Freshening up ye olde vintage 1hz motor

[sunrk]

1hz motor in my 80 is about 2 k km's away from 700 k km's. Seeing as a replacement motor is probably not going to happen now I'm changing tack to freshening up the 1hz. I'll be doing the timing belt/tensioner, water pump, etc. as normal perhaps a new t/stat also.

I'll do valve shims again (last done at 600 k km's), and I'll be fitting a set of new fuel injectors also (with new return rail and inj seats). TBH I'm not a very experienced person with diesel motors so I can't tell just by listening if anything internal needs a look. I've never had the sump pan off but I keep the oil maintained well.

For those of you with high km 1hz's are there any other things you'd be looking into doing? I've had some people suggest bearings, and that I should get an oil test done as that can give clues about internals.

Note in the time I've had the vehicle the head has never been off the block, The injectors and injector pump were both done at about 510 k km's about 11 years ago.

 

[mudgudgeon]

I'd be inclined to leave well enough alone.
Do all the maintenance things you listed, timing belt etc.

Have an oil sample analysis done. If it's not showing bearing metal in the sample, I wouldn't risk letting the magic Toyota pixie dust out by changing bearings, head gasket etc.

If it's still running well and not burning oil, keep looking after it as you have been. 700k km, you've got a full life and then some from that engine.

If you open it up, you might find you need to do more than just put bearings in it

 

[veiloctane]

congrats 700 km that's awesome!!! you can always pull the pan and pull one of the bearings out and have a peek at it. I'm interested in what it looks like especially cyl #6

 

[Feistl]

Honestly I wouldn’t bother… do basic maintenance and drive it until it dies, then get a replacement motor.

The issue is, if you are going to sync money into the engine you want to do everything… pistons/rings, full set of bearings/seals, machine the block/heads, rebuild the injection pump, new injectors etc etc.

It’s going to be very costly and take a bunch of effort. If you only spend a couple of grand you still risk having the motor die from something you didn’t fix. Plus the labour/effort of removing the engine is high, so you want to do all or nothing.

 

[sunrk]

Good points. As I already have injectors I can't lose by doing them, and doing the shims is a messy but doable home job too. I have the tool for the shim job.

 

[ZCissner]

Basic maintenance, replace worn parts and oil sample from time to time. I've got 790,000km as of this morning on what is regarded as Toyotas worst gas engine (3vze)
and I am convinced it is because I have left it alone and all the Toyota magic is still trapped inside. Basic maintenance, replace worn parts and oil sample from time to time. overbuilt and underpowered.

 

[sunrk]

Basic maintenance, replace worn parts and oil sample from time to time. I've got 790,000km as of this morning on what is regarded as Toyotas worst gas engine (3vze)
and I am convinced it is because I have left it alone and all the Toyota magic is still trapped inside. Basic maintenance, replace worn parts and oil sample from time to time. overbuilt and underpowered.

Kinda like the 1hz in the diesel domain. Oil sampling is the one thing I haven't done in the time I've owned my 80 (from mid-2011).

 

[duncanrm]

Premptive water pump change if you havent been in there recently, and a freshen up/replacement of the viscous fan hub.. I'd also consider getting the radiator rodded out/replaced if its old.

 

[sunrk]

I did water pump with the t-belt job last time, so probably do it that way again. The radiator was new genuine 7 yrs ago, and so was the fan hub (never ever use cheap crap aftermarket ones!).

 

[mudgudgeon]

I did water pump with the t-belt job last time, so probably do it that way again. The radiator was new genuine 7 yrs ago, and so was the fan hub (never ever use cheap crap aftermarket ones!).

if you changed the t-belt at 100k km, and installed a new oem water pump, its overkill to change the water pump again so soon. Only failure I've seen was a dry bearing in a 25+ year old pump. they are a sealed bearing, so not particularly serviceable

 

[sunrk]

Righto lets focus on injectors as I have most (or all) new genuine parts - 6 x 11176-64010 injector seats, 6 x 23600-69055 injectors, 1 x 23761-17010 fuel return tube. I don't have the other fuel tube part 23762-17010 which I think is the fitting on the actual injector pump so it can probably be ignored for now.

As a side note with the injector pump I have a new genuine 22751-17470 wire assy for the fuel solenoid. The existing wire does not have the rubber boot. Is anyone able to indicate how to get the pin of the old wire to come out of the connector?

Anyway I started the motor yesterday to move the 80 for real estate people taking pics of my rented house since the owner wants to sell after being here 5 yrs and I'll probably get kicked out in Oct when lease runs out, and it felt like it was only running on 4 injectors initially, the 5, then all 6 after about 20 seconds. Ambient temp was pretty cool at about 5 c.

It's been doing this every time I start it *really* cold. I'm probably not waiting long enough for the glowplugs however I haven't touched the injectors ever and they were fitted 10 yrs ago when pump (which was leaking) was also replaced.

Since I have the parts might as well do the job.

Each injector includes a new nut and a small metal washer which I noticed is flat on one surface and round on the other. Is that a sealing washer for the bottom of the injector space at the tip seat (lower than where the brass washer sits)?

 

[mudgudgeon]

The 1hz will typically run rough in below 10⁰C temperature until there's a bit of best in the precombustion chamber.
Maybe a minute or two. I wouldn't judge it to harshly on an initial rough start.

Cycling the glow plugs a couple of times before firing the engine can help with initial start.

 

[mudgudgeon]

Each injector includes a new nut and a small metal washer which I noticed is flat on one surface and round on the other. Is that a sealing washer for the bottom of the injector space at the tip seat (lower than where the brass washer sits)?

Yes, it's a crush washer. Designed to squish and seal when the injector is tightened into place.

Make sure you get the old ones out. They can be a pain to get out