1UZ in Thai longtail boat

The 1UZFE EGR Delete Kit is available for sale here.
HOW LONG WAS ADAM IN EDEN (few hours)
Following on since it started brilliantly without coolant.
Yesterday:
Connected up the electrical fans on the oil cooler and the thermo switch on the radiator.
Tanked up with coolant - 11-12 liters.
I have a significant voltage drop somewhere in the ignition circuit so must use a jumper cable from battery to close to the ECU loom in order to start.
Started immediately with flying honors. Running SMOOTH AS SILK , as we say, on all 8.
Adjusted idle to 450/500. Checking gauges working.
Stop / start a few times, checking a bit. All 5 oil cooler fans working as they should.
Starting and let it run, want it up to 80+ degrees in order to check that thermo switch and radiator fan relays are working.

After 15 + minutes or so, white smoke spotted from the exhaust pipe serving cylinders 2 and 4. (The exhaust is normally totally invisible.)
What now? Checking by hand the pressure of the exhaust coming out of the pipes, sure - cylinder 2 or 4 not working.
Checking spark plug 2 and 4, they fire OK.
Off with air intake conduit - checking injectors and ther plugs - sure enough - black wire broken in one of the injector plugs.
OK, searching scrapyards for plugs today.

Conclude to run on 7 until warm so that I at least can tick off the thermo switch and the relays as being OK.
Start? Nee way. Stone dead. Not one cylinder firing. Checking wiring around coils and igniters - seem OK. Still stone dead.
Have a spare ECU that I can put in and test next time I decide to have a go.

Getting a bit bored with problems now.
Seems Murphy is following med closesly most of the time and sometimes (too often) he catches up.
 
Further to the above;

fixed injector plugs

fixed problem with starter, a couple of parts changed at a starter/alternator workshop
starter running fine

took days to find and sort out some electrical problems in the 12V supply chain

all put together,
starting easy peasy running almost as silk, 1 cylinder coming and going a bit
running it warm

hmmm,
coolant not circulating, engine hot and radiator cool

sorted after advice from Gloverman, opened the bleeder on the top of the cooling system anf filled up with
about 4 pints of coolant,
circulating OK no, fan relays OK, fans start and stop as they should

happy? not quite, see next post
 
ENGINE OIL LEAKING INTO EXHAUST PIPE, ADVISE SOUGHT

Months ago I had the same problem.
Ordered spare parts, oil seals for the valve stems and a few other pieces it took months to get hold of
and 1 month and 5 days to get through Thai Customs.

The running of the engine in the past few posts is really test running after having changed all the seals
and put things together again.

Now, yesterday after having fixed the circulation of the coolant I discovered engine leaking into one exhaust pipe,
the pipe serving the two front cylinders on RH side.
(haven't checked the plugs yet to see if problem is linked to one cylinder only, but I am reasonably sure of that, must find out which one)

What can cause engine oil leak into exhaust pipe?
* Oil seal problem, sure, but all seals are brand new Toyota seals. (of course could have made a mistake inserting seals in one cylinder)

* Could worn piston rings be a possible cause of this?

* Other possible causes?

I can add that the 8th cylinder is more likely to work with a cold engine and low revs.
That matches low oil pressure and thicker oil.

Any feedback would be much appreciated.
 
A worn valve guide would allow the valve to move around and that movement would allow oil past the valve stem seals.

For rings to allow that much oil through they would be really worn and the rest of the engine would be showing signs of wear.

Other than that I can't see where the oil would come from.

If it was a faulty PCV valve oil would go to all cylinders.
 
Melvin, when these engines start having internal issues, it may be easier/cheaper to get another engine. They're fantastically built and reliable, but they're also so cheap at junkyards that it's really not worthwhile to go into them and fix internal problems, unless you're just doing it for the fun of it. I don't know their availability in Thailand, but here in the USA, a good used long block won't cost much more than $500-$750.

I would get another long block and just put all your specialised marine accessories on it and not look back. The old block might make a really good boat anchor for you :)
 
A worn valve guide would allow the valve to move around and that movement would allow oil past the valve stem seals.

For rings to allow that much oil through they would be really worn and the rest of the engine would be showing signs of wear.

Other than that I can't see where the oil would come from.

If it was a faulty PCV valve oil would go to all cylinders.

Thanks for that.

The PCV/CPV stuff is brand new, Toyota issue.

When the engine is running OK the exhaust is really invisible.
I have to move around and find the right angle to the sun in order to see anything coming out of the pipes.
So it is probably not that worn.

Now, valve guide:
Is this some kind of cylinder/pipe that is pressed into the cylinder head? Or is it screwed into place?
Can it be changed with normal tools after removing the camshafts?
Or is it required to take the cylinder head off? Must specialised tools be used?
A DIY job or is a workshop needed?
(provided I can get hold of some, guess all 4 should be changed)

---
Ater thought;
If a piston ring for some reason should be broken in two, I assume that would let oil pass upwards.
However, I assume that a broken ring would result in some very unpleasant sounds coming
from the engine
Is that assumption right?
 
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Melvin, when these engines start having internal issues, it may be easier/cheaper to get another engine. They're fantastically built and reliable, but they're also so cheap at junkyards that it's really not worthwhile to go into them and fix internal problems, unless you're just doing it for the fun of it. I don't know their availability in Thailand, but here in the USA, a good used long block won't cost much more than $500-$750.

I would get another long block and just put all your specialised marine accessories on it and not look back. The old block might make a really good boat anchor for you :)

Yes, thanks, point well taken.
That thought has crossed my mind several times.

It is not really fun anymore. I have had too much problems over the past year. Murphy is constantly at my heels.

1UZs are plentifull in Thailand. Popular for being swapped into Toyotas and some older BMWs and various pickups.
Lots of scrapyards have 1UZ, many scapyards do swaps as well, and gasoline to gas conversions.

Haven't seen short/long blocks around, they sell complete engines ready for swap.
Comes with ECU, ignitors, bellhouse/automatic gearbox etc, rare to see radiators and fans though.
And you get no info re the engine at a scrapyard, dont know which year, dont know which car.
No knowledge of the condition.
They start the engine for you at the scrapyard if you are interested, but thats it.

The cost for a pre VVT 1UZ is about 25000 Thai Baht, about 6-700 USD I would guess.
The challenge for me would be the electrical stuff, reducing the loom to what is needed. Not sure how to handle that,

Its not only adding my marine stuff, its also removing Toyota stuff that is not needed.


PS
Have just spent an hour on the terrace with a beer thinking through a changeover to
a new engine. Not so small job actually, quite a pile of work and also some cost involved.
Can't haul the engine at home, no lifting arrangements.

2kms down the canal there is a diesel engine and longtail workshop where I can haul
and could probably have two engines there and do the work,
Would need to make up two engine benches though to lift them off the ground.
And benches must have double piping in the legs so that the engine can be lifted high
up when flooding is threatening. Half a meter and even 1 meter of water above the
workshop concrete floor happens.

Anyway, my longer term plan is; when (if) the 1UZ is running OK, is to import a 1VD
from the US, (Toyota V8 diesel twin turbo 4500 cc).
And use the 1UZ as a spare engine.
Even though the 1VD is common rail it is bound to have way less cabling than the 1UZ.
1VD has great torque, about 700 Nm, which is always good in a boat and about 260/270 hp.

The rpm/torque curves for 1VD are not as you want them for a boat, but there is plenty Nm.
(The 1UZ curve is much better for a boat)

dreams dreams
 
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I think John has the solution.

Buy a second engine and swap the wiring from your existing engine onto the replacement.

It will be cheaper and quicker to swap than pull heads in the boat.

Replacing valve guides is a specialised task and requires the old guide to be hammered or pressed out and new guides to be pressed back in. The guides would need reaming to the required size.

I would think you would get the engine out, swap the wiring and engine back in in two days.

You could keep the old engine for spares.

The V8 diesel has a poor reputation here in Australia as they tend to blow up.
 
I think John has the solution.

Buy a second engine and swap the wiring from your existing engine onto the replacement.

It will be cheaper and quicker to swap than pull heads in the boat.

Replacing valve guides is a specialised task and requires the old guide to be hammered or pressed out and new guides to be pressed back in. The guides would need reaming to the required size.

I would think you would get the engine out, swap the wiring and engine back in in two days.

You could keep the old engine for spares.

The V8 diesel has a poor reputation here in Australia as they tend to blow up.

Yes, I think you are right about cost in the longer run.
Btw, my neighbour talked to the mechanics where he works (repair shop for crashed cars, neighbour is the paint job man),
they also doubted piston rings very much and landed on valve guides.

Yes, just swapping the wiring could probably be done in 2-3 days. But there is an awfull lot more that need to be transferred.
Bellhouse, clutch and gearbox - right now I don't remember the arrangements for thrust bearings and the interconnection between crankshaft and gearbox.
Oil cooler arrangements need transfer.
Shackle arrangements at the back of the engine for hooking up wire that prevents the longtail from bending.
Brackets for acryllic "raincoat" over engine and Toyota fuel filter.
Radiator/fans arrangements, a lot of steel there which need to be fixed to the engine on both sides, low down and high up.
And the large main steel frames for the engine itself, the stuff that links the engine to the boat, needs some drilling and is a precision job,
anything here out of lineup the engine will either not balance properly (up and down) or it will not follow the centre line.
And I am sure I have forgot the odd issue.

If a replacement 1UZ is exactly the same as what I have then this job isn't too bad, but the odd minor difference from what I have might result in redesigning
some of the above, machining the steel stuff etc etc, find new solutions for hooking up etc. Takes time.

I have a Toyota shop just up the road, will drop by there today to buy some gasket cement.
Will enquire about cost and availability of valve guides - curious about that.

As for doing actual valve guide work that I view as no challenge really and dead cheap.
In and around Bangkok you just wouldn't believe how many workshops there are for doing complete engine overhauls and refurbishments,
the number is out of this world.
(same goes for shops selling car batteries, 7-11s, ATMs, scrapyards - they are everywhere)
 
If I were in your position I would be looking for the same model engine (as in out of the same car) as this would give you the same belt drive, sump location, engine mounts and bellhousing (there are two bellhousings for the 1UZ).

By getting the same series of engine your wiring would swap over and use the same ECU so this would save re-doing a lot of stuff.

Plan ahead and it will be simpler than you expect.

I know with my own car swapping engines is a real pain but I can still do it in a couple of days.
 
If I were in your position I would be looking for the same model engine (as in out of the same car) as this would give you the same belt drive, sump location, engine mounts and bellhousing (there are two bellhousings for the 1UZ).

By getting the same series of engine your wiring would swap over and use the same ECU so this would save re-doing a lot of stuff.

Plan ahead and it will be simpler than you expect.

I know with my own car swapping engines is a real pain but I can still do it in a couple of days.

.... and of course the whole exhaust system with its non Toyota brackets would have to get shifted over ...


Yes, thanks Zuffen, I think that is sound advice.
Think I know what to look for, the sump placement is an easy discriminator, then the piping serving the injectors should indicate generation,
physical placement of the LH coil is also an indication for me,
if these things fit - then ask to check the ECU part number (the ECUs are normally stored away from the engines in the yards)

did spend a couple of hours thinking through the harness swap, did some sketching etc - think its doable

must see the diesel/longtail mechanics down the canal and check if I can haul and store there and work in their shop, really big shop
if so must put together two benches on wheels to get the mills off the floor


re bellhouse
the Toyota flywheel casing/bellhouse and gearbox would be taken off
and replaced by Isuzu flywheelcasing/bellhouse clutch and Mazda gearbox


btw,
yesterday I checked up on the valve guides, availability and price, availability was zero, the price, however, was quite OK,
not damaging like many other Toyota parts
 
GROUNDING/EARTHING OF CYLINDER HEADS


A few days ago I read on a 1UZ related www page that it was highly recommendable to ground each ctlinder head in addition to the grounding of the engine block.
It was claimed that such grounding would greatly reduce the risk of problems with the injectors, (and a couple of other items I have forgotten).

Is this something you guys practice? Individual grounding of the cylinder heads in addition to the block.
 
Melvin, this is true, IMHO. Even though the heads "should" be electrically connected to the block by way of all the head studs & nuts, nothing beats a nice chunk of copper braid between them.
 
Melvin, this is true, IMHO. Even though the heads "should" be electrically connected to the block by way of all the head studs & nuts, nothing beats a nice chunk of copper braid between them.
ok, thanks, will do that then, will not be braid but AWG10 or AWG2 cable, depending on available space between the back of the cyl heads and my engine mounted negative buss.
 
Don't scrimp on the size. Ferrari uses the copper braid between heads & block, and theirs looks to be about AWG 2 or larger. There are at least 3-4 separate large grounds on their engines - one thing their electrical engineers apparently got right. The rest of the electrical system on a Ferrari is appalling.
 
No no, I am not mean when it comes to cables.
But a 10 gauge multistrand copper ain't no mean grounding either, there are not that many amps flying around in the cylinder heads.
I assume that the cylinder head bolts are made of some kind of steel, that is mean grounding. Steel is not a good conductor.
 
If I were in your position I would be looking for the same model engine (as in out of the same car) as this would give you the same belt drive, sump location, engine mounts and bellhousing (there are two bellhousings for the 1UZ).

By getting the same series of engine your wiring would swap over and use the same ECU so this would save re-doing a lot of stuff.

Plan ahead and it will be simpler than you expect.

I know with my own car swapping engines is a real pain but I can still do it in a couple of days.

I ended up, for now, doing something in between spare parts and replacement engine.
I bought a pair of replacement cylinder heads, complete with covers and cams and valves and the lot.
(mostly because this is much quicker than arranging the needed framework around having two engines,
and I am getting somewhat impatient now)

Will see where this brings me.
 
SYMPTOMS CAUSED BY FAULTY/FLAKY IGNITORS:

I have no reason pt to suspect that the ignitors I have are playing up somehow.
However, they have been under water for about 25 hours at a depth of 20-25 meters, (some pressure there).

Hence, any hints on symptoms to expect if they start playung up?

(got hold of a pair of "previously owned" ignitors from the nearest scrapyard, dead cheap,
paid the equivalent of 3 and a half bottle of small beers (beer bar price) for the pair)
 
If one failed it would drop 4 cylinders.

A simple test I do is start the engine and let it run for 10 seconds and shut it down.

Using the back of my fingers I feel the exhaust headers to determine which cylinders didn't fire and that tells you which distributor isn't firing and will lead you to the ignitor that has failed.

If you have spares just use them and don't invite the problem of one or both failing.
 


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