HZJ80 new H152 gearbox clutch and flywheel modification (1 Viewer)
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If it's the stock HZ motor I'd use the torque for that flywheel. Loctite on the other hand I can't say. I've only over had experience with flywheel bolts with loctite on German cars. I it changes torque values. If toyota didn't recommend it on the HZ I would just go with clean dry threads.
real time help on Hz flywheel bolt torque please.
Hi All we are talking about a 2007 HZ in a 76. one book says 94 Ft.LBS the other as below. 94 will almost kill me, and my tools, what gives please, i need to button this up today if possible.
forum.ih8mud.com
Quick Google search came up with this
Flywheel bolts should *never* be bare dry! If a threadlocker isn't used they should be lightly oiled. I don't use anti-sieze on them as (like head bolts, etc.) they are a 'critical component'.
From 1PZ, 1HZ, 1HD-T FSM.
Does not call for lube on bolts.
If the FSM doesn't call for lube, I wouldn't use it. Just make sure threads are clean. Torque in a few passes. Something like 80, 90, 94lb or similar
Google search shows a lot of debate over loctite or no loctite for flywheels.
94ft/lb torque is pretty high compared to many other flywheel bolt factory torque specs.
Argument for loctite is to stop bolts vibrating loose.
Toyota doesn't see loctite as necessary to stop the vibration from a rattly, clattery agricultural 1HZ diesel rattling bolts loose. I'd skip the loctite.
The specified torque setting for the flywheel bolts is to ensure the bolt is stretched sufficiently to maintain tension in the bolt to keep it from rattling loose.
Torque to the tension specified for the bolt. It's about the bolt, not the flywheel, or engine.
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- Thread starter
- #6
Thanks guys have a new problem now the flywheel from vdj79 has 14mm holes and bolts that came with it are 14mm 1.5 thread as apposed to original 12mm 1.25 thread. I am thinking of getting the bolts stepped down so that they are large enough to suit 14mm holes in fly wheel but step down to 12mm 1.5 thread for 1hz crank. I'm not an engineer but I would think this would be the strongest way without drilling the crank as I would say it would be very hard to do unless was pulling it out for machining.
DivByZero
SILVER Star
You might be better off stepping back up a level and telling everyone what you started with and what you're trying to achieve. Swapping a H152 into a HZJ80 is usually done by keeping your original HZJ80 flywheel and swapping the input shaft from a H150 into the H152. If this is what you're trying to achieve, I'd read some more on H152 swaps to see what's been done before. You don't need to reinvent the wheel, and I certainly wouldn't want to get too "creative" with how you attach a flywheel. That's a lot of mass under a lot of force, you don't want it to let go.
Agreed.
I would not attempt to remachine the larger bolts.
The difference in thread pitch and small difference in diameter will leave you with all sorts of stress risers on the rethreaded bolts.
There's not enough of a step down to be able to remove all the 14x1.5mm thread.
The oem bolts are also likely to be rolled threads, not cut threads. Big difference in strength.
I would not attempt to remachine the larger bolts.
The difference in thread pitch and small difference in diameter will leave you with all sorts of stress risers on the rethreaded bolts.
There's not enough of a step down to be able to remove all the 14x1.5mm thread.
The oem bolts are also likely to be rolled threads, not cut threads. Big difference in strength.
I would think the vdj79 flywheel will have a different mass.
It is made for a v8, not a inline 6 cylinder.
I think your best option will be find a flywheel for a 1HD-T, 1hd-ft, 1hdfte.
They'll bolt up, and are the same except for clutch friction surface, clutch dowel and bolt pattern.
Or, use your flywheel, have it reground, and find a 275mm clutch with 14 spline centre to suit.
I think hzj75 had a 275mm clutch with 14 spline centre. Or maybe fzj75
- Thread starter
- #10
Thanks everyone going to get a hdj80 flywheel as already have 300mm clutch that came with the h152 gearbox from a vdj79 I have adapted to suit my hzj80. Think I will order new bolts instead of reusing just to be safe. The 300mm clutch and pressure plate is like 3 or 4 kg heavier than my original 275mm that's what kind of scares me but I would assume that this extra weight would be normal as is a larger clutch and pressure plate same as the hdj80 would have?
I believe the dimensions will be the same for hdj80 clutch vs vdj79, but not 100% certain.
Diameter, spline count, spline diameter is all the same.
@AussieHJCruza might be able to help confirm?
Diameter, spline count, spline diameter is all the same.
@AussieHJCruza might be able to help confirm?
AussieHJCruza
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@mudgudgeon they're both 300mm diameter and 4 spline, VDJ is listed as 32mm thick and HDJ as 32.4mm but this could be a data entry thing, I'd say they're both the same thickness.
The thing I'm not certain on is the pressure plate bolt pattern etc, I haven't got a pair here to compare.
Have been discussing with @Indestructible 47 this afternoon and haven't found anything conclusive.
One interesting discovery, the NPC 1600 has a 325mm disc. That's not much help with this discussion though!
The thing I'm not certain on is the pressure plate bolt pattern etc, I haven't got a pair here to compare.
Have been discussing with @Indestructible 47 this afternoon and haven't found anything conclusive.
One interesting discovery, the NPC 1600 has a 325mm disc. That's not much help with this discussion though!
Yeah, I saw the .4mm difference too. I figure it's insignificant.
If it were, all the H152 conversions would have run into trouble.
Wonder if the 325mm clutch works with stock flywheel? Or requires mods
AussieHJCruza
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The NPC 1600 kit comes with a billet flywheel, don't think there'd be enough real estate on the standard flywheel to mount it.
- Thread starter
- #15
OK so ran into some issues with the clutch when I compared it to my 1hz clutch the the vdj79 version was a fair bit thicker as in the clutch would be closer to the fork when engaging. I think because the vdj79 has a longer bell housing and fork set up, travel may be different as well. Without doing any mesurments have decided to play it safe and opt for a standard hdj80 heavy duty NPC clutch, pedal feel should still be the same as the original and has more clamping force than OEM
