Metric Bolts On CTD?

[Northrunner]

What a surprize!, I had to put a new thermostat in my truck recently. It was my 1st repair since I bought the truck used. First socket was to small for the bolts, next size larger was to big. What the heck? These can't be metric, can they? Oh my gosh!, somebody put metric bolts on my truck! I was not expecting that. Is the whole motor metric?, I haven't checked that out yet. Where are these Cummins motors built anyway?

 

[illflem]

Remember when we were supposed to switch over to metric a few years back? Well it seems we only got half way, many vehicles are a mix of English and metric sizes. The Cummins engine is all metric though.

 

[Joe G.]

This mix of metric and inch stuff can drive you crazy. If automobiles are going to switch to metric I wish they would do it and quit messing around. If not, stop using metric stuff all together. Haveing to use two sets of wrenches and sockets on the same vehicle is a PITA to say the least.

 

[JGK]

You'll also note that the metric sizes DC uses are often the odd size compared to most other uses. I guy here in town the owns a tool store and apparently worked at DC (when it was just C) when they were "encouraged" to change to metric said that was C's way of thumbing their nose at the edict. Don't know if that's true. But now we're stuck with it.

 

[Joseph Donnelly]

Yep the engine is all metric, except the pipe plugs. The block plate has metric threads for the starter (M10x1. 5) but American (3/8 x 16) for the bellhousing. The flywheel has American threads for the clutch (5/16 x 18) and the pilot bushing/bearing hole is 1".



some sizes to have handy: lots of bolts have flange heads, 10 mm. A few take 12 (fuel nut), 13 (oil pump, cam retainer, rocker stands), 14 (valve adjustment), 15 (valve covers, crank dampener, etc), 16 (bolt holding oil filler strap to head), 17 (fuel banjo bolt), 18 (head bolts), 19 (fuel banjo; injector lines), 22 (alternator nut), 23 (main cap bolts), 24 (12 valve injector nuts) on and on. American wrenches can be used for 16 (5/8), 19 (3/4), and 24 (15/16).