Yanmar 3T Series Head (3T82B) Casting Marks Question

[calinb]

I have a 3T84HLE-TBS Yanmar engine in my old Tekeuchi TB25 excavator (probably early 80s vintage). I tore it down, because it has two pistons with broken rings (My cylinder head has as casting mark, "3T82B" under the valve cover the head. I'm thinking about buying a complete overhauled head from a 1985-1986 John Deere/Yanmar Model 276 D that has the same casting mark, which I believe is the head ID mark. However, the two heads have another casting mark that differs. I think it is probably a production run or revision mark. I have a "77H 5 27" casting mark where the head that's for sale has a "7H 925" mark. I've studies several photos of the head that's for sale (online) and can find no other differences between the two heads.

I sure would greatly appreciate any advice.

 

[Birken Vogt]

I don't think you are going to find anyone that has held onto that info for that long, but this would be the place if that info existed.

We don't usually rebuild engines that small, though. It seems the box of parts costs as much as a whole new engine ready to install. And don't have to worry about anyone's assembly skills. And a used engine even better. What are your thoughts on that?

 

[calinb]

I don't think you are going to find anyone that has held onto that info for that long, but this would be the place if that info existed.

We don't usually rebuild engines that small, though. It seems the box of parts costs as much as a whole new engine ready to install. And don't have to worry about anyone's assembly skills. And a used engine even better. What are your thoughts on that?

Thanks for your reply, Birken. I agree. I think a box of Japanese Yanmar OEM parts for a complete engine rebuild (or even just a service limits overhaul) would often cost more than a complete engine, but that replacement engine would be a Chinese copy and not a Yanmar. I've seen Chinese versions of my little Yanmar on aliexpress and alibaba online for only $5000 plus shipping.

I only need a top end overhaul so I think it's worth installing Yanmar OEM parts but I'm trying to decide if I should get the overhauled head off ebay or get my head magnifluxed and have a shop put in my new parts.

 

[Birken Vogt]

I was saying box of parts cost as much as a new engine from the dealer but that was referring to my experience with engines from this century. I don't know how it would work out with old stuff like that.

 

[calinb]

I was saying box of parts cost as much as a new engine from the dealer but that was referring to my experience with engines from this century. I don't know how it would work out with old stuff like that.

That's easy to believe. I read years ago that someone priced out every part in an automobile (don't recall which auto or brand) and it cost 5 times more to buy the parts and build the car than to buy it complete. Equipment is different than the automobile market in many ways but might be similar in this respect.

I'm not sure that dealers can even get this 40-year old engine new from Yanmar. I think the options for a new engine are all Yanmar clones from China (and they aren't exact clones either) but at least I found all the parts I needed and they were all stateside. I had to buy from a Takeuchi dealer and also a Yanmar dealer to get everything I needed. One said the pistons were discontinued and the other said the gasket set was discontinued but, between the two of them, I found everything.

 

[Birken Vogt]

I haven't got yours in front of me, but I do know they still make a 3TNE and/or 3TNV, and knowing these mfrs, would not be surprised if they were quite similar. Isuzu also rebadges it as a 3Cxx.

 

[calinb]

I haven't got yours in front of me, but I do know they still make a 3TNE and/or 3TNV, and knowing these mfrs, would not be surprised if they were quite similar. Isuzu also rebadges it as a 3Cxx.

I bet that engine could be fit to my TB25 without too much difficulty. I wonder how much Takeuchi or Yanmar wants for a new one.

 

[Birken Vogt]

A couple of years ago 5-6 grand would have been my guess, nowadays who knows or how long it might take to get one.