Improved Cooling 345
- Thread starter cbmind
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Michael Mayben
IHPA Tech Moderator - Retired & No Longer Online
I've "heard" of this version of a 345 but never seen one or verified the existence!
The ic 392 was an "upgrade" response to a "hot spotting" condition between adjacent cylinders when using those motors in school bus and fully loaded medium duty trucks in vocational use. It had nothing to do with any engine cooling issue when used in light duty applications such as pickalls.
Those engines were most usually fitted with a governor system and run constantly with a full throttle against the governor such as when a school bus was fully loaded/overloaded.
It certainly does stand to reason that an ic version of the 345 was produced at some point since there would have been an economic advantage to the machining process on the engine build/transfer line.
And...the so-called "1980" model 345 motor used in the sii platform was a bastard! Ihc did away with the highly evolved engine cooling/thermostat bypass system that was dependent upon the use of the correct robertshaw-design "balanced flow" thermostat, a giant step backwards in my opinion. That was all about cost reduction at the time when ihc was undergoing financial meltdown.
Somewhere I have pics of one of these engines but I can't find 'em! The engine is in Jeff's stash at ihon. It appears to be a virgin pullout, he and I discussed this last October when I took the pics! Maybe he will look at that motor and see what the water tube routing looks like...maybe it's an ic also???
I really enjoy hearing about stuff like this and then chasing down the details! Glad you brought this up, let's get to the bottom of it! Please post some pics of the affected area of the motor when ya can!
The ic 392 was an "upgrade" response to a "hot spotting" condition between adjacent cylinders when using those motors in school bus and fully loaded medium duty trucks in vocational use. It had nothing to do with any engine cooling issue when used in light duty applications such as pickalls.
Those engines were most usually fitted with a governor system and run constantly with a full throttle against the governor such as when a school bus was fully loaded/overloaded.
It certainly does stand to reason that an ic version of the 345 was produced at some point since there would have been an economic advantage to the machining process on the engine build/transfer line.
And...the so-called "1980" model 345 motor used in the sii platform was a bastard! Ihc did away with the highly evolved engine cooling/thermostat bypass system that was dependent upon the use of the correct robertshaw-design "balanced flow" thermostat, a giant step backwards in my opinion. That was all about cost reduction at the time when ihc was undergoing financial meltdown.
Somewhere I have pics of one of these engines but I can't find 'em! The engine is in Jeff's stash at ihon. It appears to be a virgin pullout, he and I discussed this last October when I took the pics! Maybe he will look at that motor and see what the water tube routing looks like...maybe it's an ic also???
I really enjoy hearing about stuff like this and then chasing down the details! Glad you brought this up, let's get to the bottom of it! Please post some pics of the affected area of the motor when ya can!
Michael Mayben
IHPA Tech Moderator - Retired & No Longer Online
Found the pics...but they don't show the water pipe routing well enough to determine anything!
My concern at the time I took the pic was to document the elimination of the thermostat housing and how ihc performed the screwball workaround on the water pump housing. That is seen in the pic.
My concern at the time I took the pic was to document the elimination of the thermostat housing and how ihc performed the screwball workaround on the water pump housing. That is seen in the pic.
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Robert Kenney
Super Moderator
Just to elaborate on the ic 392 configuration.
The 392 was a special case where cooling is concerned as the outer diameter of the cylinder bores were siamesed (connected) together to allow the 4 1/8 bores and a ridged cylinder structure. This restricted coolant flow between the cylinders and created a pocket for steam bubbles to collect and hotspots. The 345 is not siamesed with its 3.875 bores, so I would think an ic configuration would not be needed.
GM had the same problem with the 400 inch sbc due to its siamesed bores. They added coolant holes in the head gaskets directly under the siamese connection due to steam being traped in the pocket between the barrels. The holes allowed the bubbles to escape and coolant to flow.
I May need to clarify my siamese statment. The 392 May have gone through a few revs where the cylinders were connected as I have heard that there May have been a 1/8 gap between cylinders.
The 392 was a special case where cooling is concerned as the outer diameter of the cylinder bores were siamesed (connected) together to allow the 4 1/8 bores and a ridged cylinder structure. This restricted coolant flow between the cylinders and created a pocket for steam bubbles to collect and hotspots. The 345 is not siamesed with its 3.875 bores, so I would think an ic configuration would not be needed.
GM had the same problem with the 400 inch sbc due to its siamesed bores. They added coolant holes in the head gaskets directly under the siamese connection due to steam being traped in the pocket between the barrels. The holes allowed the bubbles to escape and coolant to flow.
I May need to clarify my siamese statment. The 392 May have gone through a few revs where the cylinders were connected as I have heard that there May have been a 1/8 gap between cylinders.
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Carl Wiese
Member
Can you get a picture verifying where the water tubes are going? Also be aware that IH used the term "improved cooling" on the line setting tickets to denote a certain radiator and cooling package, that has nothing to do with the engine.
Carl Wiese
Member
Cool, I'd like to see them. I am kinda a skeptic, sorry, but I agree with Robert. There really is no reason to have an ic 345. IH would have had to rework both the block casting and the head castings on an engine they made for decades at a great expense. Then they would have had to reorganize their entire parts network and parts listings.
Re: Improved Cooling 345 Pictures
Had to use my darn phone, best I could do in the lighting. Couldn't find my cameras, back in fort worth I guess. Here you are
driver water tube lower connection
Driver water tube upper water pump connection
Pass water tube
Driver water tube full monty
The Scout, back on the road. John t floore's country store in helotes, tx. Rek concert. Quickie. Awesome parts Jeff, incredible ride, quality product. Thanks!
Had to use my darn phone, best I could do in the lighting. Couldn't find my cameras, back in fort worth I guess. Here you are
driver water tube lower connection
Driver water tube upper water pump connection
Pass water tube
Driver water tube full monty
The Scout, back on the road. John t floore's country store in helotes, tx. Rek concert. Quickie. Awesome parts Jeff, incredible ride, quality product. Thanks!
Block stamp is a bad picturee someone might be able to doctor it. Reads v345. Water tubes run from pump to block, not the heads.
Hope soon I'll get the tub adjusted where I can use the inner fenders, so I'll have to pull the front clip off again.when I do that, I'll be able to get better pictures.
Hope soon I'll get the tub adjusted where I can use the inner fenders, so I'll have to pull the front clip off again.when I do that, I'll be able to get better pictures.
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Tiny Yokum
Member
Michael Mayben
IHPA Tech Moderator - Retired & No Longer Online
John t. Floor's store??? Rek???? Helotes???? Tamales and 'que????? Lone star witha shiner chaser??????? "road goes on forever" is blastin' on the minidisc in my shop right now!!!!
Fuck man, scruu this IH shit, I'm on my way back to heaven in the hill kuntry!
I remember when george strait played for free at john t.'s out on the patio on Sunday afternoons and couldn't draw flies.
I know john t.'s is now a corporate entity and turned to shit as compared to the redneck rock days...but at least it's still there and not paved over like armadillo! And helotes looks like downtown sanan now.
Fuck man, scruu this IH shit, I'm on my way back to heaven in the hill kuntry!
I remember when george strait played for free at john t.'s out on the patio on Sunday afternoons and couldn't draw flies.
I know john t.'s is now a corporate entity and turned to shit as compared to the redneck rock days...but at least it's still there and not paved over like armadillo! And helotes looks like downtown sanan now.
Scoutboy74
Moderator
Take me with you mayben! I hear tell texas is fixin' ta see-seed from the union. Bein' that they're about the only state in this here kuntree what ain't got their collective haids stuck so far up there azzes financially, they could pull it off. Sounds purdee guud raht about now.
Hey guys thanks for the info.numbers on the passenger side boss say v345. Below that is:
a
344404
anyone have a clue what this is? Is it some sort of build date? Serial number perhaps? Think the build date plate is behind the valley pan on the block with two screwa holding it down. Trying to get it cleaned off to decipher it. Not much luck. Will post when available. Any idea when these engineswere offered?also, I'll probably go toih hell, but before in engine tech I listed this engine as a ic 392. Based upon the fact of the routing of the tubes as I could not at the time read the id on the boss because the inner fenders were installed. Currently they are not, hence the new id. Which of course leads to more questions... Different thread.
a
344404
anyone have a clue what this is? Is it some sort of build date? Serial number perhaps? Think the build date plate is behind the valley pan on the block with two screwa holding it down. Trying to get it cleaned off to decipher it. Not much luck. Will post when available. Any idea when these engineswere offered?also, I'll probably go toih hell, but before in engine tech I listed this engine as a ic 392. Based upon the fact of the routing of the tubes as I could not at the time read the id on the boss because the inner fenders were installed. Currently they are not, hence the new id. Which of course leads to more questions... Different thread.
Carl Wiese
Member
I have seen miss stamped blocks before, so that would be my guess. Frankly were never going to know the answer unless you tear into the engine and take some measurements.
Robert Kenney
Super Moderator
Exactly what I was going to post.
Even pop a freeze plug and see if the barrels are siamesed. No gap - 1/8 = 392, gap (.375 between) = 345
I've gota say that if the IHSTO guys haven't seen an ic 345 they probably don't exist.
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Michael Mayben
IHPA Tech Moderator - Retired & No Longer Online
The "a" is a common designator for engines that were "evolved" so to speak. That could denote many small changes made overall but nothing of any significance really. A simple cruise through the original parts lists for various engines in various platforms will show the differences as a part number change, but no information is supplied as to what the change is. That type info came down to the dealer base only as a service letter.
If there is an actual sheet metal or brass "tag" retained with screws or drive-rivets, then that would tell me the short block is most likely a "reman", either an IH "renew" part or some other vendor. That is standard practice on rebuilts/remans. An sv motor straight off the final assembly station would never have any add-on like that applied.
Block stampings can change though, maybe a mis-stamp during production, maybe it went through the "re-work" process which is an offline operation, we could bullshit about this for days. But all that matters is what it is now and how you service it regarding proper replacement parts.
Maybe at some point the right documentation for this subject will pop up, until then, it's beerthirty bs and one more urban myth.
Po's can expend an enormous amount of energy in screwin' stuff up! Including the old saw about swapping these heads around to increase horsepower! No doubt there are motors sittin' out there that are scrapped because someone swapped on one ic head onna non-ic motor and swapped around the water tubes...or put a 266 head onna 392 to "increase compression".
Good stuff gentlemen. Thanks. Doesn't matter a whole lot what it is, as long as it runs I suppose, just thought I might have been misled by the water tube location, as I had never heard of an ic 345 therefore I assumed it to be a 392. Maybe if Jeff gets a chance he can tear his apart, as mine is running (so far). Thanks y'all.
Robert Kenney
Super Moderator
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. I included a couple of pix for reference. Don't know how IH serialed these engines but probably sequentially as they rolled off of the build line. I suspect cb's engine has been re stamped to abide by CA emission shit and is really a 392. (no way to prove it). Note typical circular IH machine marks from tools in the plant at the time. These should be gone if ground and re stamped.
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. I included a couple of pix for reference. Don't know how IH serialed these engines but probably sequentially as they rolled off of the build line. I suspect cb's engine has been re stamped to abide by CA emission shit and is really a 392. (no way to prove it). Note typical circular IH machine marks from tools in the plant at the time. These should be gone if ground and re stamped.
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The "e" suffix engines where designated "emission" engines. The combustion chamber was redesigned, essentially going from quench to squish and flat top pistons. Robert k would see that as changing the surface to volume ratio. They came out in '67 for CA, and '68 for national smog rules. The emphasis was to reduce the need or eliminate the air injection systems or afterburners with future changes in carburetion and ignition at that time on the plann'in table.
The "a" suffix engines came out in '69 or '70 for the Scout, d-line, and metro models. Some folks refer to them as price break engines. They had a few less features than their industrial/fleet sisters.
The cranks where quenched and tempered as opposed to tocco hardened journals. Aluminum main bearings; the heads had no valve seat inserts, and thus were not to have exhaust valve rotators, to name a few. A bulletin in 1971 did show rotators were to be used from then on starting with the 304a.
All the sv engines except the ic392 had reverse flow cooling, the water pump delivered to the heads instead of the block, and that was considered high end. But as Robert k pointed out, siamesed cylinders made for a problem with that strategy. So the "ic" fix, you could say, was going to standard practice. I have seen a reference to cylinder scoring with the standard 392 in big truck usage, and I "believe" the fix was the "improved cooling". I have looked, but haven't found the paper for that, I have the number just ain't got the paper or copy.
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, or fan or both, and other options.
Hope that helps ya, and this info is off of IH documents, not beerthirty tall tales of internet.
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