Mechanical head on hydraulic block, 2.4TD Volvo six

[v8volvo]

Hi all,

Haven't posted here in a couple of years since I sold my Rabbit and got involved with diesel Volvos (2.4L VW I-6, a 1.6 with 2 more holes). Nice to see a lot of the same familiar names still around.

I'm back this time with a question I haven't had any luck finding the answer to so far, and wondering if anyone on here has some good guesses. I am rebuilding a D24T engine (aka 2.4L TD) for a 1985 740 that suffered a couple of different major failures. The original block was beyond repair so I had to start over with a different one, but had quite a bit of trouble finding a replacement. All the diesel Volvos sold in the US (final year was 1986) had solid lifters, but the block I eventually found was actually out of a slightly later-model Pinzgauer military truck, which originally had hydraulic lifters. The part numbers on the "new" block are slightly different -- original mechanical-lifter Volvo was 072 103 011 while the later hydraulic Pinzgauer block is 072 103 021. The funny part is that this Pinzgauer motor had already been rebuilt once before, and actually already had a mechanical head installed on it. I never saw it run that way, but apparently it did (I got it after it had already blown up because of a water pump failure).

My intention is to overhaul the block and install the Volvo's mechanical head on this later, originally hydraulic block. Comparing the hydro block to the mechanical block, I can see no visual differences at all except for the different engine codes (NY for the Pinz vs DM for the Volvo) and part numbers (as above). It looks like on the 1.6 motors with solid vs hydraulic blocks, the hydro motors have an extra oil drain in the casting, but I don't notice any such difference on the 2.4L. Anyone specifically know what the difference may be between these two different blocks? I imagine the different part number must mean there is some mechanical change, but I can't see anything so far. Anyplace else I might want to look?

Looking around on here I see most people talking about putting hydraulic heads on mechanical blocks. Has anyone done the reverse, and if so, anything else I ought to keep in mind?

Thanks in advance.
-v8volvo

[Fatmobile]

I was surprised to see you posting.
Keeping true to your Volvo username eh?
Sorry I can't help with your question about rare beast.

[Quantum-man]

I'd look for pictures of both headgaskets and compare.
Seeing as there are no internal pushrods; all you have to do is seal in the water and oil...

[surfcam]

I would check if you have oil squirters on the inside and same size oil pump on the army one. This will establish weather or not it's a true turbo block.

[v8volvo]

Thanks for the responses. Yep, back to driving Volvos now, but they still have VW diesels under the hood anyway. Best of both worlds.

Headgaskets are listed as the same for the two motors. Both are turbo blocks, both have squirters and the oil pumps are the same part #. Can't find anything to account for the different block numbers, but I suppose that means it should be good to use. As long as all the holes on the block and the head line up, can't go wrong -- I hope...!

Bolting it together this weekend. I'll put up pictures once it's done. Thanks.