eibbed 60 #1 Posted March 5, 2011 :thumbs: I have an opportunity to purchase a K91 T 557290 Spec. NO. 31497A for my 1960 Suburban 400 Is this the correct engine for it? Dave Share this post Link to post Share on other sites
racinfool40 202 #2 Posted March 5, 2011 going by the manual for the 400 suburban it list only one spec# 31388a but has been wrong before..Someone who knows more about these tractors should be along shortly to clear it all up.. the spec #you listed should be close31497a: walbro carb fairbanks morse recoil start coil magneto ignition as far as I can tell from the Kohler manual???? :thumbs: Share this post Link to post Share on other sites
sorekiwi 761 #3 Posted March 5, 2011 My listing agree's with what Mike just said. Share this post Link to post Share on other sites
MikesRJ 551 #4 Posted March 6, 2011 Both my sources say 31388a as well. Share this post Link to post Share on other sites
Kelly 1,028 #5 Posted March 6, 2011 I say buy it and use it till you find the correct one, that may take years to find, enjoy it now, it's only a few bolts and most people will never know. Share this post Link to post Share on other sites
eibbed 60 #6 Posted March 6, 2011 I just got back from looking at the motor. Unfortunately it wasn't in the condition as I was told, so I didn't purchase it. I already have some 4HP Kohlers, but this one was supposed to be like new, supposedly never having had gas run through it. Not so! Most of the four 4HP Kohlers I already own are missing their tins, or don't have the identification tag, so I don't have any numbers to go by. They also have different size diameter crank shafts and different size exhaust port openings. What would be the correct diameter of the crank shaft and exhaust port opening for a 31388a motor? Heck, I may have one and not know it. That would be nice. Thanks to each of you for your help! Dave Share this post Link to post Share on other sites
MikesRJ 551 #7 Posted March 6, 2011 Kohler K90/K91 Crankshaft Dimensions, PTO Extension End 3/4" Diameter straight shaft, 2-3/8" long, 3/16" Key-way, with or without a 3/8-24 UNF-2B tapped hole in the end of the shaft. RE: http://www.mywheelhorse.com/graphics/file/...ence-Manual.pdf Share this post Link to post Share on other sites
VinsRJ 721 #8 Posted March 6, 2011 The exhaust port for a 400 Suburban K91 would be tapped 3/4-14 NPT without mounting studs. The majority of K91s you will find (non- ) will have untapped ports and two exhaust studs. Share this post Link to post Share on other sites
eibbed 60 #9 Posted March 6, 2011 Wow! Thanks Mike and Vince. You guys are good! I just checked my motors and the dimensions lead me to believe that one of them is the correct motor. I appreciate you all very much. Dave Share this post Link to post Share on other sites