Working on a story about Kenny Walker's (Both II and III) D315 engine from their D4 for Diesel World. They had it running on a stand at last year's Threshers Reunion at Wauseon, Ohio, and I shot it there.

Researching the engine in my own materials leaves me with a few informational gaps. One of them is the production years for it. I know it debuted for 1947 and I see it in catalogs as late as 1960. I DON'T see it in the 1965 Diesel and Gas Engine Catalog. My materials indicate the D4 underwent some major revisions after 1959 and the D4C wasn't really the same unit as before and had a different engine (which, I have not discovered yet). So did that pretty much end the D315? Many thanks

The D315 was replaced by the D330 (same 4-1/2” bore and stroke) but different design engine.
The D318 6 cylinder was redesigned into the D318G I think it was called. Believe it was used in the #14 grader and as an industrial engine for a year or maybe two? Then it was replaced by the D333.

The little 4” bore D311 was replaced by a newly designed 4” bore engine and I think the non turbo was still called the D311. The turbocharged version of that small 4 cylinder was the D320.

So to my knowledge, only the D315 was never redesigned, just replaced by the D330.

I may be wrong on this, maybe someone else knows more.

The D315, first gen ended in 1958, then for a short time[5/58 to 59] there was a D315 G series turbocharged and NA version, and just a D315 NA, these were rated at 91hp NA and 115hp turbocharged each at 2000 rpm. These were used for generators and power units.
The early D315's around 1956 came out with crank balancers installed and increased rpm and hp.

Thanks. That jives with what I see. Both the NA and turbo D315 are still in the 1960 Diesel and Gas Engine Catalog rated as Rome K/G states but it sounds like it was gone after that. They're not in the '65 book. Both books had a round-up of the engines available from Cat. D315 is in the '55 and '56 Catalog.

Looking at the '49 (first D4 test with the D315) and '55 Nebraska tests of the D4, I see different power ratings. The '49 shows 54.61 @ 1400 on the belt and 44.01 @ 1400 on the drawbar. The ’55 Nebraska test shows 62.36 @ 1600 belt and 52.19 @ 1600 on the drawbar. The earliest flywheel rating I have is from ’55 and it shows 82 @ 2000 intermittent, 53 @ 1600 continuous (listed for marine engines). The ’60 rating shows the same intermittent rating, 91 @ 2000 max and 62 continuous (for industrial). I see that the ’49 engine is listed with a 17.3:1 compression ratio and the ’55 at 18:1. The dampener probably allowed the higher speed rating. The CR increase probably had a slight effect on the increase.

Yesterday, I saw a genset online that was direct start. No context on it. Was that a factory option or could that have been an aftermarket thing, or something that came later?

I just talked to Kenny III yesterday and he said the engine will be going back in within a month, so their D4 will soon come back to the world of the living.

Hi Team,
to help answer your D315 production span dates, this scan of a Product Bulletin announcement from June 30 1960 should help.
Any D315's sold after this date would be New Old Stock and should mark the end of production, albeit likely to have been before this date due to tooling up for this new engine family.
Hope this helps.
Cheers,
Eddie B.

That helps a lot, many thanks!

Guys, the D315 story is out in Diesel World, the September 2020 issue. Should be on stands now where Diesel World is carried. Thanks for the help, gents!

"edb" wrote:

Hi Team,
to help answer your D315 production span dates, this scan of a Product Bulletin announcement from June 30 1960 should help.
Any D315's sold after this date would be New Old Stock and should mark the end of production, albeit likely to have been before this date due to tooling up for this new engine family.
Hope this helps.
Cheers,
Eddie B.

I have a 1960 D6 955E Traxcavator with a D315 S/N 12A-08263. The latest casting date I have located on the 955E so far is R MD AD (4/29/59). Which leads me to believe they were slowing down on the casting trying to use up their warehoused Stock on Traxcavators and generators. Today I was wondering why the casting dates were just a tad older. That would explain why the casting dates were out of sync and it only makes good fiscal sense.
The 12A sires ended with 12A-08418 most likely mid to late 1960 with the end if the E sires. Then I found the F sires made in Britain. That is all I could find on the F and I had to enhance it to see anything; I'm not sure of the diesel engine size nor sires prefix. However, I was under the impression the pony engine was built until 1964 but like Edie B. said after 6/30/60 they would have been sold as new old stock.

My dad and I did get the engine back in our D4 and it runs and works great. I was very excited that the clutches and brakes worked great as well. We dug it out of a woods up by Rosebush Michigan. The winch on the back works as well with no issues. The only thing left is to put the blade and hyd. Unit back on it. Thanks again Jim for you story you involved my dad and I I’m and to everyone else I would get a copy of the magazine and read it. Very well done!