Packrat, another thing to concider is the hi idle on your existing engine and the hi idle on the cat engine you are going to install, you may loose road speed if the cat doesn't rev as hard as your existing engine and you may need to up your diff ratio to compensate for this. regards

Good morning Holt2Ton,
Thanks, I realize that. Actually, if I do this, I'm starting from scratch. I've been looking for KW's since I sold my '85. I want to get an older one but I want it to end up with a Cat engine but something before the 3406. I've found several trucks but the right one just hasn't shown up. My intention is to mount my 1942 (I think) D13000 Gen set on the back for something to go to shows with. We will see; I know that talk is cheap. Wife has a hard time understanding all my brain eruptions.
Packrat

The high idle for a 1693 425 HP TA is 2375 RPMS & full load is 2100 RPMs with a .135 rack setting.All but the very early engines built they ran in about the 2300 RPM range but depends how it,s set up & varys slightly but the engine will stand the 2375 RPMs. Packrat if you need any setting up specs I have a book here with the settings in it.

"SJ" wrote:

Yes the 1693 was turbocharged & the higher HP ones were aftercooled & they were a 5.4" bore & 6 1/2" stroke which gave them 893 Cu.in. displacement. The 3406 was the same specs.There were various HP ratings but most were 325 HP turbo charged only & the high HP model with aftercooling too was 425 HP.I ran one on the dyno at work one time that I rebuilt & he had it set up a little & it put out 550 HP without any sweat & he wanted it left that way which I did. He hauled from coast to coast so going over the mountains out west he needed the extra HP he said. He drove it himself & took real good care of it & it had 880,000 miles on it when I majored it for a bearing that went out.I had done some in frame work on it over the years before the major overhaul.He was a local customer of ours but passed away at too young an age.Don,t know what ever became of his cab over KW. The 1693 was a dual overhead cam engine where the 3406 isn,t so they are totally two different engines the way they were made.

Hi SJ, been awhile since I've posted but here goes:

I have two engines, one is a 1693TA in a 1978 Mack, (RL-755L) that is factory equipt with "Brakesaver". It runs very strongly rated at 425hp. It is fresh with an out-of-frame overhaul but unaltered in factory settings/horsepower.

I also have a D343 engine from an Oshkosh P40 series airport crash truck that is factory rated at 425hp also. This rating is stamped into an aluminum tag affixed to the flywheel housing. These two engines look identical with the exception of the flywheel housings, as the D343 does not have "Brakesaver". What puzzles me is that the build sheet for the Oshkosh truck states the engine to be rated at 630hp and the serial number of this engine matches the line set ticket. The D343 engine mounted backwards in the chassis with the radiator located at the rear of the chassis. It, (radiator) is much too large to fit a conventional road truck. I did drive the crash truck before it exploded the transfer case, (literally) on the tarmac and it did run very well with locomotive smoke upon acceleration. I'm surprised one of these engines would run that much sustained horpower and give an acceptable service life.

The reason for this long winded history lesson gives way to just a couple simple questions I have concerning a Kenworth chassis that I have slated for this engine:

Will I need to "tame" this down a bit before installing into a W900A series Kenworth tractor originally equipt with an NTC-400 Cummins engine?

Would one have to keep a constant eye on the pyrometer during normal driving such as bobtail, or hauling an empty trailer?

The tractor will not be worked hard consistently, rather haul grain and such during harvest.

Thanks,

Rob

According to CAT, caterpillar engines with pony motors were installed in trucks in the early 1930's by truck owners. In the publication, Caterpillar Story (1984) it shows a really old Mack Truck with a CAT engine. You can see the starter rope for the pony looped over the windsheild support. No report on how they handled but it looks like a pretty low speed operation.

Rob, if that engine is set up for a high HP I,d have it set back to the 425 HP max. if I were you. The D343s had a big heavy rear bell housing on the engines used in equip. where the 1693 truck engine had an aluminum housing to cut down on weight etc.Also there were a few other small changes too so if you can I,d try and get the engine that came out of an OTR truck so it would be easier to install and set up.I can,t just remember if the real early 1693s had that big injection housing & governor on them like the early D343s had but try and find an engine with the smaller more compact housing on it.

We had some trucks with the 3306b engine in them.have heard that this also was a equipment engine also.Is this info correct?

Yes the 3306 was used in equip. besides a truck engine.Most all truck engines are also used as industrial or equip.power.

Thanks SJ

"SJ" wrote:

Rob, if that engine is set up for a high HP I,d have it set back to the 425 HP max. if I were you. The D343s had a big heavy rear bell housing on the engines used in equip. where the 1693 truck engine had an aluminum housing to cut down on weight etc.Also there were a few other small changes too so if you can I,d try and get the engine that came out of an OTR truck so it would be easier to install and set up.I can,t just remember if the real early 1693s had that big injection housing & governor on them like the early D343s had but try and find an engine with the smaller more compact housing on it.

Hi there, the D343 has an SAE #1 aluminum flywheel housing with a flat flywheel. It also has twice the number of bolt holes around the perimeter where the trans would bolt up. The injection pump/governor assembly looks just like the 1693TA in my truck. I believe this was referred to the "compact" pump. It looks like the 1693TA, only painted red with a different decal on the cam cover.
I've got photos of both engines on another computer and will make attempt to post a few tomorrow.

Thanks,

Rob

I only had one photo of the 1693TA in my Mack on this computer. It looks just as the D343 engine does with minor differences.

Rob