3B and B engine, thermostat housing differences (1 Viewer)

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Joined
Oct 30, 2005
Threads
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Hi all,

Remember me?

1) broke down in Medford
2) left vehicle and went on vacation to mexico
3) returned in the new year to collect vehicle
4) discovered a shredded con rod bearing on #3 cylinder
5) purchased a used 3B engine (last weekend: Thanks ROB!)
6) installing used 3B engine (now)

I plan on posting a very informative thread about the differences between the B and the 3B engine when I have completed my swap. They are VERY very similar but there are some significant design improvements and differences.

Here's my question: I'm having difficulty figureing out the thermostat housing. There seems to be a much different routing of the main hose INLET to the thermostat. My old engine was a B from a BJ40, but my new engine is a 3B from a BJ70 or something (right Rob?). Does anybody out there in Cruiser-land have a photograph of their engine bay that they could send to sean.allan@powertechlabs.com ? Basically I'm trying to figure out if I have to move the entire thermostat housing from the B engine to the 3B engine.

Thanks guys!

Sean Allan
(No longer broken down in Medford)


. This is
 
The Rad cap is on the thermostat on later models, I like that location better.
 
superdude, stopped by seans place of work

Its funny, but he works less then 2 min from where I live so stopped by and he got some pictues of my 3B. BTW, are those trojon batteries? Look to be heavy duty.
 
Sean Allan said:
Here's my question: I'm having difficulty figureing out the thermostat housing. There seems to be a much different routing of the main hose INLET to the thermostat. Thanks guys! Sean Allan

Give Rob a call...if it's the Rob I am thinking of, he might know from having done a few B to 3B swaps.

As you discovered...The top hose for the rad is on the left for power steering equipted 3B trucks. Your new to you 3B t-stat housing point out to the left, where your B t-stat housing points to the right. When I renovated my BJ42 (1981 manual steering) I bought a new rad from Toyota (they only have the p/s versions now), and new matching t-stat housing so I was set in the future when I decided to add power steering. If you do not prep for that situation now, you will have to deal with it later. It may kill two birds with one stone for you.

To answer you main question, I don't know. Why not take both off and see...

Ohhh, even if you maintian the 7* series t-stat housing, maintain a rad cap on your radiator. It's a PITA to get all the air out the system with the one on the top of the t-stat housing...ala 7* series.

hth's

gb
 
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Loren (superdude) stopped by my place of work so I got a few pictures of his engine (with the darn powersteering pump). I also was able to determine that the second heater hose is for the rear heater of the BJ60, and I think I'm just going to end up capping this off. I have a rear heater in my BJ40 but is is tee-ed off the front heater a little bit differently.

The main question now is: Where does the coolant flow when the thermostat is closed and all the coolant is bypassing the radiator? On my B engine the thermostat housing has this funky 'U' shaped piece of hose that looks like a major weak point. On the 3B engine it looks like this is missing... is the bypass circuit INSIDE the coolant/water pump housing? (I'm guessing it is)

Sean.


Its funny, but he works less then 2 min from where I live so stopped by and he got some pictues of my 3B. BTW, are those trojon batteries? Look to be heavy duty.
 
SuperDuperCruizer said:
Here's a picture of my BJ42's engine compartment. They came with the 3B. I'm not sure if it's different from the 70-series 3B you have, but it might help you sort things out.

http://filebox.vt.edu/users/rhedderl/BJ42/Engine%20Compartment.jpg

COOL thanks for the picture, this is exactly what I was looking for. It looks like the thermostat housing you have is kinda like the one I would like to use, but I'm curious about a few details...

What is the red hose that goes just under the heater hose, and then drapes over your alternator and disapears under your air filter?

Would it be possible for you to snap a shot with more detail of the thermostat housing?

I just love cruiser owners. Everybody is so cool about showing off their engines and sharing their knowledge.

Thanks you guys,
Sean.
 
Greg wrong Rob if it was a 454 sure,Still in kindergarden with mosquto killer motor education,But I am trying.Donor was a 1984 BJ60.Lots of runing gear up here with swiss bodys.Glad to see Sean has started the transplant.
Cheers,Rob
 
Sure! I'll take some more pictures....

I will not be able to take any pictures till I'm back home. I should be able to get some more pictures posted by mid-week next week.
 
General 'B' and '3B' differences

Hey Rob thanks for the engine, the transplant is going very well. One little trip to Lordco, and I should be at the stage where I can lift the engine back into the engine bay.

General 'B' and '3B' differences:

1) Exhaust manifold bolts are larger diameter thread size
(M6 = B to M8 = 3B)

2) Oil cooler on passenger side of engine above oil filter housing, on 3B is not present on B. General oil filter housing differences, they do the same things, but the holes are in different places.

3) Glow plug heater in Air Intake manifold present on 3B, not present on B.

4) Thermostat housing inlet has two sensors on 3B and points towards driver side, coolant return is internal to water pump. Thermostat housing has one sensor on B and points towards passenger side, coolant return is thru a u-shaped hose.

5) Throttle body is rotated by 90° between the B and the 3B, on the B the cable pulls the throttle lever forward, on the 3B the cable pulls the throttle lever towards the passenger side.

6) Oil pressure shut-off sensor is in a different location. (hard to describe, I have pictures)

7) They both eat oil, air, diesel and beer (no wait, that last one was me.)

8) Alternators are very different, but I think this is more of a 12V (BJ60, 3B) to 24V (BJ40, B) difference. The vacuum pumps on the back of the alternators are also very different in tubing configuration and orientation.

9) Fan diameter is slightly larger on the 3B with larger mounting studs as well.

um... that's all I can think of right now, I hope this information can help some of you if you ever think of doing anything as stupid as me and you blow up your engine on your way down to mexico and decide to do a 3B heart transplant.

Cheers,
Sean.


I have quite a few pictures that I would like to post and I'm not sure what the best way to do this is. Should I get an upgraded membership? or can someone act as a 'host' for me and post pics for me?
 
Exactly what does the vacume pump on the back of the alternator do? Does it work with the oil?

I have not looked hard enough but there is a vacume pump for breaks ect?

Also, are there more advantages to having electric fans then mechanical fan? It would apear to me that the engine would have faster warm up times with electric fans.
 
haryv said:
Exactly what does the vacume pump on the back of the alternator do? Does it work with the oil?

I have not looked hard enough but there is a vacume pump for breaks ect?

Also, are there more advantages to having electric fans then mechanical fan? It would apear to me that the engine would have faster warm up times with electric fans.

The vacuum pump has three vanes which rotate oblong, and uses an oil film. There is a check valve on the intake pipe. It creates the vacuum for your brakes, and if you have assist clutch.

The clutch fan is viscous. There has been a fair bit of chat about the stock clutch fan. Try a search.

hth's

gb
 
1FE pig said:
Greg wrong Rob if it was a 454 sure,Still in kindergarden with mosquto killer motor education,But I am trying.Donor was a 1984 BJ60.Lots of runing gear up here with swiss bodys.Glad to see Sean has started the transplant. Cheers,Rob

Cool...Coming down to Cruiser Daze again?

Sean, glad you are resurrecting your 40...

gb
 
Greg_B said:
Cool...Coming down to Cruiser Daze again?


gb
I will be there, Costal Cruisers puts on a grand event.Hope to have one of the 45's ready for the run.Glad to see cruisers come back to life as well.Not roting away like I find up here.

Sean if you need any of the relay's or harness just let me know,I will ship to you.
Rob
 
Red Hose Question...

Okay, I checked to see more details about the red hose you asked about earlier... it's connected to the fitting that's been tapped into the water pump. On the other end of the hose is a filter mounted below the air box. A bit wierd since it doesn't appear to have a return line???? I'll take some pictures tomorrow when I can get my hands on my camara.
 
MORE Differences

10) Fan diameter is slightly larger on the 3B. Bolts for fan are also slightly larger

11) Exhaust manifold mounting studs are larger on the 3B M8-1.5(i think)
 
Are Water Pumps compatible?

Sean,

Since you have both a B and a 3B can you see whether the water pumps are interchangeable?.

My waterpump in B is making a funny noise and I have been adviced to use a 3B waterpump since B waterpumps are vitually unavailable.

Thanks

Mithila
 
I just replaced my thermostat housing both upper and lower and I have a different housing than what I had before. The only thing I can say is it must be from a newer variant of a 3B or maybe a 13BT. The main difference is it has more plugs in it to output water from so it will be very handy if I use a water cooled turbo!

It cost me $350 AUD btw from toyota, ouch but we all know toyota parts prices!
 
[Mithila wrote:]
>My waterpump in B is making a funny noise and I have
>been adviced to use a 3B waterpump since B waterpumps
>are vitually unavailable.

It's your lucky day, if you are interested I can take the water pump off my wrecked B engine and sell 'er to you! My B engine was wrecked due to a con-rod bearing failure, so the water pump should be fine. I'm not sure how to check if the two pumps are interchangeable without completely disassembling them both, and I don't want to do that since I got the 3B engine running and installed. (Thanks for the engine ROB she runs like a clock!)

Cheers,
Sean.
 

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