Difference between 3B from 70-series & BJ42? (1 Viewer)

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Apr 18, 2005
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Are there any differences between the 3B engine in a 70-series and a 1983 BJ42? Is the transfer case and gearbox the same(theyre both 5-speed)?
 
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gears are fine spline vs coarse
cams are different
crank is different
block internals are different
alum bell housing vs cast steel
not sure if the bosses are drilled for the support brackets of the aluminum bellhousing in the 42 block design

if you are asking will the 42 block fit into the 70, yes it will.


you just can not use one engine for parts for the other.

HTHs
 
the idler shaft will be bigger in the 70 series than the 42 series.
the bolt pattern for th edriveshafts are different.

once again the whole assembly will bolt in.

Greg or Sheldon or Bruce will be able to answer this next one. i "think" the shift tower is different between the 42 and the 70 series, the 42 is 3" futher ahead... i am not absolutley sure but from what i remember there is a difference.
cheers
 
Thanks for your quick reply Wayne!
The reason I am asking is that I am thinking of fitting an engine from a BJ75 into my BJ42 instead of having someone rebuild my present engine. But I am just not sure how much work is needed to swap the BJ75 engine in.
 
I thought the later 3B's were clocked different...

Or is it just the turbo variety that's mounted differently? I'm just going from memory, but isn't the engine mounted at a different angle... and wouldn't this mess up the mounts for the trans and location of the shifters? Someone, please correct me if I'm wrong.

SDC
 
Sthlm said:
Thanks for your quick reply Wayne!
The reason I am asking is that I am thinking of fitting an engine from a BJ75 into my BJ42 instead of having someone rebuild my present engine. But I am just not sure how much work is needed to swap the BJ75 engine in.
if you do a complete engine, tranny,t/case swap then it is a direct bolt in with the possibility of having to cut the tunnel cover hole back 3" from center and using the driveshafts stubs from the 75 series. of course you do have the 24V BJ42 elec to bolt onto the BJ75(unless it too is 24V)
if you do the elec swap don't forget the glow plug resister in the intake manifold.
 
They´re both european spec 24v vehicles so that won´t be a problem. Is the gearing in the gearbox and transfercase the same?
 
Sthlm said:
They´re both european spec 24v vehicles so that won´t be a problem. Is the gearing in the gearbox and transfercase the same?
since this is foreign models i will step back. my guesstimate is they will share the same gearing in the tranny,t/case but other parts of the world could have gotten different configurations.
cheers
 
Tonito said:
But most BJ7x have a 24V electric-system - I thought the 12V version is limited to the 1985's BJ7x!? greetingz

Did Europe get the 12V BJ70 in 1985 as well as Canada? At least you did not get the evil center tap system to run 12V headlights?

gb
 
crushers said:
gears are fine spline vs coarse

cams are different

crank is different

alum bell housing vs cast steel

the idler shaft will be bigger in the 70 series than the 42 series.

i "think" the shift tower is different between the 42 and the 70 series, the 42 is 3" futher ahead

HTHs

What gears do you mean are coarse and fine?

Ya...was it in the 1985 model year the cams went 5 bearing, from 3...or was that 1986?

EPC shows the bottom crank from 1980 is 14401-58010, which crosses up to 58020, which crosses up again to 21. all to 1988/08.

The boss's should be there, just not drilled out for the braces on the aluminum bellhousing. You can interchange them. A local fellow put a 1983 3B into a Cdn 70 series, and maintained the aluminum bellhousing.

If memory serves the idler increased in 1985/10, so anything before that is 34mm. All bets are off with foreign market as Wayne says. As a rule anything after 1985/10 will be 38mm, but something is telling me there is one application that used the 34mm for a while(I just can't remember what is was).

The shift tower is 3" different between the H55F 40 series and 60 series. I believe the tower between the 60 and 70 are the same.

I don't know what year Toyota went to a 3 bolt alternator support. The older 2 bolt sucks.

H55F will be the same, but all bets are off if the t-case lowrange gearset will have the same ratio. Actually, there is one change for the 1983 H55F. 1984 and up there was a vibration anti-rattle bushing, or some such thing that was changed for the gear shift lever. My 1983 H55F rattles like a banshi..:-(

hth's

gb
 
I am confused I have an 84 BJ42 which is the same as an 83 BJ42 and my 3B is slightly different than an 85 but the drivetrain seems to be the same, I have the belly mount for the 5 speed instead of the wings from the bell housing and the flanges are the same on my 42 as the 70. The only noticable difference looking at it is the ps pump is mounted on engine, and the oil filter is mounted upside down from the oil filter on the 3b in the 70 series (that is the indicator of changes to the engine inside?)

Michael
 
Greg_B said:
What gears do you mean are coarse and fine?

The boss's should be there, just not drilled out for the braces on the aluminum bellhousing. You can interchange them. A local fellow put a 1983 3B into a Cdn 70 series, and maintained the aluminum bellhousing.

gb

I am pretty sure the 42 (83/84) are the same tranny mount as 70 series)


Greg_B said:
If memory serves the idler increased in 1985/10, so anything before that is 34mm. All bets are off with foreign market as Wayne says. As a rule anything after 1985/10 will be 38mm, but something is telling me there is one application that used the 34mm for a while(I just can't remember what is was).
gb

Is that the t-case idler you are talking about and if so are you saying the rebuild kit for an 86/87 70 series would be different than and 85 70 series?

Greg_B said:
The shift tower is 3" different between the H55F 40 series and 60 series. I believe the tower between the 60 and 70 are the same.
gb

I just did a 60 series H55F and an 85 H55F and the shift towers were the same


Thanks,

Michael
 
Sthlm said:
Are there any differences between the 3B engine in a 70-series and a 1983 BJ42? My engine is consuming serious amounts of oil and I am thinking about buying a second hand engine for it. Is the transfer case and gearbox the same(theyre both 5-speed)?

Check to see if the 7* series is vacum shift or not. I do not know the dates for change in Europe. rick_d posted up some part numbers, in conjunction with Beanz, that would let you swtich to manual shift from vacum, without having to change the t-case.

hth's

gb
 
tlcruiserman said:
IIs that the t-case idler you are talking about and if so are you saying the rebuild kit for an 86/87 70 series would be different than and 85 70 series?Michael

Yes, the t-case idler. I am stretching my memory this early in the morning with no Java. Always a good idea to measure the idler when you are going to order a kit, just to make sure a PO did not change something out. I "Believe" it was 1985/10 the big swtich to 38mm happened...but hey, I thought the Cdn spec 86/87 BJ70 did not have a stock converter to run a 12V radio, so what do I know...

hth's

gb
 
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tlcruiserman said:
I am pretty sure the 42 (83/84) are the same tranny mount as 70 series)Michael

Damn...I need a coffee.

The aluminum bellhousing clocks the transmission slightly, so while the rubber transmission support bracket may look the same, if you look closely you will see the transmission is clocked differently (off the horizontal plane). Cast iron clocks the transmssion pretty much horizontal, while the aluminum moves one side up a little (I believe it is the right side).

hth's

gb
 
Greg_B said:
Damn...I need a coffee.

The aluminum bellhousing clocks the transmission slightly, so while the rubber transmission support bracket may look the same, if you look closely you will see the transmission is clocked differently (off the horizontal plane). Cast iron clocks the transmssion pretty much horizontal, while the aluminum moves one side up a little (I believe it is the right side).

hth's

gb


Hmm. Interesting, now the only reason I could see them doing that is to clear the hood on the 70 series maybe....well just a guess. but that is good to know because I was going to put the bellhousing from a 70 series in my 42 series so I can use the pickup for a tach from the 70 series. Maybe I will have to rethink it.

What about the spline count?? I thought all the H55f's were the same for the 3B regardless what they were in.

Cheers,

Michael
 
The 40 series H55f had a different shift tower to the 60/70 series. The clocking allowed the t-case outputs to be lower and made for a nearly straight driveshaft in a stock 70 series. This can be advantageous in a highly lifted rig though the diffence is slight (maybe 1") As Greg mentioned the tranny mount is different and there is no way to cross it over using factory parts. You'll have to shim the tranny mount if you want to use the aluminum ballhousing. I'd recomend using your cast iron bellhousing for simplicity sake even if you use both the engine and transmission for the 89. The fill plug is slightly different on the t-cases that came behind the aluminum bellhousing so if you use your case one with the '89 t-case you might have to jack up one side of your rig to get your t-case filled correctly. Probably not a big deal though.

The only difference I can think of that hasn't been discussed is that the '89 BJ75 engine likely will have a rotary injection pump and different exhaust. This will make for some work adapting the existing linkages, fuel lines and exhaust. The rotary pump may also require a return line to the tank.

Additionally, some alternators have external regulators and some are internal and the starters are clocked differently from 3B inline pumps compared to rotary and 13BT inline pumps.
 
tlcruiserman said:
I was going to put the bellhousing from a 70 series in my 42 series so I can use the pickup for a tach from the 70 series. Maybe I will have to rethink it.

I have a 60 series cast bellhousing with the tach boss that's headed for the bin if you need it.
 
Greg_B said:
What gears do you mean are coarse and fine?

gb
the timing gears in behind the "heart"..
 

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