F series to H series engine (1 Viewer)

[DUKE775]

Hey everyone,
im considering swapping my f engine for a diesel and was curious as to what the pros and cons would be.
is it worth the time and money?
if i do make the swap what would be the best fit. i have a 1974 fj40
how many additional changes would i have to make/ additional parts to buy if the swap was made.
im not incredibly experienced but im a ch-47 mechanic and figure that the basic concepts transfer over.
thank you-duke775

 

[HJ45]

Hi Duke,

Below is the chassis dimensions for FJ and HJ, IMHO try and find a 2H as the H Engine has engine mounts which are located on the front of block and bellhousing as the H engine never had the rear transmission cross member meaning you would need to relocate both front chassis engine mounts and fabricate rear mounts.

Looks like the FJ has a rear transmission support, depending on what transmission you are using as the diesel and petrol boxes are different, eg input shafts., changing to a H box may lead you to then having to change your parking brake and drive shafts lengths front and rear, electrics for glow plugs and edic would also need to be installed.

The old H engines which i have had 3, would climb trees if you let them, being low torque and high compression, tailwinds are also preferred, but again IMHO go the 2H.

Hope this helped.

cheers
HJ45

 

[Vossie]

I agree with HJ45, go 2H if you can. My first 45 had a 2H fitted into an FJ45 body, and there were surprising few major alertarions. The mounts stayed on both the engine and gear box.
As for pros and cons
Pros
So much torque that when you floor it, the earth spins in the other direction.
Better fuel consumption. I got 8km to the liter and I drive only one way, lead foot.
If you get a 2H that doesn't need a fuel solinoid like I had, you don't even need a battery to run it. Great motors in emergency situations where you are far from no where.
Simple and easy to worK on.

Cons.
They not fast. The fastest I ever got my old 45 to was 115kmh with the windscreen flat, roof off and 60 series diffs. That's with a 4 speed though.
They are bullet proof engines and legendary for their reliability, but they really really don't like being over heated. So making sure that your cooling system is 100% solid at all times is critical. This is pretty much a gimme but I've been amazed how many H series engines here in Zimbabwe where I am get cooked because people don't check their coolant often enough.
Very loud and in a tractor sort of way. Sewing machine, the 2H is not.

All in all, I loved my 2H. Was a fantastic engine and I would really recommend it to anyone.

Hope this helps

Ross

 

[65swb45]

If gasoline was 25 cents a gallon, would you still do it?

The dirty little secret is these conversions never pay for themselves.

 

[78fj40mg]

I believe these little diesel engines are more about the torque, longevity, ease of maintenance, sound, etc. than the price of fuel, although MPG is an added bonus.

 

[DUKE775]

@65swb45 That is a god point but i dont plan on ever selling my 40 and i know that i will be putting more money into it then i would ever hope to get out of it. the same goes for a 1970 chevy c20 i have. sometimes its the joy of tinkering on things that really pays off.

@Vossie thankyou for the pro con list and for the 2h suggestion i just need to get my hands on one now.

@HJ45 awesome thankyou for the specs. as far as relocating and fabing the mounts do you have any advice for how difficult of a fab that is. ive done some small stuff ( making my own bucket seat mounts/frames ) but am mostly learning as i go.

 

[Vossie]

If gasoline was 25 cents a gallon, would you still do it?

The dirty little secret is these conversions never pay for themselves.

Unless where you live petrol sells for $1.30 a liter vs diesel at $1.02 a liter

 

[HJ45]

Welding/Oxy/Grinding/Drilling/Measuring all essential skills, you will need to determine what engine you may use to ensure correct engine height so bellhousing misses transmission hump and correct angle at transfer case when seated at gearbox cross member.

Making the mounts pretty straight forward. engine alignment on both axis the most important. i was able to use the original engine mount bolt holes, where you may need to re-drill.

As 65swb45 mentioned

The dirty little secret is these conversions never pay for themselves

is true if you need to get someone else to complete, otherwise its a great learning curve and true satisfaction of completing yourself.

Happy Engineering

cheers
HJ45

 

[Living in the Past]

Hi Duke,

Below is the chassis dimensions for FJ and HJ, IMHO try and find a 2H as the H Engine has engine mounts which are located on the front of block and bellhousing as the H engine never had the rear transmission cross member meaning you would need to relocate both front chassis engine mounts and fabricate rear mounts.

Looks like the FJ has a rear transmission support, depending on what transmission you are using as the diesel and petrol boxes are different, eg input shafts., changing to a H box may lead you to then having to change your parking brake and drive shafts lengths front and rear, electrics for glow plugs and edic would also need to be installed.

The old H engines which i have had 3, would climb trees if you let them, being low torque and high compression, tailwinds are also preferred, but again IMHO go the 2H.

Hope this helped.

cheers
HJ45

This frame charts just show the different in wheel base on the 8/80 and later frames. The spit transfer case and transmission crossmember started 8/80.

I do have a question are you saying the 2H used the same front engine mounts as the 2F? Since the transmission were the same in the F and H series on the engines crossmember should be the same on either. If the front engine mounts are in the same location on the 2H as the 2F that would make switching engines pretty straight forward at least as far as mounting the engine.

 

[roma042987]

the frame mounts on 2h and 2f trucks are in the same location on the 40 series

 

[FF LC FREAK]

Here's my $.02.

The H series engine was never available in the US market. Parts are getting harder to find, and typically you will have to have them imported from somewhere else (i.e. Canada or Australia). With that said, I had a 3B for awhile. It was a great engine and I enjoyed it immensely. However, there were times I had to wait on parts or fix the ones I had. It certainly isn't a deal breaker, but it is something to think about.

There are other diesels out there that are much more readily available here in the US, namely Mercedes (OM617 and others) and Cummins (4BT) - just don't let the purists hear that. If I was contemplating a swap, it would be with one of these, as parts are everywhere. Personally, I like the 4BT. A club member (boots4) has one in his 60, and it makes gobs of power. They are a bit louder than other diesels, but they are just as stout.

Here's one in a 40 from the Hardcore page - Diesel FJ40, 1974FJ

And boots4's epic thread - Family haulin'

Whichever way you go, make sure you document it well on here! And we all love pictures!

 

[DUKE775]

Here's my $.02.

The H series engine was never available in the US market. Parts are getting harder to find, and typically you will have to have them imported from somewhere else (i.e. Canada or Australia). With that said, I had a 3B for awhile. It was a great engine and I enjoyed it immensely. However, there were times I had to wait on parts or fix the ones I had. It certainly isn't a deal breaker, but it is something to think about.

There are other diesels out there that are much more readily available here in the US, namely Mercedes (OM617 and others) and Cummins (4BT) - just don't let the purists hear that. If I was contemplating a swap, it would be with one of these, as parts are everywhere. Personally, I like the 4BT. A club member (boots4) has one in his 60, and it makes gobs of power. They are a bit louder than other diesels, but they are just as stout.

Here's one in a 40 from the Hardcore page - Diesel FJ40, 1974FJ

And boots4's epic thread - Family haulin'

Whichever way you go, make sure you document it well on here! And we all love pictures!

yea i wasnt aware of the parts issues that came with the H series so thank you for the heads up. i would like to keep it "toyota" but in the end ill do whatever fits best.
as far as the cummings being louder, on a scale from a vw diesel to a lifted, cover your ears here i come, big A** pickup diesel about where do you think it would lie.
this rig will be used for some Nevada hunting and maybe a little California hunting too, so if it is going to be too noisy im going to have to pass on it.

 

[FF LC FREAK]

as far as the cummings being louder, on a scale from a vw diesel to a lifted, cover your ears here i come, big A** pickup diesel about where do you think it would lie.

Both links I posted above have video clips in them. Here's one of us on the Rubicon this past summer.

Rubicon 2015 Part 1

The white 60 has the twin turbo 4BT in it. It isn't that bad noise-wise, but definitely louder than the 3B in the red 40 in the same video clip. Putting a decent muffler on will always help. The big A** Dodge guys "rolling coal" can't seem to figure that out.

 

[HJ45]

Living in the Past

This frame charts just show the different in wheel base on the 8/80 and later frames. The spit transfer case and transmission crossmember started 8/80.

I do have a question are you saying the 2H used the same front engine mounts as the 2F? Since the transmission were the same in the F and H series on the engines crossmember should be the same on either. If the front engine mounts are in the same location on the 2H as the 2F that would make switching engines pretty straight forward at least as far as mounting the engine.

This is the manual i pulled the chassis chart from, looking at the chassis diagrams it looks to me as if the front engine mounts are in different location, i could be wrong, as roma042987 stated they re in the same location in the 40series, as for the earlier gearboxes and bellhousings now i am questioning myself. apologies for any incorrect info.

If H engines were not available in US market, here is photos of engine mounts for H engine in the 45 series in Australia

cheers
HJ45