto gearbox so don't know if they are prone to leaking.

Good luck.

Bob.

Thanks, Bob.

Reading a lot of transfer case oil leaks stories in the web is a little too nightmarish for me.
I will try to clean up as much as I can tomorrow using a spray bottle with kerosene on it to clean the grease.
Yes, the leak seems to come out of the jointing line between the cover and the transfer box.

If I ask my mechanoc to remove the cover from the box and reapply silicone, will this be a major task? ANy recommendation for a very good silcone for this job?

Thanks again.

 

[BobMurphy]

If I ask my mechanic to remove the cover from the box and reapply silicone, will this be a major task? Any recommendation for a very good silcone for this job?

I'm afraid its not a straightforward job and there are some tricky bits you should be aware of.

I would prefer to do it with the transfer box on the bench, but it should be possible to do it in situ, though the extra hassle this causes isn't really worth the saving over removing the box.

Doing it with the box installed:

First:

Drain the oil.

Remove the rear propshaft and the bash plate from the bottom of the transfer box.

This gives you access to the rear output shaft Companion Flange . .

Knock out the 'stake' and undo the nut - it could be very tight, I had to use a 3/4" drive power bar with a scaffold pole over it

With the nut gone, the flange will pull off quite easily as its just splined on.

You now have access to the extension that carries the speedometer drive (the box is upside down on a bench here) . .

Personally, I would remove the speedometer drive before taking the extension cover off.

On my own box this was a ba***rd of a job, but on 'wotdabney's' box shown here it came out easily.

Then its an easy job to remove the extension cover.

The speedometer drive gearing is sandwiched within the cover and is driven by a steel ball bearing sitting in a hole in the output shaft - don't lose that (very small) ball

Now the tricky bit - and the reason I'd prefer to have the box on the bench - The end cover won't come off until the selector fork detent balls and springs have been removed along with the interlock plunger.

First remove both the screwed plugs and extract the spring and ball from each - I used a magnet.

You then have to move one of the selector forks well past its normal position so that the shaft comes out of the end cover (inside - you can't see this) allowing the interlock plunger to be extracted through the hole that held the detent ball and spring. This means removing the Transfer Lever turret and manually (i.e. with a big screwdriver) shifting the selector forward.

Putting it back is worse

You should now have these bits from the detent and interlock mechanism. . .

Next, remove the snap ring from around the output shaft bearing - the bearing won't pull off with the cover I'm afraid as its an interference fit on the shaft.

Almost there now . . . Remove all the 8mm bolts from the rear cover.

The cover will be well stuck down, plus it has to be extracted over the two output shaft bearings.

I heat the covers with a gas torch then use a couple of levers in convenient lever points in the castings to break the seal.

When the cover is off, this is what you see inside.

Note the ends of the two Transfer Selector Shafts - the notches to the outside are for the Detent Balls that 'index' the shafts in their different positions. The notches to the inside are for the interlock plunger. A shaft can only move when the notch in the opposite shaft is aligned with the plunger, thus, one can only move when the other is in a 'safe' position.


Now the faces can be cleaned up properly and new silicone applied before putting it all back together again.

Its tempting to just undo the bolts and try to inject some sealant into the joint, but I don't think that would work without damaging something expensive.

To be honest, if I was this far into the box I'd remove the front propshaft then take out the chain drive to the front.

This gives access to the oil pump filter and magnetic swarf trap - I'd clean them up just to be on the safe side.

Not for the feint-hearted


The very best of luck


Bob.

 

[lekiboy]

Thanks a lot, Bob. The pics and instructions were great.This will be a great reference for my mechanic once we decide to open it.

I just finished cleaning the transfer case and cover joint and this is how it looks like before and after . The yellowish brown matter on the joint was actually an epoxy-like subtance which I think was placed before by the previous owner/ mechanic. For now, this is the MAIN CULPRIT.
BEFORE

AFTER

I took more pics after removing and cleaning the small bash plate. Although this was really soaked pre-cleaning, it doesn't look like it is the source of the leak after cleaning.

I also took a pic of the edge of the ATF oil pan...It looks moist also. I just do not know if the leak is coming from bedisde it (transfer case). I don't know if this has a joint also.

Anyways, I will be observing the leak in a couple of days and confirm really where it is coming from. I will update everyone then.

Godspeed!

 

[BobMurphy]

Your second picture . . .

Is it my eyes, or is the upper bolt distorted and is that a crack in the casing below and to the right of it (there seems to be a bit of casting missing) ???

It looks as though someone has tried to repair a cracked case with Araldite or similar Epoxy Adhesive.

The Transfer box rear cover joint looks OK. hopefully you won't have to disturb it .

I would give it a really good scrub with some Industrial Cleaner (I use 'Ubik 2000') then just drive it and keep a close eye on it.

You should soon identify the source of the leak.


Bob.

 

[lekiboy]

Thanks, Bob.

Yes, I somewhat noticed the bent screw on the 2nd pic. I will check that again once I get back from work.
The crack seems small...probably due to time.

- After cleaning, can I reapply an epoxy to the areas leaking ( once confirmed)...I know this is just a temporary fix but if you can suggest a good epoxy grade or brand, that would be great. What we have here are ACE hardwares if I will check for imported brands.
- We also have epoxies here for metal..will that be better?

On the ATF oil pan...though I do not suspect the ATF to be leaking since the leaks were similar to grease oil, I suspect there is some leaks near it...does the transmission have another joint there or just another splash from the opoxied case...

Anyways, I will update all once I see new leaks.

Thanks again.

 

[BobMurphy]

There are breather tubes on the top of the Transfer box and the Gearbox (well, there is on the manual gearbox, I'm not sure about an Auto). They can produce oil mist that attracts dirt and eventually covers the transmission in oily mess.

Hopefully once its all clean you can rule that out.

I'm not an expert on glue, but here in the UK we use Araldite two-part Epoxy for repairs. I don't think it will work well on an oily joint though, jointing compound would be better, but it will have to be between the joint faces.

I wouldn't do anything until its all been cleaned and run for a couple of weeks, then re-assess it.

Bob.

 

[lekiboy]

Thanks, I will check all of these on SAT. I will post pics also.

 

[lekiboy]

There are breather tubes on the top of the Transfer box and the Gearbox (well, there is on the manual gearbox, I'm not sure about an Auto). They can produce oil mist that attracts dirt and eventually covers the transmission in oily mess.

Hopefully once its all clean you can rule that out.

I'm not an expert on glue, but here in the UK we use Araldite two-part Epoxy for repairs. I don't think it will work well on an oily joint though, jointing compound would be better, but it will have to be between the joint faces.

I wouldn't do anything until its all been cleaned and run for a couple of weeks, then re-assess it.

Bob.

Hi Bob,
I was able to check the vehicle last night but was unable to take pics. Anyways, I have seen leaks below and they are very minute after 4 days. I jus marked my old pic on the location. It looks like the previous owner just remedied the leaks with epoxy.
I am planning to clean the surfaces thsi weekend with kerosene and apply a steel epoxy to reinforce. Not much that I can do for now as dismantling is I think not worth it given the amount of leaks. I just have to check these on a weekly basis.

Thanks for your help. Godspeed!

 

[lekiboy]

Hi Bob and friends,

I was trying to find my ambient outside temp sensor in my Prado 5VZ but all efforts were futile.
All I saw were open ended wires and connectors. I tried looking for it in front of the radiator, beside it, on top of it....to no avail.
I even had some sample pics from teh web to check where it is.

I hope there's a good soul out there who can take a pic of the exact location of their sensor and a sample of the connector ( and post it here) that attaches with it? Thanks!
Am planning to fix my temp indicators in our inclinometer panel. I hope you can identify the open ended connectors as well.
Thanks again.

A. LEFTHAND SIDE OF THE TRUCK (perspective is while inside the truck)
NEAR the LEFT headlight

NEAR the LEFT fender

JUST in front of the radiator

B. RIGHT HAND side of the truck NEAR the RIGHT HEADLIGHT (bottom part)

 

[lekiboy]

I recently fixed the clunks when accelerating from a stop by greasing the outer slip yokes of the front and rear shafts...

I still need help on where the ambient temp sensor is located. I think I don't have one and planning to install a new one. Pls send a pic of your sensor and more importatntly the type of connector.

Thanks a lot!!

 

[lekiboy]

i cannot seem to find the fix for my faulty temp gauge..it kicks by an inch as soon as i start the engine then just stays on the lowest level...it rises by a few milimmeters once in a while but still. it stays just at those range.

i just recently replaced the thermostat with a new o ring, drained and replaced water and coolant and changed the temp sender/

has anyone of you experienced this? the engine is not overheating but i think i am wasting a lot of fuel...it just goes about 5kms. liter and has a white to grayish smoke after ignition from the exhaust pipe.

is there a way to check the connection of wires to the temp sender? is there another temp sending unit for the gauge?

thanks.

 

[lekiboy]

I just took out my throttle body and cleaned it together with the IAC..i also cleaned the MAF sensor..

i will try to drive it for a couple of kms later and monitor the consumption after a tank full of petrol. hopefully, i will be able to solve my hard starting and high fuel consumption.

but still, no solution for my cold temp gauge.