Cat 3304 piston height

Don't you still have an old piston to compare? Set the two upside down on a flat surface and slide a pin through them to check.

Hi CF,
Only Cat(Perkins) engines I ever saw piston deck height specs for were the Perkins engines Cat Used.
When we fitted new pistons to these it eventually turned out the selective fit pistons, to get equal D H's, were for Assembly Line usage ONLY on NEW engines.
We had only one Part No piston available in the Cat parts system for Dealer use.
We always found they met specs anyway.

As for real Cat engines I do not ever recall seeing a spec for piston deck height or did I ever check any of them.

Can only suggest you check/compare the old and new pistons as CCJ said.

Different story with the old early 1930's designed English 5LW Gardner engines I worked on--very rigid specs for those old beasts that even today have better BSFC figures than most modern diesels. A true mechanics engine that I enjoyed working on albeit time consuming, but, the results were very satisfying as they ran so well.
Cheers,
Eddie B.

I measured the ring wear on the old liners and the pistons. They appear to have the same dimensions. I could be off as much as .020" using eyeball, and mic. It may just be the valve reliefs cut into the piston to the edge of the piston caught my attention. After all, I did check the actual part# on old and new pistons and they do cross. Also, this is the only 3300 series piston with a 1.5" wrist pin and it is for the pre combustion style engine. The pistons should be fine.

I am worried about the replacement crank I installed. The box showed it as having a small gear installed. However, I did have to swap out the gears because the new gear was a lot wider, it would have interference problems with the cover. Does any body know if there were several cranks offered for 3304 series? Or did I get the right crank with a 3306 timing gear installed by mistake? For example, I see a note on the clevite parts list for 3304 short nose crank. However They only show one part # for 3304 crank. I have a call in to the parts person I am dealing with, but it will be Monday before I can get his help. It also appears the new crank has a little longer nose. . . See my concern.

I am dealing with a Mitsubishi made cat, but I have not had too many parts problems.

The CAT engine piston to cylinder hight is somewhat hard to view by eye to establish the correct piston hight due to the raised top edge of the cylinder liner in relation to the clamping outer edge of the liner, if I cannot see the V mark stamped into the cylinder block deck on CAT engines I check piston hight, any compression ratio changes on CAT or Cummins engines near always only involve the ring hight on the pistons, the Perkins engines owned by CAT for 20 plus years use dry liners in the small engine series in I think 3 grades un-finished, semi-finished and pre-finished, the last 1 needing no boring or hone work, the pistons are also supplied in Standard or Pre-Topped as the piston hight needs checking on these engines always even if pre-topped pistons are used, there is tooling to machine by hand the piston hight to the correct standard (piston in bore), or the piston/s need stripping from the bore and machining down to spec, the 3304/6 pistons change shape and form with the cast in ring lands and oil control ring width followed by the oil spray style cut outs on the lower skirt edge, the bore and stroke of the piston is constant through the engine range, I have never measured the hight of the top step on the cylinder liners to the protrusion ledge but 40 thou or more sounds handy, but the safety tip on CAT motors is to look for the V stamped into the block face that mates with the V on the piston crown, if the V is missing on the block its been "Decked" needing the piston hight checking.
tctractors