Posted September 09, 2011 - 11:11 PM
Posted September 10, 2011 - 11:01 AM
Posted September 11, 2011 - 09:27 AM
If you take a look at the following manual for the Suburban 400 it details the pipes required. The pipe used is standard 3/4" Black Pipe available at any home store or plumbing supply place.
The dimensions of the pieces are (pipe length dimensions are measured from center of threads to center of threads, not the entire length of the pipe):
Item 15 (WH p/n: 3487, "Nipple Pipe"): 3/4" x 1" long nipple
Item 16 (WH p/n: 3488, "Nipple Pipe"): 3/4" x 14-1/2" long Black Pipe
Item 17 (WH p/n: 3489, "Elbow"): 3/4" to 3/4" 90 degree Black Pipe Elbow
Item 18 (WH p/n: 3490, "Elbow"): 3/4" to 3/4" 45 degree Black Pipe Elbow
Item 23 (WH p/n: 1192, "Nipple, Close"): 3/4" x 1" long nipple ***
*** Though Wheel Horse called for a "close nipple" (normally interpreted as a 1" threaded black pipe nipple) for the nipple which the muffler threads into, I personally used a 2" to 3" pipe to keep the muffler away from the freshly painted hood. You choice of course, but I have done this to preserve the paint over the long haul. I also angled the last elbow down a little for the same reason. Shown below is a 2" nipple angled down about 20 degrees. Another word of advice is to paint the pipe with flat black high-temp grill paint to keep the pipe from rusting. I also did this after I noticed the pipe was rusting from the inevitable heating and cooling, and moisture condensation.
Edited by MikesRJ, September 11, 2011 - 11:33 AM.
- caseguy, Texas Deere and Horse, Ranchkingron and 1 other said thanks
Posted September 11, 2011 - 10:48 AM
Posted September 11, 2011 - 11:32 AM
On a good note though, the hole that exists under that flange is almost exactly the correct size (within a few thousandths) of a 1/2" NPT (National Pipe Thread) pipe tap. You can get a 1/2" NTP pipe tap at any good home center or hardware store, stuff a small wad of paper towel in the exhaust port hole(to keep chips out of the exhaust port valve stem area), cut the threaded studs flush with the flange, tap the hole using plenty of oil, thread a 1/2" Close pipe nipple into the hole, and use a 1/2" to 3/4" 90 degree elbow. The reduced port size for that short distance will not effect the engine at all.
WARNING: Be careful going to a 3/4" tapped hole on a studded engine. Most of them do not have the "meat" around the exhaust port channel to support a 3/4" pipe without making the wall thickness excessively thin. The block castings for the correct-spec engines had a bit more metal in that area. I suggest using my previous method, or find a correct-spec or threaded port engine. Another option, which is certainly a decent one, is to have a machine shop make you a flange with a threaded nipple pipe welded into it. Then you just bolt the new flange into place and start off the rest of the exhaust system with the 3/4" 90 degree elbow. You may need to replace the studs with shorter ones, but that's pretty cheap to do.
Edited by MikesRJ, September 11, 2011 - 11:42 AM.
- Texas Deere and Horse and Clippnalawn have said thanks
Posted September 11, 2011 - 05:22 PM
Posted September 11, 2011 - 10:04 PM
Edited by MikesRJ, September 11, 2011 - 10:09 PM.
Posted September 12, 2011 - 10:19 PM