HJ45 Welsh Plugs - Please Help

[rich333]

Hi, I have got myself a 1977 HJ45 (Australian) - fuel tank under seat. I dont know a thing about fixing cars and got the old 40 so i could start to learn. The welsh plugs need replacing, so i guess this is my first little project.

I'm not sure exactly where to start and what exactly needs to be done in terms of being able to access the plugs? Do i need to take out the transmission?

Anyone had do this at all? Any help would be great.

 

[watrob]

Hi, a hj45 1977 may have h diesel or 2H diesel, if remember there is also a welsh plug at the back of the head on the 2H as well and because it is right up against the firewall you will not be able to get at it.

There will a couple others at hard to reach places as well, if it was me I would pull the motor out, not not worth missing any.

 

[Buckwheat]

If you have leaking freeze plugs or expansion plugs, as Welsh plugs are known up here, you have a corroded cooling system throughout, so I agree with the above - pull the engine. If the engine is a good runner, you should consider a cooling system flush to get as much scale out of the block as you can, before hoisting it up & replacing the plugs. Brass are available, so go with those for a little more longevity out of them. If the engine is crap, rebuild it. I can't think of a better way to get acquainted with the fixing of cars.

 

[Shane1981]

Not being landcruiser specific! I have known people that have cut holes in firewalls to replace welsh plugs so they didn't have to pull the motor out. Not sure why i told you that, it a pretty stupid idea for too many reasons to list but i thought it was a humurous addition to the topic.

 

[65swb45]

This is one of the few areas where I am RELIGIOUS about getting stock Toyota parts. After 22 years of wrenching on cruisers, I have seen too many AFTERMARKET freeze plugs fail to offer or stock anything else.

Best

Mark A.

 

[rich333]

thanks guys! i got the engine out, stated doing the plugs and the guy at my locla parts store gave me the wrong size plugs... is there a list of how many and what size plugs are required?

i'm havin a ball with it tho, and learning pretty quick....

also, any idea how to tell what model transmission i've got, seeing that i had to take it out i was thing of replacing all the seals etc (because oil leaks out the fill plug - i heard this was due to a broken seal between the trasfer and tranny)

 

[FJ40Jim]

Those engines use Welch plugs to seal the water jacket.

Welch Plug page <----- click me, I'm a linky

A Welsh plug would be a wad of tobacco for a guy w/ a funny accent, yes?

The transmission type is listed on the data plate on the firewall. It will be something like J30 or H41 or H55.

 

[Master jedi]

Hi guys im really needing some advice about welsh plugs in the 12ht block. Cant find any info on how many plugs are required to complete the block. I have replaced the one behind the waterpump housing 55mm o/d
I have also replaced 2 on the rear of the block which are also 55mm o/d.
Im not sure what the two plates underneath the manifold are called but there are 4 more inside those covers which are 35mm, on the otherside of the block in between the block and deisel pump is another plate but i am not qualified to remove the deisel pump to get to that plate and check if there are any welsh plugs in there..does anyone know if there are any welsh plugs under that plate??

 

[FJ40Jim]

Probably has no Welch plugs.
Something that new should be 100% cup plugs.

Dunno about exact quantity and sizes, but will all be metric, not half metric & half imperial like the old F series.

 

[Dagha Boy]

Hi Master jedi. Sounds like you have the motor out. If so, just knock them all out and measure them with a Vernier. I have just had an H engine done, the plugs looked perfect and I had decided not to have them done until I removed the cover on the side of the engine block which hides 4 (Ithink) of them. One was weeping through a microscopic hole but other wise looked perfect. Turns out they were all rusted to within a few microns from the inside. I did not rebuild the engine myself so cannot tell you how many and what size - three different sizes if I remember correctly.

Sorry on reread I see you found the hidden ones. There is nothing near the injector pump no need to dig in there.

I'll take a quick look tomorrow and let you know.

 

[Michael B]

@Master jedi look in the Diesel forum. Roma has a build thread there and he is almost completed a 12HT long block rebuild. I know he replaced all of the Welch plugs and I believe he named the sizes as well as his source.

 

[Master jedi]

Hi Master jedi. Sounds like you have the motor out. If so, just knock them all out and measure them with a Vernier. I have just had an H engine done, the plugs looked perfect and I had decided not to have them done until I removed the cover on the side of the engine block which hides 4 (Ithink) of them. One was weeping through a microscopic hole but other wise looked perfect. Turns out they were all rusted to within a few microns from the inside. I did not rebuild the engine myself so cannot tell you how many and what size - three different sizes if I remember correctly.

Sorry on reread I see you found the hidden ones. There is nothing near the injector pump no need to dig in there.

I'll take a quick look tomorrow and let you know.

 

[Master jedi]

Hi guys appreciate the replies, ill be stoked if your right dagha boy..fingers crossed.
I do have the motor out. my head has been machined and fully serviced. 6 out of the 12 plugs on the head had holes.
So im replacing the ones on the block..
I just dont want to put the motor all together and install it to then realise i have missed a plug because so far out of the 7 plugs i have replaced in the block 4 of them have had holes, my only worry now is are there any welsh plugs behind the deisel pump?
Ill wait for the reply cheers.

 

[Master jedi]

Sorry welsh plug sizes are 50mm,30mm,35mm..

 

[Dagha Boy]

I had a look at the H Engine yesterday but with all the stuff hanging on it I can't see well enough to give you a dependable answer, but I can confirm nothing behind the Diesel pump.

 

[desak]

Sorry welsh plug sizes are 50mm,30mm,35mm..

Just came across this post. I have an early 80 HJ45 that also has the h diesel. I am about to start replacing some failing plugs. Did you ever find a "kit" with all the necessary plugs? It seems I can find kits for everything but the H. If not, do you remember which ones you ended up needing.