Improved Cooling 345

[RobertC]

The heads had no valve seat inserts,

there is a difference between "improved" cooling and "increased" cooling. Improved usually refers to the 392. Increased usually refers to a cooling system package such as having a larger radiator

Hmmm, I thought all IH sv heads had stellite / "hardened" valve seats.

The "urban myth"(?) that I learned was that if the seats were not hardened (had inserts), this resulted in "early" valve seat "failure" using unleaded gas...

Since valve seat "failure" does not seem to be an issue from all that I have read on various IH bulletin boards, I assume that the IH heads have hardened inserts...

Of course, many (all?) people do not put that many miles on their IH...

I cannot remember when leaded gas "went away", but I have put 43,000 miles on my t/a (and the original 392) since jan 2006.

Yes, increased cooling refers to the "size" of the radiator.

I ordered my t/a with increased cooling (no a/c) -- basically, you get the radiator that is part of the a/c package... As near as I can tell.

The eaton modulated fan is a separate item (option) on the window sticker for my t/a.

 

[Carl Wiese]

hmmm, I thought all IH sv heads had stellite / "hardened" valve seats.

The "urban myth"(?) that I learned was that if the seats were not hardened (had inserts), this resulted in "early" valve seat "failure" using unleaded gas...

Since valve seat "failure" does not seem to be an issue from all that I have read on various IH bulletin boards, I assume that the IH heads have hardened inserts...

Of course, many (all?) people do not put that many miles on their IH...

I cannot remember when leaded gas "went away", but I have put 43,000 miles on my t/a (and the original 392) since jan 2006.

Yes, increased cooling refers to the "size" of the radiator.

I ordered my t/a with increased cooling (no a/c) -- basically, you get the radiator that is part of the a/c package... As near as I can tell.

The eaton modulated fan is a separate item (option) on the window sticker for my t/a.

This is correct.

If you read IH literature you will see that all IH engines came with hardened valve seat since the early to mid 50's. They market this because they sell to farmers who have access to a number of different kinds and quality of fuel. The hardened valve seats is not exclusive to the ic engine from my understanding.

 

[Michael Mayben]

I'm posting a few pages of the ct-404-l data book published by ihc in April of 1973. And I said "few pages", this is not the entire document and is intended to be used for educational purposes only.

At that point in time, I would consider the data in this document to be correct for that exact point in time. This is not to say that some specifications did not change in subsequent production variations, and revisions occurred in similar documents issued right up to the point that production of the gasoline engines ceased sometime in 1984.

And while most all "specs" for materials and data for the entire sv series engines was consistent across the board, the 304 stands out as being "different" in some respects. Most especially in the are of the cylinder head spec. The valve seats in those heads were "induction hardened" and not inserts. Some folks might consider "hardened valve seats" to be the same thing as "hard seat inserts"...but the industry does not consider that term to be interchangeable! So let's be real careful when we toss out the terms "all" or "none".

Does that mean you would never see a 304 (or 152) head with inserts? Hell no...it just means that at some point those heads May have been run through a machine shop or a reman operation!

Keep in mind, the "6-258" and "v-400" engines were amc production items, not built by ihc. They came to ihc fully assembled and ready to stab on the production line.

The urban myth regarding unleaded fuel and valve/valve seat recession/wear was a fact for some engines...produced by some manufacturers. But it was not an across the board issue for all engines in that era. There were tremendous differences in materials and design used by all manufacturers for each engine series and that greatly depended upon the intended use of that engine! Same for all industrial engines in that era...and the exact same issues are coming around again right now because of the forced use of e10 as a motor fuel in most all parts of the country. This is not cut and dry simple!

An example...a 383/413 chrysler engine from say...1970. The "passenger car" version we are most familiar with was the standard duty motor, a fairly lightweight block casting. The "truck" version weighed about 50lbs. Additional, due to increased block rigidity and somewhat thicker castings.

The marine/industrial block was approximately 115lbs. Greater in weight! Greatly increased block casting thickness and support, particularly in the are of the engine support bosses.

Ihc produced only one version of these engines..the heavy bitch! But...the "motor vehicle" engines came off a separate line from the same basic engines produced for ag and industrial applications. Even the blocks and major castings were separated out in the foundry process.

I'm working with a guy right now that has some 196 engines that were produced by ihc for a specific stationary irrigation/water pump application way back when. And these engines are significantly different in their external setup as compared to a 196 used inna Scout/Scout II, mainly in the area of the ignition and fuel system as they are governor engines designed to run at constant speed, 24/7/365. These are nos engines in crates from approximately 25 years ago, and are going into some 900a pickups that were originally equipped witha 152 motor. And of course, one of his issues is wanting to use the oem 152 intake manifolds on the 196 which has an intake manifold that is completely different than what was used inna Scout or Scout II!

 

[Michael Mayben]

Here are a few more pages from the ct-404-l. These summarize the cooling system packages available...again, this is data from 1973...and some of this did change in subsequent years right up to the point at which production was terminated for light duty vehicles.

And let me reinforce..."ic" (improved cooling) is a term and design used to differentiate the design change incorporated for the 392 engine series with a block serial number greater than "1013196". The term "increased cooling" denotes a production line assembly "package" of particular items used to provide greater engine cooling capacity for vocational or heavy duty vehicle applications.

 

[Greg R]

I cannot remember when leaded gas "went away",

I didn't go away all at once, it was phased out.
I remember when the rule went into effect in 1975 with a plan for reducing content over time, boy did we cry the blues.
Finally in 1996, the sale of leaded fuel was banned for road use motor vehicles. I remember that year because that was the same year manufacturing r-12 was banned in this country.

Like Mike said; and I got this from engine shops, machinists, and head rebuilders, valve seat wear depended a lot on heavy use such as how many hours of high load high rpm, "pull'in a grade" type service did the engine get. IH blocks had alloy iron which was tough to start with, add the induction hardening and a a suffix block would probably do as well in light or delivery service as it's non suffix sister. Tetraethyl lead really only showed lubricative effects at high exhaust temps, but keep in mind it's main purpose was anti-knock.

 

[RobertC]

Mike, thanks for posting the info...

Mike / greg, thanks for the info... Getting harder "trying to remember"

when I looked up the increased cooling on my t/a, I found an IH part number next to radiator asm on my LST...

When I first looked in my mt-131, I did not find the part number listed (for the "standard chassis" -- 1010. 1110, 1210).

I looked further this morning and I found the part number under the ms1210 / 1510 figure / listing... (manual trans radiator...)

 

[Robert Kenney]

After much investigation by mr. Mayben and I, I have formed a new view regarding the closeness of a 392 adjacent cylinder barrels. I measure a 345 at 440 and michael measures
.540 and a cylinder wall thickness of .250 nominal not accounting any core shift. If we add the normal production casting core shift, a .100 differance is normal. Michael also has a 196 which has the same cylinder size and spacing as a 392 which he kindly measures and he found the adjacent cylinder barrel spacing to be .300 and based on core shift May be as small as .200. This means that the 392 barrels are not siamesed in the true sence. So I was mistaken in that regard.

Another way to determine what engine came up during our conversation. The blocks have a IH part number cast into them that will be consistant with either a 345 or a 392. The 345 I posted numbers and pictures of earlier has a number on the passanger side of the block about the centerline of the crank that reads 151-023-r5. I would expect the 392 to have a part number also in about the same area. That should tell us once and for all what cb's engine is. If cb could find us the number we could look it up and see what its application is.

 

[cbmind]

after much investigation by mr. Mayben and I, I have formed a new view regarding the closeness of a 392 adjacent cylinder barrels. I measure a 345 at 440 and michael measures
.540 and a cylinder wall thickness of .250 nominal not accounting any core shift. If we add the normal production casting core shift, a .100 differance is normal. Michael also has a 196 which has the same cylinder size and spacing as a 392 which he kindly measures and he found the adjacent cylinder barrel spacing to be .300 and based on core shift May be as small as .200. This means that the 392 barrels are not siamesed in the true sence. So I was mistaken in that regard.

Another way to determine what engine came up during our conversation. The blocks have a IH part number cast into them that will be consistant with either a 345 or a 392. The 345 I posted numbers and pictures of earlier has a number on the passanger side of the block about the centerline of the crank that reads 151-023-r5. I would expect the 392 to have a part number also in about the same area. That should tell us once and for all what cb's engine is. If cb could find us the number we could look it up and see what its application is.

I can do that mr. Robert, thanks to all who have offered good info on this. I know I've learned quite a bit about this, and I'm sure someone one will find this just as useful down the road.
Chris.

 

[Michael Mayben]

Let's get some part numbers posted here so we know what we're looking for.

Looks like all variations of a 345 I can find (May not be every one known though!) used the same block p/n (or as ihc referred to it...the "crankcase"). The cast-in number from the foundry is the part number...151023r5, (not a "casting number" as some of you that play with chryfordrolets are familiar with). Easily seen on the passenger side of the block between the first and second core plug bosses at the end of the starter housing. That number also appears in the lifter chamber between two lifter bores. There May also be some 345 blocks that carry a p/n 151023r51...who knows what is "different" about those blocks, but I suspect it has to do with a change in the engine mounts as that number only shows to be used in Scout II with no production date cut.

The part number for the non-ic 392 block will be 151339r61. That would be 392 produced prior to the serialized cut-off previously posted and those blocks would be machined for both dog bone front mounts or the horseshoe front mount.

The ic 392 block would carry p/n 436782c91 if it was for a horseshoe or dog bone mount install (mid '72>'73 production). For m/y '74 vehicle production, the 392 engine was moved "back and down" and thus the engine supports also changed to the "side mount" position, but not exactly the same as the side mounts used in all sv-powered Scout II. The '74/'75 model ic 392 block would carry a p/n of 436782c92.

So...there are two ic 392 motor vehicle engines floating around out there, the engine mount setup is what defines. A stationary/industrial engine app May be yet again "different". I don't have detailed parts information for those.

While both versions of the 196 I-4 motor shared many components with the sv 392, there was never an "ic" 196 produced for a motor vehicle as there was no need for one. Those motors were not used in medium duty trucks and buses, though many were used in forklifts, tugs, etc.

 

[RobertC]

Fwiw

345 blocks / crankcases

there was a post on bp a while ago where someone was trying to identify a block -- stated that 151023r3 was on the block.

The mt-131 (72 - 73 full size) I have shows 151023r41 for the 345 block / crankcase. The numbers for a 392 match what michael posted above.

I would think any block with 151023rnn would be a 345.

Finding the "source" of all the different rnn numbers would be difficult -- I think.

There is a date code on the sv blocks at the rear "above" the bell housing.

If I can remember, I will check the number on the block of my 392 in my 73 t/a when I change the oil.

 

[cbmind]

Mine's listed as 151023 r5 passenger side of the block, half way the length of it, centerline of the crnk, cast in, not stamped.

 

[Michael Mayben]

mine's listed as 151023 r5 passenger side of the block, half way the length of it, centerline of the crnk, cast in, not stamped.

So the block is a 345 that has been po'd!

 

[RobertC]

It might be interesting to check the engine date code (casting date) on these engines (at least to me:d ).

Here is info I "gleaned" from the bp

n = 1968
p = 1969
r = 1970
s = 1971
t = 1972
w = 1973
x = 1974
y = 1975
z = 1976
a = 1977
b = 1978
c = 1979
d = 1980

here is a picture of the 392 in my 1973 t/a --- 4 = month; 6 = day

 

[cbmind]

so the block is a 345 that has been po'd!

Is that po'd or pos'd? Good to know guys thanks a bunch. Either way, engine is running strong, have an issue with the vac advance, but I'm sorting it out, removed smog equipment, going to have dizzy recurved. Runs like a champ with just mechanical advance. 41 degrees total timing(w/ vac hooked up) at 3k rpm, 10 at idle, 19 degrees mechanical at 3k rpm. Needs some adjustment I'd say. Thanks again, I'll check my tag (behind valley cover?) manana, finally got my new ac condensor installed. Have a hot (pun intended) date at the mechanics shop tomorrow to get the system charged, can't wait, 108 degrees yesterday.

 

[Robert Kenney]

Cb, you need 36-38deg of total timing at 3k w/o vacuum hooked up. The vacuum adv only adds timing at low load conditions so under hard acceleration it is not applicable to performance. Your performance concerns are not going away by a recurve. A thought that maybe you curb idle is high enough to bring in centrifual advance. Should be around 650-700 rpm. You should have around 26 deg of mechanical plus the 10 of base for 36 total.

 

[cbmind]

Alright, I'll check that, thanks. Didn't have time to get a reading on the mfg date tag before dark, try again tomorrow. Thanks y'all

 

[RobertC]

Changed oil this afternoon.

I did not find a part no / casting no on the pass side block (392) -- blocked by starter?

Did find one (did not scrap all the burnt oil off) that I am pretty sure it is on the edge of the head.

 

[Michael Mayben]

changed oil this afternoon.

I did not find a part no / casting no on the pass side block (392) -- blocked by starter?

Did find one (did not scrap all the burnt oil off) that I am pretty sure it is on the edge of the head.

The number you see cast into the head itself is the part number for the head only.

It would not be unusual to not find part numbers in positions we toss out here. There were many core plugs/molds for all these type parts. And they were undergoing repair and refurbishing by the pattern makers and tool and die dudes constantly! The portion of the mold pattern that contained the part number was swapped around and it's entirely likely that some castings have no numbers cast in! Some May have later been stamped with p/n data

I say this over and over...but this "car and truck" production system stuff was not as "precise" and documented as some would like to believe, especially 25>50 years ago! And that fact is a contributing factor to why the aftermarket parts lookup dbase is so scruued up regarding anything IH-related!

 

[Tim Potter]

you know I can't resist btdh so here we go.

Been working on a 345 for a sw club friend and noticed a similarity with cbmind's ic345 deal. Remember this is a known standard cooling system and known 345 out fitted as it came from the factory in 1980 in a Scout II because he bought it from the dealer back then.

The serial number posted earlier 344404 is only 8 engines away from the one on my stand which is 344412.

Just to keep the record straight the block Robert has did not originally come out of my Scout. It's the block donated to the project by IHSTO.

The original block serial number is 343426 with a build date of 6-22-c (1979) which matches closely with my scouts September 79 build date.

 

[sonic1313]

So, I am new to this forum. I have a 392 block with new pistons and rings. Trying to understand what has been said--I have a 392 e with a build of r (70). With this block, the guy gave me 345 heads off an x (74). The 392 is not an ic...so, is the block and heads compatible? If they are, they don't look like they match up. What do you guys think? Or is it stupid to use 345 heads? Thanks!!!!