swapping t19 for auto trans

adamsj

New member
I currently have a 392 driving a 727auto.
I have found a t19 from a 1980 diesel and was wondering if a flywheel from a 345 would fit the 392 application.
Any thoughts?
Thanks in advance for your input.:confused5:
 
It will bolt up. However, each flywheel was individually balanced for the engine it was mated with. That isn't to say it wouldn't "work," based on your definition of the word. Depending on how close the balance was, you might even end up with relatively little vibration.

The best route is to have it professionally re-balanced with the desired rotating assembly.
 
Thanks; sounds like I should get the extra flywheel if the seller has one. Appreciate your input kyle.
 
Are you thinking of snaking the flywheel from the diesel or ??? Gosh, would that even work? Even if it fit, the same potential balance issues kyle mentioned would exist. I think you'd be far better off taking your chances with the one from the 345.
 
Yeah, sorry I wasn't very clear about that.
He has the t19 from the diesel and also a flywheel and bellhousing from a 345.
If the "balance" is off what if any damage could be done by mating those two together?
Thanks,
jon
 
There are threads in the gas engine forum, maybe even a "sticky", that describe how IH engines were balanced at the factory. You should read them.

An "out of balance" engine vibrates when running - you can "feel" it. Vibration can shorten engine component life.

Mixing / matching flywheels (and crankshaft pulleys) on IH engines can affect the "complete balance" of the engine - resulting in vibration.

Since IH engines were balanced as a "whole" (engine assembled / flywheel / crankshaft pulley(s)), swapping pieces can be "problematic".

But, you could also be lucky and not affect the balance.
 
You need to verify that the input shaft length for the diesel sii is correct length/diameter/spline count for an sv engine application. All sv engine flywheels interchange as far as mechanical dimensions, but the balance factor for each is unique. The Nissan sd series diesel flywheels and bellhousings/bellhousing adapters are significantly different compared to sv mating parts.

The only proper way to swap flywheel/clutches/etc. Around from engine to engine is to have the flywheel and all parts attached "neutral" balanced. That way the mass of the donor rotating pieces will not affect actual engine balance in a negative manner.

And the donor flywheel assembly should be neutral balanced only after the flywheel itself has been resurfaced and verified as usable as far as thickness and friction surface condition.

Balancing the entire rotating unit means flywheel, flywheel>clutch cover bolts, clutch disc, and clutch cover as an assembly.

You will also need to remove any spacer that is present between the starter and the block on the autotrans-equipped engine. And you will not use the flex plate spacer and retainer/retainer bolts on the auto unit. You will need the bolts that retain the flywheel to the crankshaft from the donor and the threads of the bolts must be sealed before installing the flywheel to the crankshaft hub.

If the donor flywheel has significantly worn ring gear teeth, then it will need to be replaced before the balance work is done.
 
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