Found a strange one today

Found a TD18 with a 671 Detroit engine today! Was this a common engine swap?

I don't think it as all that common as the Detroits were a lot higher HP than the IH diesel that I believe was only about 100 belt HP. IH had problems with tranny's and rear ends and I would think the added HP would be very detrimental.

That being said, at one time, Galion road graders offered a choice of IH engines or a Detroit. The exact models etc I have no idea but that would indicate there was some interchangeability, how much I do not know.

I think the 671 was about 200 hP and up. My experiences with TD-18's that it would last about 20 hours with that much power!!!

Just opinions above as I have never seen a TD-18 with a Detroit.

Hi, Bursitis.

I don't think that would be a very good swap - - - unless the 'Jimmy' was limited to about 1/2 its normal revs or maybe even less as the original TD18 engines were not very high revving. Otherwise, that thing would do about 12 miles per hours flat out.

That said though, some of the TD14s came out with a different transmission that gave them a top speed of about 10 MPH.

Also, I agree with D4Jim that it would tear the .fundamental orifice' out of a TD18 unless it was SEVERELY de-rated due to the much higher HP potential of the 'Jimmy' - - - could be 2 1/2 to 3 times more.

Just my 0.02.

Thats what i was thinking. The only comparison would be the allis chalmers hd 14 or 15. Those used a 671 at 1500 rpm i think so yes derated. It is setting but supposed to be operational. I'll try to get some pics

Pics

IH crawlers are a mixed bag. They were cheaper than a Cat. And they could act like it was made of crystal, bump it and it is broken. But some operators got a lot of work done with them none the less.

I have a friend with a lot of them, because they are CHEAP. And he likes to wrench, and figures things out. So to paraphrase my friend, square cut splines will never last like Cat's tapered splines, they would cheap out on bearing and put sideloads on ball bearing rather than use tapered roller bearing. As well as the engine that demands being treated with the utmost care, or it will crack a head if you blink wrong.

My uncle ran several AC HD 14's. He had a story that fits here. They were loading shale in carryall scrapers or cans as the slang term in the day. How much equipment was on the job I don't know. All were farmers with bigger crawlers out making an extra buck. He had HD 14 and another was running an IH TD 18. My uncle was loading much easier without a push Cat as was the guy with the TD 18. For what ever reason my uncle had unhooked his can. So the next morning when he got to the job the TD 18 guy was hooked to his can. With the explanation yours seems to load easier than mine. We can get more done if I can load easier. I was to young to get to know the old scrapers. But my uncles was a bit wider than the other, so it loaded harder.

Besides the AC having more HP it could of been my uncle was better operator. The other fellow was very generous with his time as to farm organizations and community things, so did not spend the time to become a smooth operator. But none the less a 671 DD is not way more HP than IH hoped there TD would handle. Would think the 1 out of 10 or maybe 20 operators that is thinking could get along well with that engine in a TD 18. But agree the average hired operator could have broken by noon.

Thanks Ray and others. I have never seen a 671 in a td18 before this one so i don't know if this was common or not. I was told that this tractor runs and operates as it should but also see that the paint still on the manifold is interesting. I might get it anyway just for fun? I'll have to look at the 671 specs but i looked shallow at the allis tractors and compared to the ih and the hp wasn't all that different with the 1500 rpm in the 671.

From my experience with Detroits, a big part of defining the ratings is the size of the injectors. GM made a range of injector sizes for each of the 53 and 71 series (I don't know about the 92 and 149 series) and so with the same governed speed, one could get different power ratings. For example, with the 8V71 NA in my truck at 2100 with N65 injectors, it produced 280hp. Same engine where the only difference is exchanging the injectors for N75s, it produced an advertised 318hp. Of course, one could add boost and get another range of outputs with the various injector sizes. It's very easy to swap out injectors and change the power rating. So the engine in your tractor may have the smallest available injectors for a low hp rating. You can easily check what injectors you have by checking the stamp on the side of them.

yes there was something like 30 different combinations of heads, injectors turbo and superchargers to get a engine fine tuned to your application. and detroit diesel guaranteed it would be the most efficient engine you could buy. the factory would swap parts for free(cost of freight) till you had it running at its best for sales of new engines.

a family friend is a retired ships master and marine diesel engineer and was factory trained on detroits.

if it was running at 1500 revs it would have to be a special application engine as the 71 series in particular make best power and torque between 1800 and 2100 rpm over 2100 revs it drops off sharply. same with the c series cat engines 1200 to 1800 rpm with peak around 1500 revs.

Hi, Ray54 and Bursitis.

If my understanding is correct, the early TD18s were around 103 HP and the AC HD14 was the 'big dog' of its time at around 130 HP. That'z around a 25% jump in power, NOT inconsiderable at that time.

BOTH machines were known for final drive issues while the Cats of the time were known for NO final drive issues and not many other issues either. But, if the TD18s were giving Final drive issues at 103 HP, then even a 'mere' 27 HP jump could be DISASTROUS.

Also, and again if my understanding is correct. the 92, 110 and 149 series 'Jimmys' could all be specced differently just like their little 'brothers', with varied injectors, heads, blowers, etc., giving quite a wide range of outputs for each model - sorta a GM specialty. Even air intake, exhaust and cooling could make a difference. I think all of them could also be set up for either clockwise or anti-clockwise rotation and exhaust and intake on either side too - VERY versatile designs.

Just my 0.02.