Gasket sets

[O.D. Fever]

Starting a rebuild and trying to get parts. Will a civillian 230 gasket set work? I have read that the head gaskets are differant. Is this true? Are the bearings the same? The rod bearings, 2,4,6 are different than 1,3,5??? Need to talk to a 230 engine Guroo. Have time , need help.. Joe

[randyscycle]

The head gasket is definitely different from the civilian to the military 230. I also think the valve cover gasket is different too.

Bearings I am not sure about, but I'd suspect someone will be along shortly to help you out on that with firsthand knowledge.

[brute4c]

Valve cover gaskets are the same but head gaskets are certainly not.
The 3 odd bearings are different from the 3 even ones.
Intake and exhaust manifold gaskets are the same...thermostat housing too...the manifolds interchange.
Timing cover and water pump gaskets do NOT interchange.
Oil pumps and gaskets and distributors do interchange.


Not sure what else you might want/need to know...just ask and I will help if I can!

[militarypotts]

Jon, just for the sake of asking, why are some gaskets interchangeable and some are not? Is their a major reason for this?

[brute4c]

Yes.
The civilian motor and the mil motor have big differences between them...basically most of the short block internal stuff interchanges and most of the head stuff internals interchanges...but the block and head themselves do not.
The block on the civvy engine does not have any motor mount bosses cast into it like the military one does. Instead, there is a steel plate that mounts between the timing cover on one side and the block and head on the other. This plate, at its lower outside corners has "ears" that stick out and the motor mounts come of of those to the frame.

Don't ask me why...

Anyway, the plate, at the timing cover/head point, is wider than the head to the drivers side, by about 2 inches or so. This overhang means that the timing cover is a different size and also the water pump is a different bolt pattern...with one of the 2 styles, mil or civvy, having an extra bolt compared to the other and the hose locations rotated a bit...though the 2 pumps at a glance look very similar, they certainly are not.

Because the civvy engine uses the plate between the block/head and the timing cover, the plate makes the seal between the 2 sections. The sides of the head as they run forward to the timing cover are straight and so are the sides of the block. In the mil application though, the timing cover at the block/head junction is wider than the head is when the sides are straight...therefore, the head gasket has triangles that cover the extra opening of the timing cover and the block and head are triangular on the front corners as well. If you look at figure 3-50 in the -34 maintenance manual, you will see what it looks like there with the head off...

So the mil engine is widened at the front a little to fit its timing cover and seal...the civvy engine isnt because it seals to the plate between the timing cover and the block/head.

This precludes the use of the block or the head or the head gasket from one to work on the other...though it may be possible to trim the extra triangles from the mil one to then allow it to work on the civvy motor...this is NOT confirmed though that I know of.

The timing covers and waterpumps do not interchange either...obviously.

Some of the less obvious differences are:

Mil engine has a "water excluder seal" behind the timing cover for fording...makes the crank a little different as well as the fact that the pilot bushings are different diameters.

The 2 piece crank pulley is not on the civvy motor.

Civvy waterpumps have a bolt on pulley with 1 groove...light steel...not the 4 groove very heavy pressed on cast iron one the mil motors have.




I think that covers the big stuff...there are minor things that differ...like the all metal oil line to the back of the head on civvy trucks versus the rubber one on the mil trucks and the intakes on civvy trucks dont have the water temp sender mounted on them...forget where it is but thinking the side of the head...they just have the port for the small radiator hose there...though it is easy to adapt a tee fitting into the single existing hole on the civvy manifold and put both the temp sender and the hose connection on...works fine and even the wire for the temp sensor is plenty long. These kind of things are really easy to overcome...not like the block/head/timing cover/engine mount plate deal.

Again...dont ask me why...the mil mounts are in a much better place in my book and it seems to me the way it should have been designed from the start...

[randyscycle]

Don't ask me why...

I have a theory that I may have advanced here before, but if not, please humor me.......

My opinion is that the 230 Tornado for the Military contract was a re-invention of the wheel so to speak. I know that the contract was initially proposed and even possibly begun while the Tornado was still in production. However, as is the case most times, the handwriting was on the wall and the Tornado was on the way out. OHC engines were not to be......yet. Too complex and too costly to produce and maintain. Add to this the fact that most likely fortunes were beginning to slide for Kaiser, and things weren't looking good.

Now, throw a military contract into the mix. The chance to save things and have a guaranteed customer. Now, if only they had an engine to fill the specs of a new frame, and hybrid body parts. I know! Let's drag an old design out and re-hash it a bit! Sounds good!, Let's go for it!

Maybe not in those exact words, but I believe that is what happened. There really wasn't any other viable engine out there to choose from from Kaiser's inventory, and making it slightly different was probably a necessity, but also a military requirement to keep the public from pilfering parts or giving this truck easy interchangeability with anything currently available.

Of course there is also the possibility that some guy in Toledo thought the best thing since sliced bread was the Tornado and decided to tweak it just enough to keep it in production with current tooling, and use it over again.

Just some thoughts, anyway.

[brute4c]

The frame, as far as where the motor is, is the same inside width and all as the J ruck frame...the 230 could have been mounted the same way in both civvy and mil form in the same rails...in fact, we have an old member who took out the mil motor when it blew and cut the frame mount of a civvy frame, welded it in and dropped in the civvy motor because he had one and didnt have a mil one...no problem once the old horns were off and the new ones on...

The body parts interchange too, if you take them as a set...so not sure on that part.

The original civvy engine did have oiling issues and some other problems related to longevity that, in the documentation I have seen, are referred to simply as teething problems that were ironed out...I wonder if there was an issue with the motors torque the made the motor mount change happen...something messing with clutches over time or something maybe.

Anyway, it seems like a lot of work to change mounts when the frame rail is the same, as far as this is concerned, and then add in all the expense of retooling the block and head...and some subcomponents WHILE still trying to keep the price to a bare minimum to get the mil contract...unless there was something that really needed to be fixed...

[BlessedM715]

There is a great article in Vintage Truck magazine this month on the development of the Tornado Engine.

[O.D. Fever]

My major concern at the moment is the short block. Is the civy and military main and rod bearings the same? Are the rods the same? I read the mil crank is forged steel and the civy is cast iron. I can see mine is steel. Also what is the differance in the 1,3,5 vs 2,4,6 rod bearings? oil hole?

[brute4c]

I dont remember the difference between the odds and evens, but it is there.

The cranks were all forged...mil and civilian...I have torn apart both.

The rods, rod bearings and pistons are the same...well...there are civvy 7.5:1 and 8.5 to one versions...mil only used the 7.5