How bad is 285 psi compression in a turbo 3B?

[RufusTheDufus]

The UPS guy dropped off my compression tester today. I was able to take some readings. 289, 292, 307, 285. So they're at the low end of the spec. Engine has 368,000 kms on it. I have no idea how much of that was with a turbo. A half-dozen drops of 0 - 30 ELF synthetic oil into each cylinder brought the compression numbers up over 400 psi.

So how bad is this? Should I be concerned about the engine failing at some point?

[brownbear]

Did you do the compression cold or hot?

I thought the FSm said to do it hot. Then it's accurate to normal driving conditions.

[Otterav]

Ditto,
Ya gotta do it with the engine at operating temp, you might even have to start and run between cylinder tests. The other thing to make sure you are doing is open the throttle butterfly all the way. If you didn't do it this way your results are not accurate.
eric

[RufusTheDufus]

I did it hot. I had some errands to do and ran it out on the road for 20 minutes. Parked it in the garage, Unplugged the EDIC, pulled the glow plugs and cranked it for each cylinder with the pedal to the floor. It couldn't have taken more than 15 minutes to do the whole thing.

I read the FSM prior to doing the compression check.

[wesintl]

285 is min spec so I would think your ok unless you have poor power and are burning alot of oil. Otherwise it's fine.

[roscoFJ73]

If you want it to last keep the revs down ,particuarly for long periods on the highway.

[M John Galt]

That engine has specs like a 50 to 60 year old human. Tired, still in reasonably good shape, but can't compete with a kid in their 20s.
Concerned about how long it will last? How long do YOU expect to live?

If the rest of the truck is in really good shape then overhaul the engine, if not drive it till it dies at about half a million kms.

[RufusTheDufus]

When these engines die is it a slow death with lots of warning signs or something a little more sudden? The body is in pretty good shape. We were hoping to use it for camping trips to the southwest driving from Maine. (5,000 mile+ trips with lots of highway driving.) I guess that's not such a good idea without an overhaul.

[roscoFJ73]

Originally Posted by RufusTheDufus

When these engines die is it a slow death with lots of warning signs or something a little more sudden? The body is in pretty good shape. We were hoping to use it for camping trips to the southwest driving from Maine. (5,000 mile+ trips with lots of highway driving.) I guess that's not such a good idea without an overhaul.

IMO you do not have a serious problem yet and providing you dont over stress the rings it will be fine for a few more camping trips yet
Highway trips will be fine as long as you keep the rpms down.

Its already dying a slow and graceful death as the compression figures are close to one another.
Now you know its going to die it will give you a year or 2 to line up an engine rebuilder.
The engine kits for these are cheaper than some gassers.

I guess the next signs will be increased blow by ,oil usage and harder starting in the cold.

Another way of monitoring your engines condition will be to do a comp every few months or so

[RufusTheDufus]

I think I'll start planning on a rebuild. I'll order a kit from roodog on Ebay and find a shop to handle it. I know there's a few diesel shops around the specialize in logging equipment engines but they should be able to do the machine work on the 3B too.

[Ron R]

Originally Posted by RufusTheDufus

I think I'll start planning on a rebuild. I'll order a kit from roodog on Ebay and find a shop to handle it. I know there's a few diesel shops around the specialize in logging equipment engines but they should be able to do the machine work on the 3B too.

No objections against a rebuild

But keep in mind that this engine is just loosing it's optimum performance. That's all.
As long as you don't need that there is no real need for a rebuild.

If you want to carry out that rebuild now because you're afraid the engine will get damaged because of this degration, then don't worry.
This kind of wear is 'healthy'. No parts will break or suffer damage because of this.
As long as performance is sufficient to you and oilconsumption is within reasonable limits you can postpone the rebuild. Enjoy another 100k k's or so and then do the rebuild.
Then you will have more value for money.

[RufusTheDufus]

I actually have an extra turbo 3B engine that only has 40k kms on it. (It used to be Lumpy's.) I also have an HJ45 Troopy on the way from New Zealand with a tired 2H in it. My plan was to put the rebuilt engine into the HJ but I think I'll end up tossing it in the BJ. Then I'll rebuild the BJ's motor for the HJ. (Does this make any sense?)

The HJ is more of a long term project. It doesn't need an engine for a while. The BJ is something we plan to use this summer for a cross country trip lasting 8 - 10 weeks. I don't want to have to worry about reliability issues. Since I have a spare fresh engine I might as well make use of it.

[mac]

That sounds perfectly sensible. I would consider putting a six back in that troopy though. Maybe a 1HZ or 1HD-T.

[RufusTheDufus]

A turbo 3B should do just about as well in the Troopy as a normally aspirated 2H, no?

[Ron R]

Originally Posted by mac

That sounds perfectly sensible. I would consider putting a six pack in that troopy though.

A six pack ?

[mac]

Yes, actually I would prefer a turbo 3B over a na 2H. Given the weight of a troopy however, I would prefer a 1HZ-T or a 1HD-T and I only suggest it because you'll be pulling the 2H anyway. When you factor in the cost of rebuilding your 3B, add to that what you can sell it for as is- you may come near to the cost of picking up a newer Toyota diesel and be much happier with the performance.

[RufusTheDufus]

How does the fuel economy compare. turbo 3B vs. 1HZ or 1HD?

[roscoFJ73]

Originally Posted by RufusTheDufus

How does the fuel economy compare. turbo 3B vs. 1HZ or 1HD?

The 3B would probably use at least 10% less but a 6cyl is much smoother and has longer legs. Its the long trips where the 6 cyls come into their own
Even without a turbo ,a 1HZ cruises beautifully at 70 mph and 2800. A good 1HZ can attack most hills without too much loss of speed although thats relative to the terrain in your area

[M John Galt]

The 1HZ has slightly less power than the 13B-T, but the economy is about the same. If you operate at sea level there isn't much difference, but over 2000ft the turbo makes a big difference.

[RufusTheDufus]

We'll be vacationing in the four corners area and Crested Butte, CO. The turbo will certainly help.

[mac]

Originally Posted by M John Galt

The 1HZ has slightly less power than the 13B-T, but the economy is about the same. If you operate at sea level there isn't much difference, but over 2000ft the turbo makes a big difference.

Actually, it's the other way around- the 13BT lists at 120HP and the 1HZ @ 135HP.
The 13BT is a nice engine but if you were considering a swap you may as well go for a cuurent engine and one that produces the most bang for buck. The 1HZ is a good choice in that respect- turbo it and it reportedly will sing you a wonderful tune.

As for fuel economy- I'm not a tight #'s crunching type but have had many 3B's, a 13BT and now a couple of 1HD-T's and the economy is close. It's within a few MPG's. My 80 is the heaviest and only full time 4wd of my Cruisers and I still can attain a respectable 23MPG. My Bj60 with a 3B was getting approx. 26MPG. Not a big diff to me esp. considering the power gains- 90HP compared to 160HP.

[RufusTheDufus]

I guess I should look into how difficult is it to get one of these engines in the U.S.

[M John Galt]

Originally Posted by mac

Actually, it's the other way around- the 13BT lists at 120HP and the 1HZ @ 135HP.

Believe whatever numbers you want, I've driven both at 2500', I was speaking to real power not theoretical. BTW both trucks have about the same 100,000 km, with the same compression to spec.
... and your actual experience behind the wheel?

[lumpy70]

I think your compression tester is off by at least 5 lbs. Why? Because diesel will not fire below 290 lbs. If your truck runs, then good. If you are satisfied with the power and performance, also good.

I rebuilt mine when it was at those numbers, but the truck barely ran so I had little choice.

Factory spec is 420 lbs per cylinder.

Craig.

[mac]

Originally Posted by M John Galt

Believe whatever numbers you want, I've driven both at 2500', I was speaking to real power not theoretical. BTW both trucks have about the same 100,000 km, with the same compression to spec.
... and your actual experience behind the wheel?

Since when are published HP #'s theoretical? Do you think Toyota just pulls these #'s out of their ass based on how the truck feels ? This wasn't an attack on you personally Galt it was simply a stating of the facts.

My behind the wheel experience? Plenty of it. But it's not something I feel the need to prove to you.

[RufusTheDufus]

Originally Posted by lumpy70

I think your compression tester is off by at least 5 lbs. Why? Because diesel will not fire below 290 lbs.

I have a new Mightyvac digital compression gauge. I think my low reading might have something to do with the glow plug adapter I was using.

[Radd Cruisers]

Was the throttle plate held open during the process?

~John