My HJ61 Rejuvenation

[Fifty Hertz]

Next job was getting the front oil seal replaced. This was pretty easy with a decent puller. It took me all of an hour, including polishing up the sealing surface with some 600-grit paper.

The old seal was pretty much stuffed and was definitely the source of the front end oil weep.

New seal ready to go in...

Naturally I don't rely on torque alone for anything this critical. A liberal dose of Loctite 262 was applied to ensure that the pulley won't come off until I (really really really) want it to.

 

[Fifty Hertz]

Apart from a few final jobs I'm ready to start the front bodywork reassembly. Before I did this I wanted to give the A-pillars a quick treatment with some KBS, as I don't plan on returning to this area of the car ever. I didn't go overboard with the seam sealer, only doing around the top with the water can get in. The rest of the seams were already nicely sealed with paint and/or downwards facing so they don't present a risk. To be fair there was no rust in here anyway after 29 years so it was really just my underlying fussiness making me do this!

I overlooked doing the scuttle drains so just ended up giving them a couple of coats of cold-gal as I assembled.

 

[Fifty Hertz]

Now for some panels

 

[Fifty Hertz]

So far it's all fitting together well.

 

[Fifty Hertz]

I didn't have a helper today so I did the few last jobs on the engine.

New bearings for the power steering idler pulley:

New thermostat fitted:

New alternator idler pulley:

New viscous fan coupling:

Somewhere along the way I also fitted the new V-belts. Also these arrived today and will go in tomorrow:

I was planning to reuse the old radiator as I had it rebuilt a few years ago and it wasn't leaking. But I did a quick leak test on it yesterday and it's now weeping around a few of the tubes where they join the bottom tank. I guess some of the sludge was plugging the pinholes and now that it's gone, the leaks are showing. I called up the local Natrad agent at 8 this morning and they had this there waiting for me by 4pm. It's an Australian-made OEM-style copper/brass unit. Appears to be very good quality and the price was right!

 

[Fifty Hertz]

More progress today. I finally got around to making the lower support brace for the turbo. Used some 30x5 flat bar:

Fits in nicely:

That allowed me to fit LH inner guard and I then got the radiator fitted too.

I'm pretty happy with how it's coming together. If I get a good run tomorrow I should be able to fire up the engine and move the rig around to the spray booth!

 

[VX 12HT]

nice work mate certainly given the old girl a refresh....

 

[Fifty Hertz]

nice work mate certainly given the old girl a refresh....

Yeah it's getting all the essentials done and I'm not letting myself go overboard. Must admit that I would've liked to pull the engine and give it a freshen up (and some paint...). But it's only done 250k so the engine's still in great shape. It sounds sweet and uses no oil. So I've left it alone. The diffs were rebuilt when the air lockers went in and the H55F works fine.

Back into it today. Hopefully I'll have a sweet 12HT soundtrack for my evening beer

 

[Fifty Hertz]

LH fender on, battery trays in, vacuum system reinstalled, engine wiring done, nearly teady to fire up...

 

[Fifty Hertz]

The mighty 12H-T lives again

 

[Fifty Hertz]

It moves! Still a long way to go but it feels good to be able to move it around again

 

[dmjay]

Nice work mate.

 

[roma042987]

sounds sweet!

 

[Fifty Hertz]

So I've been preparing to take the 60 for painting on Monday before I head back to work for another month. I'd noticed a slow drop of coolant from around the turbo area and suspected that the coolant feed to the turbo was the culprit. By removing the cross-pipes I managed to fit better hose clamps onto the small hose that makes the connection to the front of the engine. Was a bit of a PITA but did it ok. Upon startup again the coolant leak is worse than ever.

Upon closer inspection I can now see that the coolant is dripping down from the manifold heat shield... which can only be one thing: the head gasket. Right? I can't see any other source of coolant from up high on the exhaust side. I guess is could be a frost plug that's sprung a leak - but either way it's the same outcome. Have a look at this crappy video (best I could manage with my phone in a very tight spot).

I'm pretty disappointed. It has never leaked before or used coolant internally. Maybe sitting idle for 8 months then flushing and running it again has disturbed pan incipient fault and pushed it to failure. Either way I guess the head has to come off now. Which means I'll abandon my idea of doing the valve stem seals in-situ and just suck it up and do a full head-off rebuild.

Now I'm in a bit of a quandary. Over the last few days I'd pretty much decided to get a shop to paint the 60 for me. I need to get this thing finished and onto the interior fit-out. The plan was to drop it at the painter on Monday and leave it with them for the 4 weeks I'm away, so it'll be all done when I come back. Now I'm thinking I have to hold off, as a head removal/rebuild/refit will definitely be easier without the car being any further assembled. In fact it seems like it would be a whole lot easier with the fenders and inner guards removed again.

Has anyone done the head removal/refit and have an opinion on this? Push ahead with the bodywork and come back to address the head later? Or hold off and get the head sorted first? Time for some ih8mud archive searching!

 

[HoJo 61]

Boo, bummer.

Are you 101% sure it is not the turbo water feed line that could spray water on heat shield?
If you answer yes, then there is only one option left which is sadly the head gasket.

You probably know what line we are talking (unconnected line under exh.man.) about but here is a picture nonetheless.

 

[Fifty Hertz]

Boo, bummer.

Are you 101% sure it is not the turbo water feed line that could spray water on heat shield?
If you answer yes, then there is only one option left which is sadly the head gasket.

You probably know what line we are talking (unconnected line under exh.man.) about but here is a picture nonetheless.

Yes mate that's precisely the hose that I checked this afternoon. I had put the hose back on with the original spring-clips (like in the upper left of your photo) so I thought these may be leaking. I removed them and put new extended tang (aka "mini EFI" or "lined") hose clamps and there's no way it's leaking from that hose. It's definitely coming from somewhere above the heat shield. Actually I don't think there are welsh plugs on that side of the engine so it could only be the head gasket.

I only have 2 more free days at home then I'm heading back to work in Mongolia on Monday night, so I've kinda run out of time to stuff around with it now. The other half will go spare if I spend any more time in the workshop this break! I've been pretty much non-stop at it.

I'm kinda thinking of taking it to a workshop on Monday and leaving it with them to remove, have the head rebuilt then reinstall it and then organise it to be taken to the painters. That way it could possibly be finished and ready for reassembly in 4 weeks time when I'm back. Hmmmmm decisions!

What's been happening with your rig mate? Minimal spanner time and some decent use I hope!

 

[HoJo 61]

What if you remove the heat shield, could you see the leak any better? And yep, there is no welsh plugs on the exhaust side.

Ah nothing major, upgraded to a Toyota 7M-GTE turbo which has slightly bigger compressor wheel.

 

[Fifty Hertz]

Yeah I'll try and get a bit more spanner time tomorrow and see what I can see. I'm pretty much resigned to taking the head off though. It's probably still on the original gasket which would make it 29 years old. As much as it's annoying, it's better to have it fail here in the workshop than out in the desert hundreds of kilometres from civilisation.

What's the 7M-GTE from originally? A Supra or something? Have you had a chance to run it yet?

 

[HoJo 61]

Sounds like a plan! What could be worse than blowing a head gasket in middle of nowhere...
If i recall, your engine had only 250k on it, right? That is pretty low actually but considering it's nearly 30 years old a refresh would be more than a better idea nonetheless, especially if you are going to drive long road trips.

BTW, do you remember what size the crankshaft nut was? 46mm i assume? I have valve adjustment and belt change on my To-Do list.

Yup, Supra engine. I did the upgrade about a year ago and have no regrets. With a little fuel adjust and 3" exhaust the HJ feels like a whole different vehicle, pulls WAYYY better than with stock turbo.

 

[Fifty Hertz]

Hello Finland! Yes the crankshaft nut is 46mm. I had to buy a socket and 3/4" breaker bar especially. You will definitely need to remove the radiator to get access. You may also need to remove the entire front panel assembly to deploy a decent 3-point puller. The puller I used was a pretty hefty one with 150mm span and looking back st my photos I think it would've been difficult or impossible with the front panel in place.

The other thing to consider is how you will lock the crankshaft to allow the nutto be loosened and tightened. I put the box in 5th gear and placed a tyre iron through the front UJ of the prop shaft so it was braced against the body. Obviously you still get some rebound due to the springs in the clutch. It came off ok (with an extra 1m length of steel pipe over the breaker bar) and I reinstalled it as tight as possible using some Loctite.

If you're just wanting to rotate the crank to do the valves and roll the belts on I guess you're not removing the pulley. No need to really unless you plan to replace the front oil seal like I did.

General question for anyone. Given a seemingly good 12H-T with 250k on it, what else should I consider doing in addition to a head rebuild? Obviously I don't plan to remove the whole engine at this stage.