New to me 3B

[nuclearbeef]

I'm in the same boat as the OP. About to install a 3b w/ unknown history.

Reading between the lines... There is no major jobs that should be done while the engine is still out?
Install as-is, run it for awhile. then assess what needs addressing?
All the work on the head can be easily accomplished without taking the engine back out, right?

JW

 

[mano002]

As an owner of a boosted 3B, and seeing a few in our club. I would definitely go get a Toyota MLS head gasket. I'm sure John and Radd can get you one. I have a friend that overheated and cracked the head on his 3B and is in the middle of a rebuild as well. I would make sure your head is good before adding boost if you already have it apart.

In my truck, my 3B has 284,000kms on it, The head has never been off in the last 10 years since I helped the PO do the drivetrain swap into an FJ60. I have the wastegate welded shut and just drive by the temp gauge. I do have an intercooler, so my EGTs don't get above 800F. I make 17PSI of boost with a couple extra turns of fuel. I'm not sure this set-up will last another 100,00kms but its shocking how much better it is to drive on the highway with an RTT on top and a total weight of 6300lbs.

Is the factory HG MLS? If not what brand and where would you recommend getting it from as well as the other engine gaskets if I'm going to go this deep into it.

 

[mano002]

Yes, that's what I did, and you can take the head out without removing the rest of the engine.

I'm in the same boat as the OP. About to install a 3b w/ unknown history.

Reading between the lines... There is no major jobs that should be done while the engine is still out?
Install as-is, run it for awhile. then assess what needs addressing?
All the work on the head can be easily accomplished without taking the engine back out, right?

JW

 

[Monty231]

Gerg beat me to it.... do the diaphragm when you're in the back of the pump sorting the shaft out. There's a gasket on the back (governror) housing for the pump too, replace that while you're at it.

The original head gaskets were all composite, but in the early 90s (or perhaps very late 80s) MLS started to become a thing with Toyota diesels and all of the ones past 1990 had MLS gaskets. They are superior if your head and block surfaces are machined correctly for them (ask your machinist - they have to be almost mirror smooth).

The broken studs are always a pain to remove, but there are always the few that come out easily. Hopefully you won't have much trouble with it.

~John

Thanks John, I sent you an email last night about getting a parts list together for a top end rebuild.

If the block does not need decked, I'm assuming the factory finish can be honest or polished to a satisfactory finish as well as use the copper spray.

Should I think about replacing anything else in the bottom end? Cam bearings, ect?

 

[gerg]

Decking the block alters your compression ratio which is a big deal on an already high compression engine. If you want to turbo in the future lowering compression would be more of a bennifit.

Having the head machined also has drawbacks. The precombustion cups are not designed to be flush with the head. They are designed to protrude ever so slightly to make sure they have no room at all for movement. I have had friends, one was a mechanic actually, who decked the head with precups in bringing them flush and the precup "hammered" the head and block destroying both. The 3B cast head is quite hard to warp. I advocate the copper spray to fill imperfections helping the MLS gasket seal, which it has a reputation of liquids leaks, and avoid the machining.

If you did the head gasket and precups and flipped it over and did the bottom bearings yould be in good shape for a long time. 3Bs need all the help they can get with oil pressure. Also good to do that injection pump diaphragm since it's crazy simple with the motor out of the truck. Doing it in the truck is daunting to say the least.

Cam bearings would be a good idea as they tend to loose huge chunks but keep on running but it's a killer for oil pressure.

 

[gerg]

I'm restoring a bj40 and that's all I'm doing to mine.

 

[Monty231]

Decking the block alters your compression ratio which is a big deal on an already high compression engine. If you want to turbo in the future lowering compression would be more of a bennifit.

Having the head machined also has drawbacks. The precombustion cups are not designed to be flush with the head. They are designed to protrude ever so slightly to make sure they have no room at all for movement. I have had friends, one was a mechanic actually, who decked the head with precups in bringing them flush and the precup "hammered" the head and block destroying both. The 3B cast head is quite hard to warp. I advocate the copper spray to fill imperfections helping the MLS gasket seal, which it has a reputation of liquids leaks, and avoid the machining.

If you did the head gasket and precups and flipped it over and did the bottom bearings yould be in good shape for a long time. 3Bs need all the help they can get with oil pressure. Also good to do that injection pump diaphragm since it's crazy simple with the motor out of the truck. Doing it in the truck is daunting to say the least.

Cam bearings would be a good idea as they tend to loose huge chunks but keep on running but it's a killer for oil pressure.

Excellent info! I was actually wondering how that worked with the precups and a milled head, but that makes complete sense.

I've been looking through the FSM just to get an idea of any gotchas, but this is why Mud is so great. Y'all's input definitely is making this less daunting.

Now I need some parts!

 

[FJBen]

Good luck

I'm going down that rabbit hole on "while it's out" on my 13BT. Mine is a little different in that I'm rebuilding, but there is a lot to do.
IP, injectors, head gasket, head work, water pump, thermostat, misc engine gaskets, cam inspection/bearings....on and on



I think having your pump and injectors cleaned/check wouldn't be a bad idea at all. I sent mine in and they cleaned the injectors but the pump had to be rebuilt. Mine had fuel sitting in mine for 4 years and it turned to sludge. I don't know why unless it was bio as I've had way older diesel fuel be ok.



My head was rebuilt and "smoothed" out. My block was also decked a little and then the counterbore recut for correct cylinder liner protrusion so everything is still correct.

I'm in Cam bearing discovery mode at the moment. Apparently there are quite a few different sizes available for the 13BT (boxes say they even fit 3b) thats dragging my build out. Thats really the last part of the build I need. Good luck!

 

[gerg]

Injectors aren't a bad idea but indirect injection motors are a lot more forgiving with spray pattern vs direct injection given the majority of the air fuel mixing is due to the swirl chamber. Also, 3B injection pumps almost never fail and even if one did I'd recomend sourcing a used one. Since they rarely fail there are an abundance of them kicking around. I just sold one for 150$ which is a fairly common price. Are they dirty inside? Most likely yes. Me, myself and I and many others have used diesel purge with great results. It's designed specifically for cleaning injection pumps and injectors. I always have a couple cans of this kicking around. its my go to for smoking engines.
g

 

[Monty231]

Injectors aren't a bad idea but indirect injection motors are a lot more forgiving with spray pattern vs direct injection given the majority of the air fuel mixing is due to the swirl chamber. Also, 3B injection pumps almost never fail and even if one did I'd recomend sourcing a used one. Since they rarely fail there are an abundance of them kicking around. I just sold one for 150$ which is a fairly common price. Are they dirty inside? Most likely yes. Me, myself and I and many others have used diesel purge with great results. It's designed specifically for cleaning injection pumps and injectors. I always have a couple cans of this kicking around. its my go to for smoking engines.
g

View attachment 1899693

You got another one sitting around you want to get rid of? Since this one is unknown and it needs to be opened up anyway maybe I should just swap it and have an extra for a rainy day.

 

[gerg]

Injection pump? No sorry but shoot crawlin cruiser a message, he has some I think. What makes you think it needs to be opened up? Replacing the diaphragm is really not technically opening the pump. The diaphragm sits in a separate chamber if you will from the cam and the injection elements. I'd have zero issues running a pump that has sat for a long time as long as it's lines were connected and formed a closed circuit. The only thing that could really kill them would be it it were open and water got in it.

 

[Monty231]

I guess my ignorance is showing by not understanding the inner workings of it. And, that is part of the mainly twofold reason for wanting a spare. 1) I'm a tinkerer and I like to understand how things work. 2) I like to have spares for my junk so I can keep it running or help the next guy out.

Being I've never really worked on a diesel before I appreciate everyone's comments and patience with my dumb questions. I've been learning a lot recently.

On another note, I have a few emails out for quotes on engine gasket kits, precups and bearings.

 

[gerg]

No problem. It was a sincere question, not a criticism. I thought it might have seen some serious neglect or something like that. Engine gasket kits make life alot easier. I still buy my headgaskets from Toyota even when the kit comes with one. Lots of good places to get bearings from. The precups I linked before I've used multiple times with no issues. Stainless is not as good as inconel for high heat properties and might only last 10 years instead of 20 but who knows. It's like buying a Kevlar composite timing belt vs a regular one where it literally cost 10 times as much. This is complicated by the fact that precups don't have an actual measurable life span. It's like guesswork. Timing belts can be estimated with milage but precups......you just go by feel.

 

[gerg]

I've never heard of a Kevlar timing belt, it's just the first thing that came to mind as an example.

 

[Monty231]

Interesting, I had no idea what precups were made out of, much less what made a quality one. I'm vaguely familiar with inconel, my buddy is a welder at the local aircraft maintenance facility and was telling me about a scrap piece he had turned into a fire pit.

So, are the ones linked inconel or stainless? I didn't see it stated in the ad. Or are OEM Toyota inconel and aftermarket are stainless? Im having some fustration with this as the few places I've had contact with haven't provided me with information about their kit and what is included or what it's made of (inconel or stainless, composite or MLS). I know if I buy Toyota it'll be great and I emailed Onur and he suggested Engines Australia would be more economical, however they give no info on their kits other than price. I did ask a few questions, and they were answered, but I'm sure I'm forgetting something. I feel like I'd be better off buying a cheap eBay gasket kit and supplementing it with a Toyota head gasket and other seals where needed. Then get the precups you linked and source bearings elsewhere. I tend to overthink the problem instead of just biting the bullet and getting on with the project.

 

[gerg]

Inconel pre cups come from Toyota if you can even find them. Be prepared to pay more for the pre cups from them than all the rest of the rebuild parts combined. Stainless ones I've used for years without issue are like 100$ For a set

 

[DEADSALT]

...so stainless pre cups are deemed reasonably acceptable
and something you have used in the past,
in lieu of higher priced hard to source OEM Iconel pre cups?

 

[gerg]

Yup. Used stainless cups in multiple trucks over the last 8 years. Just bought another set from that vendor to do the head on my bj40. I've taken heads off after several years and checked the cups and no cracking was evident. I wouldn't expect any in such a short time anyhow but it's good to know.

 

[Monty231]

Well, I finally got some parts in and started the tear down. There are some odd deposits on the #2 piston and all the cylinder liners have some corrosion at the top. What do y'all think?

 

[Monty231]

I got the head back from the machine shop with a clean bill of health. No cracks, flat as a board and valve guides looked great. Now, to get the rest of the engine together.