D342 Head to Block Clearance - Feeler Gauges

[631G]

I cannot find the clearance tolerance for the flatness of the block to check with a straight edge and feeler gauges. Does anyone know what we need to have before reinstalling the heads so we know if we're going to need to deck the block?

I've looked and looked for the engine serial number but cannot locate it. I guess it's been painted over or I am not looking in the right places.

The machine series number is 66A7860

 

[bccat]

What you have is a D9G, with a D353 engine, I would think the specs would be the same as an D342, also liner protrusion,. Is it a spacer plated eng?

 

[chidog]

I don't have the spec handy but I'd guess a hair. About .003, the less the better.

I saw a reference to .002 with in 6 inches or .006 overall but ? Not from cat manual.

 

[OzDozer]

66A7860 is a D9G built in 1969, and the engine in it is a D353, not a D342.

AFAIK, cylinder head warpage specifications are never given for the D353, but a cylinder head thickness is normally given, and this thickness figure usually has a maximum tolerance of .002" to .003".

 

[nicky 68a]

TC Tractors will be the chap that will know

 

[631G]

What you have is a D9G, with a D353 engine, I would think the specs would be the same as an D342, also liner protrusion,. Is it a spacer plated eng?

The engine is not a spacer plate engine based on what our mechanic is telling me and on visual inspection. I think that the machine has had its original engine replaced with a motor out of a genset or other donor at some point.

Ill get some photos up of the engine torn down.

 

[631G]

Here are some general photos and the best photos I could get of what I think could be the engine block serial numbers?

 

[tctractors]

You would only shave the block if it was badly out of shape on a total rebuild including a counter bore cut or insert repair, the blocks are usually showing some distress front to back and side to side with the mid point between 3 and 4 cylinder that is not covered with the head joints as a good indication of the wear state, you might also need to look for the " V " marks on the block surface to gauge if it has had a trim, the liner hight projection should be checked as she stands, also as soon as the heads are lifted I always lightly clamp down the liners with bolts and washers so they cannot move on engine turning, the bold answer to your question is long serving D8 and D9 blocks take hell of a battering and always show lots of wear, I can post the CAT spec' but it would be a marvel to find a 50 year + block still within limits, but the block will still possibly work well, why have you lifted the heads would be more interesting.

 

[631G]

You would only shave the block if it was badly out of shape on a total rebuild including a counter bore cut or insert repair, the blocks are usually showing some distress front to back and side to side with the mid point between 3 and 4 cylinder that is not covered with the head joints as a good indication of the wear state, you might also need to look for the " V " marks on the block surface to gauge if it has had a trim, the liner hight projection should be checked as she stands, also as soon as the heads are lifted I always lightly clamp down the liners with bolts and washers so they cannot move on engine turning, the bold answer to your question is long serving D8 and D9 blocks take hell of a battering and always show lots of wear, I can post the CAT spec' but it would be a marvel to find a 50 year + block still within limits, but the block will still possibly work well, why have you lifted the heads would be more interesting.

TC,

We aren't totally sure what happened to cause pressure to begin leaking into the cooling system. What we witnessed was that we started to see pressure build up in the radiator and the pressure relief valve on the top of the radiator would start opening. Our best guess, we think that the engine was shut down prematurely before allowing enough cooling at low idle to occur and that may have warped the heads. The old heads were not both factory given they had different sized valve guides to give us an indication of that. No idea on age of the heads.

We'll use yours and the other men's input as we begin checking over the block deck and its current tolerance and liner projections. The heads we got are new aftermarket heads so we feel secure in that they'll be in spec for straightness etc.

 

[OzDozer]

None of the photos help identify the engine. I'm struggling to read the part number on the casting, but I think it's 2M5361, which is simply designated a "cover" - a cover plate that fits virtually all D353 engines.

There's a substantial range of different part numbers for D353 engine blocks, indicating a lot of changes along the design pathway.
The engine block casting number on Cat engines is generally in the centre of the block on the LHS, facing forward.
If you can find that casting number, I can check the Numerical Part Record that I have on microfiche, which will advise us what serial number and model it was used in.